SEC FORM 4

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^*

MPM BIOVENTURES V, L.P.

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
ARATANA THERAPEUTICS, INC. [ PETX ]

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)
07/02/2013

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	07/02/2013		C		2,406,739⁽¹⁾	A	⁽²⁾	2,823,173⁽³⁾	I	See Footnote⁽⁴⁾
Common Stock	07/02/2013		C		802,246⁽⁵⁾	A	⁽²⁾	3,625,419	I	See Footnote⁽⁶⁾
Common Stock	07/02/2013		C		225,631⁽⁷⁾	A	⁽²⁾	3,851,050	I	See Footnote⁽⁸⁾
Common Stock	07/02/2013		P		500,000⁽⁹⁾	A	$6	4,351,050	I	See Footnote⁽¹⁰⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Series A Preferred Stock	⁽²⁾	07/02/2013		C			4,000,000⁽¹¹⁾	⁽¹²⁾	⁽¹³⁾	Common Stock	2,406,739⁽¹⁾	$0.00	0	I	See Footnote⁽¹¹⁾
Series B Preferred Stock	⁽²⁾	07/02/2013		C			1,333,333⁽¹⁴⁾	⁽¹²⁾	⁽¹³⁾	Common Stock	802,246⁽⁵⁾	$0.00	0	I	See Footnote⁽¹⁴⁾
Series C Preferred Stock	⁽²⁾	07/02/2013		C			375,000⁽¹⁵⁾	⁽¹²⁾	⁽¹³⁾	Common Stock	225,631⁽⁷⁾	$0.00	0	I	See Footnote⁽¹⁵⁾

1. Name and Address of Reporting Person^*

MPM BIOVENTURES V, L.P.

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

Scopa James Paul

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

601 GATEWAY BOULEVARD, SUITE 350

(Street)

SOUTH SAN FRANCISCO

94080

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

EVNIN LUKE

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

Foley Todd

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

GADICKE ANSBERT

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

KAILIAN VAUGHN M

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

MPM ASSET MANAGEMENT INVESTORS BV5 LLC

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

MPM BIOVENTURES V GP LLC

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

MPM BIOVENTURES V LLC

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT

200 CLARENDON STREET, 54TH FLOOR

(Street)

BOSTON

02116

(City)

(State)

(Zip)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. The shares are held as follows: 2,316,738 by MPM BioVentures V, L.P. ("BV V") and 90,001 by MPM Asset Management Investors BV5 LLC ("AM BV5"). MPM BioVentures V GP LLC and MPM BioVentures V LLC ("BV LLC") are the direct and indirect general partners of BV V and BV LLC is the manager of AM BV5. Ansbert Gadicke, Luke Evnin, Vaughn M. Kailian, James Paul Scopa, Todd Foley and John Vander Vort are the members of BV LLC. Mr. Vander Vort is a director of the Issuer and has separately filed a Form 4. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

2. Each share of Series A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock automatically converted into 0.6016847 of a share of Common Stock upon the closing of the Issuer's initial public offering without payment of further consideration. The shares had no expiration date.

3. Immediately prior to the closing of the Issuer's initial public offering, the Issuer issued shares of its Common Stock to the holders of its Series A, B and C Preferred Stock in satisfaction of accumulated and unpaid dividends. Includes the following shares: 226,794 by BV V and 9,135 by AM BV5.

4. The shares are held as follows: 2,717,287 by BV V and 105,886 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

5. The shares are held as follows: 772,246 by BV V and 30,000 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

6. The shares are held as follows: 3,489,533 by BV V and 135,886 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

7. The shares are held as follows: 217,194 by BV V and 8,437 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

8. The shares are held as follows: 3,706,727 by BV V and 144,323 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

9. The shares were purchased as follows: 481,302 by BV V and 18,698 by AM BV5.

10. The shares are held as follows: 4,188,029 by BV V and 163,021 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

11. The shares of Series A Preferred Stock were held as follows: 3,850,418 by BV V and 149,582 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

12. Immediately.

13. Not applicable.

14. The shares of Series B Preferred Stock were held as follows: 1,283,473 by BV V and 49,860 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

15. The shares of Series C Preferred Stock were held as follows: 360,977 by BV V and 14,023 by AM BV5. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

Remarks:

	By Ansbert Gadicke, member of MPM BioVentures V LLC, the managing member of MPM BioVentures V GP LLC, the general partner of MPM BioVentures V, L.P. /s/ Ansbert Gadicke	07/02/2013
	/s/ James Paul Scopa	07/02/2013
	/s/ Luke Evnin	07/02/2013
	/s/ Todd Foley	07/02/2013
	/s/ Ansbert Gadicke	07/02/2013
	/s/ Vaughn Kailian	07/02/2013
	By Ansbert Gadicke, member of MPM BioVentures V LLC, the manager of MPM Asset Management Investors BV5 LLC /s/ Ansbert Gadicke	07/02/2013
	By Ansbert Gadicke, member of MPM BioVentures V LLC, the managing member of MPM BioVentures V GP LLC /s/ Ansbert Gadicke	07/02/2013
	By Ansbert Gadicke, member of MPM BioVentures V LLC /s/ Ansbert Gadicke	07/02/2013
	** 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 4 (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).
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