Waystar Holding Corp. Officer's Stock Ownership and Power of Attorney

The filing discloses the stock ownership of William Chan, Chief Product & AI Officer at Waystar Holding Corp., who owns 1,498,541 shares of common stock. Additionally, it includes a Power of Attorney document that appoints Gregory R. Packer, Joshua C. Horrocks, and Steven M. Oreskovich as attorneys-in-fact to handle SEC filings related to Chan's ownership and transactions in Waystar Holding Corp. securities. The Power of Attorney remains effective until Chan is no longer required to file Forms 3, 4, and 5, unless revoked earlier.