Cel Sci's top three insider shareholders as of September 29, 2026 are Geert R Kersten (Chief Executive Officer, 316.14K shares), Geert R Kersten (Chief Executive Officer, 311.55K shares), Patricia B Prichep (Chief Financial Officer, 17.49K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Geert R Kersten | Chief Executive Officer | 316,142 | 0 | 316,142 | 91.2% | 26 Aug, 2026 |
| 2 | Patricia B Prichep | Chief Financial Officer | 17,489 | 0 | 17,489 | 5.0% | 01 Jul, 2026 |
| 3 | Eyal Talor | Chief Scientific Officer | 9,318 | 0 | 9,318 | 2.7% | 01 Jul, 2026 |
| 4 | Robert Eugene Watson | Director | 3,733 | 0 | 3,733 | 1.1% | 29 Jul, 2025 |
| 5 | Daniel H Zimmerman | Senior Vice President | 16 | 0 | 16 | 0.0% | 03 Oct, 2022 |
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 |
|---|---|---|---|---|---|---|---|---|
| 25 Aug, 2026 | Geert R Kersten | Chief Executive Officer | Acquired P | 100,000 | $1.38 | $138.00K | 316,142 | Direct |
| 14 Aug, 2026 | Robert Eugene Watson | Director | Acquired A | 110,000 | $0.01 | $1.10K | 137,271 | Direct |
| 14 Aug, 2026 | Eyal Talor | Chief Scientific Officer | Acquired A | 250,000 | $0.01 | $2.50K | 331,625 | Direct |
| 14 Aug, 2026 | John Cipriano | Senior Vice President | Acquired A | 80,000 | $0.01 | $800 | 118,010 | Direct |
| 14 Aug, 2026 | Geert R Kersten | Chief Executive Officer | Acquired A | 300,000 | $0.01 | $3.00K | 452,380 | Direct |
| 14 Aug, 2026 | Bruno Jean-Marie Baillavoine | Director | Acquired A | 110,000 | $0.01 | $1.10K | 138,021 | Direct |
| 30 Jun, 2026 | Eyal Talor | Chief Scientific Officer | Acquired A | 2,307 | $1.04 | $2.40K | 9,318 | Direct |
| 30 Jun, 2026 | Geert R Kersten | Chief Executive Officer | Acquired A | 5,192 | $1.04 | $5.40K | 216,142 | Direct |
| 30 Jun, 2026 | Patricia B Prichep | Chief Financial Officer | Acquired A | 4,125 | $1.04 | $4.29K | 17,489 | Direct |
| 14 May, 2026 | Geert R Kersten | Chief Executive Officer | Acquired P | 300,000 | $1.20 | $360.00K | 311,547 | Indirect |
| 13 May, 2026 | Geert R Kersten | Chief Executive Officer | Acquired P | 100,000 | $1.19 | $119.00K | 222,497 | Direct |
| 31 Mar, 2026 | Geert R Kersten | Chief Executive Officer | Acquired A | 1,682 | $3.21 | $5.40K | 122,497 | Direct |
| 31 Mar, 2026 | Eyal Talor | Chief Scientific Officer | Acquired A | 747 | $3.21 | $2.40K | 7,011 | Direct |
| 31 Mar, 2026 | Patricia B Prichep | Chief Financial Officer | Acquired A | 1,336 | $3.21 | $4.29K | 13,364 | Direct |
| 22 Jan, 2026 | Geert R Kersten | Chief Executive Officer | Acquired P | 38,023 | $5.26 | $200.00K | 120,815 | Direct |
| 31 Dec, 2025 | Geert R Kersten | Chief Executive Officer | Acquired A | 998 | $5.26 | $5.25K | 82,792 | Direct |
| 31 Dec, 2025 | Patricia B Prichep | Chief Financial Officer | Acquired A | 815 | $5.26 | $4.29K | 12,028 | Direct |
| 31 Dec, 2025 | Eyal Talor | Chief Scientific Officer | Acquired A | 456 | $5.26 | $2.40K | 6,264 | Direct |
| 04 Dec, 2025 | Geert R Kersten | Chief Executive Officer | Acquired P | 8,389 | $5.96 | $50.00K | 81,794 | Direct |
| 30 Sep, 2025 | Patricia B Prichep | Chief Financial Officer | Acquired A | 466 | $9.20 | $4.29K | 11,213 | Direct |