RAPID MICRO BIOSYSTEMS (RPID) director buys shares and receives Series A and B warrants

Rhea-AI Filing Summary

RAPID MICRO BIOSYSTEMS director Melinda Litherland increased her stake through a registered direct offering. She purchased 12,787 shares of Class A Common Stock at $1.955 per share and received accompanying Series A and Series B warrants to buy 12,787 shares each.

Following the transaction, she holds 100,687 Class A shares directly. The Series A warrant has a $1.955 exercise price and expires on May 29, 2027, while the Series B warrant has a $2.34 exercise price and expires on May 29, 2031. Both warrants become exercisable on November 29, 2026 and include a 4.99% beneficial ownership cap.

Insider Trade Summary

3 transactions reported

Mixed 3 txns

Insider PEI MELINDA LITHERLAND

Role null

Type	Security	Shares	Price	Value
Grant/Award	Series A Warrant (right to buy)	12,787	$0.00	--
Grant/Award	Series B Warrant (right to buy)	12,787	$0.00	--
Grant/Award	Class A Common Stock	12,787	$1.955	$25K

Holdings After Transaction: Series A Warrant (right to buy) — 12,787 shares (Direct, null); Series B Warrant (right to buy) — 12,787 shares (Direct, null); Class A Common Stock — 100,687 shares (Direct, null)

Footnotes (1)

1. On May 29, 2026, the Reporting Person purchased, in a registered direct offering, 12,787 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 12,787 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 12,787 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each share of Issuer Class A Common Stock and accompanying Series A and Series B Warrant was $1.955. The issuance of such securities was approved by the Issuer's compensation committee of the board of directors in accordance with Rule 16(b)-3 of the Securities Exchange Act of 1934, as amended. The Series A and Series B Warrants cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 4.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

Key Figures

Shares purchased: 12,787 shares Purchase price: $1.955 per share Shares after transaction: 100,687 shares +5 more

8 metrics

Shares purchased 12,787 shares Class A Common Stock bought in registered direct offering at $1.955

Purchase price $1.955 per share Price per share with accompanying Series A and B warrants

Shares after transaction 100,687 shares Total Class A Common Stock directly held after acquisition

Series A warrant exercise price $1.955 per share Exercise price for 12,787 underlying Class A shares

Series B warrant exercise price $2.34 per share Exercise price for 12,787 underlying Class A shares

Beneficial ownership limit 4.99% Cap on ownership after exercising Series A and B warrants

Series A warrant term Expires May 29, 2027 Exercisable from November 29, 2026 until May 29, 2027

Series B warrant term Expires May 29, 2031 Exercisable from November 29, 2026 until May 29, 2031

Key Terms

registered direct offering, Series A Warrant, Series B Warrant, Rule 16(b)-3, +1 more

5 terms

registered direct offering financial

"purchased, in a registered direct offering, 12,787 shares of the Issuer's Class A Common Stock"

A registered direct offering is a way for a company to sell new shares of its stock directly to select investors with regulatory approval. This method allows the company to raise funds quickly and efficiently without needing a public auction, similar to offering exclusive access to a limited number of buyers. For investors, it often provides an opportunity to purchase shares at a favorable price, while giving the company immediate access to capital.

Series A Warrant financial

"an accompanying Series A Warrant to purchase 12,787 shares of the Issuer's Class A Common Stock"

A Series A warrant is a contract issued alongside a company’s early funding round that gives the holder the right to buy a set number of shares later at a fixed price. Think of it like a coupon that lets an investor purchase stock at today’s agreed price even if the company’s value rises; it can boost potential upside for the warrant holder and create dilution for existing shareholders, so investors watch them when assessing ownership and future share value.

Series B Warrant financial

"an accompanying Series B Warrant to purchase 12,787 shares of the Issuer's Class A Common Stock"

A Series B warrant is a tradable right issued alongside a Series B funding round that lets its holder buy a specified number of company shares at a fixed price for a set period. It matters to investors because exercising the warrant increases the total shares outstanding (dilution) and can be a cheap way to gain ownership if the company’s value rises — think of it like a coupon to buy stock later at today’s price.

Rule 16(b)-3 regulatory

"approved by the Issuer's compensation committee of the board of directors in accordance with Rule 16(b)-3"

beneficially own more than 4.99% financial

"would beneficially own more than 4.99% of the total number of shares"

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

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^*

PEI MELINDA LITHERLAND

(Last) (First) (Middle)

C/O RAPID MICRO BIOSYSTEMS, INC.

25 HARTWELL AVENUE

(Street)

LEXINGTON MASSACHUSETTS 02421

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/29/2026

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

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

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

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	05/29/2026		A(1)		12,787	A	$1.955	100,687	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
Series A Warrant (right to buy)	$1.955	05/29/2026		A(1)		12,787		11/29/2026(2)	05/29/2027	Class A Common Stock	12,787	$0(1)	12,787	D
Series B Warrant (right to buy)	$2.34	05/29/2026		A(1)		12,787		11/29/2026(2)	05/29/2031	Class A Common Stock	12,787	$0(1)	12,787	D

Explanation of Responses:

1. On May 29, 2026, the Reporting Person purchased, in a registered direct offering, 12,787 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 12,787 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 12,787 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each share of Issuer Class A Common Stock and accompanying Series A and Series B Warrant was $1.955. The issuance of such securities was approved by the Issuer's compensation committee of the board of directors in accordance with Rule 16(b)-3 of the Securities Exchange Act of 1934, as amended.

2. The Series A and Series B Warrants cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 4.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

Remarks:

	/s/ Sean M. Wirtjes, Attorney-in-Fact for Melinda Litherland Pei	06/02/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What did Melinda Litherland acquire in the latest RPID Form 4 filing?

Melinda Litherland acquired 12,787 RPID common shares and related warrants. She purchased Class A Common Stock in a registered direct offering and received Series A and Series B warrants, each covering 12,787 underlying shares of Class A Common Stock as part of that transaction.

What prices and terms apply to the new RPID warrants reported for Melinda Litherland?

The Series A warrant has a $1.955 exercise price; Series B is $2.34. Both are exercisable starting November 29, 2026. The Series A warrant expires May 29, 2027, and the Series B warrant expires May 29, 2031, each for 12,787 underlying shares.

How many RAPID MICRO BIOSYSTEMS shares does Melinda Litherland hold after this Form 4?

After the reported transactions, Melinda Litherland holds 100,687 Class A shares directly. This total reflects her position following the purchase of 12,787 shares in the registered direct offering disclosed in the Form 4 filing.

What is the purchase price disclosed for Melinda Litherland’s new RPID shares and warrants?

The purchase price was $1.955 for each share plus accompanying warrants. Each unit consisted of one Class A Common Share, one Series A Warrant, and one Series B Warrant, all sold together at $1.955 per share with the two warrants attached.

Is there a beneficial ownership limit on Melinda Litherland’s new RPID warrants?

Yes, the Series A and B warrants include a 4.99% ownership cap. They cannot be exercised if doing so would cause the holder, together with affiliates and related persons, to beneficially own more than 4.99% of RPID’s outstanding Class A Common Stock.