SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
SCHEDULE 13G
(Rule 13d-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
TO RULES 13d-1(b)(c), AND (d) AND AMENDMENTS THERETO FILED
PURSUANT TO RULE 13d-2(b)
(Amendment No.____________)(1)
Matrix Service Co.
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(Name of Issuer)
Ordinary
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(Title of Class of Securities)
576853105
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(CUSIP Number)
December 31, 2005
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(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)
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(1) 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 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. 576853105 13G Page 1 of 6 Pages
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1. NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Driehaus Capital Management LLC 20-3634295
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2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [_]
(b) [_]
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3. SEC USE ONLY
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4. CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware, U.S.A.
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NUMBER OF 5. SOLE VOTING POWER
SHARES 0
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BENEFICIALLY 6. SHARED VOTING POWER
OWNED BY 688,972
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EACH 7. SOLE DISPOSITIVE POWER
REPORTING 0
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PERSON 8. SHARED DISPOSITIVE POWER
WITH 1,100,563
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,100,563
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[-]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.6%
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12. TYPE OF REPORTING PERSON*
Investment Adviser (IA)
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
CUSIP No. 576853105 13G Page 2 of 6 Pages
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1. NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Richard H. Driehaus
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2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [_]
(b) [_]
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3. SEC USE ONLY
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4. CITIZENSHIP OR PLACE OF ORGANIZATION
U.S.A.
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NUMBER OF 5. SOLE VOTING POWER
SHARES 97,605
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BENEFICIALLY 6. SHARED VOTING POWER
OWNED BY 688,972
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EACH 7. SOLE DISPOSITIVE POWER
REPORTING 97,605
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PERSON 8. SHARED DISPOSITIVE POWER
WITH 1,100,563
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9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,198,168
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10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
[-]
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11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
6.0%
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12. TYPE OF REPORTING PERSON*
Individual (IN) and Control Person (HC)
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
CUSIP No. 576853105 13G Page 3 of 6 Pages
Item 1(a). Name of Issuer:
Matrix Service Co.
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Item 1(b). Address of Issuer's Principal Executive Offices:
10701 E. Ute St.
Tulsa, Oklahoma 74116-1517
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Item 2(a). Name of Person Filing:
(i) Driehaus Capital Management LLC
(ii) Richard H. Driehaus
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Item 2(b). Address of Principal Business Office, or if None, Residence:
(i) 25 East Erie Street; Chicago, Illinois 60611
(ii) 1336 Beltjen Rd.; The Tunick Bldg., St. Thomas, USVI 00802
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Item 2(c). Citizenship:
(i) Delaware LLC, U.S.A.
(ii) U.S.A.
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Item 2(d). Title of Class of Securities:
Ordinary
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Item 2(e). CUSIP Number:
576853105
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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:
(a) [_] Broker or dealer registered under Section 15 of the Exchange
Act.
(b) [_] Bank as defined in Section 3(a)(6) of the Exchange Act.
(c) [_] Insurance company as defined in Section 3(a)(19) of the
Exchange Act.
(d) [_] Investment company registered under Section 8 of the
Investment Company Act.
(e) (i) [X] An investment adviser in accordance with Rule
13d-1(b)(1)(ii)(E);
(f) [_] An employee benefit plan or endowment fund in accordance with
Rule 13d-1(b)(1)(ii)(F);
(g) (ii) [X] A parent holding company or control person in accordance with
Rule 13d-1(b)(1)(ii)(G);
(h) [_] A savings association as defined in Section 3(b) of the
Federal Deposit Insurance Act;
(i) [_] A church plan that is excluded from the definition of an
investment company under Section 3(c)(14) of the Investment
Company Act;
(j) [_] Group, in accordance with Rule 13d-1(b)(1)(ii)(J).
CUSIP No. 576853105 13G Page 4 of 6 Pages
Item 4. Ownership.
Provide the following information regarding the aggregate number and
percentage of the class of securities of the issuer identified in Item 1.
(a) Amount beneficially owned:
(i) 1,100,563
(ii) 1,198,168
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(b) Percent of class:
(i) 5.6%
(ii) 6.0%
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(c) Number of shares as to which Driehaus Capital Management LLC has:
(i) Sole power to vote or to direct the vote 0,
(ii) Shared power to vote or to direct the vote 688,972,
(iii) Sole power to dispose or to direct the disposition of 0,
(iv) Shared power to dispose or to direct the disposition of 1,100,563
Number of shares as to which Richard H. Driehaus has:
(i) Sole power to vote or to direct the vote 97,605,
(ii) Shared power to vote or to direct the vote 688,972,
(iii) Sole power to dispose or to direct the disposition of 97,605,
(iv) Shared power to dispose or to direct the disposition of 1,100,563
Item 5. Ownership of Five 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 [ ].
Not applicable
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Item 6. Ownership of More Than Five Percent on Behalf of Another Person.
The shares reported herein by Driehaus Capital Management LLC ("DCM"),
are held by numerous clients on a fully discretionary basis in
accounts managed by DCM. Securities held in these clients' accounts
are included in this report to reflect the fact that DCM may have
voting power and dispositive power. To the best of DCM's knowledge,
none of the clients whose securities are included in this report have
the right to receive dividends or direct the proceeds from the sale
of interests relating to more than 5% of the class.
Richard H. Driehaus, a control person of DCM, is deemed to share
beneficial ownership of the shares held in DCM client accounts and has
included those shares in this report. Shares reported herein by
Mr. Driehaus are also held in account(s) held by him directly,
over which Mr. Driehaus has sole voting and dispositive power.
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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
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Item 8. Identification and Classification of Members of the Group.
Not applicable
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Item 9. Notice of Dissolution of Group.
Not applicable
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Item 10. Certifications.
(a) The following certification shall be included if the statement is
filed pursuant to Rule 13d-1(b):
"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 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 such purpose or effect."
CUSIP No. 576853105 13G Page 5 of 6 Pages
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.
DRIEHAUS CAPITAL MANAGEMENT LLC
February 14, 2006
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(Date)
/s/ Mary H. Weiss
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(Signature)
Mary H. Weiss/Senior Vice President
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(Name/Title)
RICHARD H. DRIEHAUS
February 14, 2006
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(Date)
/s/ Richard H. Driehaus
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(Signature)
CUSIP No. 576853105 13G Page 6 of 6 Pages
Note. Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for other parties
for whom copies are to be sent.
Attention. Intentional misstatements or omissions of fact constitute federal
criminal violations (see 18 U.S.C. 1001).