# EDGAR Filing Document

**Accession Number:** 0001681087
**File Stem:** 0001127602-23-002332
**Filing Date:** 2023-1
**Character Count:** 7239
**Document Hash:** 5e32d5e939aaf23609387aca926a795c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001127602-23-002332.hdr.sgml**: 20230126

**ACCESSION NUMBER**: 0001127602-23-002332

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20221228

**FILED AS OF DATE**: 20230126

**DATE AS OF CHANGE**: 20230126

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** MACKAY GEOFFREY
- **CENTRAL INDEX KEY:** 0001741849

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38537
- **FILM NUMBER:** 23558789

**MAIL ADDRESS:**
- **STREET 1:** C/O AVROBIO, INC.
- **STREET 2:** ONE KENDALL SQ, BLDG. 300, STE. 201
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** AVROBIO, Inc.
- **CENTRAL INDEX KEY:** 0001681087
- **STANDARD INDUSTRIAL CLASSIFICATION:** BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
- **IRS NUMBER:** 810710585
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 100 TECHNOLOGY SQUARE
- **STREET 2:** 6TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139
- **BUSINESS PHONE:** 617.914.8420

**MAIL ADDRESS:**
- **STREET 1:** 100 TECHNOLOGY SQUARE
- **STREET 2:** 6TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02139

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** AvroBio, Inc.
- **DATE OF NAME CHANGE:** 20160729

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>MACKAY GEOFFREY<br><sub>(Last) (First) (Middle)</sub><br>C/O AVROBIO, INC.<br>100 TECHNOLOGY SQUARE, 6TH FLOOR<br><sub>(Street)</sub><br>CAMBRIDGE, MA 02139<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2022-12-28 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_President & CEO_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>AVROBIO, Inc. [ AVRO ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2022-12-28 |  | G | V | 245123<sup>(1)</sup> | D | $0 | 142013 | D |  |
| Common Stock | 2022-12-28 |  | G | V | 245123<sup>(1)</sup> | A | $0 | 445123 | I | By The Geoff R. MacKay Irrevocable Trust |
| Common Stock | 2023-01-24 |  | M |  | 45999 | A | $0.91 | 188012 | D |  |
| Common Stock |  |  |  |  |  |  |  | 72604 | I | By daughter of reporting person |
| Common Stock |  |  |  |  |  |  |  | 72604 | I | By son of reporting person<sup>(2)</sup> |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Stock Option (Right to Buy) | $0.91 | 2023-01-24 |  | M |  |  | 45999 | <sup>(3)</sup> | 2027-06-12 | Common Stock | 45999 | $0 | 0 | D |  |

---

### Footnotes:

(1) This transaction was a bona fide gift of common stock to The Geoff R. MacKay Irrevocable Trust. The reporting person disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

(2) The shares were previously held in a custodial account for the Reporting Person's son, established pursuant to the Uniform Transfers to Minors Act ("UTMA"), for which the Reporting Person served as custodian. The shares have since been distributed to the Reporting Person's son, as required by the terms of the account upon the son attaining the age of 21.  54,453 shares were subsequently transferred to the Mac C. MacKay Irrevocable Trust on December 30, 2022.

(3) 25% of the shares vested on June 13, 2018, and the remaining 75% vested in equal monthly installments thereafter over a three-year period.

**Signature:** /s/ Steven Avruch, Attorney-in-Fact for Geoffrey MacKay  
**Date:** 2023-01-26

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**