Lyell Immunopharma, Inc. (LYEL) Insider Trading
Over the last 3 months, LYEL insiders made 0 open-market buys and 14 sales, a net sale of -$246K (SEC Form 4). Over the last 6 months, 23 institutions increased and 10 reduced their position (13F).
Insider Activity
Sentiment
0/100
Buys (3m)
0
Sells (3m)
14
Net (3m)
-$245.5K
Insider trades by month Buys Sells
Jan
Feb
Mar
Jun
Jul
Aug
Context3-month price -16.9%Institutions reducing (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| Aug 25, 2026 | Hill Stephen J.officer: Chief Operating Officer | Sell | 989 | $15.54 |
| Aug 25, 2026 | Lee Gary K.officer: Chief Scientific Officer | Sell | 1,457 | $15.54 |
| Aug 25, 2026 | Seely Lynndirector, officer: President and CEO | Sell | 9,589 | $15.54 |
| Aug 11, 2026 | Lee Gary K.officer: Chief Scientific Officer | Sell | 131 | $14.34 |
| Aug 11, 2026 | Bulis Veronica Sanchezofficer: VP, Corporate Controller | Sell | 621 | $14.34 |
| Aug 11, 2026 | Seely Lynndirector, officer: President and CEO | Sell | 390 | $14.34 |
| Aug 11, 2026 | Hill Stephen J.officer: Chief Operating Officer | Sell | 89 | $14.34 |
| Jul 20, 2026 | Innovative Cellular Therapeutics Holdings Ltd10 percent owner | Sell | 10 | $13.70 |
| Jul 17, 2026 | Innovative Cellular Therapeutics Holdings Ltd10 percent owner | Sell | 10 | $13.73 |
| Jun 15, 2026 | Seely Lynndirector, officer: President and CEO | Sell | 388 | $18.91 |
| Jun 15, 2026 | Bulis Veronica Sanchezofficer: VP, Corporate Controller | Sell | 217 | $18.91 |
| Jun 15, 2026 | Hill Stephen J.officer: Chief Operating Officer | Sell | 89 | $18.92 |
| Jun 15, 2026 | Lee Gary K.officer: Chief Scientific Officer | Sell | 130 | $18.92 |
| Jun 12, 2026 | Bachleda Markdirector | Grant | 9,250 | $13.22 |
| Jun 12, 2026 | NABEL ELIZABETH Gdirector | Grant | 9,250 | $13.22 |
| Jun 12, 2026 | Klausner Richarddirector | Grant | 9,250 | $13.22 |
| Jun 12, 2026 | RIEFLIN WILLIAM JLdirector | Grant | 9,250 | $13.22 |
| Jun 12, 2026 | Ramachandra Sumantdirector | Grant | 9,250 | $13.22 |
| Jun 12, 2026 | FRIEDMAN CATHYdirector | Grant | 9,250 | $13.22 |
| Jun 12, 2026 | BRAWLEY OTIS Wdirector | Grant | 9,250 | $13.22 |
| Jun 11, 2026 | Shook Davidofficer: Chief Medical Officer | Sell | 1,977 | $12.64 |
| Mar 16, 2026 | Shah Smitalofficer: Chief Fin. and Bus. Officer | Grant | 140,000 | $25.50 |
| Mar 9, 2026 | ARCH Venture Partners IX, LLC10 percent owner | Buy | 488,090 | $25.61 |
| Mar 9, 2026 | ARCH Venture Fund XIII, L.P.10 percent owner | Buy | 488,090 | $25.61 |
| Feb 12, 2026 | Seely Lynndirector, officer: President and CEO | Sell | 7,455 | $23.39 |
| Feb 12, 2026 | Lee Gary K.officer: Chief Scientific Officer | Sell | 1,671 | $23.39 |
| Feb 12, 2026 | Hill Stephen J.officer: Chief Operating Officer | Sell | 1,236 | $23.39 |
| Feb 11, 2026 | Hill Stephen J.officer: Chief Operating Officer | Grant | 65,000 | $23.71 |
| Feb 11, 2026 | Hill Stephen J.officer: Chief Operating Officer | Grant | 4,000 | — |
| Feb 11, 2026 | Hill Stephen J.officer: Chief Operating Officer | Sell | 109 | $23.12 |
Source: LYEL SEC Form 4 filings, latest Aug 25, 2026. For informational purposes only — not investment advice.
Institutional activity (13F)
How institutions changed their LYEL positions over the last 6 months (SEC Form 13F).
Increased
23
New positions
20
Reduced
10
Sold out
76
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| ARCH VENTURE MANAGEMENT, LLC | Increased | 3.2M | May 15, 2026 |
| GSK PLC | Unchanged | 1.5M | May 14, 2026 |
| FORESITE CAPITAL MANAGEMENT IV, LLC | Unchanged | 800K | May 15, 2026 |
| ORLAND PROPERTIES LTD | Unchanged | 755K | May 6, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 718K | May 15, 2026 |
| ALMITAS CAPITAL LLC | Unchanged | 578K | May 15, 2026 |
| FORESITE CAPITAL MANAGEMENT V, LLC | Unchanged | 477K | May 15, 2026 |
| MILLENNIUM MANAGEMENT LLC | Increased | 459K | May 15, 2026 |
| CITADEL ADVISORS LLC | Increased | 393K | May 15, 2026 |
| VENBIO PARTNERS LLC | Unchanged | 338K | May 15, 2026 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Increased | 310K | May 15, 2026 |
| ALPHABET INC. | Unchanged | 293K | May 8, 2026 |
| BLACKROCK, INC. | Increased | 192K | May 13, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | Increased | 167K | May 15, 2026 |
| SC CHINA HOLDING LTD | Unchanged | 152K | May 15, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.