ALECTOR INC ALEC
COM · Common Stock · CUSIP 014442107 · ISIN US0144421072
Company in San Francisco, United States
- SectorHealth care
- IndustryBiological Products, (No Diagnostic Substances)
- HeadquartersSouth San Francisco, CA
- Founded2013
- Websitealector.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($431.7k this quarter). Holder counts are more reliable. Shares outstanding: 97.3m as of 2024-08-02, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $4.54. Options: 6 managers hold calls ($299.9k notional), 4 hold puts ($67.6k).
Trends to Q2 2024
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 168 |
| Q4 2022 | 155 |
| Q1 2023 | 150 |
| Q2 2023 | 146 |
| Q3 2023 | 150 |
| Q4 2023 | 149 |
| Q1 2024 | 158 |
| Q2 2024 | 161 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q4 2022 | 68 | 77 |
| Q1 2023 | 67 | 58 |
| Q2 2023 | 69 | 58 |
| Q3 2023 | 79 | 56 |
| Q4 2023 | 63 | 65 |
| Q1 2024 | 88 | 52 |
| Q2 2024 | 80 | 68 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2023 | $441.6k | $339.6k | 0.77 |
| Q4 2023 | $540.9k | $674.6k | 1.25 |
| Q1 2024 | $424.8k | $5.2k | 0.01 |
| Q2 2024 | $299.9k | $67.6k | 0.23 |
Biggest buyers
| Soleus Capital Management, L.P. | New | +2.2m |
| BAKER BROS. ADVISORS LP | New | +927.3k |
| Deep Track Capital, LP | Added | +862.6k |
| BlackRock Inc. | Added | +617.9k |
| VANGUARD GROUP INC | Added | +408.4k |
| GEODE CAPITAL MANAGEMENT, LLC | Added | +179.8k |
| ACADIAN ASSET MANAGEMENT LLC | Added | +146.0k |
| ADAR1 Capital Management, LLC | Added | +142.8k |
| PANAGORA ASSET MANAGEMENT INC | Added | +135.6k |
| ExodusPoint Capital Management, LP | New | +130.1k |
Biggest sellers
| MORGAN STANLEY | Reduced | -6.9m |
| EcoR1 Capital, LLC | Sold out | -4.1m |
| STATE STREET CORP | Reduced | -1.1m |
| Verition Fund Management LLC | Reduced | -714.9k |
| DEUTSCHE BANK AG\ | Reduced | -414.6k |
| CITIGROUP INC | Reduced | -208.4k |
| Woodline Partners LP | Sold out | -190.0k |
| Rafferty Asset Management, LLC | Reduced | -175.0k |
| DIMENSIONAL FUND ADVISORS LP | Reduced | -169.9k |
| BIT Capital GmbH | Sold out | -141.4k |
Biggest calls
| BOOTHBAY FUND MANAGEMENT, LLC | Unchanged | $201.6k44.4k shares |
| CITADEL ADVISORS LLC | Reduced | $38.1k8.4k shares |
| Worth Venture Partners, LLC | New | $36.1k23.3k shares |
| BANK OF AMERICA CORP /DE/ | New | $19.1k4.2k shares |
| SIMPLEX TRADING, LLC | Unchanged | $5.0k1.3k shares |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | Unchanged | $00 shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | New | $45.9k10.1k shares |
| CITADEL ADVISORS LLC | Added | $21.8k4.8k shares |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | Unchanged | $00 shares |
| SIMPLEX TRADING, LLC | Reduced | $0200 shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| TCG Crossover GP II, LLC 13G · passive investor new · filed 2025-11-14 | 9.2% |
| Deep Track Capital, LP 13G · passive investor new · filed 2026-10-23 | 8.6% |
| BIOTECHNOLOGY VALUE FUND L P 13G · passive investor new · filed 2026-09-18 | 8.4% |
| Rosenthal Arnon 13G · exempt (held before listing) filed 2026-02-06 | 7.4% |
| BlackRock, Inc. 13G · institution +0.5 pts · filed 2026-04-27 | 5.2% |
