Every Form 4 that Rapid Micro Biosystems, Inc. (RPID) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow RPID and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full RPID filings page.
Rapid Micro Biosystems, Inc. director Richard S. Kollender reported exercising stock options covering a total of 3,508 shares of Class A Common Stock on 2026-07-24. The options, described as fully vested and exercisable, were exercised at an exercise price of $0.7500 per share in two tranches of 1,681 and 1,827 underlying shares.
Rapid Micro Biosystems, Inc. reports that President and CEO Robert G. Spignesi Jr. exercised a stock option for 1,402 shares of Class A Common Stock on July 22, 2026 at an exercise price of $0.75 per share. The underlying option, which was fully vested and exercisable and scheduled to expire on August 11, 2026, was fully exercised and no longer remains outstanding. Following this transaction, Spignesi directly holds 1,191,973 shares of Class A Common Stock, with no shares sold in this filing.
Rapid Micro Biosystems director Inese Lowenstein increased her stake through a combined share purchase and warrant grant. On May 29, 2026, she acquired 12,787 shares of Class A Common Stock at $1.955 per share in a registered direct offering, together with Series A and Series B Warrants to purchase 12,787 shares each. 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. After this transaction, she directly holds 70,687 Class A shares. The warrants are subject to a 4.99% beneficial ownership cap that restricts exercises that would push her above that ownership level.
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.
Rapid Micro Biosystems director Kirk Malloy increased his stake through a registered direct offering. On May 29, 2026, he purchased 12,787 shares of Class A Common Stock together with an accompanying Series A Warrant and Series B Warrant, each to buy 12,787 additional shares, for a combined purchase price of $1.955 per share plus both warrants.
Following the transactions, Malloy holds 60,687 shares directly and 10,000 shares indirectly through a family trust. The Series A Warrant is exercisable at $1.955 per share from November 29, 2026 until May 29, 2027, and the Series B Warrant at $2.340 per share from November 29, 2026 until May 29, 2031. Both warrants include a 4.99% beneficial ownership cap on exercise.
RAPID MICRO BIOSYSTEMS, INC. Chief Financial Officer Sean M. Wirtjes acquired 12,787 shares of Class A Common Stock in a registered direct offering at $1.955 per share, together with accompanying Series A and Series B warrants for 12,787 shares each.
The Series A Warrant has a $1.955 exercise price and expires on May 29, 2027, while the Series B Warrant has a $2.340 exercise price and expires on May 29, 2031. After these awards, he directly holds 568,981 shares of Class A Common Stock and 12,787 Series A and 12,787 Series B warrants. Both warrant series are subject to a 4.99% beneficial ownership cap on exercise.
RAPID MICRO BIOSYSTEMS, INC. President and CEO Robert G. Spignesi Jr. reported acquiring 12,787 shares of Class A Common Stock at $1.955 per share in a registered direct offering. With this grant and prior holdings, he now directly owns 1,190,571 shares of Class A Common Stock.
He also received a Series A Warrant and a Series B Warrant, each covering 12,787 shares of Class A Common Stock. The Series A Warrant has an exercise price of $1.955 and expires on May 29, 2027, while the Series B Warrant has an exercise price of $2.34 and expires on May 29, 2031. Both warrants are subject to a 9.99% beneficial ownership cap, limiting exercises that would push total beneficial ownership above that threshold.
RAPID MICRO BIOSYSTEMS, INC. director Kirk Malloy reported equity compensation awards on Class A Common Stock. He received 19,300 restricted stock units (RSUs) at no cash cost, increasing his directly held common shares to 47,900 after the award.
He was also granted a stock option for 38,700 shares of Class A Common Stock with an exercise price of $2.0700 per share, expiring on May 20, 2036. Both the RSUs and the option vest in full on the earlier of the first anniversary of the grant date or immediately before the next annual stockholders’ meeting, if he remains in continuous service. In addition, an indirect holding of 10,000 shares is reported in a family trust where he shares investment power.
RAPID MICRO BIOSYSTEMS, INC. director Inese Lowenstein reported new equity compensation awards. She received 19,300 shares of Class A common stock as restricted stock units that vest in full on the earlier of the first anniversary of the grant date or the day immediately prior to the next annual stockholder meeting, provided she remains in continuous service.
She was also granted a stock option for 38,700 shares of Class A common stock at an exercise price of $2.07 per share, with the option vesting on the same schedule. After the grant, she directly holds 57,900 shares of Class A common stock and 38,700 options.
RAPID MICRO BIOSYSTEMS, INC. director Melinda Litherland received equity-based compensation consisting of restricted stock units and stock options.
She was granted 19,300 shares of Class A Common Stock as restricted stock units that vest in full on the earlier of the first anniversary of the grant date or the day immediately before the next annual stockholder meeting, if she remains in continuous service.
