X0306 4 2016-12-08 0 0000003197 CECO ENVIRONMENTAL CORP CECE 0000946589 DEZWIREK JASON 2300 YONGE STREET, SUITE 1710 TORONTO A6 M4P 1E4 ONTARIO, CANADA 1 0 1 0 Common Stock 1377974 D Common Stock 2016-12-08 4 X 0 250000 9.07 A 2869906 I By Icarus Investment Corp. Common Stock 2016-12-08 4 D 0 160360 14.14 D 2709546 I By Icarus Investment Corp. Warrant (right to buy) 9.07 2016-12-08 4 X 0 250000 0.00 D 2006-12-28 2016-12-28 Common Stock 250000 0 I By Icarus Investment Corp. Filer is an officer of Icarus Investment Corp. ("Icarus") and disclaims beneficial ownership except to the extent of his pecuniary interest therein. On December 8, 2016, Icarus exercised in full a warrant to purchase 250,000 shares of common stock of CECO Environmental Corp. ("CECO") for $9.07 per share. Icarus paid the exercise price on a cashless basis pursuant to the terms of the warrant agreement governing the warrant, resulting in CECO's withholding of 160,360 of the warrant shares to pay the exercise price and issuing to Icarus the remaining 89,640 of the warrant shares. The payment of the exercise price of the warrant on a cashless basis was previously approved by the Compensation Committee of the Board of Directors of CECO for purposes of Rule 16b-3(e) under the Securities Exchange Act of 1934. /s/ Jason DeZwirek 2016-12-09