UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

SUN HYDRAULICS CORPORATION

(Exact name of registrant as specified in its charter)

1500 WEST UNIVERSITY PARKWAY

SARASOTA, FLORIDA 34243

(941) 362-1200

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Wolfgang H. Dangel

President and Chief Executive Officer

1500 WEST UNIVERSITY PARKWAY

SARASOTA, FLORIDA 34243

(941) 362-1200

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Gregory C. Yadley, Esq.

Shumaker, Loop & Kendrick, LLP

101 E. Kennedy Blvd., Ste. 2800

Tampa, Florida 33602

(813) 229-7600

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ☒

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for comply with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

PROSPECTUS

Sun Hydraulics Corporation

Common Stock

We may offer and sell the shares of common stock identified above, in each case from time to time in one or more offerings. This prospectus provides you with a general description of the securities.

Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering as well as the amounts, prices and terms of the securities. The supplement may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and the applicable prospectus supplement, together with the documents we incorporate by reference, before you invest in any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers or agents are involved in the sale of any of the securities, then their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections of this prospectus entitled “About this Prospectus” and “Plan of Distribution” for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

Our common stock is listed on the Nasdaq Stock Global Select Market under the symbol “SNHY.” The last reported sale price of our common on the Nasdaq Global Select Market on January 26, 2018 was $69.81 per share.

INVESTING IN OUR SECURITIES INVOLVES RISKS. SEE THE “RISK FACTORS” ON PAGE 5 OF THIS PROSPECTUS AND ANY SIMILAR SECTION CONTAINED IN THE APPLICABLE PROSPECTUS SUPPLEMENT CONCERNING FACTORS YOU SHOULD CONSIDER BEFORE INVESTING IN OUR SECURITIES. YOU SHOULD ALSO REFER TO THE RISK FACTORS INCLUDED IN OUR PERIODIC REPORTS THAT WE FILE WITH THE SECURITIES AND EXCHANGE COMMISSION.

Neither the Securities and Exchange Commission nor any other regulatory body 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 January 29, 2018

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

Whenever we refer to “Sun,” the “Company,” “we,” “our” or “us” in this prospectus, we mean SUN HYDRAULICS CORPORATION and its consolidated subsidiaries, unless the context otherwise requires. When we refer to “you” or “yours,” we mean the holders of our common stock.

This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange Commission (the “SEC”) as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended (the “Securities Act”) using a “shelf” registration process. By using a shelf registration statement, we may sell the securities described in this prospectus from time to time and in one or more offerings. Each time that we offer securities, we will attach a prospectus supplement to this prospectus. The prospectus supplement may also add, update or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement, you should rely on the prospectus supplement. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement, together with the additional information described under the heading “Where You Can Find More Information.”

You should rely only on the information contained in this prospectus, in an accompanying prospectus supplement or incorporated by reference herein or therein. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus and any accompanying prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities other than the registered securities to which they relate, and this prospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction where, or to any person to whom, it is unlawful to make such an offer or solicitation. You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate as of the date on its respective cover, and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates.

SUN HYDRAULICS CORPORATION

Sun, founded in 1970, in Sarasota, Florida, is an industrial technology leader that develops and manufactures solutions for both the hydraulics and electronics markets. In the hydraulics market, we are a leading manufacturer of high-performance screw-in hydraulic cartridge valves, electro-hydraulics, manifolds, and integrated package solutions for the worldwide industrial and mobile hydraulics markets operating under the brand Sun Hydraulics. In the electronics market, we are a global provider of innovative electronic control, display and instrumentation solutions for both recreational and off-highway vehicles, as well as stationary and power generation equipment; these are offered under the brands of Enovation Controls and Murphy Zero Off.

