SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 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: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

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. Date of Earliest Transaction (Month/Day/Year) 04/09/2010
	4. If Amendment, Date of Original Filed (Month/Day/Year) 04/12/2010	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 Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	04/09/2010		P		1,484	A	$4.22	397,813	D
Common Stock	04/09/2010		P		100	A	$4.14	397,913	D
Common Stock	04/09/2010		P		16	A	$4.18	397,929	D
Common Stock	04/09/2010		P		200	A	$4.2	398,129	D
Common Stock	04/09/2010		P		300	A	$4.21	398,429(1)	D
Common Stock								940,596(1)	I	By Icarus Investment Corp.(2)
Common Stock								4,700	I	By Retirement Account of spouse

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents amount of such securities owned prior to transactions being reported on a Form 5.

2. 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:

This Form 4/A amends in its entirety the original Form 4 filed to correct the amounts and prices of securities purchased.

	/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).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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