UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13G
                    Under the Securities Exchange Act of 1934

                             Rubicon Technology, Inc.
                                (Name of Issuer)

                                  Common Stock
                         (Title of Class of Securities)

                                   78112T107
                                 (CUSIP Number)

                               October 31, 2011
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[X] Rule 13d-1(b)

[ ] Rule 13d-1(c)

[ ] Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.


The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).




                               CUSIP No. 78112T107



       1.    Names of Reporting Person

             Sparta Asset Management, LLC

	     I.R.S. Identification Nos. of above persons: 26-0703880

       2.    Check the Appropriate Box if a Member Of a Group

             [ ] (a)
             [ ] (b)

       3.    SEC Use Only

       4.    Citizenship or Place of Organization

             Delaware, United States

       5.    Sole Voting Power: 1,047,998
Number of
Shares           6.  Shared Voting Power: 0
Beneficially
Owned by         7.  Sole Dispositive Power:  2,337,377
Each Reporting
Person With      8.  Shared Dispositive Power: 0

       9.    Aggregate Amount Beneficially Owned by Each Reporting Person

             2,337,377

       10.   Check if the Aggregate Amount in Row (9) Excludes Certain Shares

       11.   Percent of Class Represented by Amount in Row (9)

	     10.15%

       12.   Type of Reporting Person

	     IA



Item 1. (a)  Name of Issuer: Rubicon Technology, Inc

        (b)  Address of Issuer's Principal Executive Offices:

	     900 East Green Street
             Bensenville, Illinois 60106

Item 2. (a)  Name of Person Filing:

             Sparta Asset Management, LLC

        (b)  Address of Principal Business Office, or, if None, Residence:

	     One O'Hare Centre
	     6250 N. River Road, Suite 1000
	     Rosemont, IL  60018
	     United States

        (c)  Citizenship:
             Please see Item 4 on each cover sheet for each Reporting Person.

        (d)  Title of Class of Securities
             Common Stock

        (e)  CUSIP Number: 78112T107

Item 3.  Sparta Asset Management, LLC is an investment adviser in
	 accordance with ss.240.13d-1(b)(1)(ii)(E).

Item 4.  Ownership

         Please see Items 5-9 and 11 on each cover sheet for each
	 Reporting Person.

Item 5.  Ownership of Five Percent or Less of a Class

         Not Applicable

Item 6.  Ownership of More than Five Percent on Behalf of Another Person

	 Not Applicable




Item 7.  Identification and Classification of the Subsidiary Which Acquired the
         Security Being Reported on By the Parent Holding Company

         Not Applicable

Item 8.  Identification and Classification of Members of the Group

         Not Applicable

Item 9.  Notice of Dissolution of Group

         Not Applicable

Item 10. Certification

By signing below I certify that, to the best of my knowledge and belief, the
securities referred to above were acquired and are held in the ordinary
course of business and were not acquired and are not held for the purpose of
or with the effect of changing or influencing the control of the issuer of the
securities and were not acquired and are not held in connection with or as a
participant in any transaction having that purpose or effect.





                               SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.

Date:  November 14, 2011
                                       Sparta Asset Management, LLC

                                       By: /s/ Ryan Carr
                                       --------------------------
                                       Name:  Ryan Carr
                                       Title: Chief Investment Officer
					      Managing Partner