# EDGAR Filing Document

**Accession Number:** 0001653087
**File Stem:** 0001193125-23-032861
**Filing Date:** 2023-2
**Character Count:** 8287
**Document Hash:** 84033998da5b7c9d141e9f22b973513c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-23-032861.hdr.sgml**: 20230210

**ACCESSION NUMBER**: 0001193125-23-032861

**CONFORMED SUBMISSION TYPE**: SC 13G/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20230210

**DATE AS OF CHANGE**: 20230210

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Alector, Inc.
- **CENTRAL INDEX KEY:** 0001653087
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **IRS NUMBER:** 822933343
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SC 13G/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-90858
- **FILM NUMBER:** 23613412

**BUSINESS ADDRESS:**
- **STREET 1:** 131 OYSTER POINT BLVD., SUITE 600
- **CITY:** SOUTH SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94080
- **BUSINESS PHONE:** 415-231-5660

**MAIL ADDRESS:**
- **STREET 1:** 131 OYSTER POINT BLVD., SUITE 600
- **CITY:** SOUTH SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94080

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Alector LLC
- **DATE OF NAME CHANGE:** 20150915
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Rosenthal Arnon
- **CENTRAL INDEX KEY:** 0001757770

**FILING VALUES:**
- **FORM TYPE:** SC 13G/A

**MAIL ADDRESS:**
- **STREET 1:** C/O ALECTOR, INC.
- **STREET 2:** 151 OYSTER POINT BLVD., #300
- **CITY:** SOUTH SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94080

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**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

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**SCHEDULE 13G** 

**UNDER THE SECURITIES EXCHANGE ACT OF 1934** 

**(Amendment No. 1)\*** 

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## ALECTOR, INC.
**(Name of Issuer)** 

**Common Stock, $0.0001 par value per share** 

**(Title of Class of Securities)** 

**014442 107** 

**(CUSIP Number)** 

**December 31, 2022** 

**(Date of Event Which Requires Filing of this Statement)** 

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Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☐ Rule 13d-1(c)

☒ Rule 13d-1(d)

\* The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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CUSIP No. 014442 107

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| | |
|:---|:---|
| &nbsp;&nbsp;&nbsp; 1 | &nbsp;&nbsp;&nbsp;&nbsp;NAME OF REPORTING PERSON:<br> &nbsp;&nbsp;&nbsp;&nbsp;I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):<br>&nbsp;&nbsp;&nbsp;&nbsp;Arnon Rosenthal |
| &nbsp;&nbsp;&nbsp; 2 | &nbsp;&nbsp;&nbsp;&nbsp;CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):<br> &nbsp;&nbsp;&nbsp;&nbsp;(a) ☐ (b) ☐ |
| &nbsp;&nbsp;&nbsp; 3 | &nbsp;&nbsp;&nbsp;&nbsp;SEC USE ONLY: |
| &nbsp;&nbsp;&nbsp; 4 | &nbsp;&nbsp;&nbsp;&nbsp;CITIZENSHIP OR PLACE OF ORGANIZATION:<br>&nbsp;&nbsp;&nbsp;&nbsp;United States |

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| | |
|:---|:---|
| &nbsp;&nbsp;&nbsp; NUMBER OF<br> SHARES<br> BENEFICIALLY <br> OWNED BY<br> EACH<br> REPORTING<br> PERSON<br> WITH | 5 |
| &nbsp;&nbsp;&nbsp; NUMBER OF<br> SHARES<br> BENEFICIALLY <br> OWNED BY<br> EACH<br> REPORTING<br> PERSON<br> WITH | 6 &nbsp;&nbsp;&nbsp;&nbsp;SHARED VOTING POWER<br>&nbsp;&nbsp;&nbsp;&nbsp;3,930,375<sup>(2)</sup> |
| &nbsp;&nbsp;&nbsp; NUMBER OF<br> SHARES<br> BENEFICIALLY <br> OWNED BY<br> EACH<br> REPORTING<br> PERSON<br> WITH | 7 &nbsp;&nbsp;&nbsp;&nbsp;SOLE DISPOSITIVE POWER<br>&nbsp;&nbsp;&nbsp;&nbsp;2,953,987<sup>(1)</sup> |
| &nbsp;&nbsp;&nbsp; NUMBER OF<br> SHARES<br> BENEFICIALLY <br> OWNED BY<br> EACH<br> REPORTING<br> PERSON<br> WITH | 8 &nbsp;&nbsp;&nbsp;&nbsp;SHARED DISPOSITIVE POWER<br>&nbsp;&nbsp;&nbsp;&nbsp;3,930,375<sup>(2)</sup> |

