SECURITIES AND EXCHANGE COMMISSION
		     	     Washington, D.C. 20549

			  	  SCHEDULE 13G
		       	      Rule 13d-1 and 13d-2
	    	    Under the Securities Exchange Act of 1934


		     	        Matrix Service Co.
		       		 (Name of Issuer)

			  	    Common Stock
		 	  (Title of Class of Securities)
	
			   	     576853105
			          (CUSIP Number)

			  	    12/28/2005
             (Date of Event which Requires Filing of this Statement)

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

| | Rule 13d-1 (b)
|X| 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 disclosures provided in a prior cover page.

The information required on 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).



 (1) Names and I.R.S. Identification Nos.(entities only) of reporting persons.
 
    Caxton International Limited

 (2) Check the appropriate box if a member of a group (see instructions)  (a)|_|
                                                                          (b)|_|

 (3) SEC use only.

 (4) Citizenship or place of organization.
    British Virgin Islands

Number of shares beneficially owned by each reporting person with:

 (5) Sole voting power:
    0

 (6) Shared voting power:
    738,251

 (7) Sole dispositive power:
    0

 (8) Shared dispositive power:
    738,251

 (9) Aggregate amount beneficially owned by each reporting person.
    738,251

 (10) Check if the aggregate amount in Row (9) excludes certain shares	|_|
    (see instructions).

 (11) Percent of class represented by amount in Row 9.
     3.5%

 (12) Type of reporting person (see instructions).
     CO


 (1) Names and I.R.S. Identification Nos.(entities only) of reporting persons.

     GDK, Inc.
     
 (2) Check the appropriate box if a member of a group (see instructions)  (a)|_|
                                                                    	  (b)|_|

 (3) SEC use only.

 (4) Citizenship or place of organization.
    British Virgin Islands

Number of shares beneficially owned by each reporting person with:
 (5) Sole voting power:
    0

 (6) Shared voting power:
    254,285

 (7) Sole dispositive power:
    0

 (8) Shared dispositive power:
    254,285

 (9) Aggregate amount beneficially owned by each reporting person.
    254,285

 (10)Check if the aggregate amount in Row (9) excludes certain shares	|_|
    (see instructions).

 (11)Percent of class represented by amount in Row 9.
    1.2%

 (12)Type of reporting person (see instructions).
    BD

 (1) Names and I.R.S. Identification Nos.(entities only) of reporting persons.

     Caxton Associates, L.L.C.
     22-3430173

 (2) Check the appropriate box if a member of a group (see instructions)  (a)|_|
                                                                    	  (b)|_|

 (3) SEC use only.

 (4) Citizenship or place of organization.
    Delaware

    Number of shares beneficially owned by each reporting person with:
 (5) Sole voting power:
    0

 (6) Shared voting power:
    992,536

 (7) Sole dispositive power:
    0

 (8) Shared dispositive power:
    992,536

 (9) Aggregate amount beneficially owned by each reporting person.
    992,536

 (10)Check if the aggregate amount in Row (9) excludes certain shares	|_|
    (see instructions).

 (11)Percent of class represented by amount in Row 9.
    4.7%

 (12)Type of reporting person (see instructions).
    IA

 (1) Names and I.R.S. Identification Nos.(entities only) of reporting persons.
    Kovner, Bruce

 (2) Check the appropriate box if a member of a group (see instructions)  (a)|_|
                                                                          (b)|_|

 (3) SEC use only.

 (4) Citizenship or place of organization.
    United States

Number of shares beneficially owned by each reporting person with:
 (5) Sole voting power:
    0

 (6) Shared voting power:
    992,536

 (7) Sole dispositive power:
    0

 (8) Shared dispositive power:
    992,536

 (9) Aggregate amount beneficially owned by each reporting person.
    992,536

 (10) Check if the aggregate amount in Row (9) excludes certain shares	|_|
    (see instructions).

