ALECTOR INC (ALEC)
Institutional ownership reported to the SEC as of Q2 2026, across 31 quarters.
Institutions report 95,850,432 shares against 111,656,919 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. A figure this high can overstate: where an adviser and a sub-adviser both report the same shares, both are counted.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| TCG Crossover Management, LLC | $20.1M | 10,000,000 | 0.48% | 3q | HELD |
| Nantahala Capital Management, LLC | $17.4M | 8,636,218 | 0.29% | 2q | +206.7%+$11.7M |
| BlackRock, Inc. | $15.8M | 7,847,879 | 0.00% | 8q | +1.4%+$214.3K |
| ACADIAN ASSET MANAGEMENT LLC | $8.9M | 4,414,345 | 0.01% | 19q | +9.3%+$754.0K |
| VANGUARD CAPITAL MANAGEMENT LLC | $8.1M | 4,009,340 | 0.00% | 2q | +9.0%+$664.5K |
| Kynam Capital Management, LP | $7.7M | 3,808,494 | 0.42% | 3q | +90.4%+$3.6M |
| Balyasny Asset Management L.P. | $7.5M incl. $1.0M options CALL | 3,247,426 | 0.01% | 3q | +10.6%+$724.8K |
| Merck & Co., Inc. | $7.1M | 3,545,719 | 1.35% | 7q | HELD |
| 683 Capital Management, LLC | $6.4M | 3,200,000 | 0.32% | 4q | HELD |
| D. E. Shaw & Co., Inc. | $5.9M | 2,959,983 | 0.00% | 13q | -11.2%-$749.4K |
| ADAR1 Capital Management, LLC | $5.8M | 2,883,583 | 0.27% | 3q | +174.6%+$3.7M |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $5.7M | 2,820,493 | 0.00% | 2q | +9.2%+$476.3K |
| GEODE CAPITAL MANAGEMENT, LLC | $4.9M | 2,454,271 | 0.00% | 30q | +7.4%+$337.9K |
| Spruce Street Capital LP | $4.2M | 2,101,068 | 0.83% | 3q | HELD |
| MILLENNIUM MANAGEMENT LLC | $4.0M | 1,988,835 | 0.00% | 30q | HELD |
| Ikarian Capital, LLC | $4.0M | 1,982,606 | 0.43% | 7q | -4.8%-$201.0K |
| STATE STREET CORP | $3.8M | 1,879,765 | 0.00% | 30q | +0.8%+$28.6K |
| JACOBS LEVY EQUITY MANAGEMENT, INC | $3.5M | 1,765,929 | 0.01% | 16q | -18.0%-$780.7K |
| MEDICI CAPITAL LLC | $3.3M | 1,652,520 | 6.51% | 15q | HELD |
| Affinity Asset Advisors, LLC | $3.0M | 1,510,000 | 0.14% | 2q | +202.0%+$2.0M |
| Eversept Partners, LP | $2.9M | 1,423,873 | 0.15% | 10q | +5.4%+$146.3K |
| FMR LLC | $2.8M | 1,396,398 | 0.00% | 30q | -22.3%-$803.4K |
| AQR CAPITAL MANAGEMENT LLC | $2.6M | 1,309,577 | 0.00% | 20q | +84.1%+$1.2M |
| Euclidean Capital LLC | $2.6M | 1,307,858 | 0.60% | 23q | HELD |
| MACKENZIE FINANCIAL CORP | $2.2M | 1,109,770 | 0.00% | 5q | +29.4%+$507.4K |
| DEUTSCHE BANK AG\ | $2.2M | 1,098,388 | 0.00% | 30q | +0.5%+$11.0K |
| DEERFIELD MANAGEMENT COMPANY, L.P. | $2.1M | 1,055,192 | 0.02% | 30q | HELD |
| TWO SIGMA INVESTMENTS, LP | $2.1M | 1,045,376 | 0.00% | 20q | -18.3%-$470.2K |
| RENAISSANCE TECHNOLOGIES LLC | $1.9M | 935,166 | 0.00% | 19q | -27.4%-$708.6K |
| DAFNA Capital Management LLC | $1.8M | 908,351 | 0.35% | 20q | HELD |
| Elmind Capital, LP | $1.8M | 900,000 | 0.45% | 3q | HELD |
