Alector, Inc. - Common Stock, $0.0001 par value per share (ALEC)

CUSIP: 014442107

Q1 2026 13F Holders as of 31 Mar 2026

Security identity
Security type / class
Equity / Common Stock, $0.0001 par value per share
Shares outstanding
110,074,447
Holder snapshot
Total 13F shares
88,395,563
Share change
+4,088,139
Total reported value
$189,988,470
Put/Call ratio
0%
Reported price per share
$2.15
Number of holders
137
Value change
+$10,033,251
Number of buys
69
Number of sells
54

Security key

014442107

Report period

Q1 2026

Institutions

137

Top holders

10

ALEC full security history Ownership snapshot Full 13F holder table Previous quarter: Q4 2025 Alector, Inc. SEC filings Alector, Inc. company facts

Broader feeds

Latest 13F filings Latest 13D/G filings Investors directory

Ownership snapshot

Top reported holders of ALEC - Alector, Inc. - Common Stock, $0.0001 par value per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Lead holder
TCG Crossover GP II, LLC
13D/G signal
TCG Crossover GP II, LLC
Evidence rows
15
Latest as of
31 Mar 2026
13D/G 3/4/5 13F Lead comparable stake: 9.2% 13D/G row: TCG Crossover GP II, LLC Showing 1-6 of 15 holder rows.
Holder Evidence Ownership % Position 12M Net Δ As of
TCG Crossover GP II, LLC
13D/G
Chen Yu
13D/G
9.2%
$29,600,000
10,000,000 shares
 $0 22 Oct 2025
Arnon Rosenthal
13D/G 3/4/5
Chief Executive Officer, Director
13D/G 3/4/5
7.4%
$12,813,723
8,213,925 shares
 $0 31 Dec 2025
BlackRock, Inc.
13D/G 13F
Company
13D/G 13F
5.2%
$12,436,060
5,784,214 shares
 +$1,299,479 31 Mar 2026
Polaris Venture Partners VI, L.P.
13D/G
Terrance G. McGuire
13D/G
4.7%
$12,157,723
5,173,499 shares
 -$4,516,117 31 Mar 2026
FMR LLC
13D/G 13F
Company
13D/G 13F
3.6%
$10,655,467
3,599,820 shares
 $0 31 Oct 2025
Marc Grasso
3/4/5
Chief Financial Officer
3/4/5
0.27%
$396,262
296,072 shares
 -$22,068 02 Jun 2025
How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

13F holder rows

Institutional holders as of Q1 2026

Investor-level positions for this CUSIP, loaded as an interactive table.

Institutions
137
Shares
88,395,563
Rows available
137
Investor Option Weight % Change % Reported value * Price Shares Share Change Activity Report Period

* Reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that failed the local validity check.

Compare Q1 2026 vs Q4 2025 Across Filers

Q4 2025 holders
129
Q1 2026 holders
137
Holder diff
8
Investor Q4 2025 Shares Q1 2026 Shares Share Diff Share Chg % Q4 2025 value Q1 2026 value Value change Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend
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