SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549


SCHEDULE 13G/A


Under the Securities Exchange Act of 1934
(Amendment No. 4)


CASTLIGHT HEALTH, INC.
(Name of Issuer)


Class B Common Stock, $0.0001 par value per share
(Title of Class of Securities)


14862Q100
(CUSIP Number)


April 3, 2017
(Date of Event Which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)

* The  remainder of this cover page shall be filled out for a reporting  person’s initial filing on this form with respect to the subject class of securities, and for any  subsequent  amendment  containing  information  which  would  alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the  Securities  Exchange  Act of 1934 (the “Act”) or otherwise  subject to the liabilities of that section of the Act but shall be subject to all other  provisions of the Act  (however, see the Notes).



 


CUSIP No. 14862Q100
SCHEDULE 13G/A
Page 2 of 10 Pages

       
1)
Names of Reporting Persons
 
Maverick Capital, Ltd. – 75-2482446
2)
Check the Appropriate Box if a Member of a Group (See Instructions)
(a)         
(b)         
3)
SEC Use Only
 
4)
Citizenship or Place of Organization
 
Texas
Number of Shares
Beneficially Owned
by Each Reporting
Person With
(5)
Sole Voting Power
 
8,946,460(1)
(6)
Shared Voting Power
 
0
(7)
Sole Dispositive Power
 
8,946,460(1)
(8)
Shared Dispositive Power
 
0
9)
Aggregate Amount Beneficially Owned by Each Reporting Person
 
8,946,460(1)
10)
Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares
(See Instructions)          
 
11)
Percent of Class Represented in Amount in Row 9
 
10.6%
12)
Type of Reporting Person (See Instructions)
 
IA
(1)  Includes 7,733,386 shares of Class A Common Stock held by certain funds managed by Maverick Capital, Ltd. that are convertible at any time into shares of Class B Common Stock, options exercisable for 25,000 shares of Class B common stock and 43,750 shares of Class B common stock issuable upon the settlement of restricted stock units, held as of April 3, 2017 by Mr. David Singer on behalf of Maverick Capital, Ltd.
 


CUSIP No. 14862Q100
SCHEDULE 13G/A
Page 3 of 10 Pages

       
1)
Names of Reporting Persons
 
Maverick Capital Management, LLC – 75-2686461
2)
Check the Appropriate Box if a Member of a Group (See Instructions)
(a)          
(b)          
3)
SEC Use Only
 
4)
Citizenship or Place of Organization
 
Texas
Number of Shares
Beneficially Owned
by Each Reporting
Person With
(5)
Sole Voting Power
 
8,946,460(1)
(6)
Shared Voting Power
 
0
(7)
Sole Dispositive Power
 
8,946,460(1)
(8)
Shared Dispositive Power
 
0
9)
Aggregate Amount Beneficially Owned by Each Reporting Person
 
8,946,460(1)
10)
Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares
(See Instructions)          
 
11)
Percent of Class Represented in Amount in Row 9
 
10.6%
12)
Type of Reporting Person (See Instructions)
 
HC
(1)  Includes 7,733,386 shares of Class A Common Stock held by certain funds managed by Maverick Capital, Ltd. that are convertible at any time into shares of Class B Common Stock, options exercisable for 25,000 shares of Class B common stock and 43,750 shares of Class B common stock issuable upon the settlement of restricted stock units, held as of April 3, 2017 by Mr. David Singer on behalf of Maverick Capital, Ltd.
 


CUSIP No. 14862Q100
SCHEDULE 13G/A
Page 4 of 10 Pages

       
1)
Names of Reporting Persons
 
Lee S. Ainslie III
2)
Check the Appropriate Box if a Member of a Group (See Instructions)
(a)          
(b)          
3)
SEC Use Only
 
4)
Citizenship or Place of Organization
 
United States
Number of Shares
Beneficially Owned
by Each Reporting
Person With
(5)
Sole Voting Power
 
8,946,460(1)
(6)
Shared Voting Power
 
0
(7)
Sole Dispositive Power
 
8,946,460(1)
(8)
Shared Dispositive Power
 
0
9)
Aggregate Amount Beneficially Owned by Each Reporting Person
 
8,946,460(1)
10)
Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares
(See Instructions)          
 
11)
Percent of Class Represented in Amount in Row 9
 
10.6%
12)
Type of Reporting Person (See Instructions)
 
HC
(1)  Includes 7,733,386 shares of Class A Common Stock held by certain funds managed by Maverick Capital, Ltd. that are convertible at any time into shares of Class B Common Stock, options exercisable for 25,000 shares of Class B common stock and 43,750 shares of Class B common stock issuable upon the settlement of restricted stock units, held as of April 3, 2017 by Mr. David Singer on behalf of Maverick Capital, Ltd.
 


