CALCULATION OF REGISTRATION FEE

Title of each class of securities to be registered		Amount to be Registered				Proposed maximum offering price per unit				Proposed maximum aggregate offering price				Amount of registration fee
LLC interests			6,109,375	(1)		$	80.00	(1)		$	488,750,000	(1)		$	56,792.75	(2)

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Filed pursuant to Rule 424(b)(2)
Registration No. 333-187794

PROSPECTUS SUPPLEMENT
(To Prospectus dated April 8, 2013)

5,312,500 Shares

Macquarie Infrastructure Company LLC

We are selling 5,312,500 of our limited liability company interests, or shares. Our shares trade on The New York Stock Exchange, or the NYSE, under the symbol “MIC.” The last reported trading price of our shares on February 25, 2015 was $81.25.

Investing in our shares involves risks. See “Risk Factors” beginning on page S-16 of this prospectus supplement and in our Annual Report on Form 10-K for the year ended December 31, 2014, which is incorporated by reference into this prospectus supplement and the accompanying prospectus.

		Per Share				Total
Price to the public		$	80.00			$	425,000,000
Underwriting discounts and commissions		$	2.60			$	13,812,500
Proceeds (before expenses)		$	77.40			$	411,187,500

We have granted the underwriters the option to purchase up to 796,875 additional shares within 30 days of the date of this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The underwriters expect that delivery of the shares will be made to investors against payment therefor on March 2, 2015 (this settlement cycle being referred to as “T+2”).

Joint Book-Running Managers

Barclays

Macquarie Capital

J.P. Morgan

RBC Capital Markets

SunTrust Robinson Humphrey  

Lead Co-Managers

Oppenheimer & Co.				Wells Fargo Securities

Co-Managers

BofA Merrill Lynch		BBVA		BB&T Capital Markets
Credit Agricole CIB		JonesTrading Capital Markets		Regions Securities LLC

Prospectus Supplement dated February 25, 2015.

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PROSPECTUS SUPPLEMENT

About this Prospectus Supplement			S-iii
Industry and Market Data			S-iii
Forward-Looking Statements			S-iii
Prospectus Supplement Summary			S-1
The Offering			S-12
Summary Financial Data			S-13
Risk Factors			S-16
Use of Proceeds			S-23
Capitalization			S-24
Material U.S. Federal Income Tax Considerations			S-25
Underwriting			S-30
Legal Matters			S-36
Experts			S-36
Where You Can Find More Information			S-36
Incorporation of Certain Documents by Reference			S-37

PROSPECTUS

About this Prospectus			ii
Prospectus Supplement			ii
Forward-Looking Statements			ii
Where You Can Find More Information			iv
Incorporation of Certain Documents by Reference			iv
Macquarie Infrastructure Company LLC			1
Risk Factors			3
Use of Proceeds			8
Ratio of Earnings to Fixed Charges			9
Description of our Shares			10
Description of Debt Securities			16
Material U.S. Federal Income Tax Considerations			25
Selling Security Holder			30
Plan of Distribution			31
Legal Matters			33
Experts			33

Macquarie Infrastructure Company LLC is not an authorized deposit-taking institution for the purposes of the Banking Act 1959 (Commonwealth of Australia) and its obligations do not represent deposits or other liabilities of Macquarie Bank Limited ABN 46 008 583 542 (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of Macquarie Infrastructure Company LLC.

We have not, and the underwriters have not, authorized any dealer, salesperson or other person to give any information or to make any representation other than those contained in or incorporated by reference into this prospectus supplement, the accompanying prospectus or any free writing prospectus that may be provided to you by us or on our behalf. You must not rely upon any information or representation not contained in or incorporated by reference into this prospectus supplement, the accompanying prospectus or any free writing prospectus that may be provided to you. This prospectus supplement, the accompanying prospectus and any such free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate. Nor do this prospectus supplement, the accompanying prospectus or any such free

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writing prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction. You should not assume that the information contained in this prospectus supplement, the accompanying prospectus, the documents incorporated herein and therein by reference and any such free writing prospectus is correct on any date after their respective dates, even though this prospectus supplement, the accompanying prospectus and any such free writing prospectus are delivered or securities are sold on a later date. Our business, financial condition, results of operations and cash flows may have changed since those dates.

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the terms of the offering of our shares and also adds to and updates information contained in the accompanying prospectus as well as the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part is the accompanying prospectus, dated April 8, 2013, which we refer to as the “accompanying prospectus,” which gives more general information about our shares that we may offer from time to time. Generally, when we refer to “this prospectus” in this prospectus supplement we are referring to both this prospectus supplement and the accompanying prospectus combined. This prospectus incorporates by reference important business and financial information about us that is not included in or delivered with this prospectus. You should read both this prospectus supplement and the accompanying prospectus together with the additional information below under the headings “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference.”

You should rely only on the information contained in or incorporated by reference into this prospectus supplement, the accompanying prospectus or any free writing prospectus provided by us or on our behalf. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or any document that has previously been filed with the Securities and Exchange Commission, or the SEC, and is incorporated into this prospectus by reference, on the other hand, the information in this prospectus supplement shall control. We have not, and the underwriters have not, authorized any other person to provide you with different information or representations.

INDUSTRY AND MARKET DATA

In this prospectus supplement and the accompanying prospectus (and the documents incorporated by reference herein or therein), we rely on and refer to information and statistics regarding market data and the industries of our businesses and investments obtained from market research, independent industry publications and other publicly available information. We believe this information is reliable but we have not independently verified it. In addition, we have made statements in this prospectus supplement and the accompanying prospectus regarding our industry and our position in the industry based on our experience in the industry and our own evaluation of market conditions.

FORWARD-LOOKING STATEMENTS

We have included in or incorporated by reference into this prospectus supplement certain statements that may constitute forward-looking statements. These include without limitation those under the headings “Prospectus Supplement Summary — Macquarie Infrastructure Company LLC,” “Prospectus Supplement Summary — Recent Developments — BEC Acquisition” and “Risk Factors,” as well as those contained in any applicable prospectus supplement and the accompanying prospectus or in any document incorporated by reference into this prospectus supplement and the accompanying prospectus. In addition, our management may make forward-looking statements to analysts, investors, representatives of the media and others. These forward-looking statements are not historical facts and represent only our beliefs regarding future events, many of which, by their nature, are inherently uncertain and beyond our control. We may, in some cases, use words such as “project,” “believe,” “anticipate,” “plan,” “expect,” “estimate,” “intend,” “should,” “would,” “could,” “potentially,” “may” or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements.

In connection with the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, we are identifying important factors that, individually or in the aggregate, could cause actual results to differ materially from those contained in any forward-looking statements made by us. Any such forward-looking statements are qualified by reference to the following cautionary statements.

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Forward-looking statements in this prospectus supplement (including any documents incorporated by reference herein) are subject to a number of risks and uncertainties, some of which are beyond our control, including, among other things:

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Our actual results, performance, prospects or opportunities could differ materially from those expressed in or implied by the forward-looking statements. A description of risks that could cause our actual results to differ appears under the caption “Risk Factors” and elsewhere in this prospectus supplement and in the documents incorporated by reference into this prospectus supplement. It is not possible to predict or identify all risk factors and you should not consider that description to be a complete discussion of all potential risks or uncertainties that could cause our actual results to differ.

In light of these risks, uncertainties and assumptions, you should not place undue reliance on any forward-looking statements. The forward-looking events discussed in this prospectus supplement (including any documents incorporated by reference herein) may not occur. These forward-looking statements are made as of the date of this prospectus supplement, such as our Annual Report on Form 10-K for the year ended December 31, 2014. We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law. You should, however, consult further disclosures we may make in future filings with the SEC. See “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference” in this prospectus supplement.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights information incorporated by reference into or contained elsewhere in this prospectus supplement and the accompanying prospectus. This summary may not contain all of the information that may be important to you. You should read carefully all of the information contained in or incorporated by reference into this prospectus supplement and the accompanying prospectus, including the information set forth under the caption “Risk Factors” beginning on page S-16 of this prospectus supplement and page 3 of the accompanying prospectus, and in our Annual Report on Form 10-K for the year ended December 31, 2014 and our consolidated financial statements and the related notes thereto incorporated by reference herein before making a decision to invest in our shares.

Macquarie Infrastructure Company LLC, a Delaware limited liability company, was formed on April 13, 2004. Except as otherwise specified, “Macquarie Infrastructure Company,” “MIC,” “MIC LLC,” “the Company,” “we,” “us,” and “our” refer to Macquarie Infrastructure Company LLC and its subsidiaries together from June 25, 2007 and, prior to that date, to Macquarie Infrastructure Company Trust, the Company and its subsidiaries. Macquarie Infrastructure Management (USA) Inc., which we refer to as our Manager, is part of the Macquarie Group, comprising Macquarie Group Limited and its subsidiaries and affiliates worldwide.

Macquarie Infrastructure Company LLC

We own, operate and invest in a diversified group of infrastructure businesses that provide basic services to businesses and individuals primarily in the U.S. The businesses we own and operate include:

Our businesses generally operate in sectors of infrastructure with barriers to entry, including high initial development and construction costs, the existence of long-term contracts or the requirement to obtain government approvals and a lack of immediate cost-efficient alternatives to the services provided. Overall they tend to generate sustainable, stable and growing cash flows over the long term.

We have elected to treat MIC as a corporation for federal tax purposes. As a result, all investor tax reporting regarding dividends and/or return of capital will be provided on Form 1099.

Dividends

We view MIC as a total return investment opportunity. In particular, we believe that the growth in Free Cash Flow generated by our businesses could result in dividends per share growing at 14% for at least the next two years. Consistent with that view, we currently intend to maintain a payout ratio between 80% and 85% of the Free Cash Flow generated by our business in the form of a quarterly cash dividend to our shareholders, subject to maintaining a prudent level of reserves and without creating undue volatility in the amount of such dividends where possible. We define Free Cash Flow as cash from operating activities, which reflects cash paid for interest, taxes and pension contributions, less maintenance capital expenditures, which includes principal repayments on capital lease obligations used to fund maintenance capital expenditures, and

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excludes changes in working capital. From 2007 through 2014, our underlying proportionately combined Free Cash Flow per share grew at a compound annual rate of 13.1% per year.

On February 17, 2015, the Board of Directors declared a dividend of $1.02 per share ($4.08 annualized) for the quarter ended December 31, 2014. The dividend is expected to be paid on March 5, 2015 to shareholders of record at the close of business on March 2, 2015. This offering is expected to close on or prior to such record date, and therefore purchasers of shares in this offering that take delivery of such shares on the closing date and continue to hold the shares as of the close of business on March 2, 2015 will receive this dividend on March 5, 2015.

The declaration and payment of any future dividends will be subject to a decision of our Board of Directors. Our Board of Directors will take into account such matters as the state of the capital markets and general business conditions, our financial condition, results of operations, capital requirements, capital opportunities and any contractual, legal and regulatory restrictions on the payment of dividends by us to our shareholders or by our subsidiaries to us, and any other factors that it deems relevant, subject to maintaining a prudent level of reserves and without creating undue volatility in the amount of such dividends where possible. In particular, each of our businesses and investments has debt commitments and restrictive covenants, which must be satisfied before any of them can make distributions to our Company. In addition, our senior secured credit facility contains restrictions on our ability to pay dividends. Although historically we have declared cash dividends on our shares, any or all of these factors could result in the modification of our dividend policy, or the reduction, modification or elimination of our dividend in the future.

Our Manager

We are managed externally by Macquarie Infrastructure Management (USA) Inc., our Manager. Our Manager is a member of the Macquarie Group, a diversified international provider of financial, advisory and investment services. The Macquarie Group is headquartered in Sydney, Australia and is a global leader in management of infrastructure investment vehicles on behalf of third-party investors and advising on the acquisition, disposition and financing of infrastructure assets.

We have entered into a management services agreement with our Manager. Our Manager is responsible for our day-to-day operations and oversees the management teams of our operating businesses. At the holding company level, we do not have any employees. Our Manager has assigned, or seconded to us, two of its employees to serve as our chief executive officer and chief financial officer and seconds or makes other personnel available as required. In addition, our Manager has appointed the chairman of our Board of Directors and an alternate, subject to minimum equity ownership. The services performed for us by our Manager are provided at our Manager’s expense, and include the compensation of our seconded personnel.

We pay our Manager a monthly base management fee based primarily on our market capitalization. Our Manager can also earn a performance fee if the quarterly total return to shareholders (capital appreciation plus dividends) exceeds the quarterly total return of a U.S. utilities index. For our Manager to earn the performance fee, our quarterly total returns must be positive and in excess of any prior underperformance. If payable, the performance fee is equal to 20% of the difference between the benchmark return and the return for our shareholders. Our Manager may, in its sole discretion, choose to receive its base management and/or performance fees, if applicable, in cash or to reinvest such fees in additional shares. Our Manager’s election to invest its fees in shares can only change during an 18 trading day window following our earnings release. Any change would apply to fees paid thereafter. Accordingly, shareholders would have notice of our Manager’s intent to receive fees in cash rather than reinvest before the change is effective. The price for such shares is calculated based on the volume weighted average trading price of our shares over a specified period of time up to a maximum share price that is equal to double the closing share price of our shares on the last day of the election window.

During 2014, our Manager became entitled to base management fees of $46.6 million and performance fees of $121.5 million. Consistent with the management services agreement, our Manager elected to reinvest all of the base management fees and performance fees to which it became entitled in additional shares of our Company. However, for the third quarter of 2014, the Board of Directors requested, and our Manager agreed, that $65.0 million of the performance fee be settled in cash using the proceeds from the sale of the district energy business in order to minimize dilution.

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Industry Overview

Infrastructure businesses, in general, are defined by a combination of the following characteristics:

Different infrastructure businesses exhibit these characteristics to different degrees at different times. For instance, businesses that correlate to gross domestic product, like Atlantic Aviation, may exhibit more volatility during periods of economic downturn than businesses with more contracted revenue streams. While not every business that we own will meet all of the general criteria described above, we seek to own a diversified portfolio of businesses that possesses a balance of the characteristics described above.

In addition to the benefits associated with these characteristics, the revenues generated by most of our infrastructure businesses generally can be expected to keep pace with historically normal rates of inflation. The price escalators built into many customer contracts, and the inflation and cost pass-through adjustments typically a part of pricing terms or provided for by the regulatory process to regulated businesses, serve to insulate infrastructure businesses to a significant degree from the negative effects of inflation and commodity price risk. We sometimes employ hedging contracts in connection with our businesses’ floating rate debt and limited commodity price exposure.

Our existing businesses can be categorized as follows:

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Our Business Strategy

Our corporate strategy is to own a diversified portfolio of infrastructure businesses and grow shareholder dividends. We intend to achieve this by:

Our Businesses

Our businesses, along with the industries in which they operate and their strategies, are discussed below.

IMTT

IMTT Business Overview

We owned 50% of IMTT through July 15, 2014. On July 16, 2014, we completed the acquisition of the remaining 50% interest that we did not previously own. IMTT stores or handles petroleum products, various chemicals, renewable fuels and vegetable and animal oils. IMTT is one of the larger independent providers of bulk liquid terminal services in the U.S., based on capacity. IMTT also owns OMI Environmental Solutions (formerly Oil Mop), an environmental emergency response, industrial services, waste transportation and disposal business.

Industry Overview

Bulk liquid terminals provide an important link in the supply chain for a broad range of liquids, such as crude oil (not a material product for IMTT), refined petroleum products and commodity and specialty chemicals. In addition to renting storage tanks, dock access and intra-modal transportation access, bulk liquid terminals generate revenues by offering ancillary services including product transfer (throughput), heating and blending. Pricing for storage and other services typically reflects local supply and demand as well as the specific attributes of each terminal, including access to deepwater berths and connections to land-based infrastructure such as roads, pipelines and rail.

Both domestic and international factors influence demand for bulk liquid terminals in the United States. Demand for storage rises and falls according to local and regional consumption. In addition to these domestic forces, import and export activity also accounts for a material portion of the business. Shippers require storage for the staging, aggregation and/or distribution of products before and after shipment. The extent of import/export activity depends on macroeconomic trends such as currency fluctuations as well as industry-specific conditions, such as supply and demand balances in different geographic regions. Current demand for storage is also driven by fluctuations in the current and perceived future price and demand for the product being stored and the resulting temporal price arbitrage.

Sudden, sizeable and largely unforeseen fluctuations in commodity prices, similar to those experienced in the second half of 2014, can cause the bulk liquid terminals industry to enter a temporary state of flux while participants absorb and analyze the impact of the changes. The 2014 price fluctuations and the reoccurrence of a contango for some commodities gave rise to an increase in demand for storage of those commodities. Conversely, the suddenness of the change in the market caused some participants to avoid making long-term storage commitments. Over time we expect these conditions to stabilize.

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Potential entrants into the bulk liquid terminals business face several barriers. Strict environmental regulations, limited availability of waterfront land with the necessary access to land-based infrastructure, local community resistance to new fuel/chemical sites and high initial investment costs limit the construction of new bulk liquid terminal facilities. These deterrents are most formidable around waterways near major urban centers. As a consequence, new tanks are generally built where existing docks, pipelines and other infrastructure can support them, resulting in higher returns on invested capital. However, restrictions on land use, difficulties in securing environmental permits and the potential for operational bottlenecks due to infrastructure constraints may limit the ability of existing terminals to expand the storage capacity of their facilities.

IMTT Strategy

The key components of IMTT’s strategy are:

We believe that IMTT possesses a number of competitive strengths that increase the likelihood that this strategy would be successful, including:

Prior to the IMTT Acquisition, we accounted for the investment in IMTT under the equity method of accounting. As of the closing date, we consolidated IMTT in our financial statements. The IMTT Acquisition resulted in all assets and liabilities of IMTT being recorded at fair value, including our previous 50% interest in IMTT. This resulted in a pre-tax gain for the year ended December 31, 2014 of $948.1 million in our consolidated condensed statements of operations.

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Atlantic Aviation

Atlantic Aviation Business Overview

Atlantic Aviation operates FBOs at 69 airports in the United States. Atlantic Aviation’s FBOs provide fueling and fuel-related services, aircraft parking and hangar services to owners/operators of jet aircraft, primarily to the general aviation sector of the air transportation industry, but also to commercial, military, freight and government aviation customers.

Industry Overview

FBOs primarily service the general aviation segment of the air transportation industry. General aviation includes corporate and leisure flying and does not include commercial air carriers or military operations. Local airport authorities, the owners of the airport properties, grant FBO operators the right to provide fueling and other services pursuant to long-term ground leases. Fueling services provide the majority of an FBO’s revenue and gross profit.

FBOs generally operate in environments with high barriers to entry. Airports often have limited physical space for additional FBOs. Airport authorities generally do not have an incentive to add additional FBOs unless there is a significant demand for additional services. Government approvals and design and construction of a new FBO can also take significant time and require significant capital expenditures. Furthermore, airports typically impose minimum standards with respect to the experience, capital investment and breadth of services provided by the FBO.

Demand for FBO services is driven by the level of general aviation flight activity. Atlantic Aviation measures general aviation activity level by the number of take-offs and landings in a given period. General aviation business jet take-offs and landings increased by 3.6% in 2014 compared with 2013 according to flight data reported by the Federal Aviation Administration, or FAA. General aviation business jet take-off and landings at locations operated by Atlantic Aviation, which represent approximately 24% of total business jet take-offs and landings, increased by 3.9% for the same period. The business also believes general aviation flight activity will continue to expand along with increased economic activity in the U.S.

Atlantic Aviation Strategy

Atlantic Aviation is pursuing a strategy that has five principal components. These are:

We believe that Atlantic Aviation is well positioned to successfully execute the strategy outlined above based in part on the skill and experience of its management team and its good reputation in the general aviation services industry.

