As of March 23, 2026, Maxcyte's top three insider holders are Partners Master Fund, L.P. Casdin (TenPercentOwner, 10.00Mn shares), Stanley C Erck (Director, 398.33K shares), Art Mandell (Director, 395.85K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Art Mandell | 395,851 | 0 | 13 Jun, 2024 | |
| Maher Masoud | President And Ceo | 175,000 | 0 | 13 Aug, 2025 |
| Douglas J Swirsky | Chief Financial Officer | 151,669 | 0 | 19 Mar, 2026 |
| David I. Sandoval | General Counsel | 64,219 | 0 | 20 Mar, 2025 |
| Ali Soleymannezhad | Chief Commercial Officer | 59,439 | 0 | 20 Mar, 2025 |
| Thomas M. Ross | Evp, Global Sales | 25,000 | 0 | 05 Aug, 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 |
|---|---|---|---|---|---|---|---|---|
| 17 Mar, 2026 | Douglas J Swirsky | Common Stock | D | 10,142 | $0.82 | 151,669 | D | S |
| 13 Aug, 2025 | Douglas J Swirsky | Common Stock | A | 50,000 | $1.29 | 161,811 | D | P |
| 13 Aug, 2025 | Maher Masoud | Common Stock | A | 75,000 | $1.37 | 175,000 | D | P |
| 18 Mar, 2025 | Douglas J Swirsky | Common Stock | D | 6,939 | $3.18 | 111,811 | D | S |
| 18 Mar, 2025 | Ali Soleymannezhad | Common Stock | D | 1,211 | $3.18 | 59,439 | D | S |
| 18 Mar, 2025 | David I. Sandoval | Common Stock | D | 353 | $3.18 | 64,219 | D | S |
| 14 Mar, 2025 | Ali Soleymannezhad | Common Stock | A | 34,625 | $0.00 | 60,650 | D | A |
| 14 Mar, 2025 | Douglas J Swirsky | Common Stock | A | 37,500 | $0.00 | 118,750 | D | A |
| 14 Mar, 2025 | Maher Masoud | Employee Stock Option (right to buy) | A | 347,500 | $0.00 | 347,500 | D | A |
| 14 Mar, 2025 | David I. Sandoval | Common Stock | A | 23,125 | $0.00 | 64,572 | D | A |
| 14 Mar, 2025 | David I. Sandoval | Employee Stock Option (right to buy) | A | 92,500 | $0.00 | 92,500 | D | A |
| 14 Mar, 2025 | Douglas J Swirsky | Employee Stock Option (right to buy) | A | 150,000 | $0.00 | 150,000 | D | A |
| 14 Mar, 2025 | Ali Soleymannezhad | Employee Stock Option (right to buy) | A | 138,500 | $0.00 | 138,500 | D | A |
| 13 Jan, 2025 | David I. Sandoval | Common Stock | D | 4,466 | $4.54 | 41,447 | D | S |
| 16 Sep, 2024 | Ali Soleymannezhad | Common Stock | A | 10,400 | $0.00 | 26,025 | D | A |
| 16 Sep, 2024 | Ali Soleymannezhad | Employee Stock Option (right to buy) | A | 20,800 | $0.00 | 20,800 | D | A |
| 01 Aug, 2024 | Thomas M. Ross | Common Stock | A | 15,476 | $1.64 | 40,476 | D | M |
| 01 Aug, 2024 | Thomas M. Ross | Common Stock | D | 15,476 | $4.54 | 25,000 | D | S |
| 02 Aug, 2024 | Thomas M. Ross | Common Stock | A | 17,857 | $1.64 | 42,857 | D | M |
| 02 Aug, 2024 | Thomas M. Ross | Common Stock | D | 17,857 | $4.36 | 25,000 | D | S |