She was also granted options on 38,700 shares of Class A Common Stock at an exercise price of $2.07 per share, which vest on the same schedule and expire on May 20, 2036. Following these grants, she directly owns 87,900 shares of Class A Common Stock.
Rapid Micro Biosystems, Inc. director Richard S. Kollender reported equity awards under the company’s compensation program. He received 19,300 shares of Class A common stock as restricted stock units that were granted at no cash cost.
He was also granted stock options for 38,700 shares of Class A common stock at an exercise price of $2.07 per share, expiring on May 20, 2036. Both the RSUs and the options vest in full on the earlier of the first anniversary of the grant date or immediately before the next annual stockholders’ meeting, assuming continuous service. Following the RSU grant, he directly holds 130,318 shares of Class A common stock.
RAPID MICRO BIOSYSTEMS, INC. director Dafni Bika received new equity awards. She was granted 19,300 shares of Class A Common Stock as restricted stock units and 38,700 stock options with a $2.07 exercise price. Both the RSUs and options vest in full on the earlier of the first anniversary of the grant date or immediately before the next annual stockholders meeting, contingent on continuous service.
Rapid Micro Biosystems disclosed that Bain Capital Life Sciences–affiliated entity BCLS I Investco, LP bought a package of warrants in an underwritten public offering. BCLS I Investco acquired a Pre-Funded Warrant, an accompanying Series A Warrant, and an accompanying Series B Warrant, each giving the right to purchase 1,463,000 shares of Class A Common Stock. The combined unit price for each pre-funded warrant plus Series A and Series B Warrants was $1.945. The pre-funded warrant has a $0.01 exercise price and does not expire, while the Series A and Series B Warrants have exercise prices of $1.955 and $2.34, respectively, and stated future exercise periods. All three warrants are subject to a 9.99% beneficial ownership limit. The Bain Capital Life Sciences entities also report indirect ownership of 8,434,560 shares of Class A Common Stock following the transaction.
RAPID MICRO BIOSYSTEMS, INC. chief operating officer John J. Addington reported an automatic sale of 9,603 shares of Class A common stock at an average price of $4.3181 per share. The shares were sold to cover tax obligations arising from the vesting of restricted stock units, according to the footnote.
After this transaction, he directly holds 316,762 shares of Class A common stock, indicating the sale represents a small portion of his overall position and is tied to routine equity-compensation tax withholding rather than discretionary selling.
RAPID MICRO BIOSYSTEMS, INC. Chief Financial Officer Sean M. Wirtjes reported an automatic sale of 7,480 shares of Class A Common Stock. The shares were sold at an average price of $4.3181 per share to cover tax obligations arising from the vesting of restricted stock units. After this tax-related sale, he directly holds 556,194 shares, indicating he retains a substantial equity position in the company.
RAPID MICRO BIOSYSTEMS, INC. president and CEO Robert G. Spignesi Jr. reported an automatic sale of 17,922 shares of Class A common stock at $4.1115 per share on March 10, 2026.
The footnote explains this sale was made solely to cover tax obligations related to the vesting of restricted stock units. After the transaction, he directly owned 1,169,848 shares, indicating this was a small, routine disposition relative to his overall stake.
RAPID MICRO BIOSYSTEMS, INC. director Natale S. Ricciardi exercised a stock option and acquired Class A common shares. On February 27, 2026, he exercised an option for 842 shares at an exercise price of $0.75 per share. Following the exercise, his direct holdings of Class A common stock increased to 29,442 shares. The footnote indicates the option was already fully vested and exercisable, meaning this transaction reflects the use of an existing equity award rather than a new grant or open-market purchase.
RAPID MICRO BIOSYSTEMS, INC. chief operating officer John J. Wilson reported an automatic sale of 5,403 shares of Class A common stock at $3.923 per share. According to the footnote, this sale was made solely to cover tax obligations tied to vesting restricted stock units. After the transaction, he directly held 326,365 shares of Class A common stock.
RAPID MICRO BIOSYSTEMS, INC. Chief Financial Officer Sean M. Wirtjes reported an automatic sale of Class A common stock to cover taxes tied to restricted stock unit vesting. He sold 17,254 shares at an average price of $3.923 per share. After this tax-related sale, he continues to hold 563,674 shares directly.
RAPID MICRO BIOSYSTEMS, INC. president and CEO Robert G. Spignesi Jr. reported a sale of 38,327 shares of Class A common stock on February 19, 2026 at an average price of $3.8853 per share. A footnote explains this was an automatic sale to cover tax obligations arising from the vesting of restricted stock units, rather than a discretionary open-market trade. After this transaction, he still holds 1,187,770 shares of the company’s Class A common stock directly.