We have operated in the North American market for over 47 years. We have expanded our global footprint over the past 30 years to include operations in the United Kingdom, Germany and Korea, as well as sales offices in China and India. Enovation Controls, LLC (“Enovation Controls”), which was acquired by Sun on December 5, 2016 and is a wholly-owned subsidiary of Sun, was formed in 2009 in connection with the reorganization of Murphy Group, Inc. and EControls Group, Inc., which were founded in 1939 and 1994, respectively. Enovation Controls operates the majority of its manufacturing in Tulsa, Oklahoma with sales and engineering capabilities in San Antonio, Texas, the United Kingdom, China and India. Until its dissolution in December 2017, High Country Tek, Inc. (“HCT”), a wholly-owned subsidiary of Sun, operated in Nevada City, California as an independent designer and producer of modular, robust, reliable digital and analog electronic controller products for the fluid power industry sold under the brand of HCT. Subsequent to the Enovation Controls acquisition, the activities of HCT and Enovation Controls were closely coordinated. On December 29,

1

2017, all of the outstanding shares of HCT were transferred to Enovation Controls. Subsequently, Enovation Controls adopted a plan of liquidation and HCT was dissolved on December 30, 2017.

Until 2016, we operated primarily in the hydraulics market with a small presence in the electronics market through HCT. On December 5, 2016, we purchased the power controls and vehicle technologies businesses of Enovation Controls, retaining the legal entity and related brands. The expansion of our electronic and digital capabilities through the acquisition of Enovation Controls was a significant step towards achieving our long-term strategic vision of expanding our electro-hydraulics offerings and providing systems solutions to customers. The acquisition further diversified our business, granting us access to the new, highly specialized marine, power generation and recreational vehicles markets and customers seeking complete machine control. Enovation Controls also brought a strong talent pool with a proven track record of new product development and technical innovation, complementing our existing competencies.

We have been profitable every year since 1972 and have paid a dividend every quarter since going public in January 1997.

The Company’s executive offices are located at 1500 West University Parkway, Sarasota, Florida 34243, and our telephone number is (941) 362-1200. Our primary website is www.sunhydraulics.com.

2

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, including the documents incorporated by reference herein, contains forward-looking statements. All statements other than statements of historical facts contained in this prospectus and the documents incorporated by reference herein are forward-looking statements. Examples include, among others, statements we make regarding:

These statements involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. This prospectus and the documents incorporated by reference herein also contain estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplates,” “believes,” “estimates,” “predicts,” “potential” or “continue” or the negative of these terms or other similar expressions. The forward-looking statements in this prospectus and the documents incorporated by reference herein are only predictions. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our business, financial condition and results of operations. These forward-looking statements speak only as of the date of this prospectus and are subject to a number of risks, uncertainties and assumptions, including, among others, the following:

3

The events and circumstances reflected in our forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in the forward-looking statements. Moreover, we operate in an evolving environment. New risk factors and uncertainties may emerge from time to time, and it is not possible for management to predict all risk factors and uncertainties. Given these risks and uncertainties, you should not place undue reliance on these forward-looking statements. Except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained in this prospectus or the documents incorporated by reference herein, whether as a result of any new information, future events, changed circumstances or otherwise. For all forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995.

4

RISK FACTORS

Investment in any securities offered pursuant to this prospectus and the applicable prospectus supplement involves risks. You should carefully consider the risk factors set forth under the caption “Risk Factors” in the applicable prospectus supplement and under the caption “Risk Factors” contained in our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, and all other information contained in or incorporated by reference into this prospectus.. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities. Please also refer to the section above entitled “Forward-Looking Statements.” For more information about our periodic filings made with the SEC, see “Where You Can Find More Information.”

USE OF PROCEEDS

Unless we indicate otherwise in the applicable prospectus supplement, the net proceeds from the sale of securities will be used for general corporate purposes, which may include the repayment of outstanding indebtedness under our credit facility or the financing of potential acquisitions.

5

DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock is not complete and may not contain all the information you should consider before investing in our capital stock. This description is summarized from, and qualified in its entirety by reference to, our Amended and Restated Articles of Incorporation, as amended (the “Articles”), which have been publicly filed with the SEC. See “Where You Can Find More Information” and “Incorporation by Reference.”

The authorized capital stock of the Company consists of (i) 50,000,000 shares of Common Stock, $0.001 par value per share (“Common Stock”), and (ii) 2,000,000 shares of preferred stock, $0.001 par value per share (the “Preferred Stock”).

Common Stock

As of December 30, 2017, there were 27,077,145 shares of our Common Stock outstanding.

