Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
BOCK LOUIS C
  2. Issuer Name and Ticker or Trading Symbol
HORIZON PHARMA, INC. [HZNP]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O SCALE VENTURE MANAGEMENT II, LLC, 950 TOWER LANE, SUITE 700
3. Date of Earliest Transaction (Month/Day/Year)
08/02/2011
(Street)

FOSTER CITY, CA 94404
4. If Amendment, Date 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
(City)
(State)
(Zip)
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 08/02/2011   C   1,370,070 (1) A (1) 1,370,070 I See FN (2)
Common Stock 08/02/2011   C   171,626 (1) A (1) 1,541,696 I See FN (2)
Common Stock 08/02/2011   C   346,823 (3) A $ 9 1,888,519 I See FN (2)
Common Stock 08/02/2011   P   315,946 A $ 9 2,204,465 I See FN (2)

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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 Underlying Securities
(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 of Derivative Security: 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 Convertible Preferred Stock (1) 08/02/2011   C     3,252,547   (4)   (4) Common Stock 1,370,070 $ 0 0 I See FN (2)
Series B Convertible Preferred Stock (1) 08/02/2011   C     407,440   (4)   (4) Common Stock 171,626 $ 0 0 I See FN (2)
Convertible Promissory Notes $ 9 08/02/2011   C     $ 3,121,425.62   (5)   (5) Common Stock 346,823 $ 0 0 I See FN (2)
Warrant to Purchase Series A Preferred Stock $ 5.201 08/02/2011   C(6)     69,451   (7) 10/31/2015(7) Series A Preferred Stock 69,451 $ 0 0 I See FN (2)
Warrant to Purchase Series A Preferred Stock $ 5.201 08/02/2011   C(6)     34,726   (7) 07/02/2016(7) Series A Preferred Stock 34,726 $ 0 0 I See FN (2)
Warrant to Purchase Series A Preferred Stock $ 5.201 08/02/2011   C(6)     43,409   (7) 09/25/2016(7) Series A Preferred Stock 43,409 $ 0 0 I See FN (2)
Warrant to Purchase Common Stock $ 12.35 08/02/2011   C(6)   29,254     (7) 10/31/2015(7) Common Stock 29,254 $ 0 29,254 I See FN (2)
Warrant to Purchase Common Stock $ 12.35 08/02/2011   C(6)   14,627     (7) 07/02/2016(7) Common Stock 14,627 $ 0 14,627 I See FN (2)
Warrant to Purchase Common Stock $ 12.35 08/02/2011   C(6)   18,285     (7) 09/25/2016(7) Common Stock 18,285 $ 0 18,285 I See FN (2)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
BOCK LOUIS C
C/O SCALE VENTURE MANAGEMENT II, LLC
950 TOWER LANE, SUITE 700
FOSTER CITY, CA 94404
  X      

Signatures

 /s/ Louis Bock   08/04/2011
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) Automatic conversion, in connection with the Issuer's initial public offering, of preferred sock into shares of common stock. Every 2.374 shares of preferred stock converted into one share of common stock upon the closing of the Issuer's initial public offering.
(2) The securities are held directly by Scale Venture Partners II, LP ("Scale Partners"). The General Partner of Scale Partners is Scale Venture Management II, LLC ("Scale Management"). The reporting person is a member of Scale Management. The managing members of Scale Management share voting and investment power with respect to these shares. Each of the managing members of Scale Management disclaims beneficial ownership with respect to these securities except to the extent of his or her respective proportinate pecuniary interest therein.
(3) Represents shares acquired upon conversion, in connection with the Issuer's initial public offering, of convertible promissory notes.
(4) These securities are preferred stock of the Issuer and did not have an expiration date. Prior to the Issuer's initial public offering of common stock, the securities were convertible at any time at the election of the holder. The securities automatically converted into shares of common stock upon the closing of the issuer's initial public offering of common stock.
(5) Principal and accrued interest converted upon the Issuer's initial public offering of common stock, into shares of common stock.
(6) Automatic conversion, in connection with the Issuer's initial public offering, of warrants to purchase Series A Preferred Stock into warrants to purchase Common Stock. The warrants converted at a rate of 2.374 shares of Series A Preferred Stock to 1 share of Common Stock.
(7) The warrants are immediately exercisable and shall terminate on the earlier of the expiration date referenced herein or the occurence of other specified corporate transactions.

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