Richard D Peterson Form 3 Sienna Biopharmaceuticals / RICHARD D PETERSON ownership change

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^*

PETERSON RICHARD D

(Last) (First) (Middle)

C/O SIENNA BIOPHARMACEUTICALS, INC.

30699 RUSSELL RANCH ROAD, SUITE 140

(Street)

WESTLAKE VILLAGE CA 91362

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
07/26/2017

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

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

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

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)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (Right to Buy)	(1)	06/14/2027	Common Stock	147,636	11.04	D

Explanation of Responses:

1. Twenty-five percent (25%) of the shares subject to the option vest and become exercisable on the first anniversary measured from March 24, 2017, and the remaining shares subject to the option vest and become exercisable in 36 successive, equal monthly installments thereafter, subject to the Reporting Person's continued employment or service relationship with the Issuer on each such vesting date.

	/s/ Timothy K. Andrews, attorney-in-fact for Richard D. Peterson	07/26/2017
	** 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.
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