Alector Inc. Watch

from 10-Q 5 pages Alector, Inc. Outside Director Compensation Policy as Amended and Restated on April 30, 2024

from 10-Q 3 pages Alector, Inc. 131 Oyster Point Blvd., Suite 600, South San Francisco, Ca 94080 United States of America March 11, 2024

from 10-K 6 pages Alector, Inc. Outside Director Compensation Policy

from 10-K 19 pages Purpose. the Purpose of the Plan Is to Provide Employees of the Company and Its Designated Companies With an Opportunity to Purchase Common Stock Through Accumulated Contributions. the Company Intends for the Plan to Have Two Components: A Component That Is Intended to Qualify as an “Employee Stock Purchase Plan” Under Section 423 of the Code (The “423 Component”) and a Component That Is Not Intended to Qualify as an “Employee Stock Purchase Plan” Under Section 423 of the Code (The “Non-423 Component”). the Provisions of the 423 Component, Accordingly, Will Be Construed So as to Extend and Limit Plan Participation in a Uniform and Nondiscriminatory Basis Consistent With the Requirements of Section 423 of the Code. an Option to Purchase Shares of Common Stock Under the Non-423 Component Will Be Granted Pursuant to Rules, Procedures, or Sub-Plans Adopted by the Administrator Designed to Achieve Tax, Securities Laws, or Other Objectives for Eligible Employees and the Company. Except as Otherwise Provided Herein, the Non-423 Component Will Operate and Be Administered in the Same Manner as the 423 Component. 2. Definitions. (A) “Administrator” Means the Board or Any Committee Designated by the Board to Administer the Plan Pursuant to Section 14. (B) “Affiliate” Means Any Entity, Other Than a Subsidiary, in Which the Company Has an Equity or Other Ownership Interest

from 10-K 47 pages Alector, Inc. 2019 Equity Incentive Plan 1. Purposes of the Plan. the Purposes of This Plan Are: • to Attract and Retain the Best Available Personnel for Positions of Substantial Responsibility, • to Provide Additional Incentive to Employees, Directors and Consultants, and • to Promote the Success of the Company’s Business. the Plan Permits the Grant of Incentive Stock Options, Nonstatutory Stock Options, Restricted Stock, Restricted Stock Units, Stock Appreciation Rights, Performance Units and Performance Shares. 2. Definitions. as Used Herein, the Following Definitions Will Apply: (A) “Administrator” Means the Board or Any of Its Committees as Will Be Administering the Plan, in Accordance With Section 4 of the Plan

from 10-Q 3 pages Alector, Inc. 131 Oyster Point Blvd., Suite 600 South San Francisco, Ca 94080 United States of America May 19, 2023 By: /S/Arnon Rosenthal Name: Arnon Rosenthal Title: Chief Executive Officer Date: May 30, 2023 Acknowledged and Agreed Glaxo Wellcome Uk Limited By: /S/Marcus Dowding Name: Marcus Dowding Title: Authorized Signatory, Corporate Director Date: May 23, 2023 2

from 10-Q 6 pages Amendment No. 1 to Co-Development and Option Agreement

from 10-K 3 pages Amendment Number One to the 2019 Collaboration Agreement

from 10-K 6 pages Alector, Inc. Outside Director Compensation Policy

from 8-K 43 pages Alector, Inc. 2022 Inducement Equity Incentive Plan

from 8-K 8 pages Material contract

from 10-K 6 pages Material contract

from 10-K 5 pages Material contract

from 8-K 6 pages Material contract

from 8-K 13 pages Separation Agreement and Release of Claims

from 8-K 44 pages Alector, Inc. 2022 Inducement Equity Incentive Plan

from 10-Q 7 pages Confidential Consulting Agreement

from 8-K 3 pages September 3, 2021 Re: Confirmation of Agreement to Separate Employment via Email & Regular Mail Robert Paul Re: Confirmation of Mutual Agreement to Separate Employment Dear Robert

from 8-K 4 pages Transition Agreement

from 10-Q 129 pages Collaboration and License Agreement by and Between Alector, Inc. and Glaxo Wellcome Uk Limited