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CP&E

CP&E Segment Overview

The businesses in our CP&E segment sell energy generated by their facilities to creditworthy off-takers, typically pursuant to multi-year contracts. These contracts include either long-term power purchase agreements, or PPAs, or tolling arrangements whereby a counterparty has contracted with the facility to deliver a specified suite of energy and related services. Throughout its existence, we have invested in a range of CP&E facilities including in a district energy business that was one of our seed assets at our initial public offering in 2004. Subsequently, we have invested in electricity generating facilities utilizing wind turbine and solar photovoltaic technologies. We expect to continue to seek attractive opportunities in energy and electricity generation, including renewable and conventional technologies. We will seek to invest in operating facilities and those that are near construction completion.

At December 31, 2014, CP&E consisted of controlling interests in five solar power generating facilities and two wind power generating facilities. The solar power facilities have an aggregate generating capacity of 57 megawatts with two facilities located in Arizona, two facilities located in California and one facility located in Texas. The wind power facilities have an aggregate generating capacity of 203 megawatts and are located in New Mexico and Idaho.

The seven solar and wind projects sell electricity under PPAs with initial terms of 20 – 25 years. The PPAs have fixed rates for each unit of electricity sold and certain of the PPAs have fixed or CPI-linked escalators. Six of the facilities are owned through tax-equity partnership structures in which we have controlling interests. From these we receive cash distributions disproportionate to our investment during the first several years of the projects’ operations and taxable income or taxable loss disproportionate to our interest thereafter. Our interest in the seventh project is an approximately 75% ordinary economic interest.

The renewable energy facilities utilize arrays of photovoltaic solar panels and wind turbine generators (often on sites spanning thousands of acres) to convert energy from sunlight and wind into electricity. The electricity is aggregated and fed directly into the respective regional power grid. These technologies generally produce predictable amounts of electricity, subject to seasonal and annual variability in insolation and wind. The business also generates Renewable Energy Certificates, or RECs, based on the amount of electricity provided to off-takers. These RECs are either bundled with the electricity under the terms of the PPAs or sold separately to third-parties.

In 2014, we acquired controlling interests in two wind power generation facilities and divested our controlling interest in the district energy business, consistent with our strategy of optimizing our CP&E portfolio. In January of 2015, we announced that we had entered into an agreement to acquire a 512 megawatt gasfired simple cycle power generation facility in Bayonne, New Jersey known as the Bayonne Energy Center, or BEC, and the transaction is expected to close in the first half of 2015, subject to receipt of required regulatory approvals and satisfaction of other closing conditions customary in a transaction of this size and type. See “— Recent Developments — BEC Acquisition.”

CP&E is likely to include a range of conventional and renewable energy generation and distribution technologies and may have fully or partially contracted off-take agreements. Contracts are generally with a specific off-taker, a power remarketer or a financial counterparty that provides a hedge against volatility in revenue. Excess generating capacity can be sold in the spot market. Operations and maintenance as well as management and administrative services are often provided by contracted third-parties.

Industry Overview

Without the power industry, no other industrial sectors could exist, making the industry one of the largest in the world in terms of the number and value of projects and facilities. In developed economies, aging infrastructure, new technologies, increased legislation regarding emissions and the use of renewable energy are driving capital spending.

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The Energy Information Administration is forecasting a decline in the growth rate of demand for electricity in the U.S. At the same time, agencies including the Environmental Protection Agency are developing increasingly stringent emission and other standards for the power generating community. As aging and inefficient generating capacity is retired or replaced, opportunities for development of our CP&E segment are expected to increase.

Increased transaction activity in the electricity generating sector of the industry has been driven by a combination of existing generators optimizing their portfolios together with significant renewable power projects being developed as a result of the adoption of Renewable Portfolio Standards, or RPS, in a number of states. RPS are regulatory mandates that aim to create demand for electricity derived from renewable sources by obligating utilities and other load-serving entities to provide at least a specific portion of their electricity sales from qualifying renewable technologies by a specified date.

Demand for both existing and greenfield assets has grown as CP&E projects offer an attractive risk-adjusted return, particularly in a low interest rate environment, which has resulted in increased competition. For example, developers have in some cases formed publicly-listed, yield-oriented entities, or YieldCos, which have access to low-cost capital to construct projects from their own development pipeline and development pipelines for which they have rights of first offer, and to purchase projects from third-parties. Similar to us, the YieldCos tend to have a high distribution payout ratio to provide ongoing distributions to their shareholders.

CP&E Strategy

Businesses within the CP&E segment generate a cash flow stream through a combination of long-term contracted revenues and quantifiable capital requirements. Through our CP&E segment, we hold a portfolio of high-quality assets with predictable cash flow. We are actively looking for opportunities to acquire projects or businesses with similar characteristics, which when aggregated, we believe may generate scale efficiencies.

The strategy behind our CP&E businesses includes the following components:

We believe that CP&E’s successful execution of this strategy will contribute to the continued generation of revenue and cash flows as a result of the long-term contractual relationships with its customers and the management team’s ability to improve the operating performance of the business.

Hawaii Gas

Hawaii Gas Business Overview

Hawaii Gas, founded in 1904, is Hawaii’s only government-franchised gas utility, processing and distributing gas throughout the state. The market includes Hawaii’s approximately 1.4 million residents and approximately 8.3 million visitors in 2014. Hawaii Gas services customers throughout Oahu, Hawaii, Maui, Kauai, Molokai and Lanai, the main islands.

Hawaii Gas’s primary products consist of:

Synthetic Natural Gas, or SNG:  The business converts a light hydrocarbon feedstock (currently naphtha) into SNG. The product is chemically similar in most respects to natural gas and has a similar heating value on a per cubic foot basis. Hawaii Gas has the only SNG processing capability in Hawaii at its plant located on the island of Oahu. SNG is delivered by underground piping systems to utility customers on Oahu. The business generates hydrogen gas as part of the reforming process that creates SNG, the majority of which currently is extracted and sold to one of the local refineries.

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Liquefied Petroleum Gas, or LPG:  LPG is a generic name for a mixture of hydrocarbon gases, typically propane and butane. LPG liquefies at a relatively low pressure under normal temperature conditions. As a result, LPG can be stored or transported more easily than natural gas or SNG. Once on shore, LPG is typically transported in cylinders or tanks. Domestic and commercial applications of LPG are similar to those of natural gas and SNG.

Liquefied Natural Gas, or LNG:  In March of 2014, the business received regulatory approval to utilize LNG as a backup fuel for the SNG utility distribution system and currently utilizes conventional intermodal cryogenic containers to transport LNG from the U.S. mainland. The first shipment of LNG was regasified in April of 2014 and LNG operations have been ongoing since that time.

Renewable Natural Gas, or RNG:  The business continues its initiatives to develop RNG and is now evaluating a range of feedstock sources including municipal waste water treatment plants, landfills and biomass.

The utility business includes the processing, distribution and sale of SNG and LNG on the island of Oahu and the distribution and sale of LPG on all of the main islands. The non-utility business sells and distributes LPG to customers on all the main islands. LPG is delivered by truck to individual tanks located on customer sites or is distributed in cylinders filled at central locations.

The gas distributed by Hawaii Gas has a wide range of commercial and residential applications including water heating, drying, cooking, emergency power generation and decorative lighting, such as tiki torches. LPG is also used as a fuel for specialty vehicles such as forklifts. Users include residential customers and a wide variety of commercial, hospitality, military, public sector and wholesale customers.

Hawaii Gas’s products, SNG, LNG and LPG, are relatively clean-burning fuels that produce lower levels of carbon emissions than other hydrocarbon fuels such as coal or oil. This is particularly important in Hawaii where heightened public awareness of the environmental impact of using hydrocarbon fuels makes lower emission fuels attractive to customers.

Hawaii Gas continues to move forward with initiatives to utilize cleaner-burning fuels, including RNG and LNG. RNG projects under development include the recovery of gas from municipal waste water treatment plants and landfills as well as the processing of locally grown biomass. The source gas for these projects is often controlled, directly or indirectly, by state or municipal government, thereby requiring extended procurement processes.

Hawaii Gas is the only company with regulatory approval to land and utilize LNG in Hawaii, currently as a back-up fuel for its SNG system on Oahu. In October of 2014, Hawaii Gas filed an application with the Hawaii Public Utilities Commission, or HPUC, seeking approval to invest $12.8 million in its utility business for a smaller-scale containerized LNG import project to provide natural gas as a replacement for up to 30% of SNG gas demand. Regular deliveries of containerized LNG would commence approximately six-months after receiving HPUC approval.

Hawaii Gas also continues to work with stakeholders throughout the state to pursue a larger-scale bulk import, storage and distribution program to supply multiple end markets including power generation and ground and marine transportation. In November of 2014, Hawaii Gas launched its Invitation to Bid, or ITB, to more than 55 companies with relevant experience in larger-scale bulk LNG with preliminary bids due in February of 2015. Following a review of the responses, binding bids are expected in the second quarter of 2015, at which time Hawaii Gas will share the findings with the State of Hawaii and key off-takers and identify preferred bidders.

The ITB is consistent with a Memorandum of Understanding, or MOU, signed in December of 2013 by Hawaii Gas and the state’s largest electric utility, the Hawaiian Electric companies, with input from the state. The MOU established key priorities for a larger-scale bulk LNG program as well as a framework for utility collaboration and regulatory oversight. Under the MOU, Hawaii Gas is responsible for developing the on and near-shore infrastructure to support larger-scale LNG delivery in Hawaii in the most cost efficient and least impactful manner.

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Hawaii Gas Strategy

Hawaii Gas’ strategy has four primary components:

Recent Developments

BEC Acquisition

On January 28, 2015, we signed a purchase and sale agreement for the purchase of 100% of BEC for a purchase price of $720.0 million, which we refer to as the BEC Acquisition, which consists of approximately $210.0 million in cash and the assumption of approximately $510.0 million of debt, excluding transaction costs. We intend to use a portion of the net proceeds from this offering to finance the cash consideration for the BEC Acquisition, including any related fees and expenses. Following the acquisition, we intend to refinance all or a portion of the assumed debt, subject to market conditions, with drawings under available credit facilities and cash on hand. See “Use of Proceeds.”

BEC is a 512 megawatt natural gas-fired electric generating facility, comprising eight Rolls Royce natural gas-fired aeroderivative turbines and commenced operations in 2012. The BEC facility is located immediately adjacent to IMTT. Power produced by BEC is transmitted via a dedicated cable beneath New York Harbor to a substation in Brooklyn, New York from which it is distributed throughout the New York City power market. 62.5% of the facility’s capacity is contracted with a creditworthy power wholesaler through tolling agreements, which have a weighted average remaining term of approximately 13 years. In addition to the tolling agreement revenue, BEC receives capacity payments from the grid operator and generates energy margin when the facility is dispatched. Assuming consummation of the BEC Acquisition, we expect our CP&E segment to generate approximately 15% of MIC’s earnings before interest, taxes, depreciation and amortization, or EBITDA, excluding non-cash items. We believe that BEC’s proximity to IMTT’s Bayonne, New Jersey facility provides an opportunity to pursue growth opportunities including (i) developing up to an additional 100 megawatts of generating capacity on undeveloped IMTT land; (ii) capturing operating synergies between BEC and IMTT; and (iii) using IMTT’s facilities for backup fuel storage capacity.

We currently expect underlying 2015 Free Cash Flow per share, assuming the BEC Acquisition is consummated and excluding transaction-related expenses, to increase approximately 14% compared to 2014, subject to general economic conditions and the continued stable performance of our businesses. We currently expect Free Cash Flow accretion from the BEC Acquisition of approximately $0.26 per share on an annualized basis.

We report Free Cash Flow, as defined below, as a means of assessing the amount of cash generated by our businesses and as a supplement to other information provided in accordance with GAAP. We believe that reporting Free Cash Flow provides additional insight into our ability to deploy cash, as GAAP measures, such as net income (loss) and cash from operating activities, do not reflect all of the items that our management considers in estimating the amount of cash generated by our operating businesses. We define Free Cash Flow as cash from operating activities, including cash paid for interest, taxes and pension contributions, less maintenance capital expenditures, which includes principal repayments on capital lease obligations used to fund maintenance capital expenditures, and excludes changes in working capital. Free Cash Flow does not fully reflect our ability to freely deploy generated cash, as it does not reflect required payments to be made on our indebtedness and other fixed obligations or the other cash items excluded when calculating Free Cash Flow. Free Cash Flow may be calculated in a different manner by other companies, which limits its usefulness as a comparative measure. Therefore, Free Cash Flow should be used as a supplemental measure and not in lieu of our financial results as reported under GAAP.

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We expect the BEC Acquisition to close during the first half of 2015, subject to receipt of regulatory approvals and satisfaction of customary closing conditions. There can be no assurance that the BEC Acquisition will be consummated in a timely manner or at all or that any anticipated results, opportunities or synergies in connection with BEC will be realized. See the risk factors and other cautionary statements under the headings “Forward-Looking Statements” and “Risk Factors” in this prospectus supplement and in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 for a description of risks and uncertainties that could affect our ability to achieve estimated results or realize any synergies.

Proposed Conversion and Authorization of Preferred Stock

On February 17, 2015, our Board of Directors approved a plan of conversion, including a form of certificate of incorporation and form of bylaws contemplated thereby (the “Conversion”), providing for our proposed conversion from a limited liability company organized under the laws of the State of Delaware to Macquarie Infrastructure Corporation, a corporation organized under the laws of the State of Delaware, (“MIC Corp.”). If the Conversion is consummated, each outstanding limited liability company interest of MIC LLC will be converted into one share of common stock, par value, $0.001 per share, of MIC Corp. Concurrently with the Conversion, our Manager will be issued 100 shares of special stock, par value $0.001 per share, of MIC Corp. The sole purpose for the issuance of special stock to our Manager is to preserve our Manager’s existing right to appoint one director who serves as the chairman of the board of MIC, which right would otherwise be lost upon consummation of the Conversion. Following the Conversion and the issuance of special stock, our Manager’s right to elect one director will be the same as is currently in effect. We are not granting any additional rights to our Manager through the special stock issuance.

Our Board of Directors has also approved the authorization of 100,000,000 shares of preferred stock, par value $0.001 per share, which may be issued from time to time, conditioned on the approval of our shareholders and the consummation of the Conversion (the “Preferred Stock Proposal”). If the Preferred Stock Proposal is consummated, the consent or our Manager, as the holder of our shares of special stock, will be required in order for us to issue preferred stock.

The Conversion will not be consummated unless it is approved by the holders of a majority of our shares outstanding and entitled to vote thereon. The Conversion is also conditioned on, among other things, approval for listing on the NYSE of the shares of common stock to be issued in connection with the Conversion and the effectiveness of a registration statement on Form S-4, which we filed with the SEC for the purpose of registering the shares of common stock to be issued in the Conversion. The Preferred Stock Proposal will not be consummated unless (i) it is approved by the holders of a majority of our shares outstanding and entitled to vote thereon and (ii) the Conversion is consummated. There can be no assurance as to whether or when the Conversion or the Preferred Stock Proposal will be consummated.

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THE OFFERING

Except as otherwise noted, all information in this prospectus supplement assumes that the underwriters’ option to purchase additional shares is not exercised.

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SUMMARY FINANCIAL DATA

The summary financial data includes the results of operations, cash flow and balance sheet data for the years ended December 31, 2014, 2013 and 2012 for our consolidated group, with the results of businesses acquired during those years being included from the date of each acquisition. The summary financial data for each of the three years in the period ended December 31, 2014 have been derived from our consolidated financial statements, which financial statements have been audited by KPMG LLP.

The unaudited pro forma consolidated statement of operations data set forth below gives effect to the IMTT Acquisition and the related equity and convertible senior notes offerings and use of proceeds therefrom, or the Transactions, as if they had occurred as of January 1, 2014. The pro forma adjustments give effect to the Transactions based upon the acquisition method of accounting in accordance with U.S. generally accepted accounting principles, or GAAP, and upon the assumptions set forth in the notes to the unaudited pro forma consolidated statement of operations incorporated by reference herein. The unaudited pro forma consolidated statement of operations data is presented for illustrative purposes only and is not necessarily indicative of the results of operations of future periods or the results of operations that actually would have been realized had we and IMTT been consolidated during the entire period presented. The pro forma adjustments have been prepared to illustrate the estimated effect of the acquisition and certain other adjustments and based on certain assumptions as explained in more detail in the notes to the unaudited pro forma consolidated statement of operations incorporated by reference herein.

The information below should be read in conjunction with (i) our consolidated financial statements (and notes thereto), (ii) the unaudited consolidated financial statements (and notes thereto) of IMTT Holdings Inc. and Subsidiaries for the period ended July 15, 2014, which are included as an exhibit to our Annual Report on Form 10-K for the year ended December 31, 2014 and incorporated by reference herein, (iii) the consolidated financial statements (and notes thereto) of IMTT Holdings Inc. and Subsidiaries for the years ended December 31, 2013 and December 31, 2012, which are included as an exhibit to our Annual Report on Form 10-K for the year ended December 31, 2014 and incorporated by reference herein, (iv) the unaudited pro forma combined consolidated statement of operations (and notes thereto) for the year ended December 31, 2014 contained in our Current Report on Form 8-K filed with the SEC on February 24, 2015 and (v) “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Part II, Item 7 in our Annual Report on Form 10-K for the year ended December 31, 2014, incorporated by reference herein.

		Macquarie Infrastructure Company LLC
		Year Ended December 31,												Pro Forma Year Ended December 31, 2014
		2014				2013				2012				(unaudited)
		($ in thousands, except shares and per share data)
Statement of operations data:
Revenue
Service revenue		$	1,064,682			$	770,360			$	768,617			$	1,376,215
Product revenue			284,400				267,096				260,893				284,400
Financing and equipment lease income			1,836				3,563				4,536				1,836
Total revenue			1,350,918				1,041,019				1,034,046				1,662,451
Cost of revenue
Cost of services(1)			546,609				434,177				448,993				686,689
Cost of product sales			192,881				185,843				188,099				192,881
Gross profit			611,428				420,999				396,954				782,881
Selling, general and administrative expenses			265,254				210,060				213,372				272,552
Fees to manager-related party			168,182				85,367				89,227				168,182
Depreciation			98,442				39,150				31,587				159,764
Amortization of intangibles			42,695				34,651				34,601				48,718
Loss from customer contract termination			1,269				5,906				—				1,269
Loss (gain) on disposal of assets(2)			1,279				226				(1,358	)			1,279
Total operating expenses			577,121				375,360				367,429				651,764

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		Macquarie Infrastructure Company LLC
		Year Ended December 31,												Pro Forma Year Ended December 31, 2014
		2014				2013				2012				(unaudited)
		($ in thousands, except shares and per share data)
Operating income			34,307				45,639				29,525				131,117
Dividend income			1,344				—				—				2,809
Interest income			112				204				222				112
Interest expense(3)			(73,196	)			(37,044	)			(46,623	)			(96,599	)
Loss on extinguishment of debt			(90	)			(2,472	)			—				(90	)
Equity in earnings and amortization charges of investee			26,391				39,115				32,327				244
Gain from acquisition/divestiture of businesses(4)			1,027,054				—				—				78,917
Other (expense) income, net			(1,013	)			681				1,085				(500	)
Net income before income taxes			1,014,909				46,123				16,536				116,010
Benefit (provision) for income taxes			24,374				(18,043	)			(2,285	)			(40,603	)
Net income		$	1,039,283			$	28,080			$	14,251			$	75,407
Less: net (loss) income attributable to noncontrolling interests			(2,745	)			(3,174	)			930				(2,516	)
Net income attributable to MIC LLC		$	1,042,028			$	31,254			$	13,321			$	77,923
Per Share Data:
Basic income per share attributable to MIC LLC		$	16.54			$	0.61			$	0.29			$	1.11
Weighted average number of shares outstanding: basic(5)			62,990,312				51,381,003				46,635,049				70,062,770
Diluted income per share attributable to MIC LLC		$	16.10			$	0.61			$	0.29			$	1.11
Weighted average number of shares outstanding: diluted(5)(6)			64,925,565				51,396,146				46,655,289				74,203,377
Cash dividends declared per share		$	3.8875			$	3.35			$	2.20			$	3.8875

		As of December 31,
		2014				2013				2012
		($ in thousands)
Balance sheet data:
Total current assets		$	256,890			$	406,550			$	253,910
Property, equipment, land and leasehold improvements, net			3,362,585				854,169				708,031
Intangible assets, net			959,634				592,850				626,902
Goodwill			1,996,259				514,494				514,640
Total assets		$	6,625,188			$	2,500,865			$	2,223,694
Total current liabilities		$	224,332			$	271,452			$	245,330
Deferred income taxes			904,108				189,719				169,392
Long-term debt, net of current portion			2,364,866				831,027				1,052,584
Total liabilities			3,655,020				1,347,597				1,526,129
Members’ equity		$	2,787,163			$	1,042,228			$	655,028

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RISK FACTORS

An investment in our shares involves a number of risks. We urge you to carefully consider the risk factors described below and those included in the accompanying prospectus and in the documents incorporated herein and therein by reference, including our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 as well as other information, before reaching a decision regarding an investment in our shares. For risks related to our business operations, see “Risk Factors — Risks Related to our Business Operations,” “Risk Factors — Risks Related to IMTT,” “Risk Factors — Risks Related to Atlantic Aviation,” “Risk Factors — Risks Related to CP&E” and “Risk Factors — Risks Related to Hawaii Gas” in our Annual Report on Form 10-K for the year ended December 31, 2014. The risks described below and referenced above are not the only risks we face. Additional risks not presently known to us or that we currently deem immaterial may also impair our business operations. If any of the risks described herein or cross-referenced above were to materialize, our business, results of operations, cash flow, financial condition and prospects could be materially and adversely affected. In that case, our ability to pay dividends to our shareholders may be reduced, the trading price of our shares could decline and you could lose all or part of your investment. You should consult your own financial and legal advisors before making an investment in our shares.

