UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

(Amendment No. 2)

(Mark One)

x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2015

OR

¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number 0-27512

CSG SYSTEMS INTERNATIONAL, INC.

(Exact name of registrant as specified in its charter)

Delaware	47-0783182
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

9555 Maroon Circle

Englewood, Colorado 80112

(Address of principal executive offices, including zip code)

(303) 200-2000

(Registrant’s telephone number, including area code)

Securities Registered Pursuant to Section 12(b) of the Act:

Title of Each Class	Name of Each Exchange on Which Registered
Common Stock, Par Value $0.01 Per Share	NASDAQ Stock Market LLC

Securities Registered Pursuant to Section 12(g) of the Act: None.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  x    No   ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ¨    No  x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    YES  x    NO  ¨

Indicate by a check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer”, “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer x Accelerated filer ¨ Non-accelerated filer ¨ Smaller reporting company ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes  ¨    No  x

The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant, computed by reference to the last sales price of such stock, as of the close of trading on June 30, 2015, was $1,004,123,083.

Shares of common stock outstanding at February 22, 2016: 32,332,186

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant's Proxy Statement for its 2016 Annual Meeting of Stockholders to be filed on or prior to April 29, 2016, are incorporated by reference into Part III of the Form 10-K.

CSG SYSTEMS INTERNATIONAL, INC.

2015 FORM 10-K/A (Amendment No. 2)

TABLE OF CONTENTS

		Page
PART IV
Item 15.	Exhibits, Financial Statement Schedules	3
	Signatures	4

Explanatory Note

CSG Systems International, Inc. (the “Company” or forms of the pronoun “we”) is filing this Amendment No. 2 on Form 10-K/A for the year ended December 31, 2015, as originally filed with the Securities and Exchange Commission on February 26, 2016 (the “Original Filing”), and amended by Amendment No. 1 on Form 10-K/A filed with the Commission on March 1, 2016 (“Amendment No. 1”), for the sole purpose of refiling a revised, redacted version of Exhibit 10.24AZ to address comments received from the Commission in connection with its review of the Company’s confidential treatment request for certain portions of Exhibit 10.24AZ.   Exhibit 10.24AZ has been revised to only redact those words and phrases for which confidentiality is necessary and supported by the Freedom of Information Act and applicable Commission rules. Specifically, certain words and phrases in section 1 (a) and (b) of Exhibit 10.24 AZ, that were redacted in the Original Filing are now filed in non-redacted form.

No other changes have been made to the Original Filing or any other exhibits. This Amendment speaks as of the filing date of the Original Filing and does not reflect events occurring after the filing date, or modify or update those disclosures that may be affected by subsequent events. As such, this Form 10–K/A should be read in conjunction with the Original Filing and Amendment No. 1 to the Original Filing.

2

PART IV

Item  15. Exhibits, Financial Statement Schedules

(a) Financial Statements, Financial Statement Schedules, and Exhibits:

(1) Financial Statements

The financial statements filed as part of this report are listed on the Index to Consolidated Financial Statements on page 39 of the Original Filing.

(2) Financial Statement Schedules:

None. Any information required in the Financial Statement Schedules is provided in sufficient detail in our Financial Statements and notes thereto.

(3) Exhibits

Exhibits are listed in the Exhibit Index on page 5.

The Exhibits include management contracts, compensatory plans and arrangements required to be filed as exhibits to the Form 10-K by Item 601 of Regulation S-K.

(b) Exhibits

The Exhibits filed or incorporated by reference herewith are as specified in the Exhibit Index.

3

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

CSG SYSTEMS INTERNATIONAL, INC.
By:	/s/ ROLLAND B. JOHNS
	Rolland B. Johns
	Chief Accounting Officer
	(Principal Accounting Officer)
Date: August 29, 2016

