Bybee Clinton Form 4 Sienna Biopharmaceuticals / CLINTON BYBEE ownership change

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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

1. Name and Address of Reporting Person^*

ARCH Venture Partners VIII, LLC

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Sienna Biopharmaceuticals, Inc. [ SNNA ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
08/01/2017

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

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

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

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/01/2017		C		2,538,641	A	(1)	2,538,641	I	See Footnote(2)
Common Stock	08/01/2017		C		211,934	A	(1)	2,750,575	I	See Footnote(2)
Common Stock	08/01/2017		C		563,072	A	(1)	563,072	I	See Footnote(3)
Common Stock	08/01/2017		C		319,421	A	(1)	882,493	I	See Footnote(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A-3 Preferred Stock	(1)	08/01/2017		C			2,538,641	(1)	(4)	Common Stock	2,538,641	(1)	0	I	See Footnote(2)
Series A-3 Preferred Stock	(1)	08/01/2017		C			563,072	(1)	(4)	Common Stock	563,072	(1)	0	I	See Footnote(3)
Series B Preferred Stock	(1)	08/01/2017		C			211,934	(1)	(4)	Common Stock	211,934	(1)	0	I	See Footnote(2)
Series B Preferred Stock	(1)	08/01/2017		C			319,421	(1)	(4)	Common Stock	319,421	(1)	0	I	See Footnote(3)

1. Name and Address of Reporting Person^*

ARCH Venture Partners VIII, LLC

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Partners VIII, L.P.

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS VIII, LLC

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Fund VIII, L.P.

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS VIII, LLC

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Fund VIII Overage, L.P.

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS VIII, LLC

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

BYBEE CLINTON

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS VIII, LLC

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

CRANDELL KEITH

(Last) (First) (Middle)

C/O ARCH VENTURE PARTNERS VIII, LLC

8755 W. HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

Explanation of Responses:

1. The shares of the Issuer's Preferred Stock automatically converted into shares of the Issuer's Common Stock, for no additional consideration, on a 1:1 basis immediately prior to the consummation of the Issuer's initial public offering.

2. The shares are directly held by ARCH Venture Fund VIII, L.P. ("ARCH VIII"). ARCH Venture Partners VIII, L.P. (the "GPLP"), as the sole general partner of ARCH VIII, may be deemed to beneficially own certain of the shares held by ARCH VIII. ARCH Venture Partners VIII, LLC ("GPLLC"), as the sole general partner of GPLP, may be deemed to beneficially own the shares held by ARCH VIII. Keith Crandell and Clinton Bybee are managing directors of GPLLC, and as such may be deemed to beneficially own the shares held by ARCH VIII. Each Reporting Person disclaims beneficial ownership of such shares except to the extent of any pecuniary interest therein.

3. The shares are directly held by ARCH Venture Fund VIII Overage, L.P. ("ARCH Overage"). GPLLC, as the sole general partner of ARCH Overage, may be deemed to beneficially own the shares held by ARCH Overage. Keith Crandell and Clinton Bybee are managing directors of GPLLC, and as such may be deemed to beneficially own the shares held by ARCH Overage. Each Reporting Person disclaims beneficial ownership of such shares except to the extent of any pecuniary interest therein.

4. The expiration date is not relevant to the conversion of these securities.

	ARCH Venture Fund VIII, L.P. By: ARCH Venture Partners VIII, L.P. By: /s/Mark McDonnell, as Attorney-in-Fact for Keith Crandell, the Mgng Dir of ARCH Venture Partners VIII LLC, the GP of ARCH Venture Partners VIII, L.P., the GP of ARCH Venture Fund VIII	08/01/2017
	ARCH Venture Fund VIII Overage, L.P. By: ARCH Venture Partners VIII, LLC By: /s/ Mark McDonnell, as Attorney-in-Fact for Keith Crandell, the Managing Director of ARCH Venture Partners VIII LLC, the GP of ARCH Venture Fund VIII Overage, L.P.	08/01/2017
	ARCH Venture Partners VIII, L.P. By: ARCH Venture Partners VIII, LLC By: /s/ Mark McDonnell as Attorney-in-Fact for Keith Crandell, the Managing Director of ARCH Venture Partners VIII LLC, the GP of ARCH Venture Partners VIII, L.P.	08/01/2017
	ARCH Venture Partners VIII, LLC By: /s/ Mark McDonnell as Attorney-in-Fact for Keith Crandell, the Managing Director of ARCH Venture Partners VIII, LLC	08/01/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for Keith Crandell	08/01/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for Clinton Bybee	08/01/2017
	** Signature of Reporting Person	Date
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