Risks Related to this Offering

Future sales of our shares could adversely affect the market price.

Following this offering, we will have a large number of shares outstanding and available for resale. Sales by us or our shareholders of a substantial number of our shares in the public market after this offering, or the possibility that these sales may occur, could cause the market price for our shares to decline. These sales, or the possibility that these sales may occur, could also make it more difficult for us to sell our shares or other equity securities in the future at a time and at a price that we deem appropriate. Pursuant to a registration rights agreement, our Manager has the right to require us to register for resale with the SEC the shares that it owns and to include its shares in future registered offerings that we may conduct. After this offering, 76,544,284 of our shares (77,341,159 if the underwriters’ option to purchase additional shares is exercised in full but, in each case, excluding (i) 12,525 shares issuable upon vesting of the same number of outstanding restricted stock units and (ii) 994,096 shares reserved for issuance under our Direct Stock Purchase and Dividend Reinvestment Program) will be outstanding, most of which are freely transferable without restriction or further registration under the federal securities laws, except for any shares held by our affiliates, sales of which will be limited by Rule 144 under the Securities Act of 1933, as amended, or the Securities Act, absent registration under the Securities Act.

Risks Related to Having an External Manager

We are subject to the terms and conditions of the management services agreement between us and our Manager.

We cannot unilaterally amend the Management Services Agreement between us and our Manager. Changes in the compensation of our Manager, certain rights held by our Manager or other components of the management services agreement require the approval of our Manager and may limit our ability to make changes that could be beneficial to shareholders generally.

Our Manager owns a significant portion of our outstanding shares. A sale of all or a portion of the shares owned by our Manager could be interpreted by the equity markets as a lack of confidence in our prospects.

Our Manager, in its sole discretion, determines whether to reinvest base management and performance fees in shares and whether to hold or sell those securities. Reinvestment of base management and performance fees in additional shares would increase our Manager’s ownership stake in us. As of February 25, 2015, our Manager owned 6.75% of our outstanding shares. If our Manager decides, for reasons other than our performance and prospects to reduce its position in us, such sales may be interpreted by some market participants as a lack of confidence in us and put downward pressure on the market price of our shares. Sales of shares by our Manager could increase the available supply and decrease the price if such sales are not made in an orderly fashion.

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Certain provisions of our management services agreement and operating agreement make it difficult for third parties to acquire control of us and could deprive investors of the opportunity to obtain a takeover premium for their shares.

In addition to the limited circumstances in which our Manager can be terminated under the terms of the management services agreement, the management services agreement provides that in circumstances where the shares cease to be listed on a recognized U.S. exchange as a result of the acquisition of our shares by third parties in an amount that results in the shares ceasing to meet the distribution and trading criteria on such exchange or market, our Manager has the option to either propose an alternate fee structure and remain our Manager or resign, terminate the management services agreement upon 30 days’ written notice and be paid a substantial termination fee. The termination fee payable on our Manager’s exercise of its right to resign as our Manager subsequent to a delisting of our shares could delay or prevent a change in control that may favor our shareholders. Furthermore, in the event of such a delisting, any proceeds from the sale, lease or exchange of a significant amount of assets must be reinvested in our new assets, subject to debt repayment obligations. We would also be prohibited from incurring any new indebtedness or engaging in any transactions with our shareholders or our affiliates’ shareholders without the prior written approval of our Manager. These provisions could deprive shareholders of opportunities to realize a premium on the shares owned by them.

Our operating agreement, which we refer to as the LLC agreement, contains a number of provisions that could have the effect of making it more difficult for a third-party to acquire, or discouraging a third-party from acquiring, control of us. These provisions include:

If the Conversion is consummated, our certificate of incorporation and bylaws will contain similar provisions.

Our Manager’s decision to reinvest its monthly base management fees and quarterly performance fees, as applicable, in shares or retain the cash will affect shareholders differently.

Our Manager earned $46.6 million and $121.5 million in base management and performance fees, respectively, during 2014. These fees are based on our market capitalization and performance and may be higher or lower than these levels in the future. Our Manager, in its sole discretion, may elect to retain base management fees and performance fees, if applicable, paid in cash or to reinvest such payments in additional shares. In the event our Manager chooses not to reinvest the fees to which it is entitled in additional shares, the amount paid will reduce the cash that may otherwise be distributed as a dividend to all shareholders or used in our operations. In the event our Manager chooses to reinvest the fees to which it is entitled in additional shares, effectively returning the cash to us, such reinvestment will dilute existing shareholders by the increase in the percentage of shares owned by our Manager. Either option may adversely impact the market for our shares.

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In addition, our Manager has typically elected to invest its fees in shares, and, unless otherwise agreed with us, can only change this election during an 18-trading day window following our earnings release. Any change would apply to fees paid thereafter. Accordingly, shareholders would generally have notice of our Manager’s intent to receive fees in cash rather than reinvest before the change is effective.

Our Manager can resign with 90 days’ notice, or our CEO or CFO could be removed by the Manager, and we may not be able to find a suitable replacement within that time, resulting in a disruption in our operations, which could adversely affect our financial results and negatively impact the market price of our shares.

Our Manager has the right, under the management services agreement, to resign at any time with 90 days’ notice, whether we have found a replacement or not. The resignation of our Manager will trigger mandatory repayment obligations under debt facilities at certain of our operating companies. In addition, our Manager could re-assign or remove the CEO and/or the CFO from their positions and responsibilities without our Board of Directors’ approval and with little or no notice. If our Manager resigns or our CEO/CFO are removed, we may not be able to find a new external manager or hire internal management with similar expertise within 90 days to provide the same or equivalent services on acceptable terms, or at all. If we are unable to do so quickly, our operations are likely to experience a disruption, our financial results could be adversely affected, perhaps materially, and the market price of our shares may decline substantially. In addition, the coordination of our internal management, acquisition activities and supervision of our businesses are likely to suffer if we were unable to identify and reach an agreement with a single institution or group of executives having the expertise possessed by our Manager and its affiliates.

Furthermore, if our Manager resigns, we and our subsidiaries will be required to cease use of the Macquarie brand entirely, and change their names to remove any reference to “Macquarie.” This may cause the value of our Company and the market price of our shares to decline.

Our externally managed model may not be viewed favorably by investors.

We are externally managed by a member of the Macquarie Group. Our Manager receives a fee for its services that provides for a number of corporate center functions including the compensation of our management team and those who provide services to us on a shared basis, health and welfare benefits, the provision of facilities, technology and insurance (other than directors and officers). The fee is based on our market capitalization and thus increases as we grow. The size of the fee may bear no direct correlation with the actual cost of providing the agreed upon services and may be higher than the cost of managing our Company internally. Per the terms of the management services agreement with our Manager, the default manner for satisfying any base management or performance fees to which our Manager may be entitled is the issuance of additional shares. To the extent the fee continues to be satisfied with the delivery of additional shares, all shareholders are diluted and our hurdle for growing distributable cash on a per share basis will be higher.

Our Manager’s affiliation with Macquarie Group Limited and the Macquarie Group may result in conflicts of interest or a decline in our share price.

Our Manager is an affiliate of Macquarie Group Limited and a member of the Macquarie Group. From time to time, we have entered into, and in the future we may enter into, transactions and relationships involving Macquarie Group Limited, its affiliates, or other members of the Macquarie Group. Such transactions have included and may include, among other things, the entry into debt facilities and derivative instruments with members of the Macquarie Group serving as lender or counterparty, and financial advisory or equity underwriting services provided to us by the Macquarie Group.

Although our audit committee, all of the members of which are independent directors, is required to approve of any related party transactions, including those involving members of the Macquarie Group or its affiliates, the relationship of our Manager to the Macquarie Group may result in conflicts of interest.

In addition, because our Manager is a member of the Macquarie Group, negative market perceptions of Macquarie Group Limited generally or of Macquarie’s infrastructure management model, or Macquarie Group statements or actions with respect to other managed vehicles, may affect market perceptions of us and cause a decline in the price of our shares unrelated to our financial performance and prospects.

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In the event of the underperformance of our Manager, we may be unable to remove our Manager, which could limit our ability to improve our performance and could adversely affect the market price of our shares.

Under the terms of the management services agreement, our Manager must significantly underperform in order for the management services agreement to be terminated. Our Board of Directors cannot remove our Manager unless:

Because our Manager’s performance is measured by the market performance of our shares relative to a benchmark index, even if the absolute market performance of our shares does not meet expectations, our Board of Directors cannot remove our Manager unless the market performance of our shares also significantly underperforms the benchmark index. If we were unable to remove our Manager in circumstances where the absolute market performance of our shares does not meet expectations, the market price of our shares could be negatively affected.

Risks Related to Ownership of Our Shares

Our reported Earnings per Share, or EPS, as defined under GAAP, do not reflect the cash generated by our businesses and may result in unfavorable comparisons with other businesses for which EPS is a useful component in valuation.

Our businesses own and invest in high-value, long-lived assets that generate large amounts of depreciation and amortization. Depreciation and amortization are non-cash expenses that serve to reduce reported EPS. As a result, our financial performance may appear to be substantially worse compared with businesses whose earnings do not reflect the effects of depreciation and amortization (or other non-cash items). To the extent that our results appear to be worse, we may have relatively greater difficulty attracting investors in our shares.

Our inability, under GAAP, to consolidate the financial results of certain of our investments may make it relatively more difficult to analyze the cash generating capacity of our combined businesses.

We may make investments in certain businesses which we will be required to account for using the equity method rather than consolidate with the results of our other businesses. The equity method requires us to include the portion of the net income, as determined in accordance with GAAP, equal to our equity interest in the business in our consolidated statement of operations. The physical asset backed nature of the businesses in which we invest (and the higher levels of non-cash expenses including depreciation and amortization) may mean that the performance of these investments have relatively little impact on our consolidated statement of operations and may not be reflected in the valuation of our shares.

We report dividends, whether treated as dividends or returns of capital for federal income tax purposes, on Form 1099, but could report on Schedule K-1 in the future.

Our Company is structured as a limited liability company that has made an election to be treated as a regular corporation for tax purposes. We report distributions to shareholders on Form 1099, either in Box 1 as a dividend or in Box 3 as a return of capital, depending on the level of earnings and profits generated in the

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reporting period. We may not always be or be treated as a corporation in which case distributions may be reported on another tax form including possibly Schedule K-1. Certain investors may not wish to or may be precluded from investing in an entity that reports on Schedule K-1 thus limiting the market for our shares.

Our total assets include a substantial amount of goodwill and other intangible assets. The write-off of a significant portion of intangible assets would negatively affect our reported earnings.

Our total assets reflect a substantial amount of goodwill and other intangible assets. At December 31, 2014, goodwill and other intangible assets, net, represented approximately 44.6% of total assets. Goodwill and other intangible assets were primarily recognized as a result of the acquisitions of our businesses. Other intangible assets consist primarily of airport operating rights, customer relationships and trade names. On at least an annual basis, we assess whether there has been any impairment in the value of goodwill and assess for impairment of other intangible assets when there are triggering events or circumstances. If the carrying value of the tested asset exceeds its estimated fair value, impairment is deemed to have occurred. In this event, the amount is written down to fair value. Under current accounting rules, this would result in a charge to reported earnings. We have recognized significant impairments in the past, and any future determination requiring the write-off of a significant portion of goodwill or other intangible assets would negatively affect our reported earnings and total capitalization, and could be material.

Our total assets include a substantial amount of intangible assets and fixed assets. The depreciation and amortization of these assets may negatively impact our reported earnings.

The high level of intangible and physical assets written up to fair value upon acquisition of our businesses generates substantial amounts of depreciation and amortization. These non-cash items serve to lower net income as reported in our consolidated statement of operations as well as our taxable income. The generation of net losses or relatively small net income may contribute to a net operating loss, or NOL, carryforward that can be used to offset current taxable income in future periods. However, the continued reporting of little or negative net income may adversely affect the attractiveness of our Company among some potential investors and may reduce the market for our shares.

The market price and marketability of our shares may from time to time be significantly affected by numerous factors beyond our control, which may adversely affect our ability to raise capital through future equity financings.

The market price of our shares may fluctuate significantly. Many factors that are beyond our control may significantly affect the market price and marketability of our shares and may adversely affect our ability to raise capital through equity financings. These factors include, but are not limited to, the following:

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Risks Related to Taxation

We have significant NOL carryforwards that may be fully utilized over the next several years thereby subjecting us to payment of substantial U.S. federal income taxes and reducing our distributable Free Cash Flow.

We may, without the acquisition of businesses with NOLs, payment of performance fees or implementation of other strategies that provide us with additional tax shield, fully utilize our existing NOLs before we anticipate or have previously indicated. At that point, we may be subject to U.S. federal income taxes in consolidation and any liability could be material. Any liability will reduce distributable Free Cash Flow and could prevent the growth or reduce the rate of growth of our dividends.

The current treatment of qualified dividend income and long-term capital gains under current U.S. federal income tax law may be adversely affected, changed or repealed in the future.

Under current law, qualified dividend income and long-term capital gains are taxed to non-corporate investors at a maximum U.S. federal income tax rate of 20%. In addition, certain holders that are individuals, estates or trusts are subject to 3.8% surtax on all or a portion of their “net investment income,” which may include all or a portion of their dividend income and net gains from the disposition of our shares. This tax treatment may be adversely affected, changed or repealed by future changes in tax laws at any time, which may affect market perceptions of our Company and the market price of our shares could be negatively affected.

Our ability to use our NOL carryforwards to offset future taxable income may be subject to certain limitations.

In general, under Section 382 of the Internal Revenue Code of 1986, as amended, or the Code, a corporation (or other entity taxable as a corporation, such as us) that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change NOLs and certain other tax attributes to offset future taxable income. Generally speaking, an “ownership change” occurs if the aggregate percentage ownership of the stock of the corporation held by one or more “five-percent shareholders” (as defined in the Code and the Treasury regulations promulgated thereunder, or the Regulations) increases by more than fifty percentage points over such shareholders’ lowest percentage ownership during the testing period, which is generally the three year-period ending on the transaction date. If we undergo an ownership change, our ability to utilize NOLs and certain other tax attributes could be limited.

We have significant income tax NOLs, which may not be realized before they expire.

We have $250.7 million in federal NOL carryforwards at December 31, 2014. While we have concluded that all of the NOLs will more likely than not be realized, there can be no assurance that we will utilize the NOLs generated to date or any NOLs we might generate in the future. In addition, we have incurred state NOLs and have provided a valuation allowance against a portion of those. As with our federal NOLs, there is also no assurance that we will utilize those state losses or future losses that may be generated. Further, the State of Illinois has suspended the use of NOL carryforwards through 2014, similar to the State of California’s suspension of an NOL deduction through 2011 for large corporations. There can be no assurance that other states will not suspend the use of NOL carryforwards or that California and Illinois will not extend the suspension of the use of NOL carryforwards.

The treatment of depreciation and other tax deductions under current U.S. federal income tax law may be adversely affected, changed or repealed in the future.

Under current law, certain capital expenditures are eligible for accelerated depreciation, including 50% bonus depreciation for assets placed in service prior to December 31, 2014, for U.S. federal income tax purposes. In addition, certain other expenses are eligible to be deducted for U.S. federal income tax purposes. This tax treatment may be adversely affected, changed or repealed by future changes in tax laws at any time, which may affect market perceptions of us, and the market price of our shares could be negatively affected.

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Risks Related to the Conversion

If the Conversion is consummated, the benefits expected to be obtained from the Conversion may not be achieved.

If the Conversion is consummated, the benefits expected to be obtained from the Conversion may not be achieved. For example, the Conversion may not result in our inclusion in certain stock market indices, such as the S&P indices and the Russell indices that we may be eligible for as a corporation following the Conversion. Inclusion in such indices may not result in an increased demand for our securities, and we may not have greater access to capital. The Conversion also may not increase our ability to retain our current directors or attract and retain new directors.

The Conversion may not be consummated on a timely basis or at all. Failure to consummate the Conversion could negatively impact the market price of the shares and our future business and financial results.

We cannot assure you that the Conversion will be approved by our shareholders or that the other conditions to the consummation of the Conversion will be satisfied or waived. If the Conversion is not consummated, we will not receive any of the expected benefits of the Conversion and will be subject to risks and/or liabilities, including the following:

The rights of holders of our shares who become holders of common stock upon the effective time of the Conversion will be governed by our new certificate of incorporation and bylaws, and certain rights of holders of common stock may be less favorable than those rights granted to holders of our shares pursuant to our current operating agreement.

Holders of our shares who receive common stock in the Conversion will become subject to the General Corporation Law of the State of Delaware, and will be governed by our certificate of incorporation and bylaws, rather than our current operating agreement. As a result, there will be differences between the current rights of the holders of shares under the operating agreement, as compared to the rights they will have as holders of common stock under the certificate of incorporation and the bylaws, and certain rights of holders of common stock may be less favorable than those rights granted to holders of our shares. For example, the certificate of incorporation states that the Court of Chancery of the State of Delaware will be the sole and exclusive forum to bring derivative claims, fiduciary claims and internal affairs actions.

If the Preferred Stock Proposal is consummated, preferred stock could be issued with rights, preferences and privileges that may be superior to the common stock, and could have other negative consequences to holders of common stock.

If the Conversion and the Preferred Stock Proposal are consummated, shares of preferred stock could be issued in one or more financing transactions. We could also use the authorized preferred stock for potential strategic transactions, including, among other things, acquisitions, strategic partnerships, joint ventures, restructurings, business combinations and investments, although we have no immediate plans to do so. There are no assurances that any such transactions will be consummated on favorable terms or at all, that they will enhance shareholder value, or that they will not adversely affect our business or the trading price of the common stock. Any shares of preferred stock could be issued with rights, preferences and privileges that may be superior to those of the common stock. In addition, preferred stock could be issued for capital raising, financing and acquisition needs or opportunities that have the effect of making an acquisition of our Company more difficult or costly, as could also be the case if the board of directors were to issue additional common stock.

