[Form 4] Ceco Environmental Corp Insider Trading Activity

Insider Trade Summary

Net Seller: 20,000 shares ($830,247)

Net Sell 4 txns

Insider Mannarino Claudio A

Role Director

Sold 20,000 shs ($830K)

Type	Security	Shares	Price	Value
Sale	Common Stock	7,759	$41.9785	$326K
Sale	Common Stock	11,801	$41.2469	$487K
Sale	Common Stock	440	$40.4109	$18K
holding	Restricted Stock Units	--	--	--

Holdings After Transaction: Common Stock — 89,830 shares (Direct); Restricted Stock Units — 6,006 shares (Direct)

Footnotes (1)

1. Price reflects the weighted average sale price for multiple transactions that ranged from $41.54 to $42.54 per share. The Reporting Person undertakes to provide, upon request by the Commission Staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reflects the weighted average sale price for multiple transactions that ranged from $40.56 to $41.53 per share. The Reporting Person undertakes to provide, upon request by the Commission Staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reflects the weighted average sale price for multiple transactions that ranged from $40.41 to $41.42 per share. The Reporting Person undertakes to provide, upon request by the Commission Staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. Represents restricted stock units granted under the CECO Environmental Corp. Deferred Compensation Plan for Non-Employee Directors. Each restricted stock unit represents a contingent right to receive one share of the Company's common stock. Conversion of restricted stock units to the Company's common stock and distribution of such stock under the Deferred Compensation Plan is deferred until termination of service as a Company director.

Form 4 Insider Transactions: What Each Field Means →

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).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Mannarino Claudio A

(Last) (First) (Middle)

5080 SPECTRUM DRIVE

SUITE 800E

(Street)

ADDISON TX 75001

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
CECO ENVIRONMENTAL CORP [ CECO ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
07/30/2025

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 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	07/30/2025		S		7,759	D	$41.9785(1)	89,830	D
Common Stock	07/30/2025		S		11,801	D	$41.2469(2)	78,029	D
Common Stock	07/30/2025		S		440	D	$40.4109(3)	77,589	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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	(4)							(5)	(5)	Common Stock	6,006		6,006	D

Explanation of Responses:

1. Price reflects the weighted average sale price for multiple transactions that ranged from $41.54 to $42.54 per share. The Reporting Person undertakes to provide, upon request by the Commission Staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

2. Price reflects the weighted average sale price for multiple transactions that ranged from $40.56 to $41.53 per share. The Reporting Person undertakes to provide, upon request by the Commission Staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

3. Price reflects the weighted average sale price for multiple transactions that ranged from $40.41 to $41.42 per share. The Reporting Person undertakes to provide, upon request by the Commission Staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

4. Represents restricted stock units granted under the CECO Environmental Corp. Deferred Compensation Plan for Non-Employee Directors. Each restricted stock unit represents a contingent right to receive one share of the Company's common stock.

5. Conversion of restricted stock units to the Company's common stock and distribution of such stock under the Deferred Compensation Plan is deferred until termination of service as a Company director.

	/s/ Kiril Kovachev as Attorney-in-Fact for Claudio Mannarino	08/01/2025
	** 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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