Pages where confidential treatment has been requested are stamped Confidential Treatment Requested and the Redacted Material has been separately filed with the Commission, and places where information has been redactedhave been marked with (***). EIGHTH AMENDMENT TO CSG MASTER SUBSCRIBER MANAGEMENT SYSTEM AGREEMENT

Exhibit 10.20G

Pages where confidential treatment has been requested are stamped “Confidential Treatment Requested and

the Redacted Material has been separately filed with the Commission,” and places where information has

been redacted have been marked with (***).

EIGHTH AMENDMENT

TO

CSG MASTER SUBSCRIBER MANAGEMENT SYSTEM AGREEMENT

BETWEEN

CSG SYSTEMS, INC.

AND

COMCAST CABLE COMMUNICATIONS MANAGEMENT, LLC

This Eighth Amendment (the “Amendment”) is made by and between CSG Systems, Inc., a Delaware corporation (“CSG”) and Comcast Cable Communications Management, LLC, a Delaware Limited Liability Company (“Customer”). CSG and Customer entered into a certain CSG Master Subscriber Management System Agreement dated March 17, 2004, and now desire to amend the Agreement in accordance with the terms and conditions set forth in this Amendment. If the terms and conditions set forth in this Amendment shall be in conflict with the Agreement, the terms and conditions of this Amendment shall control. Any terms in initial capital letters or all capital letters used as a defined term but not defined in this Amendment shall have the meaning set forth in the Agreement. Upon execution of this Amendment by the parties, any subsequent reference to the Agreement between the parties shall mean the Agreement as amended by this Amendment. Except as amended by this Amendment, the terms and conditions set forth in the Agreement shall continue in full force and effect according to their terms.

CSG and Customer agree as follows:

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IN WITNESS WHEREOF, the parties execute this Amendment on the date last signed below (“Effective Date”).

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