Rapid Micro Biosystems's top three insider shareholders as of April 22, 2026 are Capital Life Sciences Investors, Llc Bain (TenPercentOwner, 8.43Mn shares), Capital Life Sciences Investors, Llc Bain (TenPercentOwner, 8.43Mn shares), Capital Life Sciences Investors, Llc Bain (TenPercentOwner, 8.43Mn shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Capital Life Sciences Investors, Llc Bain | - | 0 | 8,434,560 | 21 Jul, 2021 |
| Capital Life Sciences Investors, Llc Bain | - | 0 | 8,434,560 | 21 Jul, 2021 |
| Capital Life Sciences Investors, Llc Bain | - | 0 | 8,434,560 | 21 Jul, 2021 |
| Capital Partners Ii, Llc Longitude | - | 0 | 4,029,245 | 03 Feb, 2026 |
| Capital Partners Ii, Llc Longitude | - | 0 | 4,029,245 | 03 Feb, 2026 |
| Capital Partners Ii, Llc Longitude | - | 0 | 4,029,245 | 03 Feb, 2026 |
| David Hirsch | - | 0 | 3,407,952 | 20 Jul, 2021 |
| Lewis Management Lp Kennedy | - | 0 | 2,904,490 | 06 Jun, 2022 |
| Lewis Management Lp Kennedy | - | 0 | 2,904,490 | 06 Jun, 2022 |
| Lewis Management Lp Kennedy | - | 0 | 2,904,490 | 06 Jun, 2022 |
| Richard S Kollender | - | 0 | 1,481,009 | 13 Sep, 2021 |
| Robert G. Jr. Spignesi | President And Ceo | 1,169,848 | 0 | 12 Mar, 2026 |
| Sean M Wirtjes | Chief Financial Officer | 556,194 | 0 | 12 Mar, 2026 |
| John J. Addington Wilson | Chief Operating Officer | 316,762 | 0 | 12 Mar, 2026 |
| Gurinder Grewal | - | 294,990 | 0 | 20 Jul, 2021 |
| Jonathan Paris | Svp, General Counsel | 128,698 | 0 | 13 Mar, 2023 |
| Victoria Vezina | Chief Human Resources Officer | 112,608 | 0 | 12 Mar, 2024 |
| Richard S Kollender | - | 111,018 | 0 | 27 May, 2025 |
| Melinda Litherland Pei | - | 68,600 | 0 | 27 May, 2025 |
| Richard A Keys | Chief Commercial Officer | 43,750 | 0 | 15 Feb, 2022 |
| Inese Lowenstein | - | 38,600 | 0 | 27 May, 2025 |
| Natale S Ricciardi | - | 29,442 | 0 | 02 Mar, 2026 |
| Kirk Malloy | - | 28,600 | 0 | 18 Nov, 2025 |
| David Hirsch | - | 14,300 | 0 | 28 May, 2024 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 11 Mar, 2026 | Sean M Wirtjes | Class A Common Stock | D | 7,480 | $4.32 | 556,194 | D | S |
| 10 Mar, 2026 | Robert G. Jr. Spignesi | Class A Common Stock | D | 17,922 | $4.11 | 1,169,848 | D | S |
| 11 Mar, 2026 | John J. Addington Wilson | Class A Common Stock | D | 9,603 | $4.32 | 316,762 | D | S |
| 27 Feb, 2026 | Natale S Ricciardi | Class A Common Stock | A | 842 | $0.75 | 29,442 | D | M |
| 27 Feb, 2026 | Natale S Ricciardi | Stock Option (Right to Buy) | D | 842 | $0.75 | 0 | D | M |
| 20 Feb, 2026 | Sean M Wirtjes | Class A Common Stock | D | 17,254 | $3.92 | 563,674 | D | S |
| 19 Feb, 2026 | Robert G. Jr. Spignesi | Class A Common Stock | D | 38,327 | $3.89 | 1,187,770 | D | S |
| 20 Feb, 2026 | John J. Addington Wilson | Class A Common Stock | D | 5,403 | $3.92 | 326,365 | D | S |
| 11 Feb, 2026 | John J. Addington Wilson | Class A Common Stock | A | 74,000 | $0.00 | 331,768 | D | A |
| 11 Feb, 2026 | Robert G. Jr. Spignesi | Class A Common Stock | A | 264,000 | $0.00 | 1,226,097 | D | A |
| 11 Feb, 2026 | Sean M Wirtjes | Class A Common Stock | A | 97,000 | $0.00 | 580,928 | D | A |
| 11 Feb, 2026 | John J. Addington Wilson | Stock Option (Right to Buy) | A | 147,000 | $0.00 | 147,000 | D | A |
| 11 Feb, 2026 | Sean M Wirtjes | Stock Option (Right to Buy) | A | 193,000 | $0.00 | 193,000 | D | A |
| 11 Feb, 2026 | Robert G. Jr. Spignesi | Stock Option (Right to Buy) | A | 528,000 | $0.00 | 528,000 | D | A |
| 09 Feb, 2026 | John J. Addington Wilson | Class A Common Stock | D | 4,610 | $3.78 | 257,768 | D | S |
| 09 Feb, 2026 | Sean M Wirtjes | Class A Common Stock | D | 6,027 | $3.78 | 483,928 | D | S |
| 09 Feb, 2026 | Robert G. Jr. Spignesi | Class A Common Stock | D | 12,840 | $3.78 | 962,097 | D | S |
| 04 Feb, 2026 | Capital Partners Ii, Llc Longitude | Class A Common Stock | D | 49,000 | $3.88 | 0 | I | S |
| 23 Jan, 2026 | Capital Partners Ii, Llc Longitude | Class A Common Stock | A | 629,032 | $0.05 | 4,036,984 | I | X |
| 23 Jan, 2026 | Capital Partners Ii, Llc Longitude | Class A Common Stock | D | 7,739 | $4.06 | 4,029,245 | I | S |