Form 4 Filing for Avidia Bancorp, Inc.

Jonathan Michael Nelson, CFO and Treasurer of Avidia Bancorp, Inc., acquired 76,000 shares of Common Stock on October 13, 2026, at a price of $0.0 per share. This transaction, marked as an acquisition, resulted in a post-transaction ownership of 95,045 shares. Additionally, Mr. Nelson was granted 190,000 Stock Options with an exercise price of $21.95, vesting 20% annually starting October 13, 2027, and expiring on October 13, 2036. His indirect ownership includes 22,550 shares of Common Stock held in a 401(k).