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USE OF PROCEEDS

We estimate that our net proceeds from this offering, after underwriting discounts and estimated offering expenses, will be approximately $410.7 million (approximately $472.4 million if the underwriters’ option to purchase additional shares is exercised in full). We intend to use a portion of the net proceeds to us from this offering to finance the cash consideration for the BEC Acquisition, including any related fees and expenses. See “Prospectus Supplement Summary — Recent Developments — BEC Acquisition.” We intend to use the remaining portion of the net proceeds to us from this offering for general corporate purposes. There can be no assurance that we will be able to consummate the BEC Acquisition on a timely basis or at all and, if the BEC Acquisition is not consummated, we intend to use the net proceeds to us from this offering for general corporate purposes and for fees and expenses related to the BEC Acquisition that are payable whether or not it is consummated. In the event of the exercise of the underwriters’ option to purchase additional shares in this offering, we intend to use the proceeds in respect of such additional shares for general corporate purposes.

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CAPITALIZATION

The following sets forth (i) our actual capitalization as of December 31, 2014 and (ii) our capitalization, as adjusted, as of December 31, 2014 giving effect to the offering and the receipt of the net proceeds to us. You should read this table in conjunction with other sections of this prospectus supplement, the accompanying prospectus and any documents that are incorporated by reference herein and therein, including our consolidated financial statements and the notes thereto.

		As of December 31, 2014
($ in thousands, except share data)		Actual				As Adjusted(1)(2)
Cash and cash equivalents		$	48,014			$	459,202
Long-term debt, net of current portion		$	2,364,866			$	2,364,866
Total debt (current and non-current)			2,392,521				2,392,521
Members’ Equity
LLC interests, no par value:
500,000,000 authorized; 71,089,590 issued and outstanding, actual(3); 76,544,284 issued and outstanding, as adjusted		$	1,942,745			$	2,353,933
Additional paid in capital			21,447				21,447
Accumulated other comprehensive loss			(21,550	)			(21,550	)
Retained earnings			844,521				844,521
Total members’ equity			2,787,163				3,198,351
Noncontrolling interests			183,005				183,005
Total equity			2,970,168				3,381,356
Total Capitalization		$	5,362,689			$	5,773,877

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MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS

The following discussion describes the material U.S. federal income tax considerations associated with the purchase, ownership and disposition of our shares by U.S. holders (as defined below) and non-U.S. holders (as defined below). Except where noted, this discussion deals only with our shares held as capital assets by holders who acquired our shares in this issuance and does not address special situations, such as those of:

Furthermore, the discussion below is based upon the provisions of the Code, the Regulations and administrative and judicial interpretations thereof, all as of the date hereof, and such authorities may be repealed, revoked, modified or subject to differing interpretations, possibly on a retroactive basis, so as to result in U.S. federal income tax consequences different from those described below.

A “U.S. holder” of our shares means a beneficial owner of our shares that is for U.S. federal income tax purposes:

A “non-U.S. holder” of our shares means a beneficial owner of our shares that is an individual, a corporation, an estate or a trust that is neither a U.S. holder nor a partnership (or other entity taxable as a partnership).

If a partnership or other entity or arrangement treated as a partnership for U.S. federal income tax purposes holds our shares, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. If you are a partner of a partnership holding our shares, we urge you to consult your own tax adviser.

We cannot assure you that the IRS or the courts will agree with the tax consequences described herein.

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A different treatment from that described below could adversely affect the amount, timing and character of income, gain or loss in respect of an investment in our shares. If you are considering the purchase of our shares, we urge you to consult your own tax adviser concerning the particular U.S. federal income tax consequences to you of the purchase, ownership and disposition of our shares, as well as any consequences to you arising under the laws of any other taxing jurisdiction.

U.S. Holders

The following discussion summarizes the material U.S. federal income tax consequences of the ownership and disposition of our shares applicable to U.S. holders, subject to the limitations described above.

No Flow-Through of Taxable Income

An election has been made with the IRS to treat us as an association taxable as a corporation for U.S. federal income tax purposes. Because we are treated as an association taxable as a corporation for U.S. federal income tax purposes, an owner of our shares will not report on its U.S. federal income tax return any of our items of income, gain, loss or deduction.

Distributions

Distributions of cash or property that we pay in respect of our shares will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits (as determined under U.S. federal income tax principles) and will be includible in gross income by a U.S. holder upon receipt. Any such dividend will be eligible for the dividends received deduction if received by an otherwise qualifying corporate U.S. holder that meets the holding period and other requirements for the dividends received deduction. Dividends paid by us to certain non-corporate U.S. holders (including individuals) are eligible for U.S. federal income taxation at the rates generally applicable to long-term capital gains for individuals (at a maximum tax rate of 20%), provided that the U.S. holder receiving the dividend satisfies the applicable holding period and other requirements. If the amount of a distribution exceeds our current and accumulated earnings and profits, such excess first will be treated as a return of capital to the extent of the U.S. holder’s tax basis in our shares, and thereafter will be treated as capital gain.

Dispositions

Upon a sale, exchange or other taxable disposition of our shares, a U.S. holder generally will recognize capital gain or loss equal to the difference between the amount realized on the sale, exchange or other taxable disposition and the U.S. holder’s adjusted tax basis in our shares. Such capital gain or loss will be long-term capital gain or loss if the U.S. holder has held our shares for more than one year at the time of disposition. Long-term capital gains of certain non-corporate U.S. holders (including individuals) are subject to U.S. federal income taxation at a maximum rate of 20%. The deductibility of capital losses is subject to limitations under the Code.

Medicare Tax on Investment Income

Certain U.S. holders who are individuals, estates, or trusts will be subject to a 3.8% Medicare tax on the lesser of (1) the U.S. holder’s “net investment income” for the relevant taxable year and (2) the excess of the U.S. holder’s modified adjusted gross income for the taxable year over a certain threshold (which in the case of individuals will be between $125,000 and $250,000, depending on the individual’s circumstances). A U.S. holder’s net investment income will generally include its dividend income and its gains from the disposition of our shares, unless such dividend income or gains are derived in the ordinary course of the conduct of a trade or business (other than a trade or business that consists of certain passive or trading activities). If you are a U.S. holder that is an individual, estate, or trust, you are urged to consult your own tax advisors regarding the applicability of the Medicare tax to your income and gains in respect of your investment in our shares.

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Information Reporting and Backup Withholding Requirements

In general, dividends on our shares, and payments of the proceeds of a sale, exchange or other taxable disposition of our shares paid to a U.S. holder are subject to information reporting and may be subject to backup withholding at a rate of 28% unless the U.S. holder (i) is a corporation or other exempt recipient or (ii) provides an accurate taxpayer identification number and certifies that it is not subject to backup withholding.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a U.S. holder will be refunded by the IRS or credited against the U.S. holder’s U.S. federal income tax liability, if any, provided that the required information is furnished to the IRS.

Non-U.S. Holders

The following discussion summarizes the material U.S. federal income tax consequences of the ownership and disposition of our shares applicable to non-U.S. holders, subject to the limitations described above.

U.S. Trade or Business Income

For purposes of this discussion, dividend income and gain on the sale, exchange or other taxable disposition of our shares will be considered to be “U.S. trade or business income” if such income or gain is (i) effectively connected with the conduct by a non-U.S. holder of a trade or business within the United States and (ii) in the case of a non-U.S. holder that is eligible for the benefits of an income tax treaty with the United States, attributable to a permanent establishment (or, for an individual, a fixed base) maintained by the non-U.S. holder in the United States. Generally, U.S. trade or business income is not subject to U.S. federal withholding tax (provided the non-U.S. holder complies with applicable certification and disclosure requirements); instead, a non-U.S. holder is subject to U.S. federal income tax on a net income basis at regular graduated U.S. federal income tax rates (in the same manner as a U.S. person) on its U.S. trade or business income. Any U.S. trade or business income received by a non-U.S. holder that is a corporation also may be subject to a “branch profits tax” at a 30% rate (or lower treaty rate, if applicable) on its effectively connected earnings and profits that are not timely reinvested in a U.S. trade or business.

Distributions

Subject to the discussion below under the heading “FATCA Withholding”, distributions of cash or property that we pay in respect of our shares will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits (as determined under U.S. federal income tax principles). A non-U.S. holder generally will be subject to U.S. federal withholding tax at a 30% rate, or at a reduced rate prescribed by an applicable income tax treaty, on any dividends received in respect of our shares. If the amount of a distribution exceeds our current and accumulated earnings and profits, such excess first will be treated as a tax-free return of capital to the extent of the non-U.S. holder’s tax basis in our shares, and thereafter will be treated as capital gain (and thus treated in the manner described in “— Dispositions” below). In order to obtain a reduced rate of U.S. federal withholding tax under an applicable income tax treaty, a non-U.S. holder will be required to provide a properly executed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, certifying its entitlement to benefits under the treaty. A non-U.S. holder of our shares that is eligible for a reduced rate of U.S. federal withholding tax under an income tax treaty may obtain a refund or credit of any excess amounts withheld by filing an appropriate claim for a refund with the IRS. A non-U.S. holder should consult its own tax advisor regarding its possible entitlement to benefits under an income tax treaty.

The U.S. federal withholding tax described in the preceding paragraph does not apply to dividends that represent U.S. trade or business income of a non-U.S. holder who provides a properly executed IRS Form W-8ECI, certifying that the dividends are effectively connected with the non-U.S. holder’s conduct of a trade or business within the United States.

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Dispositions

Except as set forth below, a non-U.S. holder generally will not be subject to U.S. federal income or withholding tax in respect of any gain on a sale, exchange or other taxable disposition of our shares unless:

We have not determined whether we are a U.S. real property holding corporation, and no assurance can be given that we are not or will not become one in the future. If, however, we are or become a U.S. real property holding corporation, so long as our shares are regularly traded on an established securities market, generally only a non-U.S. holder who holds or held directly or indirectly (at any time during the shorter of the five year period ending on the date of disposition or the non-U.S. holder’s holding period) more than five percent of our shares will be subject to United States federal income tax on the disposition of our shares. Non-U.S. holders should consult their own advisors about the consequences that could result if we are, or become, a U.S. real property holding corporation.

Information Reporting and Backup Withholding Requirements

We must annually report to the IRS and to each non-U.S. holder any dividend income that is subject to U.S. federal withholding tax, or that is exempt from such withholding tax pursuant to an income tax treaty. Copies of these information returns also may be made available under the provisions of a specific treaty or agreement to the tax authorities of the country in which the non-U.S. holder resides. Under certain circumstances, the Code imposes a backup withholding obligation (at a rate of 28%) on certain reportable payments. Dividends paid to a non-U.S. holder of our shares generally will be exempt from backup withholding if the non-U.S. holder provides a properly executed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or otherwise establishes an exemption.

The payment of the proceeds from the disposition of our shares to or through the U.S. office of any broker, U.S. or foreign, will be subject to information reporting and possible backup withholding unless the owner certifies as to its non-U.S. status under penalties of perjury or otherwise establishes an exemption, provided that the broker does not have actual knowledge or reason to know that the holder is a U.S. person or that the conditions of any other exemption are not, in fact, satisfied. The payment of the proceeds from the disposition of our shares to or through a non-U.S. office of a non-U.S. broker will not be subject to information reporting or backup withholding unless the non-U.S. broker has certain types of relationships with the United States, or a U.S. related person. In the case of the payment of the proceeds from the disposition of our shares to or through a non-U.S. office of a broker that is either a U.S. person or a U.S. related person, the Regulations require information reporting (but not backup withholding) on the payment unless the broker has documentary evidence in its files that the owner is a non-U.S. holder and the broker has no knowledge to the contrary. Non-U.S. holders should consult their own tax advisors on the application of information reporting and backup withholding to them in their particular circumstances (including upon their disposition of our shares).

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder will be refunded by the IRS or credited against the non-U.S. holder’s U.S. federal income tax liability, if any, provided that the required information is furnished to the IRS.

Non-U.S. holders are advised to consult their own tax advisers with respect to the particular tax consequences to them of an investment in us.

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Federal Estate Tax

Our shares beneficially owned by an individual who is not a citizen or resident of the U.S. (as defined for U.S. federal estate tax purposes) at the time of death will generally be includable in the decedent’s gross estate for U.S. federal estate tax purposes, unless an applicable estate tax treaty provides otherwise.

FATCA Withholding

Pursuant to Sections 1471 to 1474 of the Code and the Regulations promulgated thereunder (the provisions commonly known as FATCA), dividends paid and, after December 31, 2016, the gross proceeds of sale or other disposition of our shares, to a foreign financial institution may be subject to withholding at a rate of 30% unless (x)(1) such institution enters into an agreement with the U.S. government to withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners) or (2) such institution resides in a jurisdiction with which the United States has entered into an intergovernmental agreement to implement FATCA and (y) such foreign financial institution provides the withholding agent with a certification that it is eligible to receive payment free of FATCA withholding. The legislation also generally imposes a U.S. federal withholding tax of 30% on dividends paid and will impose a withholding tax at such rate on the gross proceeds from a sale or other disposition of our shares after December 31, 2016, to a non-financial foreign entity unless such entity provides the withholding agent with a certification (i) that such entity does not have any “substantial United States owners” or (ii) provides certain information regarding the entity’s “substantial United States owners,” which will in turn be provided to the U.S. tax authorities. A foreign financial institution or non-financial foreign entity can meet the certification requirements by providing a properly executed IRS Form W-8BEN, IRS Form W-8BEN-E or IRS Form W-8ECI, as applicable. Under certain circumstances, a U.S. holder or non-U.S. holder might be eligible for refunds or credits of such taxes from the IRS. Prospective investors are encouraged to consult with their own tax advisors regarding the possible implications of this legislation on their investment in our shares.

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UNDERWRITING

Barclays Capital Inc. is acting as representative of each of the underwriters named below. Under the terms of an underwriting agreement, which we will file as an exhibit to a current report on Form 8-K and incorporate by reference in this prospectus supplement and the accompanying prospectus, each of the underwriters named below has severally agreed to purchase from us the respective number of shares shown opposite its name below:

Underwriters		Number of Shares
Barclays Capital Inc.			1,460,938
Macquarie Capital (USA) Inc.			783,594
J.P. Morgan Securities LLC			757,032
RBC Capital Markets, LLC			531,250
SunTrust Robinson Humphrey, Inc.			531,250
Oppenheimer & Co. Inc.			265,625
Wells Fargo Securities, LLC			265,625
Merrill Lynch, Pierce, Fenner & Smith          Incorporated			119,531
BBVA Securities Inc.			119,531
BB&T Capital Markets, a division of BB&T Securities, LLC			119,531
Credit Agricole Securities (USA) Inc.			119,531
JonesTrading Institutional Services LLC			119,531
Regions Securities LLC			119,531
Total			5,312,500

The underwriting agreement provides that the underwriters’ obligation to purchase shares depends on the satisfaction of the conditions contained in the underwriting agreement including:

The underwriting agreement also provides that if an underwriter defaults, the purchase commitments of non-defaulting underwriters may also be increased or the offering may be terminated.

At our request, the underwriters have reserved approximately 4,000 shares to be offered in this offering for sale at the public offering price to each of James Hooke, our Chief Executive Officer, and Martin Stanley, our Chairman. The number of shares available for sale to the general public will be reduced by the number of such shares. Any such shares not so purchased will be offered by the underwriters to the general public on the same basis as all other shares offered.

Commissions and Expenses

The following table summarizes the underwriting discounts and commissions we will pay to the underwriters. These amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares. The underwriting fee is the difference between the initial price to the public and the amount the underwriters pay to us for the shares.

		No exercise				Full exercise
Per share		$	2.60			$	2.60
Total		$	13,812,500			$	15,884,375

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The underwriters have advised us that they propose to offer the shares directly to the public at the public offering price on the cover of this prospectus supplement and to selected dealers, which may include the underwriters, at such offering price less a selling concession not in excess of $1.560 per share. After the offering, the underwriters may change the offering price and other selling terms. Sales of shares made outside of the United States may be made by affiliates of the underwriters. Sales of shares made outside the United States may be made by affiliates of the underwriters.

The expenses of the offering that are payable by us are estimated to be $450,000 (excluding underwriting discounts and commissions).

Option to Purchase Additional Shares

We have granted the underwriters an option exercisable for 30 days after the date of the underwriting agreement, to purchase, from time to time, in whole or in part, up to an aggregate of 796,875 shares at the public offering price less underwriting discounts and commissions and any dividends or distributions paid by us on the 5,312,500 shares offered hereby but not on the shares sold by us pursuant to the underwriters’ option to purchase additional shares. To the extent that this option is exercised, each underwriter will be obligated, subject to certain conditions, to purchase its pro rata portion of these additional shares based on the underwriter’s percentage underwriting commitment in the offering as indicated in the table at the beginning of this Underwriting Section.

Lock-Up Agreements

We, all of our directors and executive officers and our Manager have agreed that, subject to certain exceptions, without the prior written consent of Barclays Capital Inc., we and they will not directly or indirectly (1) offer for sale, sell, pledge, or otherwise dispose of (or enter into any transaction or device that is designed to, or could reasonably be expected to, result in the disposition by any person in privity with such persons of) any shares (including, without limitation, shares that may be issued upon exercise of any options or warrants) or securities convertible into or exercisable or exchangeable for shares, (2) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic consequences of ownership of the shares, (3) make any demand for or exercise any right or file or cause to be filed a registration statement, including any amendments thereto, with respect to the registration of any shares or securities convertible, exercisable or exchangeable into shares or any of our other securities, or (4) publicly disclose the intention to do any of the foregoing for a period of 45 days after the date of this prospectus supplement. The foregoing does not apply to shares to be sold by us pursuant to the underwriting agreement and certain other exceptions, including the issuance of shares by us to our Manager in connection with the reinvestment by our Manager of fees payable by us to our Manager under the management services agreement and the sale or disposition by our Manager of shares issued by us to our Manager in connection with the reinvestment of such fees.

Barclays Capital Inc., in its sole discretion, may release the shares and other securities subject to the lock-up agreements described above in whole or in part at any time with or without notice. When determining whether or not to release the shares and other securities from lock-up agreements, Barclays Capital Inc. will consider, among other factors, the holder’s reasons for requesting the release, the number of shares and other securities for which the release is being requested and market conditions at the time.

Indemnification

We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act, and to contribute to payments that the underwriters may be required to make for these liabilities.

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Stabilization, Short Positions and Penalty Bids

The representative may engage in stabilizing transactions, short sales and purchases to cover positions created by short sales, and penalty bids or purchases for the purpose of pegging, fixing or maintaining the price of the shares, in accordance with Regulation M under the Securities Exchange Act of 1934, as amended:

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our shares or preventing or retarding a decline in the market price of the shares. As a result, the price of the shares may be higher than the price that might otherwise exist in the open market. These transactions may be effected on the NYSE or otherwise and, if commenced, may be discontinued at any time.

Neither we nor any of the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the shares. In addition, neither we nor any of the underwriters make representation that the representative will engage in these stabilizing transactions or that any transaction, once commenced, will not be discontinued without notice.

Electronic Distribution

A prospectus in electronic format may be made available on the Internet sites or through other online services maintained by one or more of the underwriters and/or selling group members participating in this offering, or by their affiliates. In those cases, prospective investors may view offering terms online and, depending upon the particular underwriter or selling group member, prospective investors may be allowed to place orders online. The underwriters may agree with us to allocate a specific number of shares for sale to online brokerage account holders. Any such allocation for online distributions will be made by the representative on the same basis as other allocations.

