ALEC · Alector, Inc. · Holdings
Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.
Institutional Ownership Trend
Holder Concentration
Across 141 13F filersWho Holds ALEC
Last 8 quarters through Sep 30, 2026 (filing window open)Each kind of 13F filer's share of the common shares 13F filers report. Holder type comes from regulatory records, never the filer's name; style, turnover and horizon are measured from each filer's own 13F book. The quarter selector does not change this card.
Jun 30, 2026, the newest closed quarter: 140 filers, like-for-like change +3.2%; actively managed books +3.6%; index-like books +2.0%.
| Holder type | Share | Filers | Change |
|---|---|---|---|
| Registered adviser | 55.0% | 71 | +17.2% |
| Exempt adviser | 0.9% | 3 | +31.4% |
| Adviser | 0.6% | 3 | -8.9% |
| Bank | 3.9% | 12 | +3.1% |
| Insurer | 0.0% | 1 | -32.7% |
| Broker-dealer | 0.0% | 1 | new |
| Benefit plan | 0.2% | 3 | -2.1% |
| Non-US | 1.4% | 5 | -3.9% |
| Holding company | 10.8% | 7 | -6.5% |
| Unknown | 27.1% | 34 | -13.9% |
| Style | Share | Filers | Change |
|---|---|---|---|
| Index-like | 21.0% | 20 | +2.0% |
| Systematic-like | 11.7% | 11 | -1.9% |
| Concentrated | 16.3% | 24 | -10.5% |
| Diversified active | 51.0% | 85 | +10.6% |
| Not measured | 0.0% | 0 | — |
| Unknown | 0.0% | 0 | — |
| Turnover | Share | Filers | Change |
|---|---|---|---|
| Low turnover | 28.8% | 76 | -2.5% |
| Medium turnover | 44.5% | 35 | +9.3% |
| High turnover | 14.9% | 19 | -3.6% |
| Unknown | 11.8% | 10 | +5.9% |
| Not measured | 0.0% | 0 | — |
| Holding horizon | Share | Filers | Change |
|---|---|---|---|
| Short horizon | 12.3% | 13 | +3.3% |
| Medium horizon | 34.6% | 25 | +12.0% |
| Long horizon | 37.2% | 91 | -6.9% |
| Unknown | 15.9% | 11 | +12.8% |
| Not measured | 0.0% | 0 | — |
| 13F book size | Share | Filers | Change |
|---|---|---|---|
| Under $1B | 13.9% | 23 | -24.2% |
| $1B to $10B | 32.8% | 29 | +26.9% |
| $10B to $100B | 14.8% | 39 | +5.7% |
| $100B or more | 38.5% | 49 | -0.4% |
| Not measured | 0.0% | 0 | — |
| Client base | Share | Filers | Change |
|---|---|---|---|
| Individuals and high net worth | 0.3% | 24 | +40.9% |
| Pooled investment vehicles | 38.5% | 23 | +21.9% |
| Registered funds and BDCs | 11.4% | 8 | +5.5% |
| Pension and profit sharing plans | 0.0% | 2 | +49.6% |
| Insurance companies | 0.1% | 3 | +48.3% |
| Governments and sovereign funds | 1.0% | 2 | +38.1% |
| Other investment advisers | 0.1% | 2 | -2.3% |
| Other | 0.1% | 1 | -55.0% |
| Diversified | 3.5% | 6 | +7.5% |
| Unknown | 45.0% | 69 | -9.8% |
| Private funds | Share | Filers | Change |
|---|---|---|---|
| Hedge funds | 42.2% | 27 | +20.4% |
| Private equity funds | 0.2% | 5 | +103.1% |
| Venture capital funds | 0.0% | 1 | +183.3% |
| Real estate funds | 0.0% | 3 | +395.4% |
| Other private funds | 1.8% | 12 | +1.4% |
| Mixed private funds | 0.1% | 1 | +17.2% |
| Private funds, type not stated | 0.2% | 1 | new |
| No private funds | 11.3% | 24 | +7.5% |
| Securitized asset funds | 0.0% | 0 | — |
| Unknown | 44.1% | 66 | -10.4% |
| Location | Share | Filers | Change |
|---|---|---|---|
| United States | 95.4% | 116 | +3.0% |
| Outside the US | 4.6% | 24 | +7.7% |
The Sep 30, 2026 filing window is still open, so its bar carries the Jun 30, 2026 positions of filers that have not filed yet.
