SEC FORM 3

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

GILLIS STEVEN

(Last)

(First)

(Middle)

C/O ARCH VENTURE PARTNERS

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO

60631

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
03/27/2018

3. Issuer Name and Ticker or Trading Symbol
Homology Medicines, Inc. [ FIXX ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	10% Owner
	Officer (give title below)	Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
Series A Preferred Stock	⁽¹⁾	⁽¹⁾	Common Stock	4,683,238	⁽¹⁾	I	See footnotes⁽²⁾⁽⁴⁾⁽⁵⁾
Series B Preferred Stock	⁽¹⁾	⁽¹⁾	Common Stock	1,385,457	⁽¹⁾	I	See footnotes⁽³⁾⁽⁴⁾⁽⁵⁾

Explanation of Responses:

1. The preferred stock is convertible into the Issuer's common stock on a one-for-one basis at the holder's election and has no expiration date. The preferred stock will automatically convert into common stock upon the closing of the Issuer's initial public offering.

2. Includes 669,034 and 4,014,204 shares of Series A Preferred Stock held by ARCH Venture Fund VIII Overage, L.P. ("ARCH Fund Overage") and ARCH Venture Fund VIII, L.P. ("ARCH Fund VIII"), respectively.

3. Includes 527,793 and 857,664 shares of Series B Preferred Stock held by ARCH Fund Overage and ARCH Fund VIII, respectively.

4. The sole general partner of ARCH Fund VIII is ARCH Venture Partners VIII, L.P. ("ARCH Partners VIII"). The sole general partner of ARCH Partners VIII and ARCH Fund Overage is ARCH Venture Partners VIII, LLC ("ARCH VIII LLC"). ARCH Partners VIII may therefore be deemed to beneficially own the securities held by ARCH Fund VIII and ARCH VIII LLC may be deemed to beneficially own the securities held by ARCH Fund VIII and ARCH Fund Overage. ARCH Partners VIII and ARCH VIII LLC disclaim beneficial ownership of such securities, except to the extent of any pecuniary interest therein. The managing directors of ARCH VIII LLC are Keith L. Crandell, Clinton Bybee and Robert Nelsen, and they may be deemed to beneficially own the shares held by ARCH Fund VIII and ARCH Fund Overage. Messrs. Crandell, Bybee and Nelsen disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

5. The Reporting Person is a managing director at ARCH Partners VIII and owns an interest in ARCH Partners VIII but does not have voting or investment control over the shares held by ARCH Fund VIII. The Reporting Person disclaims beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

Remarks:

Exhibit 24 - Power of Attorney.

	/s/ Bradford Smith, Attorney-in-Fact for Steven Gillis	03/27/2018
	** Signature of Reporting Person	Date
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 5 (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.