| PANAGORA ASSET MANAGEMENT INC | $1.7M | 845,999 | 0.01% | 19q | +43.3%+$513.8K |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $1.6M | 818,831 | 0.00% | 30q | +4.0%+$63.2K |
| NORTHERN TRUST CORP | $1.6M | 773,462 | 0.00% | 30q | +11.7%+$163.2K |
| VANGUARD FIDUCIARY TRUST CO | $1.3M | 663,592 | 0.00% | 2q | +14.8%+$172.2K |
| MARSHALL WACE, LLP | $1.2M | 598,559 | 0.00% | 4q | -3.5%-$43.9K |
| CANTOR FITZGERALD, L. P. | $1.2M | 590,984 | 0.01% | new | NEW |
| BOOTHBAY FUND MANAGEMENT, LLC | $1.1M | 532,850 | 0.01% | 10q | -4.8%-$54.0K |
| CITADEL ADVISORS LLC | $1.0M incl. $218.9K options PUT | 391,232 | 0.00% | 26q | +404.5%+$806.0K |
| GOLDMAN SACHS GROUP INC | $872.1K | 433,875 | 0.00% | 30q | -28.2%-$343.1K |
| XTX Topco Ltd | $803.4K | 399,681 | 0.01% | 13q | -28.6%-$322.0K |
| UBS Group AG | $550.3K | 273,780 | 0.00% | 30q | +88.4%+$258.2K |
| Invesco Ltd. | $516.8K | 257,139 | 0.00% | 22q | -3.0%-$15.9K |
| Bank of New York Mellon Corp | $502.7K | 250,093 | 0.00% | 30q | -0.9%-$4.4K |
| AMERIPRISE FINANCIAL INC | $451.3K | 224,530 | 0.00% | 26q | -17.2%-$94.0K |
| NANO CAP NEW MILLENNIUM GROWTH FUND L P | $402.0K | 200,000 | 0.31% | 3q | HELD |
| LMR Partners LLP | $402.0K | 200,000 | 0.00% | new | NEW |
| Nuveen, LLC | $354.2K | 176,234 | 0.00% | 6q | +13.8%+$42.8K |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $346.6K incl. $298.1K options CALL+PUT | 24,123 | 0.00% | 26q | -77.6%-$1.2M |
| Utah Retirement Systems | $310.1K | 154,290 | 0.00% | 19q | HELD |
| BANK OF AMERICA CORP /DE/ | $286.8K | 142,678 | 0.00% | 30q | -62.5%-$478.8K |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | $286.4K | 142,500 | 0.01% | 5q | HELD |
| CANADA PENSION PLAN INVESTMENT BOARD | $263.9K | 131,300 | 0.00% | 3q | -28.3%-$104.3K |
| MORGAN STANLEY | $242.2K | 120,480 | 0.00% | 30q | -67.0%-$490.6K |
| JANE STREET GROUP, LLC | $241.4K CALL | options only | 0.00% | 13q | OPTIONS |
| PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO | $240.7K | 119,769 | 0.00% | 5q | -11.9%-$32.6K |
| ALLIANCEBERNSTEIN L.P. | $234.2K | 108,940 | 0.00% | 29q | +17.2%+$34.4K |
| SIMPLEX TRADING, LLC | $233.9K incl. $62.1K options CALL+PUT | 85,488 | 0.00% | 4q | +24.8%+$46.6K |
| RHUMBLINE ADVISERS | $220.1K | 109,532 | 0.00% | 29q | +8.1%+$16.5K |
| STRS OHIO | $204.2K | 101,600 | 0.00% | 20q | +17.5%+$30.4K |
| Russell Investments Group, Ltd. | $198.0K | 98,496 | 0.00% | 19q | +48.9%+$65.1K |
| WELLS FARGO & COMPANY/MN | $179.2K | 89,172 | 0.00% | 30q | +158.3%+$109.8K |
| PRICE T ROWE ASSOCIATES INC /MD/ | $165.0K | 81,655 | 0.00% | 26q | +45.6%+$51.6K |
| Blackstone Inc. | $155.1K | 77,145 | 0.00% | 15q | HELD |
| Jasper Ridge Partners, L.P. | $147.8K | 73,531 | 0.00% | 12q | HELD |
| SEI INVESTMENTS CO | $143.0K | 71,151 | 0.00% | 6q | +32.1%+$34.8K |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main | $140.0K | 69,666 | 0.00% | 2q | HELD |
