Alector, Inc.
US ˙ NasdaqGS ˙ US0144421072

SecurityALEC / Alector, Inc.
InstitutionDimensional Fund Advisors Lp
Latest Disclosed Ownership283,817 shares
Latest Disclosed Value $ 609,754
Dimensional Fund Advisors Lp reports 42.53% increase in ownership of ALEC / Alector, Inc.

On May 7, 2026 - Dimensional Fund Advisors Lp filed a 13F-HR form disclosing ownership of 283,817 shares of Alector, Inc. (US:ALEC) valued at $610,207 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 199,126 shares of Alector, Inc.. This represents a change in shares of 42.53% during the quarter. The current value of the position is $503,775 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-07 2026-03-31 13F ALECTOR COM 014442107 283,817 84,691 42.53 610 96.45 0.0000
2026-02-12 2025-12-31 13F ALECTOR COM 014442107 199,126 -96,720 -32.69 310 -64.61 0.0001
2025-11-12 2025-09-30 13F ALECTOR COM 014442107 295,846 -87,485 -22.82 876 63.43 0.0002
2025-08-12 2025-06-30 13F ALECTOR COM 014442107 383,331 -106,003 -21.66 537 -10.96 0.0001
2025-05-13 2025-03-31 13F ALECTOR COM 014442107 489,334 -392,786 -44.53 602 -63.87 0.0001
2025-02-13 2024-12-31 13F ALECTOR COM 014442107 882,120 157,231 21.69 1,667 -50.68 0.0004
2024-11-07 2024-09-30 13F ALECTOR COM 014442107 724,889 48,813 7.22 3,379 10.07 0.0008
2024-08-09 2024-06-30 13F ALECTOR COM 014442107 676,076 -169,888 -20.08 3,069 -39.73 0.0008
2024-05-10 2024-03-31 13F ALECTOR COM 014442107 845,964 81,570 10.67 5,093 -16.51 0.0014
2024-02-07 2023-12-31 13F ALECTOR COM 014442107 764,394 83,169 12.21 6,100 38.14 0.0018
2023-11-09 2023-09-30 13F ALECTOR COM 014442107 681,225 128,401 23.23 4,415 32.94 0.0014
2023-08-09 2023-06-30 13F ALECTOR COM 014442107 552,824 113,282 25.77 3,322 22.10 0.0011
2023-05-12 2023-03-31 13F ALECTOR COM 014442107 439,542 274,513 166.34 2,720 271,900.00 0.0009
2023-02-09 2022-12-31 13F ALECTOR COM 014442107 165,029 165,029 2 0.0004
2022-11-10 2022-09-30 13F ALECTOR COM 014442107 0 -44,337 -100.00 0 -100.00
2022-08-12 2022-06-30 13F ALECTOR COM 014442107 44,337 -341,750 -88.52 451 -91.80 0.0002
2022-05-13 2022-03-31 13F ALECTOR COM 014442107 386,087 226,182 141.45 5,502 66.58 0.0017
2022-02-09 2021-12-31 13F ALECTOR COM 014442107 159,905 83,835 110.21 3,303 90.16 0.0010
2021-11-12 2021-09-30 13F ALECTOR COM 014442107 76,070 0 0.00 1,737 9.66 0.0006
2021-08-12 2021-06-30 13F ALECTOR COM 014442107 76,070 -197,015 -72.14 1,584 -71.17 0.0005
2021-05-14 2021-03-31 13F ALECTOR COM 014442107 273,085 185,636 212.28 5,494 315.27 0.0018
2021-03-08 2020-12-31 13F/A-2 ALECTOR COM 014442107 87,449 -824 -0.93 1,323 42.11 0.0005
2021-02-11 2020-12-31 13F ALECTOR COM 014442107 87,449 -824 1,323 477.7973
2020-11-12 2020-09-30 13F ALECTOR COM 014442107 88,273 18,640 26.77 931 -45.27 0.0004
2020-08-13 2020-06-30 13F ALECTOR COM 014442107 69,633 69,633 1,701 0.0007
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.