Holders of shares of Common Stock are entitled to one vote per share on all matters to be voted upon by the shareholders. Subject to the prior rights of the holders of Preferred Stock, if any, holders of Common Stock are entitled to receive dividends when, as and if declared by the Board of Directors from funds legally available therefor, and to share ratably in the assets of the Company legally available for distribution to the shareholders in the event of liquidation or dissolution. The Common Stock has no preemptive rights or redemption privileges. Under the Florida Business Corporation Act (the “FBCA”), directors are elected by a plurality of votes cast by holders of our Common Stock at a meeting at which a quorum is present. Under our Amended and Restated Bylaws (the “Bylaws”), if a quorum exists any other action is approved if the votes cast favoring the action exceed the votes cast opposing the action, unless our Articles or the FBCA require a greater number of affirmative votes.

The rights of holders of Common Stock are subject to the rights of holders of any Preferred Stock that we have designated or that we may designated in the future. The rights of the holders of Preferred Stock may adversely affect the rights of the holders of our Common Stock.

Transfer Agent

The transfer agent for our Common Stock is Computershare.

Preferred Stock

The Company is authorized to issue 2,000,000 shares of Preferred Stock. The Preferred Stock may be issued from time to time in one or more series, and the Board of Directors is authorized to fix the dividend rights, dividend rates, conversion or exchange rights, voting rights, rights and terms of redemption (including sinking fund provisions), redemption price or prices, the liquidation preferences and any other rights, preferences, privileges and restrictions of any series of Preferred Stock and the number of shares constituting such series and the designation thereof. The Company does not have any shares of Preferred Stock outstanding, and it has no present plans to issue any shares of Preferred Stock.

Depending upon the rights of such Preferred Stock, the issuance of Preferred Stock could have an adverse effect on holders of Common Stock by delaying or preventing a change in control of the Company, making removal of the present management of the Company more difficult or resulting in restrictions upon the payment of dividends and other distributions to the holders of Common Stock.

Director’s Liability

As authorized by the FBCA the Articles limit the liability of Directors to the Company for monetary damages. The effect of this provision in the Articles is to eliminate the rights of the Company and its

6

shareholders (through shareholders’ derivative suits on behalf of the Company) to recover monetary damages from Directors for breaches of their fiduciary duties as Directors (including breaches resulting from negligent behavior), except in certain circumstances involving wrongful acts, such as the breach of a Director’s duty of loyalty or acts or omissions which involve intentional misconduct or a knowing violation of law. Further, the Articles contain provisions to indemnify the Company’s Directors and Officers to the full extent permitted by the FBCA. These provisions do not limit or eliminate the rights of the Company or any shareholder to seek non-monetary relief such as an injunction or rescission in the event of a breach of a Director’s fiduciary duty. These provisions will not alter the liability of Directors under federal securities laws.

Certain Provisions of Florida Law

The Company is subject to several anti-takeover provisions under the FBCA that apply to a public corporation organized under the FBCA, unless the corporation has elected to opt out of those provisions in its articles of incorporation or bylaws. The Company has not elected to opt out of those provisions. The FBCA prohibits the voting of shares in a publicly-held Florida corporation that are acquired in a “control share acquisition” unless (i) the Board of Directors approved such acquisition prior to its consummation or (ii) after such acquisition, in lieu of prior approval of the Board of Directors, the holders of a majority of the corporation’s voting shares (exclusive of shares held by officers of the corporation, inside directors, or the acquiring party) approve the granting of voting rights as to the shares acquired in the control share acquisition. A “control share acquisition” is defined as an acquisition that immediately thereafter entitles the acquiring party to vote in the election of directors within each of the following ranges of voting power: (i) one-fifth or more but less than one-third of such voting power, (ii) one-third or more but less than a majority of such voting power, and (iii) more than a majority of such voting power.