 (11) Percent of class represented by amount in Row 9.
     4.7%

 (12) Type of reporting person (see instructions).
     IN

 (1) Names and I.R.S. Identification Nos.(entities only) of reporting persons.

     Ross Taylor

 (2) Check the appropriate box if a member of a group (see instructions)  (a)|_|
                                                                    	  (b)|x|

 (3) SEC use only.

 (4) Citizenship or place of organization.
    United States

    Number of shares beneficially owned by each reporting person with:
 (5) Sole voting power:
    1,200

 (6) Shared voting power:
    0

 (7) Sole dispositive power:
    1,200

 (8) Shared dispositive power:
    0

 (9) Aggregate amount beneficially owned by each reporting person.
    1,200

 (10)Check if the aggregate amount in Row (9) excludes certain shares	|_|
    (see instructions).

 (11)Percent of class represented by amount in Row 9.
    0.01%

 (12)Type of reporting person (see instructions).
    IN

Item 1(a). Name of Issuer:
           Matrix Service Co.

Item 1(b). Address of Issuer's Principal Executive Offices:
	   10701 East Ute Street
	   Tulsa, Oklahoma 74116-1517

Item 2(a). Name of Person Filing:
(i)   Caxton International Limited ("Caxton International")
(ii)  GDK, Inc. ("GDK")
(iii) Caxton Associates, L.L.C. ("Caxton Associates").  Caxton 
      Associates is the trading advisor to Caxton International 
      and GDK (the "Caxton Accounts") and as such, has voting and 
      dispositive power with respect to the investments of the 
      Caxton Accounts.
(iv)  Mr. Bruce S. Kovner.  Mr. Kovner is the Chairman of Caxton
      Associates and the sole shareholder of Caxton Corporation, 
      the manager and majority owner of Caxton Associates. As a 
      result of the foregoing, Mr. Kovner may be deemed 
      beneficially to own the securities of the Issuer owned 
      by the Caxton Accounts.
(v)   Mr. Ross Taylor.  Mr. Taylor is a portfolio manager for
      Caxton Associates and may be deemed to participate in the
      voting and exercise of discretion with respect to certain 
      securities for certain of Caxton Associates' investment advisory
      clients.

Item 2(b). Address or Principal Business Office or, If None, Residence:
(i)   The address of Caxton International is c/o Prime Management 
      Limited, Mechanics Building, 12 Church Street, Hamilton HM11, 
      Bermuda.
(ii)  The address of GDK is c/o Prime Management Limited, 
      Mechanics Building, 12 Church Street, Hamilton HM11, 
      Bermuda.
(iii) The address of Caxton Associates is Princeton Plaza, Building 2,
      731 Alexander Road, Princeton, NJ 08540.
(iv)  The business address of Mr. Kovner is 500 Park Avenue, 
      New York, NY  10022.
(v)   The business address of Mr. Taylor is 500 Park Avenue, 
      New York, NY  10022.

Item 2(c). Citizenship:
(i)   Caxton International is a British Virgin Islands Corporation.
(ii)  GDK is a British Virgin Islands corporation.
(iii) Caxton Associates is a Delaware limited liability company.
(iv)  Mr. Kovner is a United States citizen.
(v)   Mr. Taylor is a United States citizen.

Item 2(d). Title of Class of Securities:
           Common Stock

Item 2(e). CUSIP No.:
           576853105

Item 3. If This Statement is Filed Pursuant to Rule 13d-1(b), or 13d-2(b) or
        (c), Check Whether the Person Filing is a:
           Not Applicable

If this statement is filed pursuant to Rule 13d-1(c), check this box. |X|
 
Item 4. Ownership

(a) Amount beneficially owned as of the close of business January 6, 2006:
(i)   The amount of shares of Common Stock beneficially owned by 
      Caxton International is 738,251.
(ii)  The amount of shares of Common Stock beneficially owned by 
      GDK is 254,285.
(iii) The amount of shares of Common Stock considered to be 
      beneficially owned by Caxton Associates by reason of its 
      voting and dispositive powers is 992,536.  
(iv)  Mr. Kovner, by reason of being Chairman of Caxton Associates
      and the sole shareholder of Caxton Corporation, the manager
      and majority owner of Caxton Associates, may also be deemed to 
      beneficially own such shares.
(v)   The amount of shares of Common Stock beneficially owned by 
      Mr. Taylor is 1,200 shares.  The 1,200 shares of Common Stock 
      reported herein as beneficially owned by Mr. Taylor are owned 
      directly by Mr. Taylor.