| RA CAPITAL MANAGEMENT, L.P. 13G · passive investor +5.1 pts · filed 2026-10-26 | 5.1% |
Fell to 5% or below in the last year: Polaris Venture Partners VI, L.P. (4.7%, 2026-05-14), VANGUARD GROUP INC (0.0%, 2026-03-26), RTW INVESTMENTS, LP (0.0%, 2026-02-17)
Insider purchases and sales in Q2 2024
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q3 2022 | 0 | — | 2 | $25.0k | — |
| Q4 2022 | 0 | — | 1 | $18.7k | — |
| Q1 2023 | 0 | — | 4 | $265.0k | — |
| Q2 2023 | 0 | — | 4 | $89.8k | — |
| Q3 2023 | 0 | — | 5 | $3.1m | — |
| Q4 2023 | 0 | — | 4 | $255.5k | — |
| Q1 2024 | 0 | — | 4 | $281.8k | — |
| Q2 2024 | 0 | — | 4 | $255.8k | — |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2024-06-03 | Rosenthal Arnon Chief Executive Officer, director | Sold | $120.6k25.1k shares |
| 2024-06-03 | Kenkare-Mitra Sara President and Head of R&D | Sold | $63.4k13.2k shares |
| 2024-06-03 | Romano Gary Chief Medical Officer | Sold | $38.6k8.0k shares |
| 2024-06-03 | GRASSO MARC Chief Financial Officer | Sold | $33.2k6.9k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q2 2024
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.00% of their portfolio | 14.5m $65.6m | Added +94.8k |
| BlackRock Inc. 0.00% of their portfolio | 9.1m $41.3m | Added +617.9k |
| VANGUARD GROUP INC 0.00% of their portfolio | 5.3m $24.2m | Added +408.4k |
| Deep Track Capital, LP 0.63% of their portfolio | 4.6m $21.0m | Added +862.6k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 3.3m $15.0m | Reduced -118.5k |
| MORGAN STANLEY 0.00% of their portfolio | 3.0m $13.6m | Reduced -6.9m |
| STATE STREET CORP 0.00% of their portfolio | 2.8m $12.7m | Reduced -1.1m |
| BRAIDWELL LP 0.34% of their portfolio | 2.4m $10.8m | Unchanged |
| Soleus Capital Management, L.P. 0.90% of their portfolio | 2.2m $10.2m | New |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 2.2m $10.1m | Reduced -414.6k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 1.8m $8.0m | Added +179.8k |
| Euclidean Capital LLC 0.75% of their portfolio | 1.3m $5.9m | Unchanged |
| DEERFIELD MANAGEMENT COMPANY, L.P. 0.09% of their portfolio | 1.1m $5.2m | Added +75.5k |
| FRANKLIN RESOURCES INC 0.00% of their portfolio | 963.4k $4.4m | Added +3.8k |
| BAKER BROS. ADVISORS LP 0.05% of their portfolio | 927.3k $4.2m | New |
| DAFNA Capital Management LLC 0.99% of their portfolio | 912.9k $4.1m | Unchanged |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 869.6k $3.9m | Reduced -20.9k |
| JACOBS LEVY EQUITY MANAGEMENT, INC 0.02% of their portfolio | 858.6k $3.9m | Reduced -64.2k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 767.0k $3.5m | Added +41.3k |
| DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio | 676.1k $3.1m | Reduced -169.9k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 666.5k $3.0m | Reduced -8.3k |
| RENAISSANCE TECHNOLOGIES LLC 0.01% of their portfolio | 655.0k $3.0m | Reduced -20.4k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 648.7k $2.9m | Reduced -21.5k |
| Point72 Asset Management, L.P. 0.01% of their portfolio | 614.4k $2.8m | Reduced -80.9k |
| SPHERA FUNDS MANAGEMENT LTD. 0.45% of their portfolio | 610.0k $2.8m | Added +50.0k |
