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

Reporting relationship: Chief Executive Officer, Director
Issuer ticker: ALEC
Reported as of: 02 Jun 2026
Net transaction value: -$172,191
SEC form: 4
Accepted by SEC: 03 Jun 2026, 17:30:17 UTC
Prior SEC filing: 13 Mar 2026
Source filing: View source filing
Reporting owner signature: /s/ Grace Wong-Sarad, by power of attorney

Key filing fact

Arnon Rosenthal filed Form 4 for Alector, Inc. (ALEC) on 03 Jun 2026.

Key facts

This page summarizes Arnon Rosenthal's Form 4 filing for Alector, Inc. (ALEC).
1 reported transaction and 0 derivative rows are listed below.
Accepted by SEC: 03 Jun 2026, 17:30.

Change

Previous filing in this sequence was filed on 13 Mar 2026.
Current net transaction value: -$172,191.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001757770 Primary reporting owner

Rosenthal Arnon

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

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ALEC transaction

Common Stock

Sale

Transaction value: $172,191
Shares: -87,216
Change %: -3.6%
Price: $1.97
Shares after: 2,367,206
Date: 02 Jun 2026
Ownership: Direct
Footnotes: F1, F2

ALEC holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 1,972,875
Date: 02 Jun 2026
Ownership: See footnote
Footnotes: F3

ALEC holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 652,500
Date: 02 Jun 2026
Ownership: See footnote
Footnotes: F4

ALEC holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 652,500
Date: 02 Jun 2026
Ownership: See footnote
Footnotes: F5

ALEC holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 652,500
Date: 02 Jun 2026
Ownership: See footnote
Footnotes: F6

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 6 footnotes

Footnote 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.

Footnote F2

The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $1.92 to $2.08. 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.

Footnote 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.

Footnote 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.

Footnote 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.

Footnote 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.