Form 4 Filing by Richard F. Wallman

Richard F. Wallman, a director at CECO ENVIRONMENTAL CORP, reported the acquisition of 10,000 shares of common stock on April 29, 2026, at a price of $73.25 per share. This transaction was a purchase, increasing his direct ownership to 229,909 shares. Additionally, a separate transaction on the same date involved the acquisition of 5,000 shares of common stock, with a weighted average purchase price ranging from $73.78 to $73.80. This indirect ownership, held by his spouse, resulted in 85,500 shares. The filing was signed on May 1, 2026, by his attorney-in-fact.