(b) Percent of class:

(All percentages herein are based on 20,726,393 shares of Common
Stock reported to be outstanding as of October 10,2005, as reflected
in the Form 8K filed by the company on October 13, 2005.)

(i)   Caxton International beneficially owns 3.5% of the Class
      of Common Stock.
(ii)  GDK beneficially 1.2% owns of the Class of Common Stock.
(iii) Caxton Associates is deemed to beneficially own 4.7%
      of the class of Common Stock.
(iv)  Mr. Kovner is deemed to beneficially own 4.7% of the Class 
      of Common Stock.
(v)   Mr. Taylor beneficially owns 0.01% of the Class of Common Stock.
 
(c) Number of shares as to which Caxton International has:
	(i)    Sole power to vote or to direct the vote:  0
	(ii)   Shared power to vote or to direct the vote:  738,251
	(iii)  Sole power to dispose or to direct the disposition:  0 
	(iv)   Shared power to dispose or to direct the disposition 
       	     of:  738,251

     Number of shares as to which GDK has:
	(i)    Sole power to vote or to direct the vote:  0
	(ii)   Shared power to vote or to direct the vote:  254,285
	(iii)  Sole power to dispose or to direct the disposition:  0 
	(iv)   Shared power to dispose or to direct the disposition 
               of:  254,285
	
     Number of shares as to which Caxton Associates has:
	(i)    Sole power to vote or to direct the vote: 0
	(ii)   Shared power to vote or to direct the vote:  992,536
	(iii)  Sole power to dispose or to direct the disposition of:  0
	(iv)   Shared power to dispose or to direct the disposition 
             of:  992,536

     Number of shares as to which Mr. Kovner has:
	(i)    Sole power to vote or to direct the vote: 0 
	(ii)   Shared power to vote or to direct the vote:  992,536
	(iii)  Sole power to dispose or to direct the disposition of:   0
	(iv)   Shared power to dispose or to direct the disposition 
             of:  992,536

     Number of shares as to which Mr. Taylor has:
	(i)    Sole power to vote or to direct the vote: 1,200 
	(ii)   Shared power to vote or to direct the vote: 0
	(iii)  Sole power to dispose or to direct the disposition of: 1,200
	(iv)   Shared power to dispose or to direct the disposition 
               of:  0


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

If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more
than five percent of the class of securities, check the following [x].

Item 6. Ownership of More than 5 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 or Control
        Person.

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. Certifications

By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above 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.

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.

					Caxton International Limited

Date: 1/9/2006				/s/ Joseph Kelly
					Name: Joseph Kelly
					Title: Vice President and Treasurer


Date: 1/9/2006	 			/s/ Maxwell Quin
					Name: Maxwell Quin
					Title: Vice President and Secretary

					GDK, Inc.

Date: 1/9/2006				/s/ Joseph Kelly
					Name: Joseph Kelly
					Title: Vice President and Treasurer


Date: 1/9/2006	 			/s/ Maxwell Quin
					Name: Maxwell Quin
					Title: Vice President and Secretary

					Caxton Associates, L.L.C.

