As of September 29, 2026, the three largest insider holders of LYEL are Cellular Therapeutics Holdings Ltd Innovative (TenPercentOwner, 2.77Mn shares), Venture Partners Ix, Llc Arch (TenPercentOwner, 1.43Mn shares), Venture Fund Xiii, L.P. Arch (TenPercentOwner, 1.43Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | 2,774,980 | 0 | 2,774,980 | 45.6% | 27 Jul, 2026 |
| 2 | Venture Fund Xiii, L.P. Arch | TenPercentOwner | 0 | 1,426,528 | 1,426,528 | 23.4% | 09 Mar, 2026 |
| 3 | Venture Partners Ix, Llc Arch | TenPercentOwner | 0 | 1,426,528 | 1,426,528 | 23.4% | 09 Mar, 2026 |
| 4 | Hans Edgar Bishop | Director | 234,281 | 0 | 234,281 | 3.9% | 09 Sep, 2022 |
| 5 | Lynn Seely | President And Ceo | 63,899 | 0 | 63,899 | 1.1% | 25 Aug, 2026 |
| 6 | Richard Klausner | Director | 0 | 42,168 | 42,168 | 0.7% | 18 Mar, 2025 |
| 7 | David Shook | Chief Medical Officer | 20,423 | 0 | 20,423 | 0.3% | 10 Sep, 2026 |
| 8 | Stephen J. Hill | Chief Operating Officer | 16,816 | 0 | 16,816 | 0.3% | 25 Aug, 2026 |
| 9 | Gary K. Lee | Chief Scientific Officer | 16,220 | 0 | 16,220 | 0.3% | 25 Aug, 2026 |
| 10 | Charles W. Newton | Chief Financial Officer | 15,306 | 0 | 15,306 | 0.3% | 22 Aug, 2025 |
| 11 | Veronica Sanchez Bulis | Vp, Corporate Controller | 14,799 | 0 | 14,799 | 0.2% | 11 Aug, 2026 |
| 12 | Cathy Friedman | Director | 0 | 11,819 | 11,819 | 0.2% | 14 Dec, 2021 |
| 13 | Sumant Ramachandra | Director | 0 | 10,000 | 10,000 | 0.2% | 25 Mar, 2025 |
| 14 | Matthew Lang | Chief Business Officer | 8,125 | 0 | 8,125 | 0.1% | 26 Feb, 2025 |
| 15 | Otis W Brawley | Director | 1,782 | 0 | 1,782 | 0.0% | 02 Apr, 2025 |
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 |
|---|---|---|---|---|---|---|---|---|
| 10 Sep, 2026 | David Shook | Chief Medical Officer | Disposed S | 500 | $12.70 | $6.35K | 20,423 | Direct |
| 10 Sep, 2026 | Jarrad Mattieu Aguirre | Chief Medical Officer | Acquired A | 47,500 | $0.00 | $0 | 47,500 | Direct |
| 21 Aug, 2026 | Lynn Seely | President And Ceo | Disposed S | 9,589 | $15.54 | $149.01K | 63,899 | Direct |
| 21 Aug, 2026 | Stephen J. Hill | Chief Operating Officer | Disposed S | 989 | $15.54 | $15.37K | 16,816 | Direct |
| 21 Aug, 2026 | Gary K. Lee | Chief Scientific Officer | Disposed S | 1,457 | $15.54 | $22.64K | 16,220 | Direct |
| 10 Aug, 2026 | Stephen J. Hill | Chief Operating Officer | Disposed S | 89 | $14.34 | $1.28K | 17,805 | Direct |
| 10 Aug, 2026 | Gary K. Lee | Chief Scientific Officer | Disposed S | 131 | $14.34 | $1.88K | 17,677 | Direct |
| 10 Aug, 2026 | Lynn Seely | President And Ceo | Disposed S | 390 | $14.34 | $5.59K | 73,488 | Direct |
| 10 Aug, 2026 | Veronica Sanchez Bulis | Vp, Corporate Controller | Disposed S | 621 | $14.34 | $8.91K | 14,799 | Direct |
| 27 Jul, 2026 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | Disposed J | 38,500 | $0.00 | $0 | 2,818,980 | Direct |
| 27 Jul, 2026 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | Disposed J | 44,000 | $0.00 | $0 | 2,774,980 | Direct |
| 17 Jul, 2026 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | Disposed S | 10 | $13.70 | $137 | 2,857,480 | Direct |
| 16 Jul, 2026 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | Disposed S | 10 | $13.73 | $137 | 2,857,490 | Direct |
| 29 Jun, 2026 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | Disposed J | 76,000 | $0.00 | $0 | 2,857,500 | Direct |
| 15 Jun, 2026 | Cellular Therapeutics Holdings Ltd Innovative | TenPercentOwner | Disposed J | 66,500 | $0.00 | $0 | 2,933,500 | Direct |
| 11 May, 2026 | Lynn Seely | President And Ceo | Disposed S | 388 | $18.91 | $7.34K | 73,878 | Direct |
| 11 May, 2026 | Gary K. Lee | Chief Scientific Officer | Disposed S | 130 | $18.92 | $2.46K | 17,808 | Direct |
| 11 May, 2026 | Stephen J. Hill | Chief Operating Officer | Disposed S | 89 | $18.92 | $1.68K | 17,894 | Direct |
| 11 May, 2026 | Veronica Sanchez Bulis | Vp, Corporate Controller | Disposed S | 217 | $18.91 | $4.10K | 15,420 | Direct |
| 10 Jun, 2026 | William Jl Rieflin | Director | Acquired A | 9,250 | $0.00 | $0 | 9,250 | Direct |