Michael O. Gilles Ownership in Avidia Bancorp, Inc.

The filing reports the ownership of Michael O. Gilles in Avidia Bancorp, Inc. as of September 25, 2025. Gilles owns 24,096 shares of common stock directly. Additionally, he holds 16,000 shares indirectly through an IRA, 3,000 shares indirectly through his spouse, and 1,300 shares indirectly as custodian for his grandchild. The total shares owned by Gilles, both directly and indirectly, amount to 44,396 shares. The filing is signed by Victor L. Cangelosi pursuant to a power of attorney.