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| | |
|:---|:---|
| &nbsp;&nbsp;&nbsp; 9 | &nbsp;&nbsp;&nbsp;&nbsp;AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:<br>&nbsp;&nbsp;&nbsp;&nbsp;6,884,362<sup>(1)(2)</sup>  |
| &nbsp;&nbsp;&nbsp;10 | &nbsp;&nbsp;&nbsp;&nbsp;CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):<br>&nbsp;&nbsp;&nbsp;&nbsp;☐ |
| &nbsp;&nbsp;&nbsp;11 | <br> &nbsp;&nbsp;&nbsp;&nbsp;8.3%<sup>(3)</sup> |
| &nbsp;&nbsp;&nbsp;12 | &nbsp;&nbsp;&nbsp;&nbsp;TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):<br>&nbsp;&nbsp;&nbsp;&nbsp;IN |

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<sup>(1)</sup> Consists of (i) 1,305,226 shares of common stock held of record by Arnon Rosenthal (the "Reporting Person"); (ii) 1,633,831 shares of common stock that are issuable upon exercise of outstanding options within 60 days of December 31, 2022 to the Reporting Person and (iii) 14,930 shares of common stock that are issuable upon vesting of restricted stock units within 60 days of December 31, 2022 to the Reporting Person. 

<sup>(2)</sup> Consists of (i) 1,972,875 shares of common stock held of record by The Rosenthal Family Revocable Trust Dated November 4, 1994, as restated on June 9, 1999, for which the Reporting Person serves as trustee; (ii) 652,500 shares of common stock held of record by The Adi Rosenthal 2007 Trust dated March 27, 2007, for which the Reporting Person serves as trustee; (iii) 652,500 shares of common stock held of record by The Noam Rosenthal 2007 Trust dated March 27, 2007, for which the Reporting Person serves as trustee and (iv) 652,500 shares of common stock held of record by The Shani Rosenthal 2007 Trust dated March 27, 2007, for which the Reporting Person serves as trustee. 

<sup>(3)</sup> Based on 82,701,539 shares of the Issuer's common stock outstanding as of November 3, 2022, as reported in the Issuer's Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2022, filed with the Securities and Exchange Commission on November 8, 2022.

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**Item 1** 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(a) Name of Issuer:** 

Alector, Inc.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(b) Address of Issuer's Principal Executive Offices:** 

131 Oyster Point Blvd., Suite 600

South San Francisco, California 94080

**Item 2** 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(a) Names of Persons Filing:** 

Arnon Rosenthal (the "Reporting Person")

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(b) Address or principal business office or, if none, residence:** 

The principal business office address of the Reporting Person is:

c/o Alector, Inc.

131 Oyster Point Blvd., Suite 600

South San Francisco, California 94080

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(c) Citizenship:** 

Reference is made to the response to item 4 on page 2 of this Schedule 13G (this "Schedule"), which responses are incorporated herein by reference.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(d) Title and Class of Securities:** 

Common Stock, par value $0.0001 per share.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(e) CUSIP No.:** 

014442 107

**Item 3. If this statement is filed pursuant to Rules 13d-1(b) or 13d-2(b) or (c), check whether the person filing is a:** 

Not applicable.

**Item 4. Ownership** 

Reference is hereby made to the responses to items 5-9 and 11 of page 2, which responses are incorporated herein by reference.

**Item 5. Ownership of Five Percent or Less of a Class** 

Not applicable.

**Item 6. Ownership of More than 5 Percent on Behalf of Another Person** 

Not applicable.

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**Item 7. Identification and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.** 

Not applicable.

**Item 8. Identification and Classification of Members of the Group** 

Not applicable.

**Item 9. Notice of Dissolution of Group** 

Not applicable.

**Item 10. Certifications** 

Not applicable.

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**SIGNATURES** 

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: February 10, 2023

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| |
|:---|
| /s/ Arnon Rosenthal |
| Arnon Rosenthal |

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