Assembly Biosciences's top three insider shareholders as of March 23, 2026 are Sciences, Inc. Gilead (TenPercentOwner, 4.51Mn shares), Alexander Schornstein (TenPercentOwner, 728.11K shares), Michael P. Samar (Chief Financial Officer, 77.23K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Sciences, Inc. Gilead | 4,505,391 | 0 | 03 Oct, 2025 | |
| Alexander Schornstein | 728,113 | 0 | 25 Nov, 2024 | |
| Michael P. Samar | Chief Financial Officer | 77,228 | 0 | 26 Jul, 2022 |
| Thomas Joseph Russo | Cfo | 54,633 | 0 | 02 Apr, 2021 |
| Luisa M Stamm | Chief Medical Officer | 40,315 | 0 | 31 Mar, 2022 |
| John G Mchutchison | 18,347 | 0 | 15 Apr, 2025 | |
| William E Iv Delaney | Chief Scientific Officer | 16,109 | 0 | 01 May, 2024 |
| Jason A Okazaki | Ceo And President | 14,757 | 0 | 01 Apr, 2025 |
| Nicole S White | Chief Manufacturing Officer | 11,674 | 0 | 01 Apr, 2025 |
| Jeanette M Bjorkquist | Pfo And Pao | 5,097 | 0 | 17 Jun, 2025 |
| Michael Houghton | 0 | 3,202 | 31 Dec, 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 |
|---|---|---|---|---|---|---|---|---|
| 08 Aug, 2025 | Sciences, Inc. Gilead | Common Stock | A | 2,295,920 | - | 4,505,391 | D | P |
| 08 Aug, 2025 | Sciences, Inc. Gilead | Class A warrants to purchase Common Stock | A | 1,147,960 | - | 1,147,960 | D | P |
| 08 Aug, 2025 | Sciences, Inc. Gilead | Class B warrants to purchase Common Stock | A | 1,147,960 | - | 1,147,960 | D | P |
| 16 Jun, 2025 | Jeanette M Bjorkquist | Common Stock | A | 300 | $0.00 | 5,097 | D | A |
| 16 Jun, 2025 | Jeanette M Bjorkquist | Stock Option (right to buy) | A | 600 | $0.00 | 600 | D | A |
| 05 Jun, 2025 | Michael Houghton | Stock Option (right to buy) | A | 3,500 | $0.00 | 3,500 | D | A |
| 05 Jun, 2025 | William R Ringo | Stock Option (right to buy) | A | 3,500 | $0.00 | 3,500 | D | A |
| 05 Jun, 2025 | Susan Mahony | Stock Option (right to buy) | A | 3,500 | $0.00 | 3,500 | D | A |
| 05 Jun, 2025 | Lisa Johnson-Pratt | Stock Option (right to buy) | A | 3,500 | $0.00 | 3,500 | D | A |
| 05 Jun, 2025 | John G Mchutchison | Stock Option (right to buy) | A | 3,500 | $0.00 | 3,500 | D | A |
| 05 Jun, 2025 | Gina Consylman | Stock Option (right to buy) | A | 3,500 | $0.00 | 3,500 | D | A |
| 31 Mar, 2025 | John G Mchutchison | Common Stock | D | 757 | $9.85 | 18,347 | D | S |
| 29 Mar, 2025 | Jeanette M Bjorkquist | Common Stock | A | 1,655 | $0.00 | 4,797 | D | A |
| 29 Mar, 2025 | Anuj Gaggar | Stock Option (right to buy) | A | 24,200 | $0.00 | 24,200 | D | A |
| 31 Mar, 2025 | Jason A Okazaki | Common Stock | D | 355 | $9.85 | 14,757 | D | S |
| 31 Mar, 2025 | Nicole S White | Common Stock | D | 197 | $9.85 | 11,674 | D | S |
| 29 Mar, 2025 | William E Iv Delaney | Stock Option (right to buy) | A | 25,500 | $0.00 | 25,500 | D | A |
| 31 Mar, 2025 | Jeanette M Bjorkquist | Common Stock | D | 180 | $9.85 | 4,617 | D | S |
| 29 Mar, 2025 | Nicole S White | Stock Option (right to buy) | A | 20,400 | $0.00 | 20,400 | D | A |
| 29 Mar, 2025 | Jason A Okazaki | Stock Option (right to buy) | A | 71,100 | $0.00 | 71,100 | D | A |