Other than the prospectus in electronic format, the information on any underwriter’s or selling group member’s web site and any information contained in any other web site maintained by an underwriter or selling group member is not part of the prospectus or the registration statement of which this prospectus supplement and the accompanying prospectus forms a part, has not been approved and/or endorsed by us or any underwriter or selling group member in its capacity as underwriter or selling group member and should not be relied upon by investors.

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Stamp Taxes

If you purchase shares offered in this prospectus supplement and the accompanying prospectus, you may be required to pay stamp taxes and other charges under the laws and practices of the country of purchase, in addition to the offering price listed on the cover page of this prospectus supplement and the accompanying prospectus.

Settlement

We expect that delivery of the shares will be made against payment therefor on or about March 2, 2015 (this settlement cycle being referred to as “T+2”).

Relationships/FINRA Rules

Certain of the underwriters and their related entities have engaged, and may in the future engage, in commercial and investment banking transactions with us in the ordinary course of their business. They have received, and expect to receive, customary compensation and expense reimbursement for these commercial and investment banking transactions. For instance, Barclays Capital Inc. and Macquarie Capital (USA) Inc. are joint lead bookrunners of Atlantic Aviation’s existing credit facility and their affiliates are joint lead arrangers and lenders under such facility. IMTT and Hawaii Gas are also parties to various loan agreements and credit facilities under which affiliates of the underwriters serve as trustees, agents and lenders. In addition, Macquarie Capital (USA) Inc. acted as joint bookrunner and lead placement agent for a notes offering by Hawaii Gas. Barclays Capital Inc. is acting as financial advisor to the Company in connection with the acquisition of BEC and acted as financial advisor to the Company in connection with the IMTT Acquisition. Barclays Capital Inc. and Macquarie Capital (USA) Inc. acted as financial advisor to the Company in connection with our acquisition of Galaxy Aviation. Barclays Capital Inc., Macquarie Capital (USA) Inc., J.P. Morgan Securities LLC, RBC Capital Markets, LLC, SunTrust Robinson Humphrey, Inc., Oppenheimer & Co. Inc., Wells Fargo Securities, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated, BBVA Securities Inc., BB&T Capital Markets, a division of BB&T Securities, LLC and Regions Securities LLC acted as underwriters in connection with the equity offering and the convertible senior notes offering that financed the IMTT Acquisition. Affiliates of Barclays Capital Inc., Macquarie Capital (USA) Inc., J.P. Morgan Securities LLC, SunTrust Robinson Humphrey, Inc. and RBC Capital Markets, LLC are lenders under our senior secured revolving credit facility. Macquarie Capital (USA) Inc. is an affiliate of our Manager.

Selling Restrictions

Other than in the United States, no action has been taken by us or the underwriters that would permit a public offering of the securities offered by this prospectus in any jurisdiction where action for that purpose is required. The securities offered by this prospectus may not be offered or sold, directly or indirectly, nor may this prospectus or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons into whose possession this prospectus comes are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus. This prospectus does not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus in any jurisdiction in which such an offer or a solicitation is unlawful.

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United Kingdom

Each underwriter has represented and agreed that:

Australia

No prospectus or other disclosure document (as defined in the Corporations Act 2001 (Cth) of Australia (“Corporations Act”)) in relation to the shares has been or will be lodged with the Australian Securities & Investments Commission (“ASIC”). This document has not been lodged with ASIC and is only directed to certain categories of exempt persons. Accordingly, if you receive this document in Australia:

Hong Kong

The contents of this prospectus supplement have not been reviewed by any regulatory authority in Hong Kong. You are advised to exercise caution in relation to the offer. If you are in any doubt about any of the contents of this prospectus supplement, you should obtain independent professional advice. Please note that (i) our shares may not be offered or sold in Hong Kong, by means of this prospectus supplement or any document other than to “professional investors” within the meaning of Part I of Schedule 1 of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) (SFO) and any rules made thereunder, or in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies Ordinance (Cap. 32, Laws of Hong Kong) (CO) or which do not constitute an offer or invitation to the public for the purpose of the CO or the SFO, and (ii) no advertisement, invitation or document relating to our shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere) which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to the shares which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the SFO and any rules made thereunder.

Japan

Our shares have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (the Financial Instruments and Exchange Law) and our shares will not be offered or sold, directly or indirectly, in Japan, or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to

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others for re-offering or resale, directly or indirectly, in Japan, or to a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Law and any other applicable laws, regulations and ministerial guidelines of Japan.

Singapore

This document has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this document and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of our shares may not be circulated or distributed, nor may our shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (the “SFA”), (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions specified in Section 275, of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where our shares are subscribed or purchased under Section 275 by a relevant person which is:

(4) as specified in Section 276(7) of the SFA.

Dubai International Financial Centre

This prospectus supplement relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority (“DFSA”). This prospectus supplement is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement nor taken steps to verify the information set forth herein and has no responsibility for the prospectus supplement. The shares to which this prospectus supplement relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the shares offered should conduct their own due diligence on the shares. If you do not understand the contents of this prospectus supplement you should consult an authorized financial advisor.

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LEGAL MATTERS

The validity of the securities offered hereby will be passed upon for us by White & Case LLP, New York, New York. Weil Gotshal & Manges LLP, New York, New York, is advising the underwriters in connection with the offering of the shares.

EXPERTS

The consolidated financial statements of Macquarie Infrastructure Company LLC and subsidiaries as of December 31, 2014 and 2013 and for each of the years in the three year period ended December 31, 2014, and management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2014 have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent auditors, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The audit report on the effectiveness of internal control over financial reporting as of December 31, 2014 contains an explanatory paragraph that states that Macquarie Infrastructure Company LLC acquired IMTT Holdings Inc. during 2014, and management excluded from its assessment of the effectiveness of Macquarie Infrastructure Company LLC’s internal control over financial reporting as of December 31, 2014, IMTT Holdings Inc.’s internal control over financial reporting associated with total assets of $4.1 billion and total revenues of $255.9 million included in the consolidated financial statements of Macquarie Infrastructure Company LLC as of and for the year ended December 31, 2014. Our audit of internal control over financial reporting of Macquarie Infrastructure Company LLC also excluded an evaluation of the internal control over financial reporting of IMTT Holdings Inc.

The consolidated financial statements of IMTT Holdings Inc. and subsidiaries as of December 31, 2013 and 2012, and for each of the years then ended, have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent auditors, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We are required to comply with the reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and, in accordance with those requirements, we file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC’s toll-free number at 1-800-SEC-0330 for further information about the Public Reference Room. Our SEC filings are also available to the public from the SEC’s website at www.sec.gov and can be found by searching the EDGAR archives on the website. In addition, our SEC filings and other information about us may also be obtained from our website at www.macquarie.com/mic, although information on our website is not incorporated by reference into and does not constitute a part of this prospectus supplement. Our shares are listed on the NYSE under the symbol “MIC” and all reports, proxy statements and other information filed by us with the NYSE may be inspected at the NYSE’s offices at 20 Broad Street, New York, New York 10005.

We have filed a registration statement on Form S-3 to register with the SEC the securities covered by this prospectus supplement. This prospectus supplement is a part of the registration statement and does not contain all the information in the registration statement. Whenever a reference is made in this prospectus supplement to a contract or other document, the reference is only a summary and you should refer to the exhibits that are a part of the registration statement or our other SEC filings for a copy of the contract or other document.

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INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” the information we file with them, which means that we can disclose important information to you by referring you to those documents that are considered part of this prospectus supplement. Later information that we file will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than portions of these documents that are deemed to have been furnished and not filed in accordance with SEC rules) until the offering of the particular securities covered by this prospectus supplement has been completed. This prospectus supplement is part of a registration statement filed with the SEC.

We are incorporating by reference into this prospectus supplement the following documents filed with the SEC (excluding any portions of such documents that have been “furnished” but not “filed” for purposes of the Exchange Act):

The documents incorporated by reference into this prospectus supplement are available from us upon request. We will provide a copy of any and all of the information that is incorporated by reference into this prospectus supplement to any person, without charge, upon written or oral request. Requests for such copies should be directed to the following:

Macquarie Infrastructure Company LLC
125 West 55^th Street
New York, New York 10019
Attention: Investor Relations
Telephone: (212) 231-1000

Except as provided above, no other information, including, but not limited to, information on our website, is incorporated by reference into this prospectus supplement or as a part of this prospectus supplement.

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PROSPECTUS

Shares

Debt Securities

Macquarie Infrastructure Company LLC

Macquarie Infrastructure Company LLC may sell, from time to time, limited liability company interests, which we refer to as shares, and debt securities, which we refer to, together with the shares, as securities. Macquarie Infrastructure Management (USA) Inc., our manager, as a selling security holder (our “Manager” or the “Selling Security Holder”), may sell, from time to time, shares in Macquarie Infrastructure Company LLC. We or the Selling Security Holder may offer for sale the securities covered by this prospectus, as applicable, directly to purchasers or through underwriters, broker-dealers or agents, in public or private transactions, at prevailing market prices or at privately negotiated prices, including in satisfaction of certain contractual obligations. For additional information on the methods of sale, you should refer to the section of this prospectus entitled “Plan of Distribution.” We and the Selling Security Holder may offer these securities, as applicable, at prices and on terms determined at the time of offering.

The shares covered by this prospectus are listed for trading on The New York Stock Exchange under the symbol “MIC.”

We will provide more specific information about the terms of an offering of these securities in supplements to this prospectus. This prospectus may not be used to offer or sell securities unless accompanied by a prospectus supplement. You should read this prospectus and any applicable prospectus supplements carefully before you invest. If any underwriters, broker-dealers or agents are involved in any offering, the names of such underwriters, broker-dealers or agents and any applicable commissions or discounts or other compensation will be described in the applicable prospectus supplement relating to the offering.

Investing in the securities involves risks that are described in the “Risk Factors” section beginning on page 3 of this prospectus. Risks may also be described in an accompanying prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is April 8, 2013.

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		Page
ABOUT THIS PROSPECTUS			ii
PROSPECTUS SUPPLEMENT			ii
FORWARD-LOOKING STATEMENTS			ii
WHERE YOU CAN FIND MORE INFORMATION			iv
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE			iv
MACQUARIE INFRASTRUCTURE COMPANY LLC			1
RISK FACTORS			3
USE OF PROCEEDS			8
RATIO OF EARNINGS TO FIXED CHARGES			9
DESCRIPTION OF OUR SHARES			10
DESCRIPTION OF DEBT SECURITIES			16
MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS			25
SELLING SECURITY HOLDER			30
PLAN OF DISTRIBUTION			31
LEGAL MATTERS			33
EXPERTS			33

Macquarie Infrastructure Company LLC is not an authorized deposit-taking institution for the purposes of the Banking Act 1959 (Commonwealth of Australia) and its obligations do not represent deposits or other liabilities of Macquarie Bank Limited ABN 46 008 583 542 (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of Macquarie Infrastructure Company LLC.

You should rely only on the information contained in this prospectus and any applicable prospectus supplement. We have not authorized anyone to provide you with information different from that contained in this prospectus and any applicable prospectus supplement. This prospectus and any applicable prospectus supplement may be used only for the purpose for which it has been published, and no person has been authorized to give any information not contained in this prospectus and any applicable prospectus supplement. If you receive any other information, you should not rely on it. We are not making an offer of these securities in any jurisdiction where the offer is not permitted.

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or SEC, using a “shelf” registration process. Under this shelf process, we may or the Selling Security Holder may sell securities covered by this prospectus in one or more offerings. Because we are a well-known seasoned issuer, as defined in Rule 405 of the Securities Act of 1933, as amended, or the Securities Act, we or the Selling Security Holder may, from time to time, add and offer additional securities by filing a prospectus supplement with the SEC at the time of the offer.

PROSPECTUS SUPPLEMENT

This prospectus provides you with a general description of the securities that we may offer. Each time that we offer securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add to, update or change information contained in this prospectus. Any statement that we make in this prospectus shall be modified or superseded by any inconsistent statement made by us in a prospectus supplement. You should read both this prospectus and any accompanying prospectus supplement, especially the section titled “Risk Factors,” together with the additional information described under the heading “Incorporation of Certain Documents by Reference” or incorporated by reference in this prospectus and any applicable prospectus supplement.

The prospectus supplement to be attached to the front of this prospectus will describe: the applicable public offering price, the price paid for the securities, the net proceeds, the manner of distribution and any underwriting compensation and the other specific material terms related to the offering of securities covered by this prospectus.

For more detail on the terms of the securities offered, see “Description of our Shares” and “Description of Debt Securities.”

FORWARD-LOOKING STATEMENTS

We have included or incorporated by reference into this prospectus, and from time to time may make in our public filings, press releases or other public statements, certain statements that may constitute forward-looking statements. These include without limitation those under the headings “Macquarie Infrastructure Company” and “Risk Factors,” as well as those contained in any prospectus supplement or in any document incorporated by reference into this prospectus or any applicable prospectus supplement. In addition, our management may make forward-looking statements to analysts, investors, representatives of the media and others. These forward-looking statements are not historical facts and represent only our beliefs regarding future events, many of which, by their nature, are inherently uncertain and beyond our control. We may, in some cases, use words such as “project,” “believe,” “anticipate,” “plan,” “expect,” “estimate,” “intend,” “should,” “would,” “could,” “potentially,” “may” or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements.

In connection with the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, we are identifying important factors that, individually or in the aggregate, could cause actual results to differ materially from those contained in any forward-looking statements made by us. Any such forward-looking statements are qualified by reference to the following cautionary statements.

Forward-looking statements in this prospectus and any prospectus supplement (including any documents incorporated by reference herein or therein) are subject to a number of risks and uncertainties, some of which are beyond our control, including, among other things:

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Our actual results, performance, prospects or opportunities could differ materially from those expressed in or implied by the forward-looking statements. A description of risks that could cause our actual results to differ appears under the caption “Risk Factors” and elsewhere in this prospectus and any accompanying

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prospectus supplement and in the documents incorporated by reference into this prospectus and any accompanying prospectus supplement. It is not possible to predict or identify all risk factors and you should not consider that description to be a complete discussion of all potential risks or uncertainties that could cause our actual results to differ.

In light of these risks, uncertainties and assumptions, you should not place undue reliance on any forward-looking statements. The forward-looking events discussed in this prospectus or any accompanying prospectus supplement (including any documents incorporated by reference herein or therein) may not occur. These forward-looking statements are made as of the date of this prospectus. We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law. You should, however, consult further disclosures we may make in future filings with the SEC.

WHERE YOU CAN FIND MORE INFORMATION

We are required to comply with the reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and, in accordance with those requirements, we file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC’s toll-free number at 1-800-SEC-0330 for further information about the Public Reference Room. Our SEC filings are also available to the public from the SEC’s website at www.sec.gov and can be found by searching the EDGAR archives on the website. In addition, our SEC filings and other information about us may also be obtained from our website at www.macquarie.com/mic, although information on our website does not constitute a part of this prospectus. Our shares are listed on the New York Stock Exchange, or NYSE, under the symbol “MIC” and all reports, proxy statements and other information filed by us with the NYSE may be inspected at the NYSE’s offices at 20 Broad Street, New York, New York 10005.

We have filed a registration statement on Form S-3 to register with the SEC the securities covered by this prospectus. This prospectus is a part of the registration statement and does not contain all the information in the registration statement. Whenever a reference is made in this prospectus to a contract or other document, the reference is only a summary and you should refer to the exhibits that are a part of the registration statement or our other SEC filings for a copy of the contract or other document.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” the information we file with them, which means that we can disclose important information to you by referring you to those documents that are considered part of this prospectus. Later information that we file will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act until the offering of the particular securities covered by a prospectus supplement has been completed. This prospectus is part of a registration statement filed with the SEC.

We are incorporating by reference into this prospectus the following documents filed with the SEC (excluding any portions of such documents that have been “furnished” but not “filed” for purposes of the Exchange Act):

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The documents incorporated by reference in this prospectus are available from us upon request. We will provide a copy of any and all of the information that is incorporated by reference in this prospectus to any person, without charge, upon written or oral request. Requests for such copies should be directed to the following:

Macquarie Infrastructure Company LLC
125 West 55^th Street
New York, NY 10019
Attention: Investor Relations
Telephone: (212)-231-1825

Except as provided above, no other information, including, but not limited to, information on our website, is incorporated by reference into this prospectus or a part of this prospectus.

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MACQUARIE INFRASTRUCTURE COMPANY LLC

Macquarie Infrastructure Company, LLC, a Delaware limited liability company, was formed on April 13, 2004. Except as otherwise specified, “Macquarie Infrastructure Company”, “MIC,” “the Company”, “we,” “us,” and “our” refer to Macquarie Infrastructure Company LLC and its subsidiaries together from June 25, 2007 and, prior to that date, to Macquarie Infrastructure Company Trust, the Company and its subsidiaries. Macquarie Infrastructure Management (USA) Inc., which we refer to as our Manager, is part of the Macquarie Group, comprised of Macquarie Group Limited and its subsidiaries and affiliates worldwide.

General

We own, operate and invest in a diversified group of infrastructure businesses that provide basic services, such as chilled water for building cooling and gas utility services to businesses and individuals primarily in the U.S. The businesses we own and operate include:

Our businesses generally operate in sectors with significant barriers to entry, including high initial development and construction costs, the existence of long-term contracts or the requirement to obtain government approvals and a lack of immediate cost-efficient alternatives to the services provided. Overall they tend to generate sustainable long-term cash flows. Each of our operating businesses has its own management team and staff, as necessary, to conduct and support its operations.

We have elected to treat MIC as a corporation for federal tax purposes. As a result, all investor tax reporting regarding dividends will be provided on Form 1099.

Our Manager

MIC is managed externally by Macquarie Infrastructure Management (USA) Inc., our Manager. Our Manager is a member of the Macquarie Group, a diversified international provider of financial, advisory and investment services. The Macquarie Group is headquartered in Sydney, Australia and is a global leader in management of infrastructure investment vehicles on behalf of third-party investors and advising on the acquisition, disposition and financing of infrastructure assets.

We have entered into a management services agreement with our Manager. Our Manager is responsible for our day-to-day operations and affairs and oversees the management teams of our operating businesses. At the holding company level, the Company does not have any employees. Our Manager has assigned, or seconded, to the Company two of its employees to serve as chief executive officer and chief financial officer of the Company and seconds or makes other personnel available as required. The services performed for the Company by our Manager are provided at our Manager’s expense, and include the compensation of our seconded personnel.

We pay our Manager a quarterly base management fee based primarily on our market capitalization. Our Manager can also earn a performance fee if the quarterly total return to shareholders (capital appreciation plus

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dividends) exceeds the quarterly total return based on a weighted average of two benchmark utilities indices. For our Manager to be eligible for the performance fee, MIC’s quarterly total returns must be positive and in excess of any prior underperformance. The performance fee is equal to 20% of the difference between the benchmark return and the return for our shareholders. Our Manager may, in its sole discretion, choose to retain base and/or performance fees in cash or to reinvest such fees in additional shares.

We believe that Macquarie Group’s demonstrated expertise and experience in the management, acquisition and funding of infrastructure businesses provide us with an advantage in pursuing our strategy. Our Manager is part of the Macquarie Funds Group, the asset management division of Macquarie globally. Macquarie-managed entities own, operate and/or invest in a global portfolio of approximately 110 businesses including toll roads, airports and airport-related infrastructure, bulk liquid storage, ports, communications, media, electricity and gas distribution networks, water utilities, renewable energy generation, aged care, rail and ferry assets across 25 countries.

Principal Executive Offices

Our principal executive offices are located at 125 West 55^th Street, New York, NY 10019. Our telephone number at that location is (212) 231-1000. You may also obtain additional information about us from our website, www.macquarie.com/mic. Information on our website is not incorporated by reference into this prospectus or a part of this prospectus.

