Arnon Rosenthal - 02 Mar 2026 Form 4 Insider Report for Alector, Inc. (ALEC)

Role
Chief Executive Officer, Director
Signature
/s/ Grace Wong-Sarad, by power of attorney
Issuer symbol
ALEC
Transactions as of
02 Mar 2026
Net transactions value
-$173,822
Form type
4
Filing time
03 Mar 2026, 16:05:20 UTC
Previous filing
03 Dec 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Rosenthal Arnon Chief Executive Officer, Director C/O ALECTOR, INC., 131 OYSTER POINT BLVD., SUITE 600, SOUTH SAN FRANCISCO /s/ Grace Wong-Sarad, by power of attorney 03 Mar 2026 0001757770

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction ALEC Common Stock Sale $173,822 -81,864 -3.4% $2.12 2,338,176 02 Mar 2026 Direct F1, F2
holding ALEC Common Stock 1,972,875 02 Mar 2026 See footnote F3
holding ALEC Common Stock 652,500 02 Mar 2026 See footnote F4
holding ALEC Common Stock 652,500 02 Mar 2026 See footnote F5
holding ALEC Common Stock 652,500 02 Mar 2026 See footnote F6
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.
F2 The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $2.04 to $2.37. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff, the issuer, or any security holder of the issuer upon request.
F3 The reported securities are held directly by The Rosenthal Family Revocable Trust Dated November 4, 1994, as restated on June 9, 1999, for which the Reporting Person serves as trustee.
F4 The reported securities are held directly by the Adi Rosenthal 2007 Trust dated March 27, 2007, for which the Reporting Person serves as trustee.
F5 The reported securities are held directly by the Noam Rosenthal 2007 Trust dated March 27, 2007, for which the Reporting Person serves as trustee.
F6 The reported securities are held directly by the Shani Rosenthal 2007 Trust dated March 27, 2007, for which the Reporting Person serves as trustee.