How the mix is measured
Shares are 13F common shares restated to today's split basis; options and principal amounts are left out. The change compares only filers with a 13F in both quarters and keeps each filer in its bucket of the later quarter on both sides; a filer that continues under a new CIK is compared through its successor. Holder type comes from each filer's current regulatory profile; client base and private funds come from the Form ADV roster current at each quarter end (rosters from December 2019, so an earlier quarter reads Unknown). Style, turnover, horizon and book size are measured from each filer's 13F book in the newest measured quarter, and Not measured means none was. Actively managed books are those measured systematic-like, concentrated or diversified active.
Excluded 2 holders with no observed 2026-06-30 13F.
Conviction and Crowding
140 13F filers, quarter ended Jun 30, 2026Measured across every 13F filer's common-share book once the quarter's filing window closed. Crowding counts filers with high turnover or that advise private funds on Form ADV.
Managers in the top fifth by current three-year FundScore alpha were net buyers of $0 (0 buying, 0 selling).
Estimated Holder Cost Basis
Quarter ended Jun 30, 2026, on that quarter's share basisEstimated, never filed: each 13F buy is costed at its quarter's average traded price and each sale keeps the average cost, so this is what holders paid on average if they traded evenly through each quarter.
Estimated cost covers 57.3% of the 13F shares; positions already held when a filer's 13F history starts, or bought in a quarter without a trusted average price, have no estimate.
Shared Holders
Companies ALEC's active holders also own, quarter ended Jun 30, 2026| # | Company | Shared holders |
|---|---|---|
| 1 | LXEO Lexeo Therapeutics, Inc. | 7 |
| 2 | STRO Sutro Biopharma, Inc. | 5 |
| 3 | PRQR ProQR Therapeutics N.V. | 6 |
| 4 | AMAN Amanat Acquisition Corp. | 4 |
| 5 | IFRX InflaRx N.V. | 5 |
| 6 | BCRX Biocryst Pharmaceuticals Inc | 7 |
| 7 | AMLX Amylyx Pharmaceuticals, Inc. | 7 |
| 8 | EQ Equillium, Inc. | 4 |
| 9 | JATT JATT II Acquisition Corp. | 4 |
| 10 | SVRA Savara Inc | 7 |
Shareholder Targets
13F filers that own its peers but not ALEC, quarter ended Jun 30, 2026Found through its holder-overlap peers: LXEO, STRO, PRQR, AMAN, IFRX, BCRX, AMLX, EQ, JATT, SVRA, TRAX, PLRX, KRRO, SRZN, RLAY, PHVS, JANX, CATX, RACC, AVR. 549 filers in all.
| # | Filer | In peers | Largest peers |
|---|---|---|---|
| 1 | PERCEPTIVE ADVISORS LLC Registered adviser, Diversified active | $614,878,103 7 held | RLAY, AMLX, BCRX |
| 2 | SB INVESTMENT ADVISERS (UK) LTD Registered adviser, Concentrated | $522,101,857 1 held | RLAY |
| 3 | Commodore Capital LP Registered adviser, Concentrated | $418,580,926 6 held | RLAY, AMLX, PHVS |
| 4 | RA CAPITAL MANAGEMENT, L.P. Registered adviser, Concentrated | $402,368,819 7 held | JANX, BCRX, AVR |
| 5 | Casdin Capital, LLC Registered adviser, Concentrated | $300,019,340 1 held | RLAY |
| 6 | Jupiter Topco LLC Unknown, Diversified active | $266,945,525 10 held | BCRX, AMLX, TRAX |
| 7 | GENERAL ATLANTIC, L.P. Unknown, Concentrated | $226,525,177 1 held | PHVS |
| 8 | Bain Capital Life Sciences Investors, LLC Unknown, Concentrated | $200,938,926 2 held | SVRA, PHVS |
| 9 | Foresite Capital Management IV, LLC Unknown, Concentrated | $188,630,830 2 held | PHVS, RLAY |
| 10 | Polar Capital Holdings Plc Registered adviser, Diversified active | $172,697,169 3 held | PHVS, SVRA, RLAY |
Fund Ownership of ALEC by Fund Type
Registered funds' Form N-PORT reports for the quarter ended Jun 30, 2026Index funds and index ETFs hold 11.10% of shares outstanding.