Date: 1/9/2006	 			/s/ Scott B. Bernstein
					Name: Scott B. Bernstein
					Title: Secretary

Date: 1/9/2006				/s/ Bruce S. Kovner
					Name: Bruce S. Kovner
					Title: signed by Scott B. Bernstein
					       as Attorney-in-Fact

Date: 1/9/2006				/s/ Ross Taylor
					Ross Taylor


The original statement shall be signed by each person on whose behalf the
statement is filed or his authorized representative. If the statement is signed
on behalf of a person by his authorized representative other than an executive
officer or general partner of the filing person, evidence of the
representative's authority to sign on behalf of such person shall be filed with
the statement, provided, however, that a power of attorney for this purpose
which is already on file with the Commission may be incorporated by reference.
The name and any title of each person who signs the statement shall be typed or
printed beneath his signature.

ATTENTION: Intentional misstatements or omissions of fact constitute Federal
criminal violations (see 18 U.S.C. 1001). (Secs. 3(b), 13(d)(1), 13(d)(2),
13(d)(5), 13(d)(6), 13(g)(1), 13(g)(2), 13(g)(5), 23, 48 Stat. 882, 894, 901;
sec. 203(a), 49 Stat. 704; sec. 8, 49 Stat. 1379; sec. 10, 78 Stat. 88a; sec.
2, 82 Stat. 454; secs. 1, 2, 84 Stat. 1497; secs. 3, 10, 18, 89 Stat. 97, 119,
155; secs. 202, 203, 91 Stat. 1494, 1498, 1499; (15 U.S.C. 78c(b), 78m(d)(1),
78m(d)(2), 78m(d)(5), 78m(d)(6), 78m(g)(1), 78m(g)(2), 78m(g)(5), 78w)) [43 FR
18499, Apr. 28, 1978, as amended at 43 FR 55756, Nov. 29, 1978; 44 FR 2148,
Jan. 9, 1979; 44 FR 11751, Mar. 2, 1979; 61 FR 49959, Sept. 24, 1996; 62 FR
35340, July 1, 1997; 63 FR 2867, Jan. 16, 1998; 63 FR 15287, Mar. 31, 1998]


Certification


The undersigned hereby certifies that the shares of Matrix Service 
Co. purchased on behalf of Caxton International Limited and GDK, Inc.
were not acquired and are not being held for the purpose of or with the effect 
of changing or influencing the control of the issuer of such securities
and were not acquired and are not held in connection with or as a 
participant in any transaction having that purpose or effect.

				 
					
Date: 1/9/2006				/s/ Andy Waldman
					    Andy Waldman

					/s/ Ross Taylor
					    Ross Taylor	






                         JOINT ACQUISITION STATEMENT
                        PURSUANT TO RULE 13d-1(k) (1)

The undersigned acknowledge and agree that the foregoing statement on Schedule
13G is filed on behalf of each of the undersigned and that all subsequent
amendments to this statement on Schedule 13G shall be filed on behalf of each
of the undersigned without the necessity of filing additional joint acquisition
statements.  The undersigned acknowledge that each shall be responsible for the
timely filing of such amendments, and for the completeness and accuracy of the 
information concerning him or it contained therein, but shall not be 
responsible for the completeness and accuracy of the information concerning 
the other, except to the extent that he or it knows or has reason to believe 
that such information is inaccurate.

Dated: 1/9/2006

					Caxton International Limited

					/s/ Joseph Kelly
					Name: Joseph Kelly
					Title: Vice President and Treasurer

				  	/s/ Maxwell Quin
					Name: Maxwell Quin
					Title: Vice President and Secretary

					GDK, Inc.

					/s/ Joseph Kelly
					Name: Joseph Kelly
					Title: Vice President and Treasurer

				  	/s/ Maxwell Quin
					Name: Maxwell Quin
					Title: Vice President and Secretary

							
					Caxton Associates, L.L.C.

				 	/s/ Scott B. Bernstein
					Name: Scott B. Bernstein
					Title: Secretary

				  	/s/ Bruce S. Kovner
					Name: Bruce S. Kovner
					Title: signed by Scott B. Bernstein
       					       as Attorney-in-Fact

					/s/ Ross Taylor
					Ross Taylor