The FBCA also contains an “affiliated transaction” provision that prohibits a publicly-held Florida corporation from engaging in a broad range of business combinations or other extraordinary corporate transactions with an “interested shareholder” unless (i) the transaction is approved by a majority of disinterested directors before the person becomes an interested shareholder, (ii) the corporation has not had more than 300 shareholders of record during the three years preceding the transaction, (iii) the interested shareholder has owned at least 80% of the corporation’s outstanding voting shares for at least five years, (iv) the interested shareholder is the beneficial owner of at least 90% of the voting shares (excluding shares acquired directly from the corporation in a transaction not approved by a majority of the disinterested directors), (v) consideration is paid to the holders of the corporation’s shares equal to the highest amount per share paid by the interested shareholder for the acquisition of the corporation’s shares in the last two years or fair market value, and other specified conditions are met, or (vi) the transaction is approved by the holders of two-thirds of the corporation’s voting shares other than those owned by the interested shareholder. An interested shareholder is defined as a person who together with affiliates and associates beneficially owns more than 10% of the corporation’s outstanding voting shares.

Anti-Takeover Effects of Provisions of the Company’s Articles and Bylaws

Certain provisions of the Articles and the Bylaws could have an anti-takeover effect. These provisions are intended to enhance the likelihood of continuity and stability in the composition of the Board of Directors of the Company and in the policies formulated by the Board of Directors and to discourage certain types of transactions, described below, which may involve an actual or threatened change of control of the Company. The provisions are designed to reduce the vulnerability of the Company to an unsolicited proposal for a takeover of the Company that does not contemplate the acquisition of all of its outstanding shares or an unsolicited proposal for the restructuring or sale of all or part of the Company. The provisions are also intended to discourage certain tactics that may be used in proxy fights.

7

Amended and Restated Articles of Incorporation

Classified Board of Directors

The Articles provide for the Board of Directors to be divided into three classes of Directors serving staggered three-year terms. As a result, approximately one-third of the Board of Directors will be elected each year. The classified Board of Directors provision could have the effect of discouraging a third party from making a tender offer or otherwise attempting to obtain control of the Company, even though such an attempt might be beneficial to the Company and its shareholders. In addition, the classified board provision could delay shareholders who do not agree with the policies of the Board of Directors from removing a majority of the Board for two years, unless they can show cause and obtain the requisite vote.

Special Meetings of Shareholders

The Articles provide that special meetings of shareholders of the Company may be called only by the Chairman, the President, a majority of the members of the Board of Directors or by the holders of 50% of the outstanding stock entitled to vote on an issue proposed to be considered at the special meeting. The Articles also prohibit the taking of shareholder action by written consent without a meeting if there are more than 30 shareholders of record. This provision will make it more difficult for shareholders to take action opposed by the Board of Directors.

Amendment of Certain Provisions of the Articles

The Articles generally require the affirmative vote of the holders of at least 80% of the outstanding voting stock in order to amend its provisions, including any provisions concerning (i) the classified board, (ii) the amendment of the Bylaws, (iii) the authority of shareholders to act by written consent, (iv) indemnification, (v) the liability of Directors, (vi) the calling of special meetings of the shareholders, and (vii) the supermajority voting requirements described in this paragraph. These voting requirements will make it more difficult for shareholders to make changes in the Articles which would be designed to facilitate the exercise of control over the Company. In addition, the requirement for approval by at least an 80% shareholder vote will enable the holders of a minority of the voting securities of the Company to prevent the holders of a majority or more of such securities from amending such provisions of the Articles.

Number of Directors; Removal

The Articles provide that the Board of Directors will consist of that number of Directors as shall be fixed from time to time by resolution adopted by a majority of the Directors then in office. Subject to the rights of the holders of any series of Preferred Stock then outstanding, the Articles provide that Directors of the Company may be removed only for cause and only by the affirmative vote of holders of a majority of the outstanding shares of voting stock. This provision will preclude a shareholder from removing incumbent Directors without cause and simultaneously gaining control of the Board of Directors by filling the vacancies created by such removal with its own nominees.

Amended and Restated Bylaws

The Bylaws establish an advance notice procedure for the nomination, other than by or at the direction of the Board of Directors or a committee thereof, of candidates for election as Director as well as for other shareholder proposals to be considered at shareholders’ meetings.

Notice of shareholder proposals and Director nominations must be timely given in writing to the Secretary of the Company prior to the meeting at which the matters are to be acted upon or at which the Directors are to be elected. To be timely, notice must be received at the principal executive offices of the Company not less than 120 days prior to the proxy statement relating to the prior year’s annual meeting of shareholders.