| IEQ CAPITAL, LLC | $121.7K | 60,570 | 0.00% | 2q | +28.7%+$27.1K |
| Verdad Advisers, LP | $121.6K | 60,509 | 0.12% | 2q | +156.9%+$74.3K |
| MetLife Investment Management, LLC | $118.0K | 58,696 | 0.00% | 2q | +62.1%+$45.2K |
| Mariner, LLC | $106.0K | 52,709 | 0.00% | 2q | +180.4%+$68.2K |
| Vanguard Personalized Indexing Management, LLC | $99.4K | 49,445 | 0.00% | 7q | -2.3%-$2.4K |
| HSBC HOLDINGS PLC | $98.0K | 48,523 | 0.00% | 17q | HELD |
| Graham Capital Management, L.P. | $93.5K | 46,496 | 0.00% | new | NEW |
| CITIGROUP INC | $93.0K | 46,275 | 0.00% | 30q | +897.5%+$83.7K |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | $90.8K | 45,190 | 0.00% | 9q | +5.9%+$5.1K |
| BARCLAYS PLC | $90.4K | 44,957 | 0.00% | 30q | +5.6%+$4.8K |
| JPMORGAN CHASE & CO | $89.4K | 42,998 | 0.00% | 30q | +15.0%+$11.7K |
| DIVERSIFIED TRUST CO | $85.1K | 42,351 | 0.00% | 14q | +63.5%+$33.1K |
| DIMENSIONAL FUND ADVISORS LP | $68.0K | 33,728 | 0.00% | 15q | -88.1%-$504.5K |
| Cerity Partners LLC | $65.4K | 32,521 | 0.00% | 6q | +20.6%+$11.1K |
| Vanguard Global Advisers, LLC | $62.9K | 31,302 | 0.00% | 2q | HELD |
| Cannell & Spears LLC | $61.0K | 30,342 | 0.00% | 10q | -44.5%-$48.8K |
| Vontobel Holding Ltd. | $60.3K | 30,000 | 0.00% | 12q | HELD |
| Point72 Asset Management, L.P. | $53.7K | 26,699 | 0.00% | 4q | -66.7%-$107.3K |
| ROYAL BANK OF CANADA | $53.0K | 26,122 | 0.00% | 27q | +270.7%+$38.7K |
| GROUP ONE TRADING LLC | $51.7K incl. $1.0K options CALL | 25,208 | 0.00% | new | NEW |
| MERCER GLOBAL ADVISORS INC /ADV | $51.3K | 25,504 | 0.00% | new | NEW |
| INTECH INVESTMENT MANAGEMENT LLC | $49.3K | 24,530 | 0.00% | 8q | +2.4%+$1.2K |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC | $48.7K | 30,251 | 0.00% | 2q | +66.2%+$19.4K |
| Police & Firemen's Retirement System of New Jersey | $47.1K | 23,426 | 0.00% | 7q | HELD |
| VOYA INVESTMENT MANAGEMENT LLC | $44.0K | 21,898 | 0.00% | 28q | +41.5%+$12.9K |
| BNP PARIBAS FINANCIAL MARKETS | $42.6K | 21,200 | 0.00% | 29q | +5.9%+$2.4K |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | $39.0K | 19,397 | 0.00% | 28q | -25.8%-$13.6K |
| Qube Research & Technologies Ltd | $33.3K | 16,569 | 0.00% | new | NEW |
| CAPTRUST FINANCIAL ADVISORS | $32.2K | 16,037 | 0.00% | 2q | +50.6%+$10.8K |
| PRUDENTIAL FINANCIAL INC | $32.2K | 16,015 | 0.00% | 5q | -32.7%-$15.6K |
| Creative Planning | $30.2K | 15,015 | 0.00% | new | NEW |
| Tower Research Capital LLC (TRC) | $29.0K | 14,450 | 0.00% | 25q | +143.1%+$17.1K |
| HAMILTON LANE ADVISORS LLC | $28.9K | 14,400 | 0.02% | 2q | HELD |
Five percent filings
Anyone crossing 5% of a company must say so within days - far sooner than the next quarterly holdings report. A 13D declares an intent to influence the company; a 13G is the passive version. See all activist filings →
