Rapid Micro (RPID) COO sells shares to cover RSU tax obligations

Rhea-AI Filing Summary

Rapid Micro Biosystems chief operating officer John J. Addington Wilson reported a sale of 4,610 shares of Class A common stock on February 9, 2026. The shares were sold at $3.7827 per share in an automatic transaction to cover tax obligations from vesting restricted stock units.

Following this transaction, Wilson directly beneficially owned 257,768 Class A shares. This total includes 29,904 shares that were acquired through the company’s employee stock purchase plan on March 14, 2025.

Insider Trade Summary

Net Seller: 4,610 shares ($17,438)

Net Sell 1 txn

Insider Wilson John J. Addington

Role CHIEF OPERATING OFFICER

Sold 4,610 shs ($17K)

Type	Security	Shares	Price	Value
Sale	Class A Common Stock	4,610	$3.7827	$17K

Holdings After Transaction: Class A Common Stock — 257,768 shares (Direct)

Footnotes (1)

1. Represents the automatic sale of stock to cover the associated tax obligations with the vesting of restricted stock units. Includes 29,904 shares acquired under the Rapid Micro Biosystems, Inc. employee stock purchase plan on March 14, 2025.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Wilson John J. Addington

(Last) (First) (Middle)

C/O RAPID MICRO BIOSYSTEMS, INC.

25 HARTWELL AVENUE

(Street)

LEXINGTON MA 02421

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
RAPID MICRO BIOSYSTEMS, INC. [ RPID ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
02/09/2026

4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Class A Common Stock	02/09/2026		S		4,610(1)	D	$3.7827	257,768(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents the automatic sale of stock to cover the associated tax obligations with the vesting of restricted stock units.

2. Includes 29,904 shares acquired under the Rapid Micro Biosystems, Inc. employee stock purchase plan on March 14, 2025.

Remarks:

	/s/ Sean M. Wirtjes, Attorney-in-Fact for John J. Addington Wilson	02/10/2026
	** 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 4 (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 insider transaction did Rapid Micro Biosystems (RPID) report for its COO?

Rapid Micro Biosystems reported that COO John J. Addington Wilson sold 4,610 Class A common shares on February 9, 2026. The sale was executed at $3.7827 per share and disclosed as a routine Form 4 insider transaction.

Why did the Rapid Micro Biosystems (RPID) COO sell 4,610 shares?

The 4,610-share sale by the Rapid Micro Biosystems COO was an automatic sale to cover tax obligations related to vesting restricted stock units. The filing explicitly states the purpose was tax withholding rather than a discretionary open-market sale.

How many Rapid Micro Biosystems (RPID) shares does the COO own after the transaction?

After the reported transaction, COO John J. Addington Wilson beneficially owned 257,768 Class A common shares directly. This total ownership figure reflects holdings following the 4,610-share sale disclosed in the Form 4 insider filing.

What does the Form 4 footnote say about the COO’s Rapid Micro Biosystems (RPID) share sale?

The footnote explains the sale “represents the automatic sale of stock” to cover tax obligations from the vesting of restricted stock units. This clarifies the transaction as tax-related rather than a discretionary reduction of the COO’s investment position.

What additional Rapid Micro Biosystems (RPID) shares are included in the COO’s holdings?

The filing notes that the COO’s holdings include 29,904 shares acquired under the Rapid Micro Biosystems employee stock purchase plan on March 14, 2025. These shares are part of the reported 257,768 Class A shares beneficially owned after the transaction.

Was the Rapid Micro Biosystems (RPID) COO’s ownership reported as direct or indirect?

The Form 4 reports the COO’s ownership of Rapid Micro Biosystems Class A common stock as direct (D). There is no indication in the provided footnotes of shares being held through separate entities or with disclaimed beneficial ownership.