4

EXHIBIT INDEX

Exhibit Number	Description
2.10 (16)	Implementation Agreement between CSG Systems International, Inc. and Intec
3.01 (1)	Restated Certificate of Incorporation of the Company
3.02 (38)	Amended and Restated Bylaws of CSG Systems International, Inc.
3.03 (2)	Certificate of Amendment of Restated Certificate of Incorporation of CSG Systems International, Inc.
4.01 (1)	Form of Common Stock Certificate
4.40 (13)	Indenture dated March 1, 2010 between CSG Systems International, Inc. and The Bank of New York Mellon Trust Company, N.A., as trustee
4.60 (27)	$250,000,000 Amended and Restated Credit Agreement dated as of November 9, 2012, among CSG Systems International, Inc., as Borrower, The Guarantors Party Hereto, The Lenders Party Hereto, RBC Capital Markets, Wells Fargo Securities, LLC, HSBC Bank USA, National Association and BBVA Compass, as Join Lead Arrangers and Joint Bookmanagers, Wells Fargo Bank, National Association, as Syndication Agent, HSBC Bank USA, National Association and BBVA Compass, as Co-Documentation Agents, Royal Bank of Canada, as Administrative Agent and Collateral Agent, and Royal Bank of Canada, as Issuing Bank and Swingline Lender
4.70 (39)	$350,000,000 Second Amended and Restated Credit Agreement dated as of February 3, 2015, among CSG Systems International, Inc., as Borrower, The Guarantors Party Hereto, The Lenders Party Hereto, RBC Capital Markets, Wells Fargo Securities, LLC, HSBC Bank USA, National Association, BBVA, and Merrill Lynch, Pierce, Fenner & Smith Incorporated as Joint Lead Arrangers and Joint Bookmanagers; Wells Fargo Bank, National Association as Syndication Agent; HSBC Bank USA, National Association, BBVA Compass, and Bank of America, N.A. as Co-Documentation Agents; Royal Bank of Canada as Administrative Agent and Collateral Agent, and Royal Bank of Canada as Issuing Bank and Swingline Lender
10.02 (19)	Second Amended and Restated 1996 Employee Stock Purchase Plan, as adopted on May 17, 2011
10.04 (34)	CSG Systems International, Inc. 2005 Stock Incentive Plan, as adopted on May 22, 2014
10.05 (19)	CSG Systems International, Inc. Performance Bonus Program, as adopted on May 17, 2011
10.06 (7)	CSG Systems International, Inc. 2001 Stock Incentive Plan, as amended August 14, 2007
10.10* (42)	Fixed Notional Accelerated Share Repurchase Transaction between CSG Systems International, Inc. and RBC Capital Markets LLC, as agent for Royal Bank of Canada
10.15 (14)	Form of Indemnification Agreement between CSG Systems International, Inc. and Directors and Executive Officers
10.16 (4)	Indemnification Agreement between CSG Systems International, Inc. and Mr. Ronald Cooper, dated November 16, 2006
10.21* (9)	CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21A* (17)	Fifth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21B* (18)	Sixth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21C* (20)	Seventh Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21D* (25)	Eighth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC

5

Exhibit Number	Description
10.21E* (25)	Ninth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21F* (25)	Tenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21G* (25)	Eleventh Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21H* (25)	Twelfth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21I* (26)	Thirteenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21J* (26)	Fourteenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21K* (26)	Fifteenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21L* (26)	Sixteenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21M* (27)	Seventeenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21N* (27)	Eighteenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21O* (27)	Twentieth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21P* (28)	Nineteenth Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21Q* (28)	Twenty-First Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21R* (28)	Twenty-Second Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.21S* (28)	Twenty-Third Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22* (28)	CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22A* (29)	First Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22B* (30)	Second Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22C* (30)	Third Amendment to the Restated and Amended CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22D* (30)	Fourth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22E* (31)	Fifth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC

6

Exhibit Number	Description
10.22F* (31)	Sixth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22G* (31)	Seventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22H* (32)	CD Addendum to CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22I* (37)	Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22J* (37)	Tenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22K* (39)	Eleventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22L* (39)	Twelfth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22M* (39)	Thirteenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22N* (40)	Fourteenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22O* (40)	Fifteenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22P* (41)	Sixteenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22Q* (43)	Seventeenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22R* (46)	Eighteenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.22S* (46)	Nineteenth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Comcast Cable Communications Management, LLC
10.23* (12)	CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Dish Network L.L.C.
10.23A* (14)	Third Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Dish Network, L.L.C.
10.23B* (17)	Fourth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Dish Network, L.L.C.
10.23C* (18)	Tenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and DISH Network, L.L.C.
10.23D* (20)	Eleventh Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23E* (20)	Twelfth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23F* (20)	Thirteenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23G* (20)	Fourteenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C

7

Exhibit Number	Description
10.23H* (21)	Fifteenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23I* (25)	Sixteenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23J* (24)	Seventeenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23K* (24)	Eighteenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23L* (23)	Nineteenth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23M* (24)	Twentieth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23N* (24)	Twenty-first Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23O* (35)	Twenty-second Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23P* (25)	Twenty-third Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23Q* (25)	Twenty-fourth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23R* (26)	Twenty-fifth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23S* (26)	Twenty-sixth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23T* (27)	Twenty-seventh Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23U* (27)	Twenty-eighth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23V* (27)	Twenty-ninth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23W* (27)	Thirtieth Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Dish Network L.L.C.
10.23X* (29)	Thirty-First Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23Y* (29)	Thirty-Second Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23Z* (29)	Thirty-Third Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AA* (29)	Thirty-Fourth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AB* (30)	Thirty-Fifth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AC* (30)	Thirty-Sixth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.

