Syniverse Holdings, Inc. 8125 Highwoods Palm Way Tampa, FL 33647 Attention: General Counsel Ladies and Gentlemen:

Exhibit 2.2

EXECUTION VERSION

October 2, 2009

Syniverse Holdings, Inc.
0000 Xxxxxxxxx Xxxx Xxx
Xxxxx, XX 00000
Attention: General Counsel

Ladies and Gentlemen:

Reference is made herein to the Acquisition Agreement by and among VERISIGN, INC., VERISIGN S.À.X.X., VERISIGN DO BRASIL SERVIÇOS PARA INTERNET LTDA, VERISIGN DIGITAL SERVICES TECHNOLOGY (CHINA) CO., LTD., VERISIGN SERVICES INDIA PRIVATE LIMITED (each, a “Seller Party”), and SYNIVERSE HOLDINGS, INC. (“Purchaser”), dated as of August 24, 2009 (the “Acquisition Agreement”). Capitalized terms used but not otherwise defined herein shall have the meanings set forth in the Acquisition Agreement.

Each Seller Party and Purchaser hereby agree to amend Section 1.01(ii)(a) of the Seller Disclosure Schedule by adding the following additional patent applications thereto, effective as of August 24, 2009:

Family No		Application No.		Patent Title		Grant Date		Patent No.		Notes
7		EP 07839732.0		A Method and Apparatus For Response Enabled Messaging						Annuity due 10/22/2009. BSTZ Ref. 6783.P087EP.
7		CA Not yet assigned		A Method and Apparatus For Response Enabled Messaging						Maintenance fee due 10/22/2010. BSTZ Ref. 6783.P087CA.

Except as specifically stated above, the Acquisition Agreement remains in full force and effect.

[Signature Pages Follow]

1

	Very truly yours, VERISIGN, INC.
	By:	/s/ Xxxxx X. Xxxxxx
		Name:	Xxxxx X. Xxxxxx
		Title:	SVP, Corp. & Strat. Development
	VERISIGN S.À.X.X.
	By:	/s/ Xxxxx X. Xxxxxx
		Name:	Xxxxx X. Xxxxxx
		Title:	Authorized Signatory
	VERISIGN DO BRASIL SERVIÇOS PARA INTERNET LTDA
	By:	/s/ Xxxxx X. Xxxxxx
		Name:	Xxxxx X. Xxxxxx
		Title:	Authorized Signatory
	VERISIGN DIGITAL SERVICES TECHNOLOGY (CHINA) CO., LTD.
	By:	/s/ Xxxxx X. Xxxxxx
		Name:	Xxxxx X. Xxxxxx
		Title:	Authorized Signatory
	VERISIGN SERVICES INDIA PRIVATE LIMITED
	By:	/s/ Xxxxx X. Xxxxxx
		Name:	Xxxxx X. Xxxxxx
		Title:	Authorized Signatory

2

Accepted and Agreed:
SYNIVERSE HOLDINGS, INC.
By:		/s/ Xxxx X. Xxxxxxxx
		Name: Xxxx X. Xxxxxxxx
		Title:   Chief Executive Officer

3