[Form 3] Avidia Bancorp, Inc. Initial Statement of Beneficial Ownership

Rhea-AI Filing Summary

Michael O. Gilles, a director of Avidia Bancorp, Inc. (AVBC), reported beneficial ownership following a 09/25/2025 event. He holds 24,096 shares directly plus 16,000 shares held in an IRA, 3,000 shares held by his spouse, and 1,300 shares held as custodian for a grandchild, totaling 44,396 shares. The Form 3 was signed under power of attorney on 10/02/2025 by Victor L. Cangelosi.

Positive

• Director disclosed total beneficial ownership of 44,396 shares
• Filing separates direct and indirect holdings (IRA, spouse, custodial), enhancing transparency
• Form 3 filed and signed under power of attorney, documenting compliance with Section 16 reporting

Negative

• None.

Insights

Financial Analyst

TL;DR: Director disclosed a modest personal stake totaling 44,396 shares; ownership is transparent but not clearly material to valuation.

The filing shows a clear breakdown of direct and indirect holdings: 24,096 shares directly owned and the remainder held via IRA, spouse, and custodial accounts. For most investors this level of ownership by a director is routine and does not alone imply a change to company control or valuation. The timing indicates this is an initial Section 16 disclosure following a qualifying event on 09/25/2025. No derivative positions or transactions are reported.

Corporate Governance Expert

TL;DR: Proper Section 16 disclosure was filed by a director, providing expected transparency into insider holdings.

The Form 3 identifies the reporting person as a director and lists direct and indirect beneficial ownership categories, satisfying initial insider disclosure requirements. The signature via power of attorney is documented with date. There are no indications of related-party transactions, option grants, or other governance concerns within this filing.

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0104
Estimated average burden
hours per response:			0.5

1. Name and Address of Reporting Person^*

GILLES MICHAEL O

(Last) (First) (Middle)

42 MAIN ST

(Street)

HUDSON MA 01749

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
09/25/2025

3. Issuer Name and Ticker or Trading Symbol
Avidia Bancorp, Inc. [ AVBC ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	24,096	D
Common Stock	16,000	I	By IRA
Common Stock	3,000	I	By Spouse
Common Stock	1,300	I	As custodian for grandchild

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

	/s/ Victor L. Cangelosi, pursuant to power of attorney	10/02/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did Michael O. Gilles report on the Form 3 for AVBC?

He reported 24,096 shares directly plus 16,000 shares in an IRA, 3,000 by spouse, and 1,300 as custodian, totaling 44,396 shares.

What is the reporting person's relationship to Avidia Bancorp (AVBC)?

The Form 3 identifies the reporting person as a Director of Avidia Bancorp, Inc.

When did the event requiring this Form 3 occur?

The Date of Event requiring the statement is 09/25/2025.

Was the Form 3 signed and who signed it?

The form was signed by Victor L. Cangelosi pursuant to power of attorney on 10/02/2025.

Are any derivative securities or options reported on this Form 3?

No. The filing contains no derivative securities, options, or convertible instruments.