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^*

Children's Hospital of Philadelphia Foundation

(Last)

(First)

(Middle)

3737 MARKET STREET

SUITE 1300

(Street)

PHILADELPHIA

19104

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
01/29/2015

3. Issuer Name and Ticker or Trading Symbol
Spark Therapeutics, Inc. [ ONCE ]

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

Director	X	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)
Common Stock	4,943,629	D

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	1,000,000	⁽¹⁾	D
Series B Preferred Stock	⁽²⁾	⁽²⁾	Common Stock	2,795,031	⁽²⁾	D
Accrued Preferred Stock Dividends	⁽³⁾	⁽³⁾	Common Stock	61,552	⁽³⁾	D
Stock Option (right to buy)	⁽⁴⁾	08/11/2024	Common Stock	37,203	$3.45	I	By Affiliate

Explanation of Responses:

1. The Series A Preferred Stock will automatically convert into Common Stock without payment of further consideration upon the closing of the Issuer's initial public offering and has no expiration date.

2. The Series B Preferred Stock will automatically convert into Common Stock without payment of further consideration upon the closing of the Issuer's initial public offering and has no expiration date.

3. The Series A Preferred Stock and Series B Preferred Stock accrue stock dividends payable in additional shares of Series A Preferred Stock or Series B Preferred Stock (respectively) at a rate of 8% per annum. Shares of Series A Preferred Stock and 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, 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 61,552 shares of Common Stock.

4. This option was granted on August 11, 2014 to Steven M. Altschuler, MD, the Chief Executive Officer of the Reporting Person and the Chairman of the Board of Directors of the Issuer. The option vests over four years, with 25% of the shares underlying the option vesting on May 24, 2015, and the remainder vesting quarterly thereafter. Dr. Altschuler holds this option for the benefit of the Reporting Person.

Remarks:

	Steven M. Altschuler, MD, Chief Executive Officer	01/29/2015
	** 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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