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
OMB APPROVAL
OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
VENROCK ASSOCIATES V LP
  2. Issuer Name and Ticker or Trading Symbol
CASTLIGHT HEALTH, INC. [CSLT]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O VENROCK, 3340 HILLVIEW AVENUE
3. Date of Earliest Transaction (Month/Day/Year)
03/19/2014
(Street)

PALO ALTO, CA 94304
4. If Amendment, Date 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
(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

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

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 $ 0 (1) 03/19/2014   C     3,906,730   (1)   (1) Class A Common Stock (2) (3) 3,906,730 $ 0 0 I By Funds (4)
Series A-1 Convertible Preferred Stock $ 0 (1) 03/19/2014   C     6,630,686   (1)   (1) Class A Common Stock (2) (3) 6,630,686 $ 0 0 I By Funds (5)
Series B Convertible Preferred Stock $ 0 (1) 03/19/2014   C     3,617,117   (1)   (1) Class A Common Stock (2) (3) 3,617,117 $ 0 0 I By Funds (6)
Series C Convertible Preferred Stock $ 0 (1) 03/19/2014   C     924,373   (1)   (1) Class A Common Stock (2) (3) 924,373 $ 0 0 I By Funds (7)
Series D Convertible Preferred Stock $ 0 (1) 03/19/2014   C     303,650   (1)   (1) Class A Common Stock (2) (3) 303,650 $ 0 0 I By Funds (8)
Class A Common Stock $ 0 (2) (3) 03/19/2014   C   15,382,556 (1)     (2)(3)   (2)(3) Class B Common Stock (3) 15,382,556 $ 0 15,568,571 I By Funds (9)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
VENROCK ASSOCIATES V LP
C/O VENROCK
3340 HILLVIEW AVENUE
PALO ALTO, CA 94304
    X    
VENROCK PARTNERS V L P
C/O VENROCK
3340 HILLVIEW AVENUE
PALO ALTO, CA 94304
    X    
Venrock Entrepreneurs Fund V, L.P.
C/O VENROCK
3340 HILLVIEW AVENUE
PALO ALTO, CA 94304
    X    
Venrock Management V, LLC
C/O VENROCK
3340 HILLVIEW AVENUE
PALO ALTO, CA 94304
    X    
Venrock Partners Management V, LLC
C/O VENROCK
3340 HILLVIEW AVENUE
PALO ALTO, CA 94304
    X    
VEF Management V, LLC
C/O VENROCK
3340 HILLVIEW AVENUE
PALO ALTO, CA 94304
    X    

Signatures

 /s/ David L. Stepp, authorized signatory   03/19/2014
**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) In connection with the consummation of the Issuer's initial public offering (the "IPO") on March 19, 2014, each share of Convertible Preferred Stock automatically converted into one (1) share of Class A Common Stock for no additional consideration. All shares of Class A Common Stock issued upon conversion were aggregated.
(2) Each share of Class A Common Stock is convertible, at any time at the option of the holder, into one (1) share of Class B Common Stock. In addition, each share of Class A Common Stock will convert automatically into one (1) share of Class B Common Stock upon the transfer, whether or not for value, that occurs after the closing of the IPO to any transferee who is not a "Permitted Transferee", as defined in the Issuer's Restated Certificate of Incorporation in effect as of the date hereof. The shares of Class A Common Stock have no expiration date.
(3) Each share of the Issuer's Class A Common Stock will convert automatically into one (1) share of Class B Common Stock upon the earliest to occur of the following: (a) the first date on which the number of shares of Class A Common Stock then outstanding is less than 15,340,384 shares, (b) March 19, 2024, or (c) a time and date approved in writing by holders of at least a majority of the then-outstanding shares of Class A Common Stock. The shares of Class A Common Stock and Class B Common Stock have no expiration date.
(4) Venrock Associates V, L.P. ("VA5") held an aggregate of 3,525,043 shares, Venrock Partners V, L.P. ("VP5") held an aggregate of 298,865 shares and Venrock Entrepreneurs Fund V, L.P. ("VEF5") held an aggregate of 82,822 shares. Venrock Management V, LLC, VEF Management V, LLC and Venrock Partners Management V, LLC (collectively, the "Venrock GP Entities") are the sole general partners of VA5, VEF5 and VP5 (collectively, the "Funds"), respectively, and have voting and investment power over the shares held by the Funds. Each of the Venrock GP Entities disclaims beneficial ownership of the shares held by the Funds, except to the extent of their respective indirect pecuniary interests therein.
(5) VA5 held an aggregate of 5,982,868 shares, VP5 held an aggregate of 507,247 shares and VEF5 held an aggregate of 140,571 shares. The Venrock GP Entities are the sole general partners of the Funds, and have voting and investment power over the shares held by the Funds. Each of the Venrock GP Entities disclaims beneficial ownership of the shares held by the Funds, except to the extent of their respective indirect pecuniary interests therein.
(6) VA5 held an aggregate of 3,263,725 shares, VP5 held an aggregate of 276,710 shares and VEF5 held an aggregate of 76,682 shares. The Venrock GP Entities are the sole general partners of the Funds, and have voting and investment power over the shares held by the Funds. Each of the Venrock GP Entities disclaims beneficial ownership of the shares held by the Funds, except to the extent of their respective indirect pecuniary interests therein.
(7) VA5 held an aggregate of 834,062 shares, VP5 held an aggregate of 70,714 shares and VEF5 held an aggregate of 19,597 shares. The Venrock GP Entities are the sole general partners of the Funds, and have voting and investment power over the shares held by the Funds. Each of the Venrock GP Entities disclaims beneficial ownership of the shares held by the Funds, except to the extent of their respective indirect pecuniary interests therein.
(8) VA5 held an aggregate of 273,983 shares, VP5 held an aggregate of 23,230 shares and VEF5 held an aggregate of 6,437 shares. The Venrock GP Entities are the sole general partners of the Funds, and have voting and investment power over the shares held by the Funds. Each of the Venrock GP Entities disclaims beneficial ownership of the shares held by the Funds, except to the extent of their respective indirect pecuniary interests therein.
(9) VA5 holds an aggregate of 14,047,522 shares, VP5 holds an aggregate of 1,190,996 shares and VEF5 holds an aggregate of 330,053 shares. The Venrock GP Entities are the sole general partners of the Funds, and have voting and investment power over the shares held by the Funds. Each of the Venrock GP Entities disclaims beneficial ownership of the shares held by the Funds, except to the extent of their respective indirect pecuniary interests therein.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.