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RISK FACTORS

An investment in our shares involves a number of risks. For a discussion of risks related to our business, please see Part I, Item 1A “Risk Factors” of our Annual Report on Form 10-K for the year ended December 31, 2012, filed with the SEC on February 20, 2013, which is incorporated in this prospectus by reference. You should carefully read and consider the risks described below and elsewhere in this prospectus, as well as those described in the documents we incorporate by reference, before investing in our securities.

Risks Related to Ownership of Our Shares

MIC’s inherently complex structure and financial reporting may make it difficult for some investors to value our shares.

We are a limited liability company structured as a non-operating holding company of four operating businesses and one substantial, unconsolidated investment. We have elected to be treated as a corporation for tax purposes. Our consolidated federal income tax group is comprised of two of our operating businesses. Our investment and one of our operating businesses file stand-alone federal income tax returns. To the extent we receive distributions either from our investment or operating business that is not a part of our tax group, and these distributions are characterized as a dividend for tax purposes (as opposed to a return of capital), such distributions would be eligible for the federal dividends received deductions (80% exclusion in calculating taxes). These and other factors may make it difficult for some potential investors, particularly those without a moderate level of financial acumen, to accurately assess the value of our shares and may adversely impact the market for our shares.

Our Manager’s decision to reinvest its quarterly base management fees and performance fees, as applicable, in our shares or retain the cash will affect holders of our shares differently.

Our Manager earned $7.1 million and $22.0 million in base management and performance fees, respectively, during the first quarter of 2013 and $21.9 million and $67.3 million in base management and performance fees, respectively, during 2012. These fees are based on the Company’s market capitalization and performance and maybe higher or lower than these levels in the future. Our Manager, in its sole discretion, may elect to retain base management fees and performance fees, if applicable, paid in cash or to reinvest such payments in additional shares. In the event the Manager chooses not to reinvest the fees to which it is entitled in additional shares, the amount paid will reduce the cash that may otherwise be distributed as a dividend to all shareholders or used in the Company’s operations. In the event the Manager chooses to reinvest the fees to which it is entitled in additional shares, effectively returning the cash to us, such reinvestment will dilute existing shareholders by the increase in the percentage of shares owned by the Manager. Either option may adversely impact the market for our shares.

Our reported EBITDA excluding non-cash items and free cash flow will be lower if the Manager elects to retain base management and/or performance fees in cash as compared with its election to reinvest such base management and/or performance fees in additional shares. The amount by which these items are lower could be material. See Part II, Item 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Results of Operations” of our Annual Report on Form 10-K for the year ended December 31, 2012, filed with the SEC on February 20, 2013 for further information on how we calculate these items and what management uses these items for.

Our Manager owns a significant portion of MIC’s shares outstanding. A sale of all or a portion of the interests owned by our Manager could be interpreted by the equity markets as a lack of confidence in the prospects of the Company.

Our Manager, in its sole discretion, determines whether to reinvest base and performance fees in shares and whether to hold or sell those securities. Reinvestment of base and performance fees in additional shares during the past two years has substantially increased our Manager’s ownership stake in the Company. As of February 20, 2013, our Manager owned 11.55% of our outstanding shares. If our Manager decides, for reasons other than the performance and prospects of the Company, to reduce its position in the Company, such sales

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may be interpreted by some market participants as a lack of confidence in the Company and put downward pressure on the market price of our shares.

Our total assets include a substantial amount of goodwill and intangible assets. The write-off of a significant portion of intangible assets would negatively affect our reported earnings.

Our total assets reflect a substantial amount of goodwill and other intangible assets. At December 31, 2012, goodwill and other intangible assets, net, represented approximately 51.3% of total assets from continuing operations. Goodwill and other intangible assets were primarily recognized as a result of the acquisitions of our businesses and investments. Other intangible assets consist primarily of airport operating rights, customer relationships and trade names. On at least an annual basis, we assess whether there has been an impairment in the value of goodwill and assess for impairment of other intangible assets with indefinite lives when there are triggering events or circumstances. If the carrying value of the tested asset exceeds its estimated fair value, impairment is deemed to have occurred. In this event, the amount is written down to fair value. Under current accounting rules, this would result in a charge to reported earnings. We have recognized significant impairments in the past, and any future determination requiring the write-off of a significant portion of goodwill or other intangible assets would negatively affect our reported earnings and total capitalization, and could be material.

Our total assets include a substantial amount of goodwill, intangible assets and fixed assets. The depreciation and amortization of these assets may negatively impact our reported earnings.

The high level of intangible and physical assets written up to fair value upon acquisition of our businesses generates substantial amounts of depreciation and amortization. These non-cash items serve to lower net income as reported in our statement of operations as well as our taxable income. The generation of net losses or relatively small net income may contribute to a net operating loss (NOL) carryforward that can be used to offset currently taxable income in future periods. However, the continued reporting of little or negative net income may adversely affect the attractiveness of the Company among some potential investors and may reduce the market for our shares.

Our Manager’s affiliation with Macquarie Group Limited and the Macquarie Group may result in conflicts of interest or a decline in our stock price.

Our Manager is an affiliate of Macquarie Group Limited and a member of the Macquarie Group. From time to time, we have entered into, and in the future we may enter into, transactions and relationships involving Macquarie Group Limited, its affiliates, or other members of the Macquarie Group. Such transactions have included and may include, among other things, the entry into debt facilities and derivative instruments with members of the Macquarie Group serving as lender or counterparty, and financial advisory services provided to us by the Macquarie Group.

Although our audit committee, all of the members of which are independent directors, is required to approve of any related party transactions, including those involving members of the Macquarie Group or its affiliates, the relationship of our Manager to the Macquarie Group may result in conflicts of interest.

In addition, as a result of our Manager’s being a member of the Macquarie Group, negative market perceptions of Macquarie Group Limited generally or of Macquarie’s infrastructure management model, or Macquarie Group statements or actions with respect to other managed vehicles, may affect market perceptions of our Company and cause a decline in the price of our shares unrelated to our financial performance and prospects.

Our Manager can resign with 90 days notice and we may not be able to find a suitable replacement within that time, resulting in a disruption in our operations, which could adversely affect our financial results and negatively impact the market price of our shares.

Our Manager has the right, under the management services agreement, to resign at any time with 90 days notice, whether we have found a replacement or not. The resignation of our Manager will trigger mandatory repayment obligations under debt facilities at our operating companies other than IMTT and Hawaii Gas. If our Manager resigns, we may not be able to find a new external manager or hire internal management with similar expertise within 90 days to provide the same or equivalent services on acceptable terms, or at all. If

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we are unable to do so quickly, our operations are likely to experience a disruption, our financial results could be adversely affected, perhaps materially, and the market price of our shares may decline substantially. In addition, the coordination of our internal management, acquisition activities and supervision of our businesses and investments are likely to suffer if we were unable to identify and reach an agreement with a single institution or group of executives having the expertise possessed by our Manager and its affiliates. Furthermore, if our Manager resigns, the Company and its subsidiaries will be required to cease use of the Macquarie brand entirely, and change their names to remove any reference to “Macquarie.” This may cause the value of the Company and the market price of our shares to decline.

In the event of the underperformance of our Manager, we may be unable to remove our Manager, which could limit our ability to improve our performance and could adversely affect the market price of our shares.

Under the terms of the management services agreement, our Manager must significantly underperform in order for the management services agreement to be terminated. The Company’s Board of Directors cannot remove our Manager unless:

Because our Manager’s performance is measured by the market performance of our shares relative to the weighted average of two benchmark utilities indices, even if the absolute market performance of our shares does not meet expectations, the Company’s Board of Directors cannot remove our Manager unless the market performance of our shares also significantly underperforms the weighted average of such benchmark utilities indices. If we were unable to remove our Manager in circumstances where the absolute market performance of our shares does not meet expectations, the market price of our shares could be negatively affected.

Certain provisions of the management services agreement and the operating agreement of the Company makes it difficult for third parties to acquire control of the Company and could deprive investors of the opportunity to obtain a takeover premium for their shares.

In addition to the limited circumstances in which our Manager can be terminated under the terms of the management services agreement, the management services agreement provides that in circumstances where the stock ceases to be listed on a recognized U.S. exchange as a result of the acquisition of stock by third parties in an amount that results in the stock ceasing to meet the distribution and trading criteria on such exchange or market, the Manager has the option to either propose an alternate fee structure and remain our Manager or resign, terminate the management services agreement upon 30 days’ written notice and be paid a substantial termination fee. The termination fee payable on the Manager’s exercise of its right to resign as our Manager subsequent to a delisting of our shares could delay or prevent a change in control that may favor our shareholders. Furthermore, in the event of such a delisting, any proceeds from the sale, lease or exchange of a significant amount of assets must be reinvested in new assets of our Company, subject to debt repayment obligations. We would also be prohibited from incurring any new indebtedness or engaging in any transactions with shareholders of the Company or its affiliates without the prior written approval of the Manager. These provisions could deprive shareholders of opportunities to realize a premium on the shares owned by them.

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The operating agreement of the Company, which we refer to as the LLC agreement, contains a number of provisions that could have the effect of making it more difficult for a third-party to acquire, or discouraging a third-party from acquiring, control of the Company. These provisions include:

The market price and marketability of our shares may from time to time be significantly affected by numerous factors beyond our control, which may adversely affect our ability to raise capital through future equity financings.

The market price of our shares may fluctuate significantly. Many factors that are beyond our control may significantly affect the market price and marketability of our shares and may adversely affect our ability to raise capital through equity financings. These factors include the following:

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Risks Related to Taxation

We have significant income tax Net Operating Losses, or NOLs, which may not be realized before they expire.

We have $192.2 million in federal NOL carryforwards at December 31, 2012. While we have concluded that all but $7.8 million of the NOLs will more likely than not be realized, there can be no assurance that we will utilize the NOLs generated to date or any NOLs we might generate in the future. In addition, we have incurred state NOLs and have provided a valuation allowance against a portion of those. As with our federal NOLs, there is also no assurance that we will utilize those state losses or future losses that maybe generated. Further, the State of Illinois has suspended the use of NOL carryforwards through 2014, similar to the State of California’s suspension of an NOL deduction through 2011 for large corporations. There can be no assurance that other states will not suspend the use of NOL carryforwards or that California and Illinois will not extend the suspension of the use of NOL carryforwards.

Our ability to use our NOL carryforwards to offset future taxable income may be subject to certain limitations.

In general, under Section 382 of the Internal Revenue Code of 1986, as amended, or the Code, a corporation (or other entity taxable as a corporation, such as the Company) that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change NOLs and certain other tax attributes to offset future taxable income. Generally speaking, an “ownership change” occurs if the aggregate percentage ownership of the stock of the corporation held by one or more “five-percent shareholders” (as defined in the Code) increases by more than fifty percentage points over such shareholders’ lowest percentage ownership during the testing period, which is generally the three year-period ending on the transaction date. If we undergo an ownership change, our ability to utilize NOLs and certain other tax attributes could be limited.

The current treatment of qualified dividend income and long-term capital gains under current U.S. federal income tax law may be adversely affected, changed or repealed in the future.

Under current law, qualified dividend income and long-term capital gains are taxed to non-corporate investors at a maximum U.S. federal income tax rate of 20% beginning in 2013. This tax treatment may be adversely affected, changed or repealed by future changes in tax laws at any time. In addition, certain holders that are individuals, estates or trusts are subject to a 3.8% surtax on all or a portion of their “net investment income,” which may include all or a portion of their dividend income and net gains from the disposition of our shares. This may affect market perceptions of our Company and the market price of our shares could be negatively affected.

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USE OF PROCEEDS

Unless indicated otherwise in the applicable prospectus supplement, we expect to use the net proceeds from our sale of securities under this prospectus for general corporate purposes, including, but not limited to, repayment or refinancing of borrowings, working capital, capital expenditures, investments and the financing of possible acquisitions. Additional information on the use of net proceeds from the sale of securities offered by this prospectus may be set forth in the prospectus supplement relating to such offering.

We will not receive any proceeds from sales of shares offered by the Selling Security Holder under this prospectus.

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RATIO OF EARNINGS TO FIXED CHARGES

Set forth below is information concerning our ratio of earnings to fixed charges from continuing operations.

		Year Ended December 31,
		2012				2011				2010				2009				2008
Ratio of Earnings to Fixed Charges(1)			2.14				1.38				N/M	(2)			N/M	(2)			N/M	(2)

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DESCRIPTION OF OUR SHARES

General

The following is a summary of the material terms of the limited liability company interests in Macquarie Infrastructure Company LLC, which we refer to as shares. Our third amended and restated operating agreement, as amended from time to time, which we refer to as the LLC agreement, provides for the issuance of our shares and the distributions on and voting rights of our shares. The following description is subject to the provisions of the Delaware Limited Liability Company Act. Certain provisions of the LLC agreement are intended to be consistent with the Delaware General Corporation Law, and the powers of our company and the shareholders of our company are generally intended to be similar in many respects to those of a Delaware corporation. In some instances, this summary refers to specific differences between the rights of holders of our shares, on the one hand, and the rights of shareholders of a Delaware corporation, on the other hand. Similarly, in some instances this summary refers to specific differences between the attributes of our shares, on the one hand, and shares of stock of a Delaware corporation, on the other hand. The statements that follow are subject to and are qualified in their entirety by reference to all of the provisions of the LLC agreement, which will govern your rights as a holder of our shares, which is filed as an exhibit to our Current Report on Form 8-K, filed with the SEC on June 22, 2007.

Authorized Shares

We are authorized to issue 500,000,000 shares. As of February 20, 2013, we had 47,453,943 shares outstanding. We are authorized to issue a single class of shares. All of our shares will be fully paid and nonassessable upon payment therefor.

Dividends and Distributions

Our board of directors may, in its sole discretion and at any time, declare and pay dividends and make and pay distributions from our cash flow to the holders of our shares, in proportion to their percentage of the aggregate number of our outstanding shares, as they appear on the share register on the related record date. “Net cash flow,” for any period, is defined as our gross cash proceeds for such period less the portion thereof used to pay or establish reserves for our expenses, debt payments, capital improvements, replacements and contingencies, all as determined by our board of directors. Net cash flow will not be reduced by depreciation, amortization, cost recovery deductions or similar allowances, but will be increased by any reductions of reserves discussed in the prior sentence.

Agreement to be Bound by the LLC Agreement; Power of Attorney

By purchasing a share in us, you will be admitted as a member of our company and will be deemed to have agreed to be bound by the terms of the LLC agreement. Pursuant to this agreement, each shareholder and each person who acquires a share from a shareholder grants to our board of directors (and, if appointed, a liquidator) a power of attorney to, among other things, execute and file documents required for our qualification, continuance or dissolution. The power of attorney also grants our board of directors the authority to make certain amendments to, and to make consents and waivers under and in accordance with, the LLC agreement.

Limited Liability

The Delaware Limited Liability Company Act provides that any shareholder who receives a distribution and knew at the time of the distribution that the distribution was in violation of the Delaware Limited Liability Company Act shall be liable to us for the amount of the distribution for three years. Under the Delaware Limited Liability Company Act, a limited liability company may not make a distribution to any shareholder if, after the distribution, all liabilities of the company, other than liabilities to shareholders on account of their limited liability company interests and liabilities for which the recourse of creditors is limited to specific property of the company, would exceed the fair value of the assets of the company. For the purpose of determining the fair value of the assets of a company, the Delaware Limited Liability Company Act provides that the fair value of property subject to liability for which recourse of creditors is limited shall be included in the assets of the company only to the extent that the fair value of that property exceeds the nonrecourse liability. Under the Delaware Limited Liability Company Act, an assignee who becomes a

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substituted shareholder of a company is liable for the obligations of his assignor to make contributions to the company, except the assignee is not obligated for liabilities unknown to him at the time he became a shareholder and that could not be ascertained from the limited liability company agreement.

Voting Rights

Each outstanding share is entitled to one vote on any matter with respect to which our shareholders are entitled to vote, as provided in the LLC agreement and as detailed below.

The LLC agreement provides that the shareholders are entitled, at our annual meeting of shareholders, to vote for the election of all of the directors other than any director appointed by our Manager. Because the LLC agreement does not provide for cumulative voting rights, the holders of a plurality of the voting power of the then outstanding shares represented at a meeting will effectively be able to elect all our directors standing for election.

Right to Bring a Derivative Action and Enforcement of the Provisions of the LLC Agreement by Holders of our Shares

The LLC agreement provides that a holder of our shares has the right to directly institute a legal proceeding against us to enforce the provisions of the LLC agreement.

Optional Purchase by Acquirer of 90% of our Shares

The LLC agreement provides that, if at any time more than 90% of our then outstanding shares are held by one person, whom we refer to as the acquirer, such acquirer has the right to purchase from the other shareholders for cash all, but not less than all, of the outstanding shares that the acquirer does not own. The acquirer can exercise its right to effect such purchase by delivering notice to us of its election to make the purchase not less than 60 days prior to the date which it selects for the purchase. We will use reasonable efforts to cause the transfer agent to mail the notice of the purchase to the record holders of our shares at least 30 days prior to purchase.

Upon the acquirer’s exercise of its purchase right, the LLC agreement provides that members other than the acquirer shall be required to sell all, but not less than all, of their outstanding shares at the offer price. The offer price will be equal to the average closing price (as described below) per share, on the 20 trading days immediately prior to, but not including, the date of the acquisition exchange. While this provision of the LLC agreement provides for a fair price requirement, the LLC agreement does not provide members with appraisal rights that shareholders of a Delaware corporation would be entitled to under Section 262 of the Delaware General Corporation Law.

The closing price of our shares, as applicable, on any date of determination means:

Dissolution of our Company

The LLC agreement provides for the dissolution and winding up of our company upon the occurrence of:

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Following the occurrence of a dissolution event with respect to us, we will be wound up in accordance with the terms of the LLC agreement. Upon our winding up, the then holders of our shares will be entitled to share ratably in our assets legally available for distribution following payment to creditors.

Anti-Takeover Provisions

Certain provisions of the management services agreement and the LLC agreement may make it more difficult for third parties to acquire control of us by various means. These provisions could deprive our shareholders of opportunities to realize a premium on the shares owned by them. In addition, these provisions may adversely affect the prevailing market price of the shares. These provisions are intended to:

Anti-Takeover Effects of the Management Services Agreement

The limited circumstances in which our Manager may be terminated means that it will be very difficult for a potential acquirer to take over the management and operation of our business. Under the terms of the management services agreement, our Manager may only be terminated by us in the following circumstances:

In addition to the limited circumstances in which our Manager can be terminated under the terms of the management services agreement, the management services agreement provides that in circumstances where the shares cease to be listed on a recognized U.S. national securities exchange as a result of the acquisition of shares by third parties in an amount that results in the shares ceasing to meet the distribution and trading criteria on such exchange or market, our Manager has the option to either propose an alternate fee structure and remain our Manager or resign, terminate the management services agreement upon 30 days’ written notice and be paid a substantial termination fee. The termination fee payable on our Manager’s exercise of its right to resign as our Manager subsequent to a delisting of our shares could delay or prevent a change in control that may favor our shareholders. Furthermore, in the event of such a delisting and unless otherwise approved

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in writing by our Manager, any proceeds from the sale, lease or exchange of a significant amount of assets must be reinvested in new assets of our company. We will also be prohibited from incurring any new indebtedness or engaging in any transactions with our shareholders or their affiliates without the prior written approval of our Manager. These provisions could deprive our shareholders of opportunities to realize a premium on the shares owned by them.

Furthermore, upon resignation of our Manager and the termination of the management services agreement, or within 30 days of a delisting of our shares unless otherwise agreed by our Manager, we and our subsidiaries will cease using the Macquarie brand entirely, including changing our names to remove any reference to “Macquarie.” Similarly, if our Manager’s appointment is terminated by us, we and our subsidiaries will cease using the Macquarie brand within 30 days of termination.

