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<?xml version="1.0" standalone="yes" encoding="windows-1252"?> |
<!-- DFIN ActiveDisclosure(SM) XBRL Instance Document - http://www.dfinsolutions.com/ --> |
<!-- Creation Date : 2021-03-27T23:35:50.2734971+00:00 --> |
<!-- Version : 5.0.1.571 --> |
<!-- Package ID : 77f1e9141cab43e2a10572340983a6c5 --> |
<!-- Copyright (c) 2021 Donnelley Financial Solutions, Inc. All Rights Reserved. --> |
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| | | <xbrli:identifier scheme="http://www.sec.gov/CIK"> 0001653087 </xbrli:identifier> |
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| | | <xbrli:instant> 2021-02-15 </xbrli:instant> |
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| <dei:EntityAddressAddressLine2 id="F_000010" contextRef="C_0001653087_20200101_20201231"> Suite 600 </dei:EntityAddressAddressLine2> |
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| <dei:DocumentsIncorporatedByReferenceTextBlock id="F_000034" contextRef="C_0001653087_20200101_20201231"> <p>Portions of the registrant’s Definitive Proxy Statement relating to the registrant’s Annual Meeting of Shareholders are incorporated by reference into Part III of this Annual Report on Form 10-K where indicated. Such Definitive Proxy Statement will be filed with the Securities and Exchange Commission within 120 days after the end of the registrant’s 2020 fiscal year ended December 31, 2020.</p> </dei:DocumentsIncorporatedByReferenceTextBlock> |
| <dei:AmendmentDescription id="F_000035" contextRef="C_0001653087_20200101_20201231"> This Amendment No. 1 (“Amendment”) on Form 10-K/A amends the annual report on Form 10-K of Alector, Inc. (the “Company”) for the period ended December 31, 2020, as filed with the Securities and Exchange Commission (the “Commission”) on February 25, 2021 (the “Form 10-K”). This Amendment is an exhibit-only filing solely for the purpose of filing revised Exhibits 31.1 and 31.2 to comply with Section 302 of the Sarbanes-Oxley Act of 2002. No revisions are being made to the Company’s financial statements and this Amendment does not reflect events occurring after the filing of the Form 10-K, or modify or update those disclosures that may be affected by subsequent events, and no other changes are being made to any other disclosure contained in the Form 10-K. </dei:AmendmentDescription> |
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