Polaris Venture Partners VI, L.P. - 30 Sep 2025 SCHEDULE 13G/A Report for Alector, Inc. Common Stock, $0.0001 par value per share (ALEC)

Filing Manager
Polaris Venture Partners VI, L.P.
Reporting Manager
Terrance G. McGuire
Security
Alector, Inc. Common Stock, $0.0001 par value per share
Symbol
ALEC
Shares outstanding
109,157,708 shares
Disclosed Ownership
7,095,251 shares
Ownership
6.5%
Form type
SCHEDULE 13G/A
Filing time
13 Nov 2025, 16:41:55 UTC
Date of event
30 Sep 2025
SEC
View on sec.gov

Reporting Managers (11)

Name Ownership Shares Owned sole voting power shared voting power Signature Title CIK
Polaris Venture Partners VI, L.P. 0.5% 498,468 498,468 0 /s/ Lauren Crockett Lauren Crockett/ Authorized Signatory of Polaris Venture Management Co. VI, L.L.C., general partner of Polaris Venture Partners VI, L.P.
Polaris Venture Partners Founders' Fund VI, L.P. 0.3% 378,403 378,403 0 /s/ Lauren Crockett Lauren Crockett/ Authorized Signatory of Polaris Venture Management Co. VI, L.L.C., GP of Polaris Venture Partners Founders' Fund VI, L.P.
Polaris Venture Partners VI (AIV), L.P. 4.4% 4,797,563 4,797,563 0 /s/ Lauren Crockett Lauren Crockett/ Authorized Signatory of Polaris Venture Management Co. VI, L.L.C., general partner of Polaris Venture Partners VI (AIV), L.P.
Polaris Venture Partners VI (AIV-B), L.P. 1.1% 1,179,383 1,179,383 0 /s/ Lauren Crockett Lauren Crockett/ Authorized Signatory of Polaris Venture Management Co. VI, L.L.C., general partner of Polaris Venture Partners VI (AIV-B), L.P.
Polaris Venture Management Co VI, L.L.C. 6.3% 6,853,817 0 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Authorized Signatory*
David Barrett 6.3% 6,880,071 26,254 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Attorney-In-Fact
Brian Chee 6.3% 6,880,084 26,267 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Attorney-In-Fact
Jonathan A. Flint 6.3% 6,892,942 39,125 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Attorney-In-Fact
Terrance G. McGuire 6.5% 7,095,251 241,434 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Attorney-In-Fact
Amir Nashat 6.4% 6,932,617 78,800 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Attorney-In-Fact
Bryce Youngren 6.4% 6,945,149 91,332 6,853,817 /s/ Lauren Crockett Lauren Crockett/ Attorney-In-Fact