| Fund type | Of shares outstanding | Shares |
|---|---|---|
| Index funds | 2.80% | 3,126,405 |
| Index ETFs | 8.30% | 9,263,273 |
| Active ETFs | 0.06% | 67,665 |
| Active funds | 4.57% | 5,107,579 |
| Unclassified | 0.20% | 228,555 |
| All registered funds | 15.94% | 17,793,477 |
How fund types are measured
Each fund series counts once, with its latest Form N-PORT report dated inside the quarter; only long share positions count, restated to today's split basis. The fund type is the series' latest Form N-CEN answer on or before the quarter end (the index-fund box and the exchange-traded flag), never its name. Unclassified funds have no usable N-CEN; unit investment trusts are among them, so index ownership is a floor. Funds sit inside their advisers' 13F reports, so these shares overlap the 13F figures and are never added to them.
| Holder | Value (USD) | % of 13F | Shares | Type | Filed | Open |
|---|---|---|---|---|---|---|
| Mid TCG Crossover Management, LLC | $20,100,000 | 10.86% | 10,000,000 | Shares | 2026-08-14 | |
| Mega BlackRock, Inc. Holding company | $15,774,232 | 8.53% | 7,847,879 | Shares | 2026-08-07 | |
| Large ACADIAN ASSET MANAGEMENT LLC | $8,872,833 | 4.80% | 4,414,345 | Shares | 2026-08-13 | |
| Mid Nantahala Capital Management, LLC Registered adviser | $8,679,399 | 4.69% | 4,318,109 | Shares | 2026-08-19 | |
| Mega VANGUARD CAPITAL MANAGEMENT LLC Registered adviser | $8,058,773 | 4.36% | 4,009,340 | Shares | 2026-08-13 | |
| Mid Kynam Capital Management, LP Registered adviser | $7,655,072 | 4.14% | 3,808,494 | Shares | 2026-08-14 | |
| Small Merck & Co., Inc. | $7,126,895 | 3.85% | 3,545,719 | Shares | 2026-08-07 | |
| Large Balyasny Asset Management L.P. Registered adviser | $6,527,326 | 3.53% | 3,247,426 | Shares | 2026-08-14 | |
| Mid 683 Capital Management, LLC Registered adviser | $6,432,000 | 3.48% | 3,200,000 | Shares | 2026-08-14 | |
| Mega D. E. Shaw & Co., Inc. | $5,949,565 | 3.22% | 2,959,983 | Shares | 2026-08-14 | |
| Mid ADAR1 Capital Management, LLC Registered adviser | $5,796,001 | 3.13% | 2,883,583 | Shares | 2026-08-14 | |
| Mega VANGUARD PORTFOLIO MANAGEMENT LLC Registered adviser | $5,669,190 | 3.06% | 2,820,493 | Shares | 2026-08-13 | |
| Mega GEODE CAPITAL MANAGEMENT, LLC Registered adviser | $4,933,084 | 2.67% | 2,454,271 | Shares | 2026-08-12 | |
| Small Spruce Street Capital LP Registered adviser | $4,223,146 | 2.28% | 2,101,068 | Shares | 2026-08-13 | |
| Mega MILLENNIUM MANAGEMENT LLC Registered adviser | $3,997,558 | 2.16% | 1,988,835 | Shares | 2026-08-14 | |
| Small Ikarian Capital, LLC Registered adviser | $3,985,038 | 2.15% | 1,982,606 | Shares | 2026-08-14 | |
| Mega STATE STREET CORP Bank | $3,778,327 | 2.04% | 1,879,765 | Shares | 2026-09-22 | |