Anti-Takeover Provisions in the LLC Agreement

A number of provisions of the LLC agreement also could have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from acquiring, control of us. The LLC agreement prohibits the merger or consolidation of us with or into any limited liability company, corporation, trust or any other unincorporated business or the sale, lease or exchange of all or substantially all of our assets unless the board of directors adopts a resolution by a majority vote approving such action and unless such action is approved by the affirmative vote of a majority of the outstanding shares entitled to vote thereon; provided, however, that any shares held by the Manager or an affiliate or associate of the Manager shall not be entitled to vote to approve any merger or consolidation with or into, or sale, lease or exchange to, the Manager or any affiliate or an associate thereof. In addition, the LLC agreement contains provisions based on Section 203 of the Delaware General Corporation Law which prohibit us from engaging in a business combination with an interested shareholder unless such business combination is approved by the affirmative vote of the holders of 66 2/3% of our outstanding shares (other than those shares held by the interested shareholder or any affiliate or associate thereof).

A “business combination” means:

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An “interested shareholder” is a person (other than our Manager, us or any subsidiary of ours or any employee benefit plan) who:

Subject to the right of our Manager to appoint one director and his or her successor in the event of a vacancy, the LLC agreement authorizes only our board of directors to fill vacancies, including for newly created directorships. This provision could prevent a shareholder of ours from effectively obtaining an indirect majority representation on our board of directors by permitting the existing board to increase the number of directors and to fill the vacancies with its own nominees. The LLC agreement also provides that, with the exception of the director appointed to serve as Chairman by our Manager, directors may be removed only for cause and only by the affirmative vote of holders of 66 2/3% of our outstanding shares.

The LLC agreement does not permit holders of our shares to act by written consent. Instead, shareholders may only take action via proxy, which may be presented at a duly called annual or special meeting of our shareholders. Furthermore, the LLC agreement provides that special meetings may only be called by the chairman of the board of directors of our company or by resolution adopted by our board of directors. The LLC agreement also provides that shareholders seeking to bring business before an annual meeting of members or to nominate candidates for election as directors at an annual meeting of shareholders of our company, must provide notice thereof in writing to us not less than 120 days and not more than 150 days prior to the anniversary date of our preceding year’s annual meeting. In addition, the shareholder furnishing such notice must be a shareholder of record on both (1) the date of delivering such notice and (2) the record date for the determination of shareholders entitled to vote at such meeting. The LLC agreement specifies certain requirements as to the form and content of a shareholder’s notice. These provisions may preclude shareholders from bringing matters before an annual meeting or from making nominations for directors at an annual or special meeting.

Authorized but unissued shares are available for future issuance, without approval of our shareholders. These additional shares may be utilized for a variety of purposes, including future public offerings to raise additional capital or to fund acquisitions. The existence of authorized but unissued shares could render more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

In addition, our board of directors has broad authority to amend the LLC agreement, as discussed below. The board could, in the future, choose to amend the LLC agreement to include other provisions which have the intention or effect of discouraging takeover attempts.

Disclosure Requirements Applicable to Fifteen Percent Investors

A certain number of our investors may be required to comply with certain disclosure requirements of the City of Chicago and non-compliance may result in the City of Chicago’s rescission or voidance of the Use Agreement and any other arrangements District Energy may have with the City of Chicago at the time of the non-compliance.

In order to secure any amendment to the Use Agreement with the City of Chicago to pursue expansion plans or otherwise, or to enter into other contracts with the City of Chicago, the City of Chicago may require any person who owns or acquires 15% or more of our shares to make a number of representations to the City of Chicago by filing a completed Economic Disclosure Statement, or EDS. The LLC agreement requires that in the event that we need to obtain approval from the City of Chicago in the future for any specific matter, including to expand the district cooling system or to amend the Use Agreement, we and each of our then 15% investors would need to submit an EDS to the City of Chicago within 30 days of the City of Chicago’s

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request. In addition, the LLC agreement requires each 15% investor to provide any supplemental information needed to update any EDS filed with the City of Chicago as required by the City of Chicago and as requested by us from time to time.

Any EDS filed by an investor may become publicly available. By completing and signing an EDS, an investor will have waived and released any possible rights or claims which it may have against the City of Chicago in connection with the public release of information contained in the EDS and also will have authorized the City of Chicago to verify the accuracy of information submitted in the EDS. The requirements and consequences of filing an EDS with the City of Chicago will make compliance with the EDS requirements difficult for our investors.

If any investor fails to comply with the EDS requirements on time or the City of Chicago determines that any information provided in any EDS is false, incomplete or inaccurate, the City of Chicago may rescind or void the Use Agreement or any other arrangements Thermal Chicago has with the City of Chicago, and pursue any other remedies available to them.

Amendment of the LLC Agreement

The LLC agreement may be amended by a majority vote of our board of directors, except with respect to the following provisions, which effectively require an affirmative vote of at least a majority of the outstanding shares:

In addition, the consent of our Manager is required to amend the provisions providing for the duties of our Manager and the secondment of our officers pursuant to the management services agreement, the provision entitling our Manager to appoint the director who will serve as the chairman of our board of directors for so long as the management services agreement is in effect and the provision of the LLC agreement governing amendments thereof.

Transfer Agent and Registrar

The transfer agent and registrar for our shares is Computershare Trust Company, N.A.

Listing

Our shares are listed on the NYSE under the symbol “MIC.”

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DESCRIPTION OF DEBT SECURITIES

Senior and Subordinated Debt Securities

As used in this prospectus, debt securities means the debentures, notes, bonds and other evidences of indebtedness that we may issue from time to time. The debt securities will either be senior debt securities or subordinated debt securities. Senior debt securities will be issued under a senior indenture to be entered into between us and Wells Fargo Bank, National Association, as trustee, and subordinated debt securities will be issued under a subordinated indenture, to be entered into between us and Wells Fargo Bank, National Association, as trustee. This prospectus sometimes refers to the senior indenture and the subordinated indenture collectively as the indentures. Forms of the senior indenture and the subordinated indenture have been filed as exhibits to the registration statement of which this prospectus forms a part.

We may also issue debt securities under a separate, new indenture. If that occurs, we will describe any differences in the terms of any series or issue of debt securities in the prospective supplement relating to that series or issue.

The statements and descriptions in this prospectus or in any prospectus supplement regarding provisions of the indentures and debt securities are summaries thereof, do not purport to be complete and are subject to, and are qualified in their entirety by reference to, all of the provisions of the indentures (and any amendments or supplements we may enter into from time to time as permitted under each indenture) and the debt securities, including the definitions therein of certain terms.

As used in this “Description of Debt Securities,” the terms “the company,” “we,” “our” and “us” refer to Macquarie Infrastructure Company LLC, a Delaware limited liability company, and do not, unless otherwise provided, include subsidiaries of Macquarie Infrastructure Company LLC.

General

Unless otherwise specified in a prospectus supplement, the debt securities will be direct unsecured obligations of the company. The senior debt securities will rank equally with any of our other unsecured senior and unsubordinated debt. The subordinated debt securities will be subordinate and junior in right of payment to any senior debt, as defined, and described more fully, under “— Subordination,” to the extent and in the manner set forth in the subordinated indenture.

The indentures will not limit the aggregate principal amount of debt securities that we may issue and provide that we may issue debt securities from time to time in one or more series, in each case with the same or various maturities, at par or at a discount. Unless indicated in a prospectus supplement, we may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series outstanding at the time of the issuance. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of debt securities under the applicable indenture and will be equal in ranking.

In the event that our secured creditors, if any, exercise their rights with respect to our assets pledged to them, our secured creditors would be entitled to be repaid in full from the proceeds of those assets before those proceeds would be available for distribution to our other creditors, including the holders of debt securities of any series.

The company’s subsidiaries are separate and distinct legal entities and have no obligation, contingent or otherwise, to pay any amounts due pursuant to the debt securities of any series or to make any funds available to the company, whether by dividend, loan or other payment, unless such subsidiaries guarantee the debt securities issued by the company. Therefore, without such guarantees, the assets of the company’s subsidiaries will be subject to the prior claims of all their respective creditors, including the lenders under any credit facilities or debt instruments maintained by our subsidiaries and trade creditors of our subsidiaries. The payment of dividends or the making of loans or advances to the company by its subsidiaries may be subject to contractual, statutory or regulatory restrictions, are contingent upon the earnings of those subsidiaries and are subject to various business considerations.

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Prospectus Supplement

Each prospectus supplement will describe the terms relating to the specific series of debt securities being offered. These terms will include some or all of the following:

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Each prospectus supplement, if required, will describe the material U.S. federal income tax considerations associated with the purchase, ownership and disposition by U.S. holders and non-U.S. holders (in each case, as defined under the heading “Material U.S. Federal Income Tax Considerations”) relating to the specific series of debt securities offered.

Unless otherwise specified in a prospectus supplement, the debt securities will not be listed on any securities exchange and will be issued in fully-registered form without coupons.

Holders of the debt securities may present their securities for exchange and may present registered debt securities for transfer in the manner described in the applicable prospectus supplement. Except as limited by the applicable indenture, we will provide these services without charge, other than any tax or other governmental charge payable in connection with the exchange or transfer.

Debt securities may bear interest at a fixed rate or a variable rate, as specified in the prospectus supplement. In addition, if specified in the prospectus supplement, we may sell debt securities bearing no interest or interest at a rate that at the time of issuance is below the prevailing market rate, or at a discount below their stated principal amount. We will describe in the prospectus supplement any special federal income tax considerations applicable to these discounted debt securities.

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Subordination

The prospectus supplement relating to any offering of subordinated debt securities will describe the specific subordination provisions. However, unless otherwise noted in the prospectus supplement, subordinated debt securities will be subordinate and junior in right of payment to any existing senior debt of the company.

The terms of the subordination of a series of subordinated securities, together with the definition of senior debt related thereto, will be as set forth in the applicable supplemental indenture and the prospectus supplement relating to such series.

Our creditors who do not hold senior debt will not benefit from the subordination provisions described herein. In the event of our bankruptcy or insolvency before or after maturity of the subordinated securities, such other creditors would rank equally and ratably with holders of the subordinated securities, subject, however, to the broad equity powers of the Federal bankruptcy court pursuant to which such court may, among other things, reclassify the claims of any series of subordinated securities into a class of claims having a different relative priority with respect to the claims of such other creditors or any other claims against us.

Except to the extent otherwise set forth in a prospectus supplement, the indentures do not contain any restriction on the amount of senior debt which we may incur.

Restrictive Covenants

We will describe any restrictive covenants for any series of debt securities in the prospectus supplement and/or other offering material for each offering of such debt securities.

Consolidation, Merger, Sale of Assets and Other Transactions

Unless otherwise noted in a prospectus supplement, we will not merge with or into or consolidate with any other person or sell, assign, transfer or convey our properties and assets substantially as an entirety to any other person other than a direct or indirect wholly-owned subsidiary of ours, unless:

Events of Default, Notice and Waiver

Unless a prospectus supplement states otherwise, the following shall constitute events of default under the indentures with respect to each series of debt securities:

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If an event of default with respect to any debt securities of any series outstanding under either of the indentures shall occur and be continuing, the trustee under such indenture or the holders of at least 25% in aggregate principal amount of the debt securities of that series outstanding may declare, by notice as provided in the applicable indenture, the principal amount (or such lesser amount as may be provided for in the debt securities of that series) of all the debt securities of that series outstanding to be due and payable immediately; provided that, in the case of an event of default involving certain events in bankruptcy, insolvency or reorganization, acceleration is automatic; and, provided further, that after such acceleration, but before a judgment or decree based on acceleration, the holders of a majority in aggregate principal amount of the outstanding debt securities of that series may, under certain circumstances, rescind and annul such acceleration if all events of default, other than the nonpayment of accelerated principal, have been cured or waived. Upon the acceleration of the maturity of original issue discount securities, an amount less than the principal amount thereof will become due and payable. Reference is made to the prospectus supplement relating to any original issue discount securities for the particular provisions relating to acceleration of maturity thereof.

Any past default under either indenture with respect to debt securities of any series, and any event of default arising therefrom, may be waived by the holders of a majority in principal amount of all debt securities of such series outstanding under such indenture, except in the case of (1) default in the payment of the principal of (or premium, if any) or interest on any debt securities of such series or (2) default in respect of a covenant or provision which may not be amended or modified without the consent of the holder of each outstanding debt security of such series affected.

The trustee is required within 90 days after the occurrence of an event of default (which is known to the trustee and is continuing), with respect to the debt securities of any series (without regard to any grace period or notice requirements), to give to the holders of the debt securities of such series notice of such event of default.

The trustee, subject to its duties during an event of default to act with the required standard of care, may require indemnification satisfactory to the trustee by the holders of the debt securities of any series with respect to which an event of default has occurred before proceeding to exercise any right or power under the indentures at the request of the holders of the debt securities of such series. Subject to such right of indemnification and to certain other limitations, the holders of a majority in principal amount of the outstanding debt securities of any series under either indenture may direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee with respect to the debt securities of such series, provided that such direction shall not be in conflict with any rule of law or with the applicable indenture and the trustee may take any other action deemed proper by the trustee which is not inconsistent with such direction.

No holder of a debt security of any series may institute any action against us under either of the indentures (except actions for payment of overdue principal of (and premium, if any) or interest on such debt security or for the conversion or exchange of such debt security in accordance with its terms) unless:

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We are required to furnish periodically to the trustee statements as to our compliance with all conditions and covenants under each indenture.

Discharge, Defeasance and Covenant Defeasance

We may discharge or defease our obligations under the indenture as set forth below, unless otherwise indicated in a prospectus supplement.

We may discharge certain obligations to holders of any series of debt securities issued under either the senior indenture or the subordinated indenture which have not already been delivered to the trustee for cancellation and which have either become due and payable or are by their terms due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with the trustee money in an amount sufficient to pay and discharge the entire indebtedness on such debt securities not previously delivered to the trustee for cancellation, for principal and any premium and interest to the date of such deposit (in the case of debt securities which have become due and payable) or to the stated maturity or redemption date, as the case may be, and we have paid all other sums payable under the applicable indenture.

If indicated in a prospectus supplement, we may elect either (1) to defease and be discharged from any and all obligations with respect to the debt securities of or within any series (except as otherwise provided in the relevant indenture) (referred to as defeasance) or (2) to be released from our obligations with respect to certain covenants applicable to the debt securities of or within any series (referred to as covenant defeasance), upon the deposit with the relevant indenture trustee, in trust for such purpose, of money and/or government obligations which through the payment of principal and interest in accordance with their terms will provide money in an amount sufficient (in the opinion of an independent registered accounting firm) to pay the principal of (and premium, if any) or interest on such debt securities to maturity or redemption, as the case may be, and any mandatory sinking fund or analogous payments thereon. As a condition to defeasance or covenant defeasance, we must deliver to the trustee an opinion of counsel to the effect that the holders of such debt securities will not recognize income, gain or loss for federal income tax purposes as a result of such defeasance or covenant defeasance and will be subject to federal income tax on the same amounts and in the same manner and at the same times as would have been the case if such defeasance or covenant defeasance had not occurred. Such opinion of counsel, in the case of defeasance under clause (1) above, must refer to and be based upon a ruling of the Internal Revenue Service, or IRS, or a change in applicable federal income tax law occurring after the date of the relevant indenture. In addition, in the case of either defeasance or covenant defeasance, we must deliver to the trustee an officers’ certificate and an opinion of counsel, each stating that all conditions precedent with respect to such defeasance or covenant defeasance have been complied with.

We may exercise our defeasance option with respect to such debt securities notwithstanding our prior exercise of our covenant defeasance option.

Modification and Waiver

Under the indentures, we and the applicable trustee may supplement the indentures for certain purposes without the consent of those holders. We and the applicable trustee may also modify the indentures or any supplemental indenture in a manner that affects the interests or rights of the holders of debt securities with the consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each affected series issued under the indenture. However, the indentures require the consent of each holder of debt securities that would be affected by any modification which would:

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The indentures permit the holders of at least a majority in aggregate principal amount of the outstanding debt securities of any series issued under the indentures which is affected by the modification or amendment to waive our compliance with certain covenants contained in the indentures.

Payment and Paying Agents

Unless otherwise indicated in the applicable prospectus supplement, payment of interest on a debt security on any interest payment date will be made to the person in whose name a debt security is registered at the close of business on the record date for the interest.

Unless otherwise indicated in the applicable prospectus supplement, principal, interest and premium on the debt securities of a particular series will be payable at the office of such paying agent or paying agents as we may designate for such purpose from time to time. Notwithstanding the foregoing, at our option, payment of any interest may be made by check mailed to the address of the person entitled thereto as such address appears in the security register.

Unless otherwise indicated in the applicable prospectus supplement, a paying agent designated by us will act as paying agent for payments with respect to debt securities of each series. All paying agents initially designated by us for the debt securities of a particular series will be named in the applicable prospectus supplement. We may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts, except that we will be required to maintain a paying agent in each place of payment for the debt securities of a particular series.

All monies paid by us to a paying agent for the payment of the principal, interest or premium on any debt security which remain unclaimed at the end of two years after such principal, interest or premium has become due and payable will be repaid to us upon request, and the holder of such debt security shall thereafter, as an unsecured general creditor, look only to us for payment thereof.

Global Debt Securities

We may issue registered debt securities in global form. This means that one “global” debt security would be issued to represent a number of registered debt securities. The denomination of the global debt security would equal the aggregate principal amount of all registered debt securities represented by that global debt security.

We will deposit any registered debt securities issued in global form with a depositary, or with a nominee of the depositary, that we will name in the applicable prospectus supplement for each offering of such debt securities. Any person holding an interest in the global debt security through the depositary will be considered the “beneficial” owner of that interest. A “beneficial” owner of a security is able to enjoy rights associated with ownership of the security, even though the beneficial owner is not recognized as the legal owner of the security. The interest of the beneficial owner in the security is considered the “beneficial interest.” We will register the debt securities in the name of the depositary or the nominee of the depositary, as appropriate.

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The depositary or its nominee may only transfer a global debt security in its entirety and only in the following circumstances:

These restrictions on transfer would not apply to a global debt security after the depositary or its nominee, as applicable, exchanged the global debt security for registered debt securities issued in definitive form.

We will describe the specific terms of the depositary arrangement with respect to any series of debt securities represented by a registered global security in the prospectus supplement for the offering of that series. We anticipate that the following provisions will apply to all depositary arrangements for debt securities represented by a registered global security.

Ownership of beneficial interests in a registered global security will be limited to (1) participants that have accounts with the depositary for the registered global security and (2) persons that may hold interests through those participants. Upon the issuance of a registered global security, the depositary will credit each participant’s account on the depositary’s book-entry registration and transfer system with the principal amount of debt securities represented by the registered global security beneficially owned by that participant. Initially, the dealers, underwriters or agents participating in the distribution of the debt securities will designate the accounts that the depositary should credit.

Ownership of beneficial interests in the registered global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary for the registered global security, with respect to interests of participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some states may require that purchasers of securities regulated by the laws of those states take physical delivery of the securities in definitive form. Those laws may impair the ability to own, transfer or pledge beneficial interests in registered global securities.

As long as the depositary for a registered global security, or its nominee, is the registered owner of the registered global security, that depositary or its nominee will be considered the sole owner or holder of the debt securities represented by the registered global security for all purposes under the applicable indenture. Owners of beneficial interests in a registered global security generally will not:

Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for the registered global security and, if that person owns through a participant, on the procedures of the participant through which that person owns its interest, to exercise any rights of a holder under the applicable indenture.

We understand that under existing industry practices, if we request any action of holders of debt securities or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder of debt securities is entitled to give or take under the applicable indenture, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take the action, and the participants would authorize beneficial owners owning through the participants to give or take the action or would otherwise act upon the instructions of beneficial owners owning through them.