CUSIP No. 14862Q100
SCHEDULE 13G/A
Page 5 of 10 Pages

       
1)
Names of Reporting Persons
 
Andrew H. Warford
2)
Check the Appropriate Box if a Member of a Group (See Instructions)
(a)          
(b)          
3)
SEC Use Only
 
4)
Citizenship or Place of Organization
 
United States
Number of Shares
Beneficially Owned
by Each Reporting
Person With
(5)
Sole Voting Power
 
8,946,460(1)
(6)
Shared Voting Power
 
0
(7)
Sole Dispositive Power
 
8,946,460(1)
(8)
Shared Dispositive Power
 
0
9)
Aggregate Amount Beneficially Owned by Each Reporting Person
 
8,946,460(1)
10)
Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares
(See Instructions)          
 
11)
Percent of Class Represented in Amount in Row 9
 
10.6%
12)
Type of Reporting Person (See Instructions)
 
IN
(1)  Includes 7,733,386 shares of Class A Common Stock held by certain funds managed by Maverick Capital, Ltd. that are convertible at any time into shares of Class B Common Stock, options exercisable for 25,000 shares of Class B common stock and 43,750 shares of Class B common stock issuable upon the settlement of restricted stock units, held as of April 3, 2017 by Mr. David Singer on behalf of Maverick Capital, Ltd.

 
Item 1(a)
Name of Issuer:

Castlight Health, Inc.

Item 1(b)
Address of Issuer’s Principal Executive Offices:

Two Rincon Center
121 Spear Street, Suite 300
San Francisco, California  94105

Item 2(a)
Name of Person Filing:

This Schedule 13G (the “Schedule 13G”) is being filed on behalf of each of the following persons (each, a “Reporting Person”):

(i)
Maverick Capital, Ltd.;
(ii)
Maverick Capital Management, LLC;
(iii)
Lee S. Ainslie III (“Mr. Ainslie”); and
(iv)
Andrew H. Warford (“Mr. Warford”).

The Schedule 13G relates to Shares (as defined herein) held for the accounts of Maverick Capital, Ltd.’s clients.

Item 2(b)
Address of Principal Business Office or, if none, Residence:

The address of the principal business office of (i) Maverick Capital, Ltd. and Maverick Capital Management, LLC is 300 Crescent Court, 18th Floor, Dallas, Texas 75201, and (ii) Mr. Ainslie and Mr. Warford is 767 Fifth Avenue, 11th Floor, New York, New York 10153.

Item 2(c)
Citizenship:

(i)
Maverick Capital, Ltd. is a Texas limited partnership;
(ii)
Maverick Capital Management, LLC is a Texas limited liability company;
(iii)
Mr. Ainslie is a citizen of the United States; and
(iv)
Mr. Warford is a citizen of the United States.

Item 2(d)
Title of Class of Securities:

Class B Common Stock, $0.0001 par value per share (the “Shares”).

Item 2(e)
CUSIP Number:

14862Q100
Page 6 of 10


Item 3.
If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
 
(a)  Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).
 
(b)  Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
 
(c)  Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).
 
(d)  Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).
 
(e)  An investment advisor in accordance with §240.13d-1(b)(1)(ii)(E).
 
(f)  An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F).
 
(g)  A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G).
 
(h)  A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813).
 
(i)  A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3).
 
(j)  A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J);
 
(k)  Group, in accordance with § 240.13d-1(b)(1)(ii)(K).
 
If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution: _______________
 

Item 4
Ownership

Ownership as of April 3, 2017 is incorporated by reference to items (5) – (9) and (11) of the cover page of the Reporting Person.

Maverick Capital, Ltd. is an investment adviser registered under Section 203 of the Investment Advisers Act of 1940 and, as such, may be deemed to have beneficial ownership of the Shares which are the subject of this filing through the investment discretion it exercises over its clients’ accounts.  Maverick Capital Management, LLC is the General Partner of Maverick Capital, Ltd.  Mr. Ainslie is the manager of Maverick Capital Management, LLC.  Mr. Warford serves as the Chairman of the Stock Committee of Maverick Capital, Ltd.

Item 5
Ownership of Five Percent or Less of a Class

Not applicable.
 
Page 7 of 10

 
Item 6
Ownership of More than Five Percent on Behalf of Another Person.

Not applicable.

Item 7
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Not applicable.

Item 8
Identification and Classification of Members of the Group

Not applicable.

Item 9
Notice of Dissolution of Group

Not applicable.

Item 10
Certifications

By signing below each of the Reporting Persons certifies that, to the best of such person’s knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.
 
 

 
Page 8 of 10

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
 
 
Date:  May 10, 2017
MAVERICK CAPITAL, LTD.
 
           
 
By:
Maverick Capital Management, LLC,
 
   
Its General Partner
 
           
   
By:
Lee S. Ainslie III, Manager
 
           
     
By:
/s/ Anne K. Hill
 
       
Anne K. Hill
 
       
Under Power of Attorney dated
 
       
February 13, 2017
 
 
 
Date:  May 10, 2017
MAVERICK CAPITAL MANAGEMENT, LLC 
           
 
By:
Lee S. Ainslie III, Manager
 
           
   
By:
/s/ Anne K. Hill
 
     
Anne K. Hill
 
     
Under Power of Attorney dated
 
     
February 13, 2017
 
 
      
Date:  May 10, 2017
LEE S. AINSLIE III
 
     
           
 
By:
/s/ Anne K. Hill
 
   
Anne K. Hill
 
   
Under Power of Attorney dated
 
   
February 13, 2017
 
 
Date:  May 10, 2017
ANDREW H. WARFORD
 
     
           
 
By:
/s/ Anne K. Hill
 
   
Anne K. Hill
 
   
Under Power of Attorney dated
 
   
February 13, 2017
 
 
 
Page 9 of 10

 
EXHIBIT INDEX

A.
Joint Filing Agreement, dated February 17, 2015, by and among Maverick Capital, Ltd., Maverick Capital Management, LLC, Lee S. Ainslie III and Andrew H. Warford.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Page 10 of 10