| Large JACOBS LEVY EQUITY MANAGEMENT, INC Registered adviser | $3,549,517 | 1.92% | 1,765,929 | Shares | 2026-08-14 | |
| Micro MEDICI CAPITAL LLC Registered adviser | $3,321,565 | 1.80% | 1,652,520 | Shares | 2026-08-11 | |
| Mid Affinity Asset Advisors, LLC Registered adviser | $3,035,100 | 1.64% | 1,510,000 | Shares | 2026-08-13 | |
| Mid Eversept Partners, LP Registered adviser | $2,861,984 | 1.55% | 1,423,873 | Shares | 2026-08-14 | |
| Mega FMR LLC Holding company | $2,806,759 | 1.52% | 1,396,398 | Shares | 2026-08-13 | |
| Mega AQR CAPITAL MANAGEMENT LLC Registered adviser | $2,632,247 | 1.42% | 1,309,577 | Shares | 2026-08-14 | |
| Small Euclidean Capital LLC | $2,628,794 | 1.42% | 1,307,858 | Shares | 2026-08-14 | |
| Large MACKENZIE FINANCIAL CORP Registered adviser | $2,230,637 | 1.21% | 1,109,770 | Shares | 2026-08-13 | |
| Mega DEUTSCHE BANK AG\ Non-US | $2,207,759 | 1.19% | 1,098,388 | Shares | 2026-08-07 | |
| Mid DEERFIELD MANAGEMENT COMPANY, L.P. Registered adviser | $2,120,935 | 1.15% | 1,055,192 | Shares | 2026-08-14 | |
| Mega TWO SIGMA INVESTMENTS, LP Registered adviser | $2,101,205 | 1.14% | 1,045,376 | Shares | 2026-08-14 | |
| Large RENAISSANCE TECHNOLOGIES LLC Registered adviser | $1,879,683 | 1.02% | 935,166 | Shares | 2026-08-13 | |
| Small DAFNA Capital Management LLC Registered adviser | $1,825,785 | 0.99% | 908,351 | Shares | 2026-08-14 | |
| Small Elmind Capital, LP Registered adviser | $1,809,000 | 0.98% | 900,000 | Shares | 2026-08-14 | |
| Large PANAGORA ASSET MANAGEMENT INC Registered adviser | $1,700,457 | 0.92% | 845,999 | Shares | 2026-08-06 | |
| Mega CHARLES SCHWAB INVESTMENT MANAGEMENT INC Registered adviser | $1,645,850 | 0.89% | 818,831 | Shares | 2026-08-14 | |
| Mega NORTHERN TRUST CORP Bank | $1,554,657 | 0.84% | 773,462 | Shares | 2026-08-13 | |
| Mega VANGUARD FIDUCIARY TRUST CO | $1,333,819 | 0.72% | 663,592 | Shares | 2026-08-13 | |
| Mega MARSHALL WACE, LLP Exempt adviser | $1,203,102 | 0.65% | 598,559 | Shares | 2026-08-13 | |
| Mid BOOTHBAY FUND MANAGEMENT, LLC Registered adviser | $1,071,028 | 0.58% | 532,850 | Shares | 2026-08-14 | |
| Large Balyasny Asset Management L.P. Registered adviser | $1,012,839 | 0.55% | 503,900 | Call | 2026-08-14 | |
| Mega GOLDMAN SACHS GROUP INC Holding company | $872,088 | 0.47% | 433,875 | Shares | 2026-08-14 | |
| Mid XTX Topco Ltd | $803,358 | 0.43% | 399,681 | Shares | 2026-08-14 | |
| Mega CITADEL ADVISORS LLC Registered adviser | $786,376 | 0.43% | 391,232 | Shares | 2026-09-02 | |
| Mid CANTOR FITZGERALD, L. P. | $593,938 | 0.32% | 295,492 | Shares | 2026-08-19 | |
| Mega UBS Group AG Bank | $550,297 | 0.30% | 273,780 | Shares | 2026-08-13 | |
| Mega Invesco Ltd. Adviser | $516,847 | 0.28% | 257,139 | Shares | 2026-08-14 | |
