Alector
Develops brain-penetrant therapies for neurodegenerative disease through its ABC delivery platform.
$2.34
After-hours close+0.01 (+0.43%)
At close$2.33(−2.51%)
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Breakdown13F · Form 4
Institutions 79.62%88.40M sharesInsiders 5.32%5.91M sharesOther 15.06%16.72M shares
Shares outstanding 111.03M · Float 77.73M · 70.0% free float
Institutions13F, as of Mar 31, 2026
141 holders · 88.40M shares · 29 new positions · 74 increased · 35 reduced · 22 closed
| Holder | Shares | % outstanding | Chg q/q | Filed |
|---|---|---|---|---|
| TCG Crossover Management, LLC | 10.00M | 9.01% | 0 | May 15, 2026 |
| BlackRock, Inc. | 7.74M | 6.97% | +593.5K | May 13, 2026 |
| Acadian Asset Management LLC | 4.04M | 3.64% | +596.3K | May 13, 2026 |
| Foresite Capital Management Iv, LLC | 3.89M | 3.50% | 0 | May 15, 2026 |
| Vanguard Capital Management LLC | 3.68M | 3.31% | +3.68Mnew | May 15, 2026 |
| Merck & Co., Inc. | 3.55M | 3.19% | 0 | May 13, 2026 |
| D. E. Shaw & Co., Inc. | 3.33M | 3.00% | +967.7K | May 15, 2026 |
| 683 Capital Management, LLC | 3.20M | 2.88% | −150.0K | May 15, 2026 |
Beneficial owners13D/G · 5% or more, as filed
| Holder | % of class | Shares | Form | Filed |
|---|---|---|---|---|
| RA Capital Management, L.P.incl. Rajeev Shah, RA Capital Healthcare Fund, L.P. +1 more | 9.90% | 9.70M | 13G | Dec 6, 2024 ↗ |
| Arnon Rosenthal | 7.40% | 8.21M | 13G | Feb 6, 2026 ↗ |
| BlackRock, Inc. | 5.20% | 5.78M | 13G | Apr 27, 2026 ↗ |
InsidersForm 4
| Insider | Role | Shares | % outstanding | Filed |
|---|---|---|---|---|
| Arnon Rosenthal | director, officer: Chief Executive Officer | 3.46M | 3.11% | Aug 21, 2026 |
| Sara Kenkare-Mitra | officer: President and Head of R&D | 501.7K | 0.45% | Dec 3, 2025 |
| Neil Lindsay Berkley | officer: CFO & Chief Business Officer | 399.3K | 0.36% | Mar 13, 2026 |
| Gary Romano | officer: Chief Medical Officer | 333.0K | 0.30% | Mar 5, 2025 |
| Marc Grasso | officer: Chief Financial Officer | 296.1K | 0.27% | Jun 4, 2025 |
| Richard H. Scheller | director | 134.9K | 0.12% | Jun 17, 2026 |
| Louis J. Jr Lavigne | director | 128.1K | 0.12% | Jun 17, 2026 |
| Kristine Yaffe | director | 124.1K | 0.11% | Jun 17, 2026 |
| Elizabeth A. Garofalo | director | 118.7K | 0.11% | Jun 17, 2026 |
| Grace Wong-Sarad | officer: Principal Accounting Officer | 115.5K | 0.10% | Jul 9, 2026 |
1 ten-percent owner holds 1.91M shares by Form 4, outside the officers-and-directors figure above · 9 people have not refiled in the last 18 months (15.25M shares), so they are not in the figure above
Latest trades
| Date | Insider | Type | Shares | Avg price | Owned after |
|---|---|---|---|---|---|
| Apr 16, 2026 | Grace Wong-Saradofficer: Principal Accounting Officer | Sale | 1,820 | $2.65 | 104,645 |
| Mar 10, 2026 | Grace Wong-Saradofficer: Principal Accounting Officer | Sale | 1,000 | $2.65 | 106,465 |
| Mar 2, 2026 | Neil Lindsay Berkleyofficer: CFO & Chief Business Officer | Sale | 29,649 | $2.12 | 344,660 |
| Mar 2, 2026 | Arnon Rosenthaldirector, officer: Chief Executive Officer | Sale | 81,864 | $2.12 | 2,338,176 |
| Mar 2, 2026 | Grace Wong-Saradofficer: Principal Accounting Officer | Sale | 8,071 | $2.12 | 110,832 |
| Mar 3, 2026 | Grace Wong-Saradofficer: Principal Accounting Officer | Sale | 3,367 | $2.08 | 107,465 |
| Feb 26, 2026 | Grace Wong-Saradofficer: Principal Accounting Officer | Sale | 4,079 | $2.50 | 118,903 |
| Dec 5, 2025 | Grace Wong-Saradofficer: Principal Accounting Officer | Sale | 4,753 | $1.21 | 122,982 |
| Dec 3, 2025 | Neil Lindsay Berkleyofficer: Chief Bus Ofcr & Interim CFO | Sale | 37,261 | $1.12 | 374,309 |
| Dec 3, 2025 | Sara Kenkare-Mitraofficer: President and Head of R&D | Sale | 41,687 | $1.12 | 501,652 |
CongressHouse and Senate disclosures
Not reported.