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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0000820478-10-000002.txt : 20100114
<SEC-HEADER>0000820478-10-000002.hdr.sgml : 20100114
<ACCEPTANCE-DATETIME>20100114152342
ACCESSION NUMBER:		0000820478-10-000002
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20100114
DATE AS OF CHANGE:		20100114

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CECO ENVIRONMENTAL CORP
		CENTRAL INDEX KEY:			0000003197
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL & COMMERCIAL FANS & BLOWERS & AIR PURIFYING EQUIP [3564]
		IRS NUMBER:				132566064
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-19763
		FILM NUMBER:		10527561

	BUSINESS ADDRESS:	
		STREET 1:		3120 FORRER STREET
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45209
		BUSINESS PHONE:		4165936543

	MAIL ADDRESS:	
		STREET 1:		505 UNIVERSITY AVENUE
		STREET 2:		SUITE 1400
		CITY:			TORONTO
		STATE:			A6
		ZIP:			M5G 1X3

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	API ENTERPRISES INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALARM PRODUCTS INTERNATIONAL INC
		DATE OF NAME CHANGE:	19851210

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STRS OHIO
		CENTRAL INDEX KEY:			0000820478
		IRS NUMBER:				311312155
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			0630

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		275 EAST BROAD STREET
		CITY:			COLUMBUS
		STATE:			OH
		ZIP:			43215-3771
		BUSINESS PHONE:		6142272848