| Mega Bank of New York Mellon Corp Bank | $502,686 | 0.27% | 250,093 | Shares | 2026-08-06 | |
| Mega AMERIPRISE FINANCIAL INC Adviser | $451,305 | 0.24% | 224,530 | Shares | 2026-08-14 | |
| Large LMR Partners LLP Exempt adviser | $402,000 | 0.22% | 200,000 | Shares | 2026-08-14 | |
| Small NANO CAP NEW MILLENNIUM GROWTH FUND L P | $402,000 | 0.22% | 200,000 | Shares | 2026-08-14 | |
| Mega Nuveen, LLC | $354,230 | 0.19% | 176,234 | Shares | 2026-08-11 | |
| Large Utah Retirement Systems | $310,122 | 0.17% | 154,290 | Shares | 2026-08-14 | |
| Mega BANK OF AMERICA CORP /DE/ Bank | $286,781 | 0.16% | 142,678 | Shares | 2026-08-14 | |
| Mid BRIDGEWAY CAPITAL MANAGEMENT, LLC Registered adviser | $286,425 | 0.15% | 142,500 | Shares | 2026-08-14 | |
| Mega SUSQUEHANNA INTERNATIONAL GROUP, LLP | $273,159 | 0.15% | 135,900 | Call | 2026-08-14 | |
| Mega CANADA PENSION PLAN INVESTMENT BOARD Non-US | $263,913 | 0.14% | 131,300 | Shares | 2026-08-14 | |
| Mega MORGAN STANLEY Holding company | $242,163 | 0.13% | 120,480 | Shares | 2026-08-13 | |
| Mega JANE STREET GROUP, LLC | $241,401 | 0.13% | 120,100 | Call | 2026-08-14 | |
| Large PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO Benefit plan | $240,735 | 0.13% | 119,769 | Shares | 2026-08-17 | |
| Mega RHUMBLINE ADVISERS Registered adviser | $220,159 | 0.12% | 109,532 | Shares | 2026-08-12 | |
| Mega ALLIANCEBERNSTEIN L.P. Registered adviser | $218,969 | 0.12% | 108,940 | Shares | 2026-08-14 | |
| Mega CITADEL ADVISORS LLC Registered adviser | $218,889 | 0.12% | 108,900 | Put | 2026-09-02 | |
| Large STRS OHIO Benefit plan | $204,216 | 0.11% | 101,600 | Shares | 2026-07-30 | |
| Mega Russell Investments Group, Ltd. | $197,973 | 0.11% | 98,496 | Shares | 2026-08-06 | |
| Mega WELLS FARGO & COMPANY/MN Bank | $179,235 | 0.10% | 89,172 | Shares | 2026-08-14 | |
| Mid SIMPLEX TRADING, LLC | $171,830 | 0.09% | 85,488 | Shares | 2026-08-12 | |
| Mega PRICE T ROWE ASSOCIATES INC /MD/ Registered adviser | $164,126 | 0.09% | 81,655 | Shares | 2026-08-14 | |
| Large Blackstone Inc. Adviser | $155,061 | 0.08% | 77,145 | Shares | 2026-08-14 | |
| Mid Jasper Ridge Partners, L.P. Registered adviser | $147,797 | 0.08% | 73,531 | Shares | 2026-08-14 | |
| Mega SEI INVESTMENTS CO Holding company | $143,013 | 0.08% | 71,151 | Shares | 2026-08-14 | |
| Mega DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main | $140,028 | 0.08% | 69,666 | Shares | 2026-08-14 | |
| Large IEQ CAPITAL, LLC Registered adviser | $121,745 | 0.07% | 60,570 | Shares | 2026-08-11 | |
| Small Verdad Advisers, LP | $121,623 | 0.07% | 60,509 | Shares | 2026-08-14 | |
| Large MetLife Investment Management, LLC Registered adviser | $117,978 | 0.06% | 58,696 | Shares | 2026-08-14 | |
| Large Mariner, LLC Registered adviser | $105,945 | 0.06% | 52,709 | Shares | 2026-08-13 | |