Rapid Micro Biosystems chief operating officer John J. Addington Wilson received new equity awards as part of his compensation. He was granted 74,000 shares of Class A common stock, reported at a price of $0 and bringing his direct holdings to 331,768 shares. These shares represent restricted stock units that vest over three years, with 33.4% vesting on the first anniversary of February 11, 2026 and 33.3% on each of the next two anniversaries, conditioned on continued service. He was also granted a stock option for 147,000 shares of Class A common stock with a $4.20 exercise price, expiring on February 10, 2036. The option vests in 48 equal monthly installments starting March 11, 2026, leaving him with 147,000 options beneficially owned after the transaction.
Rapid Micro Biosystems, Inc. reported an equity compensation grant to its Chief Financial Officer, Sean M. Wirtjes. On February 11, 2026, he received 97,000 Class A common stock restricted stock units, awarded at $0 per share, increasing his directly held Class A shares to 580,928 after the grant.
He was also granted a stock option for 193,000 shares of Class A common stock with an exercise price of $4.2 per share. The RSUs vest in three annual installments starting on the first anniversary of the grant date, while the option vests in 48 equal monthly installments beginning March 11, 2026, contingent on continued service.
Rapid Micro Biosystems, Inc. President and CEO Robert G. Spignesi Jr., who is also a director, reported equity compensation awards. He received 264,000 shares of Class A common stock on February 11, 2026 as a grant of restricted stock units that vest over three years.
The RSUs vest in three annual installments, with 33.4% vesting on the first anniversary of the February 11, 2026 grant date and 33.3% vesting on each of the next two anniversaries, subject to continued service. He was also granted a stock option covering 528,000 shares at an exercise price of $4.20 per share, vesting in 48 equal monthly installments starting March 11, 2026 and expiring February 10, 2036. Following these awards, he directly beneficially owns 1,226,097 shares of Class A common stock and 528,000 stock options.
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.
Rapid Micro Biosystems chief financial officer Sean M. Wirtjes reported an automatic sale of shares to cover taxes tied to equity compensation. On February 9, 2026, he sold 6,027 shares of Class A common stock at $3.7827 per share in a transaction coded as a sale. The filing states this sale was made automatically to satisfy tax obligations arising from the vesting of restricted stock units. After this transaction, Wirtjes directly owned 483,928 shares of Rapid Micro Biosystems Class A common stock.
Rapid Micro Biosystems, Inc. President and CEO Robert G. Spignesi Jr. reported an automatic sale of Class A common stock. On 02/09/2026, he sold 12,840 shares at $3.7827 per share to cover tax obligations related to vesting restricted stock units. After this transaction, he beneficially owned 962,097 shares directly.
Rapid Micro Biosystems, Inc. insider entities reported a share sale and updated holdings. On February 4, 2026, Longitude Prime Fund, L.P. reported an indirect sale of 49,000 shares of Class A common stock at $3.8794 per share, leaving it with no reported shares afterward.
Separately, Longitude Venture Partners II, L.P. reported continued indirect beneficial ownership of 4,029,245 shares of Class A common stock. General partner entities and individuals associated with these funds may be deemed to share voting and dispositive power but expressly disclaim beneficial ownership beyond their pecuniary interests.
Rapid Micro Biosystems, Inc. (RPID) reported insider activity involving investment funds managed by Longitude Capital. Longitude Venture Partners II, L.P. exercised warrants for 629,032 shares of Class A common stock at $0.05 per share on a cashless basis, with 7,739 shares withheld to cover the exercise price.
After these transactions, Longitude Venture Partners II, L.P. held 4,029,245 Class A shares indirectly. Separate from this, Longitude Prime Fund, L.P. sold 46,000, 27,500 and 27,500 Class A shares on January 30, 2026, February 2, 2026 and February 3, 2026 at prices between $4.24 and $4.54 per share, leaving it with 49,000 shares owned indirectly.
The filing explains that Longitude Capital Partners II, LLC and Longitude Prime Partners, LLC are general partners of the respective funds, and individuals Patrick G. Enright and Juliet Tammenoms Bakker are managing members, all disclaiming beneficial ownership beyond their pecuniary interests.
Rapid Micro Biosystems, Inc. (RPID) director Kirk Malloy reported a charitable gift of 40,000 shares of the company’s Class A common stock on 11/14/2025. The transaction was coded as a gift at a reported price of $0, reflecting that it was a non-sale transfer to a non-profit charitable organization.
After this transaction, Malloy beneficially owns 28,600 shares directly and an additional 10,000 shares indirectly through a family trust in which he shares investment power and where he and/or immediate family members are beneficiaries.
Rapid Micro Biosystems (RPID) reported insider transactions by President & CEO and Director Robert G. Spignesi, Jr. on 10/17/2025. He exercised stock options (code M) for 3,400 and 7,833 shares at an exercise price of $0.75 per share via net exercise. The company withheld 2,072 and 4,774 shares (code F) using the $3.08 closing price to cover the exercise price and taxes, consistent with the 2010 Stock Option and Grant Plan. Following these transactions, he directly owned 974,937 Class A common shares.