8

A shareholder’s notice to the Secretary with respect to a shareholder proposal shall set forth as to each matter the shareholder proposes to bring before the meeting (i) a brief description of the business desired to be brought before the annual meeting, (ii) the reasons for conducting such business at the meeting, (iii) the name and record address of the shareholder proposing such business, (iv) the class or series and number of shares of the Company which are owned beneficially or of record by the shareholder, (v) a description of all arrangements or understandings between the shareholder and any other person or persons (including their names) in connection with the proposal of such business by the shareholder and any material interest of the shareholder in such business, and (vi) a representation that the shareholder intends to appear in person or by proxy at the annual meeting to bring such business before the meeting.

The purpose of requiring advance notice is to afford the Board of Directors an opportunity to consider the qualifications of the proposed nominees or the merits of other shareholder proposals and, to the extent deemed necessary or desirable by the Board of Directors, to inform shareholders about those matters.

9

PLAN OF DISTRIBUTION

We may sell the securities on a delayed or continuous basis through one or more agents, underwriters or dealers, directly to one or more purchasers, through a combination of any of these methods of sale, or in any other manner, as provided in the applicable prospectus supplement. We will identify the specific plan of distribution, including any underwriters, dealers, agents or direct purchasers and their compensation in a prospectus supplement.

We may distribute the securities from time to time in one or more transactions:

In connection with the sale of the securities, underwriters may be deemed to have received 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 dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agent.

If we use an underwriter in the sale of the securities being offered by this prospectus, then we will execute an underwriting agreement with the underwriter at the time of sale and we will provide the name of any underwriter in the applicable prospectus supplement. We will describe in the applicable prospectus supplement any underwriting compensation we pay to underwriters or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers. Dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements with any underwriters, dealers and agents which may entitle them to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act, and to reimbursement for certain expenses.

If indicated in the applicable prospectus supplement, we may authorize underwriters, dealers or other persons acting as our agents to solicit offers by certain institutions or other suitable persons to purchase the securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on the date or dates stated in the prospectus supplement. We may make delayed delivery with various institutions, including commercial and savings banks, insurance companies, pension funds, investment companies and educational and charitable institutions. Delayed delivery contracts will be subject to the condition that the purchase of the securities covered by the delayed delivery contracts will not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which the purchaser is subject. The underwriters and agents will not have any responsibility with respect to the validity or performance of these contracts.

To facilitate an offering of a series of the 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 involves the sale by persons participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover the over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option. 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

10

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 may be discontinued at any time.

Certain of the underwriters, dealers or agents and their respective associates may be customers of, and/or engage in transactions with and perform services for, us in the ordinary course of business.

11

LEGAL MATTERS

The validity of the issuance of the shares of common stock offered hereby will be passed upon by our counsel, Shumaker, Loop & Kendrick, LLP, Tampa, Florida. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

Grant Thornton, LLP, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2016, and the effectiveness of our internal control over financial reporting as of December 31, 2016. The audited financial statements and management’s assessment of the effectiveness of internal control over financial reporting incorporated by reference in this prospectus and elsewhere in the registration statement have been so incorporated by reference in reliance upon the reports of Grant Thornton LLP, independent registered public accountants, upon the authority of said firm as experts in accounting and auditing.

Grant Thornton, LLP, has audited the abbreviated financial statements of the Power Controls and Vehicle Technologies Lines of Business of Enovation Controls, LLC as of December 5, 2016, and for the for the nine month period ended September 30, 2016 and the years ended December 31, 2015 and 2014 included in our Current Report on Form 8-K/A, filed with the SEC on February 17, 2017. The abbreviated financial statements incorporated by reference in this prospectus and elsewhere in the registration statement have been so incorporated by reference in reliance upon the report of Grant Thornton LLP, independent certified public accountants, upon the authority of said firm as experts in accounting and auditing.

