| Item 1. | |
| (a) | Name of issuer:
UNITY BIOTECHNOLOGY, INC. |
| (b) | Address of issuer's principal executive offices:
124 Washington Street, Suite 101, Foxborough, MA 02035 |
| Item 2. | |
| (a) | Name of person filing:
ARCH Venture Fund VII, L.P. ("ARCH Venture Fund VII"); ARCH Venture Fund VIII Overage, L.P. ("AVF VIII Overage LP"); ARCH Venture Partners VII, L.P. ("AVP VII LP"); ARCH Venture Partners VII, LLC ("AVP VII LLC"); ARCH Venture Partners VIII, LLC ("AVP VIII LLC") (collectively, the "Reporting Entities" and individually, each a "Reporting Entity"); and Keith Crandell ("Crandell"), Robert Nelsen ("Nelsen") and Clinton Bybee ("Bybee") (collectively, the "Managing Directors" and individually, each a "Managing Director"). The Reporting Entities and the Managing Directors collectively are referred to as the "Reporting Persons". |
| (b) | Address or principal business office or, if none, residence:
8755 W. Higgins Avenue, Suite 1025, Chicago, IL 60631 |
| (c) | Citizenship:
ARCH Venture Fund VII, AVF VIII Overage LP and AVP VIII LP are limited partnerships organized under the laws of the State of Delaware. AVP VII LLC and AVP VIII LLC are limited liability companies organized under the laws of the State of Delaware. Each Managing Director is a US citizen. |
| (d) | Title of class of securities:
Common Stock, par value $0.0001 per share |
| (e) | CUSIP No.:
91381U200 |
| Item 3. | If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a: |
| (a) |  Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
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| (b) | Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
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| (c) | Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
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| (d) | Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
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| (e) | An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
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| (f) | An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
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| (g) | A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
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| (h) | A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
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| (i) | A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
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| (j) | A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
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| (k) | Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
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| | |
| Item 4. | Ownership |
| (a) | Amount beneficially owned:
Not applicable. |
| (b) | Percent of class:
0% |
| (c) | Number of shares as to which the person has:
|
| | (i) Sole power to vote or to direct the vote:
0
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| | (ii) Shared power to vote or to direct the vote:
0
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| | (iii) Sole power to dispose or to direct the disposition of:
0
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| | (iv) Shared power to dispose or to direct the disposition of:
0
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| Item 5. | Ownership of 5 Percent or Less of a Class. |
| | 
Ownership of 5 percent or less of a class
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| Item 6. | Ownership of more than 5 Percent on Behalf of Another Person. |
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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. |
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Not Applicable
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| Item 8. | Identification and Classification of Members of the Group. |
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Not Applicable
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| Item 9. | Notice of Dissolution of Group. |
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Not Applicable
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