Ownership Submission
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, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  SIGAL ELLIOT
 2. Date of Event Requiring Statement (Month/Day/Year)
01/29/2015		 3. Issuer Name and Ticker or Trading Symbol
Spark Therapeutics, Inc. [ONCE]
(Last)
(First)
(Middle)
C/O SPARK THERAPEUTICS, INC., 3737 MARKET STREET, SUITE 1300		 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 Original Filed(Month/Day/Year)
(Street)

PHILADELPHIA, PA 19104		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
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)
Common Stock 6,214 (1)
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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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 of Derivative Security: 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)   (2) 06/10/2024 Common Stock 25,786 $ 3.45 D  
Stock Option (right to buy)   (3) 08/11/2024 Common Stock 17,203 $ 3.45 D  
Series B Preferred Stock   (5)(6)   (5)(6) Common Stock 31,056 $ (5) (6) I See footnote (4)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
SIGAL ELLIOT
C/O SPARK THERAPEUTICS, INC.
3737 MARKET STREET, SUITE 1300
PHILADELPHIA, PA 19104		   X      

Signatures

/s/ Joseph La Barge, as Attorney in Fact for Elliott Sigal 01/29/2015
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) These restricted shares were granted on February 25, 2014 and vest over four years, with 25% of the shares vesting on February 5, 2015, and the remainder vesting quarterly thereafter.
(2) This option was granted on June 10, 2014 and vests over four years, with 25% of the shares underlying the option vesting on February 5, 2015, and the remainder vesting quarterly thereafter.
(3) This option was granted on August 11, 2014 and vests over four years, with 25% of the shares underlying the option vesting on May 24, 2015, and the remainder vesting quarterly thereafter.
(4) These shares are held by Sigal Family Investments LLC. Elliott Sigal, a member of the issuer's board of directors, is a manager of Sigal Family Investments LLC and may be deemed to have voting and investment power over the shares held by Sigal Family Investments LLC. Dr. Sigal disclaims beneficial ownership of such shares except to the extent of any pecuniary interest therein.
(5) Consists of shares of Series B Preferred Stock issued on May 23, 2014, that are currently convertible into 31,056 shares of Common Stock. Shares of Series B Preferred Stock accrue stock dividends payable in additional shares of Series B Preferred Stock at a rate of 8% per annum from November 23, 2014. Shares of Series B Preferred Stock, including shares of Series B Preferred Stock issued as accrued stock dividends, are immediately convertible into shares of Common Stock upon issuance, will be automatically converted into shares of Common Stock immediately upon the closing of the issuer's initial public offering pursuant to a registration statement on Form S-1 under the Securities Act of 1933, as amended, and have no expiration date. The aggregate amount of stock dividends that will have accrued through February 4, 2015, the expected closing date of the initial public offering, is 503 shares of Common Stock. (Continued in Footnote 6.)
(6) The above Common Stock share equivalent numbers are rounded down to the nearest whole share number.
 
Remarks:
Exhibit Index:
24.1 Power of Attorney

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