8

Exhibit Number		Description
10.23AD* (31)		Thirty-Seventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AE* (31)		Thirty-Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AF* (33)		Fortieth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AG* (33)		Forty-First Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AH* (37)		Forty-Second Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AI* (37)		Forty-Third Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AJ* (37)		Forty-Fourth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AK* (37)		Forty-Fifth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AL* (37)		Forty-Sixth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AM* (39)	Forty-Seventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AN* (41)		Forty-Eighth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.23AO* (43)		Forty-Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.24AP* (43)		Fiftieth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and DISH Network L.L.C.
10.24* (11)		CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable dated March 13, 2003
10.24A* (11)		ComTec Processing and Production Services Agreement
10.24B* (11)		Second Amendment to the Processing and Production Services Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24C* (17)		Forty-ninth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24D* (20)		Third Amendment to the Processing and Production Services Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24E* (20)		Fifty-First Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24F* (20)		Fifty-Third Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24G* (25)		Fifty-Seventh Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24H* (25)		Sixty-First Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.

9

Exhibit Number	Description
10.24I*(26)	Fifty-Sixth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24J* (26)	Sixty-third Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24K* (26)	Sixty-fifth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24L* (27)	Forty-eighth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24M* (27)	Fifty-ninth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24N* (27)	Sixty-seventh Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24O* (27)	Sixty-eighth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24P (27)	Second Amendment to Affiliate Addendum (Corporate National Sales Division)
10.24P* (28)	Sixtieth Amendment to the CSG Master Subscriber Management Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24Q (27)	Fourth Amendment to Affiliate Addendum Carolina Region
10.24Q* (28)	Seventieth Amendment to the CSG Master Subscriber Management Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24R (28)	First Amendment to Affiliate Addendum Media Sales Division between CSG Systems, Inc. and Time Warner Cable Inc.
10.24S* (29)	Sixty-Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24T* (30)	Seventy-Third Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24U* (30)	Seventy-Sixth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24V* (31)	Fifty-Eighth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24W* (31)	Seventy-Second Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24X* (31)	Seventy-Fifth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24Y* (31)	Seventy-Seventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24Z* (31)	Eighty-Second Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AA* (33)	Seventy-Fourth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AB* (33)	Seventy-Eighth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AC* (33)	Seventy-Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.

10

Exhibit Number		Description
10.24AD* (35)		Eighty-First Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AE* (35)		Eighty-Third Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AF* (35)		Eighty-Fourth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AG* (35)		Eighty-Fifth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AH* (36)		Amended and Restated Processing and Production Services Agreement entered into between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AI* (37)		Eighty-Seventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AJ* (37)		Eighty-Eighth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AK* (37)		Eighty-Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AL* (37)		Ninetieth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AM* (37)		Ninety-First Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AN* (40)		Eighty-Sixth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AO* (39)		First Amendment to the CSG Master Subscriber Management System Agreement Between CSG Systems, Inc. and Time Warner Cable Enterprises LLC
10.24AP* (40)		Second Amendment to the Amended and Restated Processing and Production Services Agreement Between CSG Systems, Inc. and Time Warner Cable Enterprises LLC
10.24AQ* (40)	Ninety-Fifth Amendment of the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AR* (41)	Ninety-Seventh Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AS* (41)	Ninety-Eighth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AT* (43)	Third Amendment to the Amended and Restated Processing and Production Services Agreement between CSG Systems, Inc. and Time Warner Cable Enterprises LLC
10.24AU* (43)	Ninety-Second Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AV* (43)	Ninety-Sixth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AW* (46)	Ninety-Ninth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AX* (46)	One Hundredth Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.24AY* (46)	One Hundred-First Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.

