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 *
  LAMONT ANN H
2. Date of Event Requiring Statement (Month/Day/Year)
03/13/2014
3. Issuer Name and Ticker or Trading Symbol
CASTLIGHT HEALTH, INC. [CSLT]
(Last)
(First)
(Middle)
C/O OAK INVESTMENT PARTNERS, 3 PICKWICK PLAZA, SUITE 302
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)

GREENWICH, CT 06830
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)

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
Director Stock Option (right to buy)   (1) 03/12/2024 Class B Common Stock 25,000 $ 16 D  
Class A Common Stock   (2)(3)   (2)(3) Class B Common Stock (3) 122,232 $ 0 (2) (3) I See footnote (5)
Series A Convertible Preferred Stock   (4)   (4) Class A Common Stock (2) (3) 814,884 $ 0 (4) I See footnote (5)
Series A-1 Convertible Preferred Stock   (4)   (4) Class A Common Stock (2) (3) 653,582 $ 0 (4) I See footnote (5)
Series B Convertible Preferred Stock   (4)   (4) Class A Common Stock (2) (3) 8,522,522 $ 0 (4) I See footnote (5)
Series C Convertible Preferred Stock   (4)   (4) Class A Common Stock (2) (3) 1,459,460 $ 0 (4) I See footnote (5)
Series D Convertible Preferred Stock   (4)   (4) Class A Common Stock (2) (3) 345,064 $ 0 (4) I See footnote (5)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
LAMONT ANN H
C/O OAK INVESTMENT PARTNERS
3 PICKWICK PLAZA, SUITE 302
GREENWICH, CT 06830
  X      

Signatures

/s/ Ann H. Lamont 03/13/2014
**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) The stock option vests in 12 equal monthly installments beginning on April 13, 2014, until such time as the option is 100% vested, subject to the continuing service of the Reporting Person on each vesting date.
(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, pursuant to the Issuer's Restated Certificate of Incorporation (the "Post-Effective Certificate") that will be effective upon the consummation of the Issuer's initial public offering of its Class B Common Stock (the "IPO"), each share of Class A Common Stock will convert automatically into one (1) share of Class B Common Stock upon any 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 Post-Effective Certificate. The shares of Class A Common Stock have no expiration date.
(3) Pursuant to the Post-Effective Certificate, 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 falls below twenty percent of the number of shares of Class A common stock outstanding as of the closing of the IPO, (b) the ten year anniversary of the closing of the IPO, 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) Each share of Convertible Preferred Stock will be automatically converted into one (1) share of Class A Common Stock immediately prior to the consummation of the IPO, and has no expiration date.
(5) Represents securities directly owned by Oak Investment Partners XII, L.P and indirectly by Oak Associates XII, LLC, the sole general partner of Oak Investment Partners XII, L.P., and the Managing Members of Oak Associates XII, LLC. The "Managing Members" of Oak Associates XII, LLC are Ann H. Lamont, Bandel L. Carano, Edward F. Glassmeyer, Fredric W. Harman, Iftikar A. Ahmed, Grace A. Ames, Gerald R. Gallagher and Warren B. Riley. Such Managing Members have shared voting and investment control over all of the shares held by Oak Investment Partners XII, L.P.

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