RAPID MICRO BIOSYSTEMS, INC. — Director's Dealing 2025

Oct 21, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: RAPID MICRO BIOSYSTEMS, INC. (RPID)
CIK: 0001380106
Period of Report: 2025-10-17

Reporting Person: Spignesi Robert G. Jr. (Director, PRESIDENT AND CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-10-17	Class A Common Stock	M	3400	$0.75	Acquired	973950	Direct
2025-10-17	Class A Common Stock	F	2072	$3.08	Disposed	971878	Direct
2025-10-17	Class A Common Stock	M	7833	$0.75	Acquired	979711	Direct
2025-10-17	Class A Common Stock	F	4774	$3.08	Disposed	974937	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-10-17	Stock Option (Right to Buy)	$0.75	M	3400	Disposed	2025-10-22	Class A Common Stock (3400)	Direct
2025-10-17	Stock Option (Right to Buy)	$0.75	M	7833	Disposed	2025-10-22	Class A Common Stock (7833)	Direct

Footnotes

F1: Represents a "net exercise" of outstanding stock options. The reporting person received 1,328 shares of common stock on net exercise of option to purchase 3,400 shares of common stock. The Company withheld 2,072 shares of common stock underlying the option for payment of the exercise price and tax withholdings, using the closing stock price on October 17, 2025 of $3.08, pursuant to the terms of the 2010 Stock Option and Grant Plan.

F2: Represents a "net exercise" of outstanding stock options. The reporting person received 3,059 shares of common stock on net exercise of option to purchase 7,833 shares of common stock. The Company withheld 4,774 shares of common stock underlying the option for payment of the exercise price and tax withholdings, using the closing stock price on October 17, 2025 of $3.08, pursuant to the terms of the 2010 Stock Option and Grant Plan.

F3: The option is fully vested and exercisable.