11

Exhibit Number		Description
10.24AZ*	One Hundred-Third Amendment to the CSG Master Subscriber Management System Agreement between CSG Systems, Inc. and Time Warner Cable Inc.
10.39 (9)	CSG Systems, Inc. Wealth Accumulation Plan, as amended August 15, 2008
10.47 (8)		Restated Employment Agreement with Randy R. Wiese, dated May 29, 2008
10.47A (9)		First Amendment to Restated Employment Agreement with Randy R. Wiese, dated August 19, 2008
10.47B (45)		Amended and Restated Employment Agreement with Randy R. Wiese, dated November 30, 2015
10.48 (8)		Restated Employment Agreement with Peter E. Kalan, dated May 29, 2008
10.48A (9)		First Amendment to Restated Employment Agreement with Peter E. Kalan, dated August 19, 2008
10.48B (44)		Resignation and Retirement Agreement with Peter E. Kalan, dated November 19, 2015
10.49 (8)		Restated Employment Agreement with Joseph T. Ruble, dated May 29, 2008
10.49A (9)		First Amendment to Restated Employment Agreement with Joseph T. Ruble, dated August 19, 2008
10.49B (45)		Amended and Restated Employment Agreement with Joseph T. Ruble, dated November 30, 2015
10.50 (3)		CSG Systems International, Inc. 2001 Stock Incentive Plan
10.51 (10)		Employment Agreement with Bret C. Griess dated February 19, 2009
10.51A (44)		Amended and Restated Employment Agreement with Bret C. Griess, dated November 19, 2015
10.80A (6)		Forms of Agreement for Equity Compensation
10.80B (5)		Forms of Agreement for Equity Compensation
10.81 (9)		Forms of Agreement for Equity Compensation
10.82 (18)		Forms of Agreement for Equity Compensation
10.83 (28)		Forms of Agreement for Equity Compensation
10.83A (30)		Forms of Agreement for Equity Compensation
21.01 (46)		Subsidiaries of the Registrant
23.01 (46)		Consent of KPMG LLP
31.01(47)		Certifications Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
31.01A		Certifications Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
31.02 (46)		Certifications Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
31.02A		Certifications Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
32.01 (46)		Certification pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
101.INS (46)		XBRL Instance Document
101.SCH (46)		XBRL Taxonomy Extension Schema Document
101.CAL (46)		XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF(46)		XBRL Taxonomy Extension Definition Linkbase Document
101.LAB (46)		XBRL Taxonomy Extension Label Linkbase Document
101.PRE (46)		XBRL Taxonomy Extension Presentation Linkbase Document

(1) Incorporated by reference to the exhibit of the same number to the Registration Statement No. 333-244 on Form S-1.

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(2) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 1997.  

(3) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2002.

(4) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated November 16, 2006.

(5) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2007.

(6) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2007.

(7) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2007.

(8) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2008.

(9) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2008.

(10) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2009.

(11) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K/A for the year ended December 31, 2008, filed on September 8, 2009.

(12) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2009.

(13) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated February 24, 2010.

(14) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2010.

(15) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated July 13, 2010.

(16) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2010.

(17) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2010.

(18) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2011.

(19) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated May 17, 2011.

(20) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2011.

(21) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2011.

(22) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2011.

(23) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2012.

(24) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q/A for the period ended March 31, 2012, filed on August 29, 2012.

(25) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2012.

(26) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2012.

(27) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2012.

(28) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2013.

(29) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2013.

(30) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2013.

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(31) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2013.  

(32) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-K/A for the period ended December 31, 2013, filed on July 9, 2014.

(33) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2014.

(34) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated May 22, 2014.

(35) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2014.

(36) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q/A for the period ended June 30, 2014, filed on October 23, 2014.

(37) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2014.

(38) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated November 20, 2014.

(39) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2014.

(40) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2015.

(41) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended June 30, 2015.

(42) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q/A for the period ended March 31, 2015, filed on September 18, 2015.

(43) Incorporated by reference to the exhibit of the same number to the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2015.

(44) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K for the event dated November 19, 2015.

(45) Incorporated by reference to the exhibit of the same number to the Registrant’s Current Report on Form 8-K/A for the event dated November 19, 2015, filed on December 1, 2015.

(46) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K for the year ended December 31, 2015.

(47) Incorporated by reference to the exhibit of the same number to the Registrant’s Annual Report on Form 10-K/A for the year ended December 31, 2015, filed on March 1, 2016.

* Portions of the exhibit have been omitted pursuant to an application for confidential treatment, and the omitted portions have been filed separately with the Commission.

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