As of September 29, 2026, the three largest insider holders of ARCT are Joseph E Payne (President And Ceo, 1.48Mn shares), Pad Chivukula (Chief Scientific Officer Coo, 435.33K shares), Andy Sassine (Chief Financial Officer, 221.76K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Joseph E Payne | President And Ceo | 1,480,097 | 0 | 1,480,097 | 66.7% | 28 Nov, 2022 |
| 2 | Pad Chivukula | Chief Scientific Officer Coo | 435,334 | 0 | 435,334 | 19.6% | 16 Oct, 2024 |
| 3 | Andy Sassine | Chief Financial Officer | 221,764 | 0 | 221,764 | 10.0% | 20 Aug, 2025 |
| 4 | Peter C Farrell | Director | 55,741 | 0 | 55,741 | 2.5% | 18 Jun, 2024 |
| 5 | James F Barlow | Director | 13,131 | 0 | 13,131 | 0.6% | 18 Jun, 2024 |
| 6 | Magda Marquet | Director | 3,131 | 0 | 3,131 | 0.1% | 18 Jun, 2024 |
| 7 | Edward W Holmes | Director | 3,131 | 0 | 3,131 | 0.1% | 18 Jun, 2024 |
| 8 | John Markels | Director | 3,131 | 0 | 3,131 | 0.1% | 18 Jun, 2024 |
| 9 | Jing L. Marantz | Director | 3,131 | 0 | 3,131 | 0.1% | 18 Jun, 2024 |
| 10 | Keith C Kummerfeld | Officer | 950 | 0 | 950 | 0.0% | 18 Jul, 2023 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 05 Jun, 2026 | John Markels | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 05 Jun, 2026 | Peter C Farrell | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 05 Jun, 2026 | Jing L. Marantz | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 05 Jun, 2026 | Edward W Holmes | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 05 Jun, 2026 | Magda Marquet | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 05 Jun, 2026 | Moncef Slaoui | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 05 Jun, 2026 | James F Barlow | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 01 May, 2026 | Dennis Mulroy | Chief Financial Officer | Acquired A | 100,000 | $0.00 | $0 | 100,000 | Direct |
| 17 Dec, 2025 | Pad Chivukula | Chief Scientific Officer Coo | Acquired A | 54,000 | $0.00 | $0 | 54,000 | Direct |
| 17 Dec, 2025 | Joseph E Payne | President And Ceo | Acquired A | 175,000 | $0.00 | $0 | 175,000 | Direct |
| 17 Dec, 2025 | Joseph Roberts | Controller | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 17 Dec, 2025 | Lance Kurata | Chief Legal Officer | Acquired A | 54,000 | $0.00 | $0 | 54,000 | Direct |
| 15 Aug, 2025 | Andy Sassine | Chief Financial Officer | Acquired P | 1,238 | $16.56 | $20.50K | 221,764 | Direct |
| 15 Aug, 2025 | Andy Sassine | Chief Financial Officer | Disposed P | 1,238 | $16.56 | $20.50K | 221,764 | Direct |
| 09 Jun, 2025 | Magda Marquet | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 09 Jun, 2025 | Peter C Farrell | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 09 Jun, 2025 | Jing L. Marantz | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 09 Jun, 2025 | Edward W Holmes | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 09 Jun, 2025 | Moncef Slaoui | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |
| 09 Jun, 2025 | James F Barlow | Director | Acquired A | 15,000 | $0.00 | $0 | 15,000 | Direct |