Mayer Hoffman McCann P.C., an independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the years ended January 2, 2016 and December 27, 2014, and the effectiveness of our internal control over financial reporting as of January 2, 2016 and December 27, 2014, as set forth in their reports, which are incorporated by reference in this prospectus and elsewhere in the registration statement. The consolidated financial statements and management’s assessment of the effectiveness of internal control over financial reporting incorporated by reference in this this prospectus and elsewhere in the registration statement have been so incorporated by reference in reliance upon the reports of Mayer Hoffman McCann P.C., independent registered public accountants, upon the authority of said firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We file reports, proxy statements and other information with the SEC. Information filed with the SEC by us can be inspected and copied at the Public Reference facilities maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549. You may also obtain copies of this information by mail from the Public Reference Room of the SEC at prescribed rates. Further information on the operation of the SEC’s Public Reference Room in Washington, D.C. can be obtained by calling the SEC at 1-800-SEC-0330. The SEC also maintains a website that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. You may also access filed documents at the SEC’s website at www.sec.gov or by accessing the Investor Relations section of our website at www.sunhydraulics.com. The information on, or accessible through, our website is not part of, and is not incorporated into, this prospectus, and should not be deemed to be, a part of this prospectus.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided above. Other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement. Statements in this prospectus or any prospectus supplement about these

12

documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters.

INFORMATION INCORPORATED BY REFERENCE

The SEC’s rules allow us to “incorporate by reference” information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus modifies or replaces that statement.

We incorporate by reference our documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act if 1934, as amended (the “Exchange Act”) between the date of this prospectus and the termination of the offering of the securities described in this prospectus. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed below or filed in the future, that are not deemed “filed” with the SEC, including our Compensation Committee report and performance graph or any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus by writing or telephoning us at the following address:

SUN HYDRAULICS CORPORATION

ATTN: CORPORATE SECRETARY

1500 WEST UNIVERSITY PARKWAY

SARASOTA, FLORIDA 34243

(941) 362-1200

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus and any accompanying prospectus supplement.

13

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

The following is an estimate of the expenses (all of which are to be paid by the registrant) that we may incur in connection with the securities being registered hereby:

Item 15. Indemnification of Directors and Officers

As a corporation incorporated in the State of Florida, we are subject to the Florida Business Corporation Act, or the FBCA. Section 607.0831 of the FBCA provides that a director is not personally liable for monetary damages to the corporation or any other person for any statement, vote, decision, or failure to act regarding corporate management or policy unless (1) the director breached or failed to perform his or her duties as a director and (2) the director’s breach of, or failure to perform, those duties constitutes (a) a violation of the criminal law, unless the director had reasonable cause to believe his or her conduct was lawful or had no reasonable cause to believe his or her conduct was unlawful, (b) a transaction from which the director derived an improper personal benefit, either directly or indirectly, (c) a circumstance under which the liability provisions of Section 607.0834 are applicable, (d) in a proceeding by or in the right of the corporation to procure a judgment in its favor or by or in the right of a shareholder, conscious disregard for the best interest of the corporation, or willful misconduct, or (e) in a proceeding by or in the right of someone other than the corporation or a shareholder, recklessness or an act or omission which was committed in bad faith or with malicious purpose or in a manner exhibiting wanton and willful disregard of human rights, safety, or property. A judgment or other final adjudication against a director in any criminal proceeding for a violation of the criminal law estops that director from contesting the fact that his or her breach, or failure to perform, constitutes a violation of the criminal law; but does not estop the director from establishing that he or she had reasonable cause to believe that his or her conduct was lawful or had no reasonable cause to believe that his or her conduct was unlawful.

Under Section 607.0850(1) of the FBCA, a corporation has the power to indemnify any person who was or is a party to any proceeding (other than an action by, or in the right of the corporation), by reason of the fact that he or she is or was a director, officer, employee or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against liability incurred in connection with such proceeding, including any appeal thereof, if he or she acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful. The termination of any proceeding by judgment, order, settlement or conviction or upon a plea of nolo contendere or its equivalent shall not, of itself, create a presumption that the person did not act in good faith and in a manner which he or she reasonably believed to be in, or not opposed to, the best interests of the corporation or, with respect to any criminal action or proceeding, has reasonable cause to believe that his or her conduct was unlawful.

