AAON, Inc. expanded its Board of Directors from nine to eleven members by creating two new Class III positions and appointed Robert L. Buttermore III and Patrick J. Jermain as independent directors effective July 28, 2026. Buttermore, currently Senior Vice President and Chief Supply Chain Officer at Rockwell Automation, joins the Compensation Committee, while Jermain, former CFO of Plexus Corporation, serves on the Audit Committee. The Board simultaneously amended its bylaws to increase the maximum board size to eleven positions. These appointments are part of an ongoing succession process aimed at aligning director expertise with the company's scaling operations and long-term growth strategy in commercial HVAC and mission-critical cooling markets.

AAON, INC. participated in the William Blair Growth Stock Conference on June 2, 2026, where executives Matt Tobolski and Andy Cheung provided a presentation. The presentation materials are furnished as Exhibit 99.1 and are not deemed 'filed' for the purpose of Section 18 of the Securities Exchange Act of 1934.