Institutional Ownership
Alector Inc
CUSIP 014442107COMALECQ1 2026
13D / 13G Filings
47
Schedule 13D/13G on record
Beneficial Filers
16
Distinct reporting persons
Largest Stake
15.3%
Max % of class reported
Institutional Holders
133
13F filers (latest quarter)
Beneficial Owners — Schedule 13D / 13G
47 filings · latest Feb 17, 2026
| # | Filed | Reporting Person | Form | % of Class | Shares | Filing |
|---|---|---|---|---|---|---|
| 1 | Feb 17, 2026 | Rtw Investments, LP | 13G/A | — | 459 | SEC |
| 2 | Feb 6, 2026 | Arnon Rosenthal | 13G/A | 7.4% | 8.21M | SEC |
| 3 | Jan 30, 2026 | The Vanguard Group | 13G/A | 6.3% | 6.91M | SEC |
| 4 | Jan 21, 2026 | Blackrock, Inc. | 13G/A | 4.7% | 5.18M | SEC |
| 5 | Nov 14, 2025 | Rtw Investments, LP | 13G | 6.9% | 6.99M | SEC |
| 6 | Nov 14, 2025 | Tcg Crossover Gp II, LLC | 13G | 9.2% | 10.00M | SEC |
| 7 | Nov 13, 2025 | Polaris Venture Partners Vi, L.P. | 13G/A | 11.0% | 7.10M | SEC |
| 8 | Nov 7, 2025 | Fmr LLC | 13G/A | 3.6% | 3.60M | SEC |
| 9 | Oct 17, 2025 | Blackrock, Inc. | 13G/A | 5.1% | 5.20M | SEC |
| 10 | Aug 14, 2025 | Ra Capital Management, L.P. | 13G/A | — | 913.30M | SEC |
37 more beneficial-ownership filings on Premium
See the full Schedule 13D/13G history for Alector Inc.
Unlock full historyTop Institutional Holders (13F)
Largest reported positions · latest quarter
| # | Fund | Shares | Value |
|---|---|---|---|
| 1 | Tcg Crossover Management, LLC | 10.00M | $21.50M |
| 2 | Blackrock, Inc. | 7.74M | $16.64M |
| 3 | Foresite Capital Management IV, LLC | 3.89M | $8.36M |
| 4 | Merck & Co., Inc. | 3.55M | $7.62M |
| 5 | D. E. Shaw & Co., Inc. | 3.33M | $7.17M |
| 6 | 683 Capital Management, LLC | 3.20M | $6.88M |
| 7 | Balyasny Asset Management L.P. | 2.94M | $6.31M |
| 8 | Nantahala Capital Management, LLC | 2.82M | $6.05M |
| 9 | Geode Capital Management, LLC | 2.29M | $4.92M |
| 10 | Jacobs Levy Equity Management, Inc | 2.15M | $4.63M |