II-1

Under Section 607.0850(2) of the FBCA, a corporation has the power to indemnify any person, who was or is a party to any proceeding by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person is or was a director, officer, employee, or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee, or agent of another corporation, partnership, joint venture, trust, or other enterprise, against expenses and amounts paid in settlement not exceeding, in the judgment of the board of directors, the estimated expense of litigating the proceeding to conclusion, actually and reasonably incurred in connection with the defense or settlement of such proceeding, including any appeal thereof. Such indemnification shall be authorized if such person acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, except that no indemnification shall be made under this subsection in respect of any claim, issue, or matter as to which such person shall have been adjudged to be liable unless, and only to the extent that, the court in which such proceeding was brought, or any other court of competent jurisdiction, shall determine upon application that, despite the adjudication of liability but in view of all circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which such court shall deem proper.

In addition, under Section 607.0850(3) of the FBCA, to the extent that a director, officer, employee or agent of the corporation has been successful on the merits or otherwise in defense of any proceeding referred to in Sections 607.0850(1) or 607.0850(2) described above, or in defense of any claim, issue, or matter therein, he or she shall be indemnified against expenses actually and reasonably incurred by him or her in connection therewith.

Under Section 607.0850 of the FBCA, the indemnification and advancement of expenses provided pursuant to Section 607.0850 of the FBCA are not exclusive, and a corporation may make any other or further indemnification or advancement of expenses of any of its directors, officers, employees, or agents, under any bylaw, agreement, vote of shareholders or disinterested directors, or otherwise, both as to action in his or her official capacity and as to action in another capacity while holding such office. However, indemnification or advancement of expenses shall not be made to or on behalf of any director, officer, employee or agent if a judgment or other final adjudication establishes that his or her actions, or omissions to act, were material to the cause of action so adjudicated and constitute: (a) a violation of the criminal law, unless the director, officer, employee or agent had reasonable cause to believe his or her conduct was unlawful; (b) a transaction from which the director, officer, employee or agent derived an improper personal benefit; (c) in the case of a director, a circumstance under which the above liability provisions of Section 607.0834 are applicable; or (d) willful misconduct or a conscious disregard for the best interests of the corporation in a proceeding by or in the right of the corporation to procure a judgment in its favor or in a proceeding by or in the right of a shareholder. Our amended and restated articles of incorporation, as amended, provide that we shall indemnify our officers and directors to the fullest extent permitted by the current law.

Section 607.0850 also provides that a corporation shall have the power to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation against any liability asserted against the person and incurred by him or her in any such capacity or arising out of his status as such, whether or not the corporation would have the power to indemnify him against such liability under the provisions of Section 607.0850. We have secured insurance covering our directors and officers and those of our principal subsidiaries and affiliate companies against certain liabilities.

We have entered into indemnification agreements with each member of our board of directors and our executive officers. The indemnification agreements require, among other things, that we indemnify to the fullest extent permitted by law and advance to each indemnified director and executive officer all related expenses, subject to reimbursement if it is subsequently determined that indemnification is not permitted. Under the indemnification agreements, we must also indemnify and advance all expenses incurred by an indemnified director or executive officer seeking to enforce his or her rights under the indemnification agreements. Although the indemnification agreements offer substantially the same scope of coverage afforded by law, they provide greater assurance to directors and executive officers that indemnification will be available, because, as contracts, they cannot be modified unilaterally in the future by the board of directors or the shareholders to eliminate the rights they provide.

II-2

The Company carries Directors’ and Officers’ liability insurance.

Item 16. Exhibits

A list of exhibits filed with this registration statement on Form S-3 is set forth on the Exhibit Index below.

Item 17. Undertakings

(a) The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that subparagraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act to any purchaser:

(i) each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(ii) each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5) or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no

II-3

statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5) That, for the purpose of determining liability of the registrant under the Securities Act to any purchaser in the initial distribution of the securities:

The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

II-4

EXHIBIT INDEX

II-5

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Sarasota, Florida, on January 29, 2018.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Wolfgang H. Dangel and Tricia S. Fulton, and each of them, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to file and sign any and all amendments, including post-effective amendments and any registration statement for the same offering that is to be effective under Rule 462(b) of the Securities Act, to this registration statement, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-fact and agents or any of them, or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof. This power of attorney shall be governed by and construed with the laws of the State of Florida and applicable federal securities laws.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed below by the following persons on behalf of the registrant in the capacities and on the dates indicated.

II-6

II-7