We will make payments of principal, any premium and any interest on a registered global security to the depositary or its nominee. None of the company, the trustee or any other agent of the company or of the

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trustee will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to the beneficial ownership interests.

We expect that the depositary for any registered global security, upon receipt of any payment of principal (or premium, if any) or interest in respect of the registered global security, will immediately credit participants’ accounts with payments in amounts proportionate to their respective beneficial interests in the registered global security as shown on the records of the depositary.

We also expect that standing customer instructions and customary practices will govern payments by participants to owners of beneficial interests in the registered global security owned through the participants.

We will issue our debt securities in definitive form in exchange for a registered global security, if the depositary for such registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act and if a successor depositary registered as a clearing agency under the Exchange Act is not appointed within 90 days and under such other circumstances, if any, as may be described in an applicable prospectus supplement. In addition, we may at any time and in our sole discretion determine not to have any of the debt securities of a series represented by a registered global security and, in such event, will issue debt securities of the series in definitive form in exchange for the registered global security.

We will register any debt securities issued in definitive form in exchange for a registered global security in such name or names as the depositary shall instruct the trustee. We expect that the depositary will base these instructions upon directions received by the depositary from participants with beneficial interests in the registered global security.

Governing Law

The indentures and the debt securities will be governed by, and construed in accordance with, the laws of the State of New York. The indentures are subject to the provisions of the Trust Indenture Act that are required to be part of the indenture and shall, to the extent applicable, be governed by such provisions.

Concerning the Trustee

We anticipate appointing Wells Fargo Bank, National Association, the trustee under the indentures, as the paying agent, registrar and custodian with regard to the debt securities. As of the date of this prospectus, the trustee and its affiliates and Macquarie Infrastructure Company LLC and its affiliates may have various business relationships. In addition, as of the date of this prospectus, the trustee and its affiliates and the Macquarie Group and its affiliates, including the Manager, may have various business relationships. The trustee or its affiliates may in the future provide banking and other services to us and our subsidiaries, and to the Macquarie Group and its affiliates, including the Manager, in the ordinary course of their respective businesses.

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MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS

The following discussion describes the material U.S. federal income tax considerations associated with the purchase, ownership and disposition of our shares by U.S. holders (as defined below) and non-U.S. holders (as defined below). Except where noted, this discussion deals only with the shares held as capital assets by holders who acquired the shares in this issuance and does not address special situations, such as those of:

This discussion does not address the material U.S. federal income tax considerations associated with the purchase, ownership and disposition of debt securities which will be set forth, if required, in the applicable prospectus supplement.

Furthermore, the discussion below is based upon the provisions of the Code, the Regulations, and administrative and judicial interpretations thereof, all as of the date hereof, and such authorities may be repealed, revoked, modified or subject to differing interpretations, possibly on a retroactive basis, so as to result in U.S. federal income tax consequences different from those described below.

A “U.S. holder” of our shares means a beneficial owner of our shares that is for U.S. federal income tax purposes:

A “non-U.S. holder” of our shares means a beneficial owner of our shares that is an individual, a corporation, an estate or a trust that is neither a U.S. holder nor a partnership (or other entity taxable as a partnership).

If a partnership or other entity or arrangement treated as a partnership for U.S. federal income tax purposes holds our shares, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. If you are a partner of a partnership holding our shares, we urge you to consult your own tax adviser.

We cannot assure you that the IRS, or the courts will agree with the tax consequences described herein. A different treatment from that described below could adversely affect the amount, timing and character of income, gain or loss in respect of an investment in our shares. If you are considering the purchase of our shares, we urge you to consult your own tax adviser concerning the particular U.S. federal income tax

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consequences to you of the purchase, ownership and disposition of our shares, as well as any consequences to you arising under the laws of any other taxing jurisdiction.

U.S. Holders

The following discussion summarizes the material U.S. federal income tax consequences of the ownership and disposition of our shares applicable to U.S. holders, subject to the limitations described above.

No Flow-Through of Taxable Income

An election has been made with the IRS to treat us as an association taxable as a corporation for U.S. federal income tax purposes. Because we are treated as an association taxable as a corporation for U.S. federal income tax purposes, an owner of our shares will not report on its U.S. federal income tax return any of our items of income, gain, loss and deduction.

Distributions

Distributions of cash or property that we pay in respect of our shares will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits (as determined under U.S. federal income tax principles) and will be includible in gross income by a U.S. holder upon receipt. Any such dividend will be eligible for the dividends received deduction if received by an otherwise qualifying corporate U.S. holder that meets the holding period and other requirements for the dividends received deduction. Dividends paid by us to certain non-corporate U.S. holders (including individuals) are eligible for U.S. federal income taxation at the rates generally applicable to long-term capital gains for individuals (currently at a maximum tax rate of 20%), provided that the U.S. holder receiving the dividend satisfies the applicable holding period and other requirements. If the amount of a distribution exceeds our current and accumulated earnings and profits, such excess first will be treated as a tax-free return of capital to the extent of the U.S. holder’s tax basis in our shares, and thereafter will be treated as capital gain.

Dispositions

Upon a sale, exchange or other taxable disposition of our shares, a U.S. holder generally will recognize capital gain or loss equal to the difference between the amount realized on the sale, exchange or other taxable disposition and the U.S. holder’s adjusted tax basis in our shares. Such capital gain or loss will be long-term capital gain or loss if the U.S. holder has held the shares for more than one year at the time of disposition. Long-term capital gains of certain non-corporate U.S. holders (including individuals) are currently subject to U.S. federal income taxation at a maximum rate of 20%. The deductibility of capital losses is subject to limitations under the Code.

Medicare Tax on Investment Income

For taxable years beginning after December 31, 2012, certain U.S. holders who are individuals, estates, or trusts will be subject to a 3.8% Medicare tax on the lesser of (1) the U.S. holder’s “net investment income” for the relevant taxable year and (2) the excess of the U.S. holder’s modified adjusted gross income for the taxable year over a certain threshold (which in the case of individuals will be between $125,000 and $250,000, depending on the individual’s circumstances). A U.S. holder’s net investment income will generally include its dividend income and its gains from the disposition of our shares, unless such dividend income or net gains are derived in the ordinary course of the conduct of a trade or business (other than a trade or business that consists of certain passive or trading activities). If you are a U.S. holder that is an individual, estate, or trust, you are urged to consult your own tax advisors regarding the applicability of the Medicare tax to your income and gains in respect of your investment in our shares.

Information Reporting and Backup Withholding Requirements

In general, dividends on our shares, and payments of the proceeds of a sale, exchange or other taxable disposition of our shares paid to a U.S. holder are subject to information reporting and may be subject to backup withholding at a current maximum rate of 28% unless the U.S. holder (i) is a corporation or other exempt recipient or (ii) provides an accurate taxpayer identification number and certifies that it is not subject to backup withholding.

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Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a U.S. holder will be refunded by the IRS or credited against the U.S. holder’s U.S. federal income tax liability, if any, provided that the required information is furnished to the IRS.

Non-U.S. Holders

The following discussion summarizes the material U.S. federal income tax consequences of the ownership and disposition of our shares applicable to non-U.S. holders, subject to the limitations described above.

U.S. Trade or Business Income

For purposes of this discussion, dividend income and gain on the sale, exchange or other taxable disposition of our shares will be considered to be “U.S. trade or business income” if such income or gain is (i) effectively connected with the conduct by a non-U.S. holder of a trade or business within the United States and (ii) in the case of a non-U.S. holder that is eligible for the benefits of an income tax treaty with the United States, attributable to a permanent establishment (or, for an individual, a fixed base) maintained by the non-U.S. holder in the United States. Generally, U.S. trade or business income is not subject to U.S. federal withholding tax (provided the non-U.S. holder complies with applicable certification and disclosure requirements); instead, a non-U.S. holder is subject to U.S. federal income tax on a net income basis at regular graduated U.S. federal income tax rates (in the same manner as a U.S. person) on its U.S. trade or business income. Any U.S. trade or business income received by a non-U.S. holder that is a corporation also may be subject to a “branch profits tax” at a 30% rate (or lower treaty rate, if applicable) on its effectively connected earnings and profits that are not timely reinvested in a U.S. trade or business.

Distributions

Distributions of cash or property that we pay in respect of our shares will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits (as determined under U.S. federal income tax principles). A non-U.S. holder generally will be subject to U.S. federal withholding tax at a 30% rate, or at a reduced rate prescribed by an applicable income tax treaty, on any dividends received in respect of our shares. If the amount of a distribution exceeds our current and accumulated earnings and profits, such excess first will be treated as a tax-free return of capital to the extent of the non-U.S. holder’s tax basis in our shares, and thereafter will be treated as capital gain (and thus treated in the manner described in “— Dispositions” below). In order to obtain a reduced rate of U.S. federal withholding tax under an applicable income tax treaty, a non-U.S. holder will be required to provide a properly executed IRS Form W-8BEN certifying its entitlement to benefits under the treaty. A non-U.S. holder of our shares that is eligible for a reduced rate of U.S. federal withholding tax under an income tax treaty may obtain a refund or credit of any excess amounts withheld by filing an appropriate claim for a refund with the IRS. A non-U.S. holder should consult its own tax advisor regarding its possible entitlement to benefits under an income tax treaty.

The U.S. federal withholding tax described in the preceding paragraph does not apply to dividends that represent U.S. trade or business income of a non-U.S. holder who provides a properly executed IRS Form W-8ECI, certifying that the dividends are effectively connected with the non-U.S. holder’s conduct of a trade or business within the United States.

Dispositions

Except as set forth below, a non-U.S. holder generally will not be subject to U.S. federal income or withholding tax in respect of any gain on a sale, exchange or other taxable disposition of our shares unless:

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We have not determined whether we are a U.S. real property holding corporation, and no assurance can be given that we are not or will not become one in the future. If, however, we are or become a U.S. real property holding corporation, so long as our shares are regularly traded on an established securities market, generally only a non-U.S. holder who holds or held directly or indirectly (at any time during the shorter of the five year period ending on the date of disposition or the non-U.S. holder’s holding period) more than five percent of our shares will be subject to United States federal income tax on the disposition of our shares. Non-U.S. holders should consult their own advisors about the consequences that could result if we are, or become, a U.S. real property holding corporation.

Information Reporting and Backup Withholding Requirements

We must annually report to the IRS and to each non-U.S. holder any dividend income that is subject to U.S. federal withholding tax, or that is exempt from such withholding tax pursuant to an income tax treaty. Copies of these information returns also may be made available under the provisions of a specific treaty or agreement to the tax authorities of the country in which the non-U.S. holder resides. Under certain circumstances, the Code imposes a backup withholding obligation (currently at a rate of 28%) on certain reportable payments. Dividends paid to a non-U.S. holder of our shares generally will be exempt from backup withholding if the non-U.S. holder provides a properly executed IRS Form W-8BEN or otherwise establishes an exemption.

The payment of the proceeds from the disposition of our shares to or through the U.S. office of any broker, U.S. or foreign, will be subject to information reporting and possible backup withholding unless the owner certifies as to its non-U.S. status under penalties of perjury or otherwise establishes an exemption, provided that the broker does not have actual knowledge or reason to know that the holder is a U.S. person or that the conditions of any other exemption are not, in fact, satisfied. The payment of the proceeds from the disposition of our shares to or through a non-U.S. office of a non-U.S. broker will not be subject to information reporting or backup withholding unless the non-U.S. broker has certain types of relationships with the United States (a “U.S. related person”). In the case of the payment of the proceeds from the disposition of our shares to or through a non-U.S. office of a broker that is either a U.S. person or a U.S. related person, the Regulations require information reporting (but not backup withholding) on the payment unless the broker has documentary evidence in its files that the owner is a non-U.S. holder and the broker has no knowledge to the contrary. Non-U.S. holders should consult their own tax advisors on the application of information reporting and backup withholding to them in their particular circumstances (including upon their disposition of our shares).

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder will be refunded by the IRS or credited against the non-U.S. holder’s U.S. federal income tax liability, if any, provided that the required information is furnished to the IRS.

Non-U.S. holders are advised to consult their own tax advisers with respect to the particular tax consequences to them of an investment in us.

Federal Estate Tax

Our shares beneficially owned by an individual who is not a citizen or resident of the U.S. (as defined for U.S. federal estate tax purposes) at the time of death will generally be includable in the decedent’s gross estate for U.S. federal estate tax purposes, unless an applicable estate tax treaty provides otherwise.

U.S. Foreign Account Tax Compliance Act Withholding

Pursuant to Sections 1471 to 1474 of the Code and the Regulations promulgated thereunder, or FACTA, dividends paid after December 31, 2013 and the gross proceeds of sale or other disposition of our shares after December 31, 2016, to a foreign financial institution may be subject to withholding at the rate of 30% unless such institution enters into an agreement with the U.S. government to withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners). The legislation also generally will impose a U.S. federal withholding tax of 30% on dividends on, and the gross proceeds of a sale or other disposition of, our shares

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paid after December 31, 2013 (or in the case of gross proceeds from a sale or other disposition, December 31, 2016), to a non-financial foreign entity unless such entity provides the withholding agent with a certification (i) that such entity does not have any “substantial United States owners” or (ii) provides certain information regarding the entity’s “substantial United States owners,” which will in turn be provided to the U.S. tax authorities. Under certain circumstances, a U.S. holder or non-U.S. holder might be eligible for refunds or credits of such taxes. Prospective investors are encouraged to consult with their own tax advisors regarding the possible implications of this legislation on their investment in our shares.

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SELLING SECURITY HOLDER

The Selling Security Holder is a member of the Macquarie Group, a diversified international provider of financial, advisory and investment services. The Macquarie Group is headquartered in Sydney, Australia and is a global leader in management of infrastructure investment vehicles on behalf of third-party investors and advising on the acquisition, disposition and financing of infrastructure assets. The Selling Security Holder may from time to time offer and sell pursuant to this prospectus any or all of the shares beneficially owned by it.

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PLAN OF DISTRIBUTION

Sales of our securities

We may sell the securities offered by us pursuant to this prospectus and any accompanying prospectus supplements separately or together:

We may sell the securities offered by us pursuant to this prospectus and any accompanying prospectus supplements to or through one or more underwriters or dealers or we may sell the securities to investors directly or through agents. Each prospectus supplement, to the extent applicable, will describe the number and terms of the securities to which such prospectus supplement relates, the name or names of any underwriters or agents with whom we have entered into arrangements with respect to the sale of such securities, the public offering or purchase price of such securities and the net proceeds we will receive from such sale. Any underwriter or agent involved in the offer and sale of the securities will be named in the applicable prospectus supplement. We may sell securities directly to investors on our own behalf in those jurisdictions where we are authorized to do so.

Underwriters may offer and sell the securities at a fixed price or prices, which may be changed from time to time, at market prices prevailing at the time of sale, at prices related to the prevailing market prices or at negotiated prices. We also may, from time to time, authorize dealers or agents to offer and sell these securities upon such terms and conditions as may be set forth in the applicable prospectus supplement. In connection with the sale of any of these securities, underwriters may receive compensation from us in the form of underwriting discounts or commissions and may also receive commissions from purchasers of the securities for whom they may act as agent. Underwriters may sell the securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters or commissions from the purchasers for which they may act as agents. The obligations of the underwriters to purchase securities will be subject to the conditions set forth in the applicable underwriting agreement.

Securities may also be sold in one or more of the following transactions: (a) block transactions (which may involve crosses) in which a broker-dealer may sell all or a portion of the securities as agent but may position and resell all or a portion of the block as principal to facilitate the transaction; (b) purchases by a broker-dealer as principal and resale by the broker-dealer for its own account pursuant to a prospectus supplement; (c) a special offering, an exchange distribution or a secondary distribution in accordance with applicable New York Stock Exchange or other stock exchange rules; (d) ordinary brokerage transactions and transactions in which a broker-dealer solicits purchasers; (e) sales “at the market” to or through one or more market makers or into an existing trading market, on an exchange or otherwise, for securities; and (f) sales in other ways not involving market makers or established trading markets, including direct sales to purchasers. Broker-dealers may also receive compensation from purchasers of the securities which is not expected to exceed that customary in the types of transactions involved.

In addition, the Selling Security Holder may sell shares under this prospectus in any of these ways. The Selling Security Holder will act independently of us in making decisions with respect to the timing, manner and size of each sale. The Selling Security Holder may also sell shares of our shares under Rule 144 under the Securities Act of 1933, as amended, or the Securities Act, if available, rather than under this prospectus.

We will set forth in a prospectus supplement the terms of the offering of securities, including:

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If we or the Selling Security Holder use underwriters for a sale of securities, the underwriters will acquire the securities for their own account. The underwriters may resell the securities in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. The underwriters will be obligated to purchase all the securities of the series offered if they purchase any of the securities of that series. We may use underwriters with whom we have a material relationship. We will describe in the prospectus supplement naming the underwriters the nature of any such relationship.

Underwriters, dealers or agents may receive compensation in the form of discounts, concessions or commissions from us, the Selling Security Holder or from our purchasers (as their agents in connection with the sale of securities). These underwriters, dealers or agents may be considered to be underwriters under the Securities Act. As a result, discounts, commissions or profits on resale received by the underwriters, dealers or agents may be treated as underwriting discounts and commissions. The prospectus supplement accompanying this prospectus will identify any such underwriter, dealer or agent, and describe any compensation received by them from us or the Selling Security Holder. Pursuant to a requirement by the Financial Industry Regulatory Authority, or FINRA, the maximum commission or discount to be received by a FINRA member or independent broker-dealer may not be greater than 8% of the gross proceeds received by the Selling Security Holder for the sale of any shares being registered pursuant to Rule 415 under the Security Act. Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis and a dealer will purchase securities as a principal, and may then resell the securities at varying prices to be determined by the dealer.

Underwriters, dealers and agents may be entitled to indemnification by us or the Selling Security Holder against certain civil liabilities, including liabilities under the Securities Act, or to contribution with respect to payments made by the underwriters, dealers or agents, under agreements between us or the Selling Security Holder and the underwriters, dealers and agents.

We or the Selling Security Holder may grant underwriters who participate in the distribution of securities an option to purchase additional securities in connection with the distribution.

To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain, or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involve the sale by persons participating in the offering of more securities than we or the Selling Security Holder sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their option, if any, to purchase additional securities. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions, if commenced, may be discontinued at any time.

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The Selling Security Holder and any other person participating in a distribution of the securities covered by this prospectus will be subject to the applicable provisions of the Exchange Act and the rules and regulations thereunder. Regulation M of the Exchange Act may limit the timing of purchases and sales of securities by the Selling Security Holder and any other person. In addition, Regulation M may restrict the ability of any person engaged in the distribution of the securities to engage in market-making activities with respect to our securities for a period of up to five business days before the distribution.

In the ordinary course of business activities, any underwriters and their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the account of their customers and may at any time hold long and short positions in such securities and instruments. Such instruments may involve securities and instruments of the Company.

LEGAL MATTERS

Certain legal matters in connection with the securities offered hereby will be passed upon for us by White & Case LLP, New York, New York.

EXPERTS

The consolidated financial statements and schedule of Macquarie Infrastructure Company LLC and subsidiaries as of December 31, 2012 and 2011, and for each of the years in the three-year period ended December 31, 2012, and management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2012, have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The consolidated financial statements of IMTT Holdings Inc. and subsidiaries as of December 31, 2012 and 2011, and for each of the years then ended, have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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5,312,500 Shares
  

Macquarie Infrastructure Company LLC   

Prospectus Supplement
February 25, 2015

Barclays
Macquarie Capital
J.P. Morgan
RBC Capital Markets
SunTrust Robinson Humphrey

 

Oppenheimer & Co.
Wells Fargo Securities
BofA Merrill Lynch
BBVA
BB&T Capital Markets
Credit Agricole CIB
JonesTrading Capital Markets
Regions Securities LLC