| Large Vanguard Personalized Indexing Management, LLC Registered adviser | $99,384 | 0.05% | 49,445 | Shares | 2026-08-11 | |
| Mega HSBC HOLDINGS PLC | $97,531 | 0.05% | 48,523 | Shares | 2026-08-14 | |
| Mid Graham Capital Management, L.P. Registered adviser | $93,456 | 0.05% | 46,496 | Shares | 2026-08-14 | |
| Mega CITIGROUP INC Bank | $93,012 | 0.05% | 46,275 | Shares | 2026-08-03 | |
| Large MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | $90,831 | 0.05% | 45,190 | Shares | 2026-08-14 | |
| Mega BARCLAYS PLC Bank | $90,363 | 0.05% | 44,957 | Shares | 2026-08-14 | |
| Mega JPMORGAN CHASE & CO Bank | $86,425 | 0.05% | 42,998 | Shares | 2026-08-12 | |
| Mid Diversified Trust Co | $85,125 | 0.05% | 42,351 | Shares | 2026-07-17 | |
| Mega DIMENSIONAL FUND ADVISORS LP Registered adviser | $67,792 | 0.04% | 33,728 | Shares | 2026-08-11 | |
| Large Cerity Partners LLC Registered adviser | $65,366 | 0.04% | 32,521 | Shares | 2026-08-14 | |
| Mega Vanguard Global Advisers, LLC Registered adviser | $62,917 | 0.03% | 31,302 | Shares | 2026-08-13 | |
| Mid Cannell & Spears LLC Registered adviser | $60,987 | 0.03% | 30,342 | Shares | 2026-08-11 | |
| Large Point72 Asset Management, L.P. Registered adviser | $53,664 | 0.03% | 26,699 | Shares | 2026-08-14 | |
| Mega ROYAL BANK OF CANADA Bank | $52,504 | 0.03% | 26,122 | Shares | 2026-08-14 | |
| Large MERCER GLOBAL ADVISORS INC /ADV Registered adviser | $51,263 | 0.03% | 25,504 | Shares | 2026-08-19 | |
| Mid GROUP ONE TRADING LLC Broker-dealer | $50,668 | 0.03% | 25,208 | Shares | 2026-08-14 | |
| Large INTECH INVESTMENT MANAGEMENT LLC Registered adviser | $49,305 | 0.03% | 24,530 | Shares | 2026-08-10 | |
| Mega SUSQUEHANNA INTERNATIONAL GROUP, LLP | $48,487 | 0.03% | 24,123 | Shares | 2026-08-14 | |
| Large Police & Firemen's Retirement System of New Jersey | $47,086 | 0.03% | 23,426 | Shares | 2026-07-23 | |
| Mega VOYA INVESTMENT MANAGEMENT LLC Registered adviser | $44,014 | 0.02% | 21,898 | Shares | 2026-08-12 | |
| Mega BNP PARIBAS ARBITRAGE, SA Non-US | $42,612 | 0.02% | 21,200 | Shares | 2026-08-13 | |
| Mega MANUFACTURERS LIFE INSURANCE COMPANY, THE Non-US | $38,987 | 0.02% | 19,397 | Shares | 2026-09-09 | |
| Mega Qube Research & Technologies Ltd Exempt adviser | $33,303 | 0.02% | 16,569 | Shares | 2026-08-14 | |
| Large CAPTRUST FINANCIAL ADVISORS Registered adviser | $32,234 | 0.02% | 16,037 | Shares | 2026-08-13 | |
| Large PRUDENTIAL FINANCIAL INC Insurer | $32,190 | 0.02% | 16,015 | Shares | 2026-08-12 | |
| Mega Creative Planning Registered adviser | $30,180 | 0.02% | 15,015 | Shares | 2026-08-13 | |
| Mid Tower Research Capital LLC (TRC) | $29,044 | 0.02% | 14,450 | Shares | 2026-08-11 |
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