SEC Form 5

FORM 5		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0362 Estimated average burden hours per response: 1.0
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
	Form 3 Holdings Reported.
X	Form 4 Transactions Reported.

1. Name and Address of Reporting Person* DEZWIREK PHILLIP (Last) (First) (Middle) 2300 YONGE STREET, SUITE 1710 (Street) TORONTO A6 M4P 1E4 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol CECO ENVIRONMENTAL CORP [ CECE ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner X Officer (give title below) Other (specify below) Chairman
	3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year) 12/31/2010
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)	4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned at end of Issuer's Fiscal Year (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
				Amount	(A) or (D)	Price
Common Stock	03/03/2010		P4	2,500	A	$3.52(1)	1,951,042	I	By Icarus Investment Corp.(25)
Common Stock	03/30/2010		P4	36,000	A	$3.58(2)	1,987,042	I	By Icarus Investment Corp.(25)
Common Stock	05/13/2010		P4	2,000	A	$5.25(3)	1,989,042	I	By Icarus Investment Corp.(25)
Common Stock	05/18/2010		P4	13,878	A	$4.81(4)	2,002,920	I	By Icarus Investment Corp.(25)
Common Stock	05/25/2010		P4	1,000	A	$4.84	2,003,920	I	By Icarus Investment Corp.(25)
Common Stock	05/26/2010		P4	30,300	A	$5.05(5)	2,034,220	I	By Icarus Investment Corp.(25)
Common Stock	05/28/2010		P4	2,000	A	$5.02(6)	2,036,220	I	By Icarus Investment Corp.(25)
Common Stock	06/09/2010		P4	5,200	A	$4.66(7)	2,041,420	I	By Icarus Investment Corp.(25)
Common Stock	06/17/2010		P4	2,100	A	$5.05(8)	2,043,520	I	By Icarus Investment Corp.(25)
Common Stock	06/18/2010		P4	1,000	A	$5.06	2,044,520	I	By Icarus Investment Corp.(25)
Common Stock	06/21/2010		P4	1,000	A	$5.08	2,045,520	I	By Icarus Investment Corp.(25)
Common Stock	06/22/2010		P4	8,500	A	$4.9(9)	2,054,020	I	By Icarus Investment Corp.(25)
Common Stock	06/23/2010		P4	18,535	A	$4.73(10)	2,072,555	I	By Icarus Investment Corp.(25)
Common Stock	06/24/2010		P4	4,151	A	$4.76(11)	2,076,706	I	By Icarus Investment Corp.(25)
Common Stock	06/28/2010		P4	23,823	A	$5.05(12)	2,100,529	I	By Icarus Investment Corp.(25)
Common Stock	06/29/2010		P4	9,000	A	$4.68(13)	2,109,529	I	By Icarus Investment Corp.(25)
Common Stock	06/30/2010		P4	5,900	A	$4.7(14)	2,115,429	I	By Icarus Investment Corp.(25)
Common Stock	07/01/2010		P4	500	A	$4.65	2,115,929	I	By Icarus Investment Corp.(25)
Common Stock	07/06/2010		P4	800	A	$4.87(15)	2,116,729	I	By Icarus Investment Corp.(25)
Common Stock	07/07/2010		P4	800	A	$4.87(16)	2,117,529	I	By Icarus Investment Corp.(25)
Common Stock	07/09/2010		P4	1,000	A	$5.13(17)	2,118,529	I	By Icarus Investment Corp.(25)
Common Stock	07/14/2010		P4	16,800	A	$5.05(18)	2,135,329	I	By Icarus Investment Corp.(25)
Common Stock	07/21/2010		P4	14,500	A	$5.05	2,149,829	I	By Icarus Investment Corp.(25)
Common Stock	12/21/2010		P4	13,000	A	$5.34(19)	2,162,829	I	By Icarus Investment Corp.(25)
Common Stock	12/22/2010		P4	3,000	A	$5.24(20)	2,165,829	I	By Icarus Investment Corp.(25)
Common Stock	07/15/2008		P4	4,700	A	$4.95	403,129	D
Common Stock	08/26/2008		P4	5,000	A	$4.66(21)	408,129	D
Common Stock	08/27/2008		P4	8,560	A	$4.63(22)	416,689	D
Common Stock	09/05/2008		P4	1,000	A	$5.01(23)	417,689	D
Common Stock	09/08/2008		P4	17,126	A	$4.84(24)	434,815	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)	5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
					(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The price reported in column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.49 to $3.58, inclusive. The reporting person undertakes to provide to CECO Environmental Corp., any security holder of CECO Environmental Corp., or the staff of the Securities Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes 1 through 24 in this Form 5.

2. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.55 to $3.61, inclusive.

3. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.21 to $5.30, inclusive.

4. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.65 to $5.14, inclusive.

5. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.99 to $5.26, inclusive.

6. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.97 to $5.10, inclusive.

7. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.60 to $4.79, inclusive.

8. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.00 to $5.06, inclusive.

9. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.89 to $4.90, inclusive.

10. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.67 to $4.85, inclusive.

11. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.65 to $4.85, inclusive.

12. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.92 to $5.17, inclusive.

13. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.65 to $4.71, inclusive.

14. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.66 to $4.73, inclusive.

15. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.81 to $4.89, inclusive.

16. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.81 to $4.89, inclusive.

17. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.11 to $5.14, inclusive.

18. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.01 to $5.10, inclusive.

19. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.33 to $5.36, inclusive.

20. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $5.21 to $5.25, inclusive.

21. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.65 to $4.66, inclusive.

22. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.61 to $4.66, inclusive.

23. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.89 to $5.12, inclusive.

24. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.72 to $4.97, inclusive.

25. Filer is President of Icarus Investment Corp. and disclaims beneficial ownership of these securities except to the extent of his pecuniary interest, if any, therein.

Remarks:

6 of 8.

	/s/ Phillip DeZwirek	05/31/2011
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
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