| ACADIAN ASSET MANAGEMENT LLC 0.01% of their portfolio | 590.7k $2.7m | Added +146.0k |
| Eversept Partners, LP 0.19% of their portfolio | 541.7k $2.5m | Added +5.6k |
| Verition Fund Management LLC 0.02% of their portfolio | 538.2k $2.4m | Reduced -714.9k |
| TWO SIGMA ADVISERS, LP 0.00% of their portfolio | 479.7k $2.2m | Reduced -59.8k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 388.4k $1.8m | Added +69.1k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 359.4k $1.6m | Added +5.7k |
| PANAGORA ASSET MANAGEMENT INC 0.01% of their portfolio | 355.3k $1.6m | Added +135.6k |
| D. E. Shaw & Co., Inc. 0.00% of their portfolio | 352.2k $1.6m | Added +22.6k |
| New Leaf Venture Partners, L.L.C. 1.87% of their portfolio | 339.6k $1.5m | Unchanged |
| TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio | 302.1k $1.4m | Reduced -62.5k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 279.9k $1.3m | Added +49.6k |
| Walleye Capital LLC 0.01% of their portfolio | 278.3k $1.3m | Added +25.5k |
| Nuveen Asset Management, LLC 0.00% of their portfolio | 269.1k $1.2m | Reduced -70.8k |
| BAILLIE GIFFORD & CO 0.00% of their portfolio | 260.4k $1.2m | Reduced -62.4k |
| Alyeska Investment Group, L.P. 0.01% of their portfolio | 256.2k $1.2m | Unchanged |
| JUPITER ASSET MANAGEMENT LTD 0.01% of their portfolio | 232.2k $1.1m | Unchanged |
| STIFEL FINANCIAL CORP 0.00% of their portfolio | 214.0k $971.6k | Added +67.3k |
| ADAR1 Capital Management, LLC 0.18% of their portfolio | 195.3k $886.7k | Added +142.8k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 184.5k $837.7k | Reduced -5.7k |
| Alphabet Inc. 0.04% of their portfolio | 175.9k $798.4k | Unchanged |
| MEDICI CAPITAL LLC 1.67% of their portfolio | 167.2k $759.0k | Reduced -18.7k |
| NORDEA INVESTMENT MANAGEMENT AB 0.00% of their portfolio | 160.0k $707.2k | Reduced -28.8k |
| MILLENNIUM MANAGEMENT LLC 0.00% of their portfolio | 156.8k $711.8k | Added +54.6k |
| VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio | 156.2k $709.3k | Added +27.1k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 154.0k $699.1k | Added +79.9k |
| Trexquant Investment LP 0.01% of their portfolio | 146.6k $665.4k | Added +104.1k |
| Swiss National Bank 0.00% of their portfolio | 131.9k $598.8k | Unchanged |
| ExodusPoint Capital Management, LP 0.01% of their portfolio | 130.1k $590.0k | New |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC 0.01% of their portfolio | 129.7k $588.7k | Added +3.5k |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio | 124.8k $566.7k | Added +6.8k |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 124.8k $566.4k | Added +88.3k |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.00% of their portfolio | 112.9k $512.7k | Added +3.8k |
| TD Asset Management Inc 0.00% of their portfolio | 111.7k $507.3k | Unchanged |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 109.9k $499.0k | Added +18.4k |
| UBS Group AG 0.00% of their portfolio | 105.7k $479.8k | Reduced -123.8k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 103.1k $468.1k | Added +1.0k |
| STRS OHIO 0.00% of their portfolio | 102.6k $465.8k | Added +11.4k |