	MAIL ADDRESS:	
		STREET 1:		275 E BROAD ST
		CITY:			COLUMBUS
		STATE:			OH
		ZIP:			43215

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	STATE TEACHERS RETIREMENT SYSTEM OF OHIO
		DATE OF NAME CHANGE:	19970331
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>cece2010011113ga.htm
<DESCRIPTION>13GA JAN 2010
<TEXT>
<HTML><BODY>
<P style="LINE-HEIGHT: 100%" align=center>&nbsp;</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center><B>UNITED
STATES</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center><B>SECURITIES AND
EXCHANGE COMMISSION</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>Washington, D.C.
20549</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>&nbsp;</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center><B>SCHEDULE
13G/A</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center><B>Under the
Securities Exchange Act of 1934</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>&nbsp;</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center><B>CECO ENVIRONMENTAL CORP
(CECE)</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>(Name of
Issuer)</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>&nbsp;</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%"
align=center><B>COM</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>(Title of Class of
Securities)</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%"
align=center><B>&nbsp;</B>&nbsp;</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center><B>125141101</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>(CUSIP Number)</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%"
align=center><B>&nbsp;</B>&nbsp;</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%"
align=center><B>12/31/2009</B></P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%" align=center>(Date of Event
Which Requires Filing of this Statement)</P>
<P style="MARGIN-TOP: -15px; LINE-HEIGHT: 100%"
align=center><B>&nbsp;</B>&nbsp;</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:</P>
<P>[*] Rule 13d-1(b)</P>
<P>[ ] Rule 13d-1(c)</P>
<P>[ ] Rule 13d-1(d)</P>
<P></P>
<P>* 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.</P>
<P></P>
<P>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).</P>
<P></P>
<P style="MARGIN-TOP: -20px"></P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>1) Names of Reporting Persons, IRS Identification Nos. of Above Persons:</P>
<P>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OTR - Nominee Name for The State
Teachers Retirement Board of Ohio, 31-1312155     </P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>2) Check the appropriate box if a member of a group*&nbsp;&nbsp;(a)
[_]&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) [_]</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>3) SEC Use Only</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>4) Citizenship or Place of Organization</P>
<P>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Columbus, Ohio</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Number of Shares Beneficially Owned by Each Reporting Person With</P>
<P>5) Sole Voting Power&nbsp;&nbsp;&nbsp; 850,000</P>
<P>6) Shared Voting Power&nbsp;&nbsp;&nbsp; 0</P>
<P>7) Sole Dispositive Power&nbsp;&nbsp;&nbsp; 850,000</P>
<P>8) Shared Dispositive Power&nbsp;&nbsp;&nbsp; 0</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>9) Aggregate Amount Beneficially Owned by Each Reporting
Person&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 850,000</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>10) Check if the Aggregate Amount in Row (9) Excludes Certain
Shares*&nbsp;&nbsp;[_]</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>11) Percent of Class Represented by Amount in Row
(9)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 5.95%</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>12) Type of Reporting Person*&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; EP</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>SCHEDULE 13G</P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 1</P>
<BLOCKQUOTE>
  <P>(a) Name of Issuer</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">This Statement on Schedule 13G relates to the
    shares of Instrument</P>
    <P style="MARGIN-TOP: -15px">CECO ENVIRONMENTAL CORP</P></BLOCKQUOTE>
  <P>(b) Address of Issuer's Principal Executive Offices:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">3120 Forrer Street                                </P>
    <P style="MARGIN-TOP: -15px"></P>
    <P style="MARGIN-TOP: -15px">Cincinnati                                        , OH
    45209     </P></BLOCKQUOTE></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 2&nbsp;&nbsp;&nbsp;&nbsp;</P>
<BLOCKQUOTE>
  <P>(a) Name of Person Filing:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">This Statement is filed by</P>
    <P style="MARGIN-TOP: -15px">OTR - Nominee Name for The State Teachers
    Retirement Board of Ohio</P></BLOCKQUOTE>
  <P>(b) Address of Principal Business Office:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">The business address of OTR - Nominee Name for
    The State Teachers Retirement Board of Ohio is</P>
    <P style="MARGIN-TOP: -15px">275 East Broad Street                             </P>
    <P style="MARGIN-TOP: -15px">Columbus, Ohio  43215                             </P></BLOCKQUOTE>
  <P>(c) Citizenship:&nbsp;&nbsp;&nbsp;&nbsp; Not Applicable</P>
  <P>(d) Title of Class of Securities:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">The securities are shares of
  COM.</P></BLOCKQUOTE>
  <P>(e) CUSIP No.:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">The CUSIP Number for the investment is
    125141101.</P></BLOCKQUOTE></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Type of Person
Filing:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</P>
<BLOCKQUOTE>
  <P>(a) [ ] Broker or dealer registered under section 15 of the Act (15 U.S.C.
  78o)</P>
  <P>(b) [ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).</P>
  <P>(c) [ ] Insurance company as defined in section 3(a)(19) of the Act (15
  U.S.C. 78c).</P>
  <P>(d) [ ] Investment company registered under section 8 of the Investment
  Company Act of 1940 (15 U.S.C. 90a-8)</P>
  <P>(e) [ ] An investment adviser in accordance with
240.13d-1(b)(1)(ii)(E);</P>
  <P>(f) [*] An employee benefit plan or endowment fund in accordance with
  240.13d-1(b)(1)(ii)(F);</P>
  <BLOCKQUOTE>
    <P>State Teachers Retirement System of Ohio is an employee benefit plan
    established for teachers of the public schools of Ohio to provide retirement
    allowances and other benefits under the terms of Chapter 3307 of the Ohio
    Revised Code.</P></BLOCKQUOTE>
  <P>(g) [ ] A parent holding company or control person in accordance with
  240.13d-1(b)(1)(ii)(G);</P>
  <P>(h) [ ] A savings association as defined in Section 3(b) of the Federal
  Deposit Insurance Act (12 U.S.C. 1813);</P>
  <P>(i) [ ] A church plan that is excluded from the definition of an investment
  company under Section 3(c)(14) of the Investment Company Act of 1940 (15
  U.S.C. 80a-3)</P></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;OWNERSHIP</P>
<BLOCKQUOTE>
  <P>(a) Amount Beneficially Owned:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">STRS owns 850,000 shares of
    CECO ENVIRONMENTAL CORP</P></BLOCKQUOTE>
  <P>(b) Percent of Class:</P>
  <BLOCKQUOTE>
    <P style="MARGIN-TOP: -15px">STRS believes that there are presently
    14,289,000 outstanding shares of CECO ENVIRONMENTAL CORP; therefore, STRS'
    ownership of 850,000 shares of CECO ENVIRONMENTAL CORP stock is 5.95% of
    this class.</P></BLOCKQUOTE>
  <P>(c) Number of Shares As To Which Such Person Has Power:</P>
  <BLOCKQUOTE>
    <P>(i) Sole power to vote or to direct the vote&nbsp;&nbsp;&nbsp;
    850,000</P>
    <P>(ii) Shared power to vote or to direct the vote&nbsp;&nbsp;&nbsp; 0</P>
    <P>(iii) Sole power to dispose or to direct the disposition of
    &nbsp;&nbsp;&nbsp; 850,000</P>
    <P>(iv) Shared power to dispose or to direct the disposition of 850,000
    shares of CECO ENVIRONMENTAL CORP stock.</P></BLOCKQUOTE></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OWNERSHIP OF FIVE PERCENT OR
LESS OF A CLASS.
<BLOCKQUOTE>
  <P>If this statements 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 (5) percent of the class of securities, check the following
  [ ].</P></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 6&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; OWNERSHIP OF MORE THAN FIVE
PERCENT ON BEHALF OF ANOTHER PERSON</P>
<BLOCKQUOTE>
  <P>Not Applicable</P></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 7&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; IDENTIFICATION AND
CLASSIFICATION OF SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY
THE PARENT HOLDING COMPANY.</P>
<BLOCKQUOTE>
  <P>Not Applicable</P></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 8&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; IDENTIFICATION AND
CLASSIFICATION OF MEMBERS OF THE GROUP</P>
<BLOCKQUOTE>
  <P>Not Applicable</P></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 9&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; NOTICE OF DISSOLUTION OF
GROUP</P>
<BLOCKQUOTE>
  <P>Not Applicable</P></BLOCKQUOTE>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>Item 10&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; CERTIFICATION</P>
<P>By signing below I certify that, to the best of my knowledge and belief, the
securities referred to above were acquired in the ordinary course of business
and were not acquired for the purpose of, and do not have the effect of,
changing or influencing the control of the issuer of such securities, and were
not acquired in connection with, or as a participant in, any transaction having
such purposes or effect. </P>
<P
style="MARGIN-TOP: -20px">&nbsp;________________________________________________________________________________</P>
<P>SIGNATURE</P>
<P>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. &nbsp;</P>
<P>DATED:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;01/11/2010</P>
<P>&nbsp;</P>
<P style="MARGIN-TOP: -20px">OTR - Nominee Name for The State Teachers
Retirement Board of Ohio</P>
<P style="MARGIN-TOP: -20px">275 East Broad Street                             </P>
<P style="MARGIN-TOP: -20px">Columbus, Ohio  43215                             </P>
<P style="MARGIN-TOP: -20px">STEPHEN A. MITCHELL </P>
<P style="MARGIN-TOP: -20px">/s/Stephen A. Mitchell                               </P>
<P>...........................................</P>
<P style="MARGIN-TOP: -20px">Stephen A. Mitchell                               </P>
<P style="MARGIN-TOP: -20px">Deputy Executive Director, Investments            </P>
<P style="MARGIN-TOP: -20px">614-227-4003</P>

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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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