| Filed | Form | Filer | % of class |
|---|---|---|---|
| 2026-10-26 | 13G | RA Capital Management, L.P.with 3 co-filers | 5.1% |
| 2026-10-23 | 13G | Deep Track Capital, LPwith 2 co-filers | 8.6% |
| 2026-09-18 | 13G | BVF PARTNERS L P/ILwith 9 co-filers | 8.4% |
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-10-16 | 2026-10-15 | Material agreement entered | filing |
| 2026-10-14 | 2026-10-13 | Directors or officers departed or appointed | filing |
| 2026-10-05 | 2026-09-30 | Material agreement entered | filing |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Officers and directors
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-09-03 | Rosenthal Arnon | Chief Executive Officer | Sold | 72,606 | $193.5K |
| 2026-06-02 | Rosenthal Arnon | Chief Executive Officer | Sold | 87,216 | $172.2K |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 17 | $47.4K | 25,544 | 3 | 6 | 6 | 0.0% |
| Q2 2026 | 141 | $194.5M | 95,850,432 | 13 | 58 | 36 | 0.9% |
| Q1 2026 | 139 | $190.7M | 88,395,948 | 25 | 43 | 36 | 0.4% |
| Q4 2025 | 132 | $133.4M | 84,505,478 | 21 | 41 | 39 | 0.8% |
| Q3 2025 | 149 | $224.4M | 74,879,140 | 27 | 44 | 41 | 1.2% |
| Q2 2025 | 137 | $99.5M | 70,872,080 | 16 | 47 | 36 | 0.2% |
| Q1 2025 | 141 | $90.3M | 72,635,086 | 19 | 43 | 32 | 0.5% |
| Q4 2024 | 151 | $139.3M | 73,449,380 | 24 | 46 | 37 | 0.4% |
| Q3 2024 | 160 | $352.2M | 75,276,399 | 18 | 47 | 49 | 0.3% |
| Q2 2024 | 162 | $338.3M | 74,444,446 | 23 | 57 | 49 | 0.1% |
| Q1 2024 | 158 | $497.2M | 82,525,801 | 28 | 59 | 35 | 0.1% |
| Q4 2023 | 150 | $563.3M | 70,442,663 | 13 | 47 | 46 | 0.2% |
| Q3 2023 | 148 | $411.8M | 63,428,057 | 19 | 55 | 39 | 0.2% |
| Q2 2023 | 146 | $354.8M | 58,985,788 | 14 | 52 | 38 | 0.1% |
| Q1 2023 | 151 | $401.5M | 64,766,819 | 13 | 54 | 40 | 0.1% |
| Q4 2022 | 155 | $510.6M | 54,820,123 | 18 | 50 | 51 | 0.9% |
| Q3 2022 | 155 | $726.9M | 76,392,869 | 27 | 57 | 38 | 0.6% |
| Q2 2022 | 143 | $773.6M | 75,747,987 | 11 | 50 | 45 | 0.4% |
| Q1 2022 | 156 | $1.2B | 82,059,870 | 18 | 54 | 48 | 0.4% |
| Q4 2021 | 160 | $1.6B | 75,012,340 | 32 | 49 | 38 | 0.6% |
| Q3 2021 | 142 | $1.6B | 67,450,436 | 25 | 54 | 25 | 0.8% |
| Q2 2021 | 132 | $1.3B | 64,277,690 | 28 | 48 | 28 | 0.7% |
| Q1 2021 | 121 | $1.2B | 59,839,370 | 14 | 27 | 43 | 0.4% |
| Q4 2020 | 130 | $1.0B | 66,612,118 | 12 | 37 | 49 | 1.0% |
| Q3 2020 | 136 | $739.9M | 69,770,185 | 34 | 42 | 34 | 0.6% |
| Q2 2020 | 134 | $1.6B | 64,473,447 | 40 | 46 | 31 | 0.5% |
| Q1 2020 | 107 | $1.8B | 72,712,903 | 38 | 36 | 26 | 0.2% |
| Q4 2019 | 80 | $812.4M | 47,150,503 | 15 | 34 | 14 | 0.0% |
| Q3 2019 | 74 | $12.3B | 855,300,884 | 17 | 34 | 12 | 0.0% |
| Q2 2019 | 62 | $10.7B | 579,552,297 | 13 | 19 | 12 | 0.0% |
| Q1 2019 | 54 | $526.0M | 28,731,149 | 54 | 0 | 0 | 0.0% |