| Rafferty Asset Management, LLC 0.00% of their portfolio | 100.6k $456.9k | Reduced -175.0k |
| EntryPoint Capital, LLC 0.21% of their portfolio | 100.4k $456.0k | New |
| DekaBank Deutsche Girozentrale 0.00% of their portfolio | 100.0k $437.0k | Unchanged |
| Cubist Systematic Strategies, LLC 0.01% of their portfolio | 92.2k $418.7k | Added +38.9k |
| Y-Intercept (Hong Kong) Ltd 0.02% of their portfolio | 89.9k $408.1k | New |
| Russell Investments Group, Ltd. 0.00% of their portfolio | 83.8k $380.5k | Added +5.5k |
| Corton Capital Inc. 0.19% of their portfolio | 79.9k $362.6k | New |
| BARCLAYS PLC 0.00% of their portfolio | 76.1k $345.4k | Reduced -26.2k |
| ALPS ADVISORS INC 0.00% of their portfolio | 75.2k $341.3k | Added +7.6k |
| FEDERATED HERMES, INC. 0.00% of their portfolio | 68.5k $311.2k | Added +2.7k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.00% of their portfolio | 68.2k $309.5k | First filing |
| BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio | 67.6k $306.9k | Added +23.7k |
| Man Group plc 0.00% of their portfolio | 67.5k $306.6k | Added +2.2k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 66.7k $302.8k | Reduced -364 |
| Cannell & Spears LLC 0.01% of their portfolio | 65.7k $298.1k | Reduced -514 |
| SG Americas Securities, LLC 0.00% of their portfolio | 64.2k $291.0k | New |
| LOS ANGELES CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 63.2k $286.9k | Added +4.4k |
| Legal & General Group Plc 0.00% of their portfolio | 61.0k $277.0k | Added +668 |
| MARSHALL WACE, LLP 0.00% of their portfolio | 52.6k $238.8k | Reduced -124.7k |
| Utah Retirement Systems 0.00% of their portfolio | 51.4k $233.5k | Added +20.6k |
| MetLife Investment Management, LLC 0.00% of their portfolio | 50.4k $228.7k | Added +16.0k |
| AMERICAN CENTURY COMPANIES INC 0.00% of their portfolio | 50.1k $227.4k | Reduced -21.3k |
| HSBC HOLDINGS PLC 0.00% of their portfolio | 47.1k $207.9k | Added +21.6k |
| ALGERT GLOBAL LLC 0.01% of their portfolio | 43.5k $197.5k | New |
| Corebridge Financial, Inc. 0.00% of their portfolio | 43.4k $197.1k | First filing |
| PDT Partners, LLC 0.02% of their portfolio | 42.4k $192.7k | Reduced -15.1k |
| STATE OF WISCONSIN INVESTMENT BOARD 0.00% of their portfolio | 39.5k $179.3k | Reduced -15.5k |
| Campbell & CO Investment Adviser LLC 0.02% of their portfolio | 39.1k $177.4k | New |
| Invesco Ltd. 0.00% of their portfolio | 36.5k $165.7k | Added +4.9k |
| TRUIST FINANCIAL CORP 0.00% of their portfolio | 34.0k $154.5k | Reduced -5.8k |
| Vident Advisory, LLC 0.00% of their portfolio | 34.0k $154.3k | Added +12.0k |
| GSA CAPITAL PARTNERS LLP 0.01% of their portfolio | 33.5k $152.0k | Reduced -30.1k |
| CITIGROUP INC 0.00% of their portfolio | 32.5k $147.7k | Reduced -208.4k |
| Amundi 0.00% of their portfolio | 31.8k $140.2k | Reduced -17.1k |
| XTX Topco Ltd 0.01% of their portfolio | 31.1k $141.1k | Added +12.0k |
| Jasper Ridge Partners, L.P. 0.00% of their portfolio | 30.6k $139.1k | Added +15.9k |
| VOYA INVESTMENT MANAGEMENT LLC 0.00% of their portfolio | 27.8k $126.4k | Added +5.6k |
| Engineers Gate Manager LP 0.00% of their portfolio | 26.6k $120.7k | Added +1.9k |