VeriSign (VRSN)

ARRANGEMENT AGREEMENT

THIS ARRANGEMENT AGREEMENT dated as of January 23, 2009,

B E T W E E N:

VeriSign, Inc., a corporation incorporated under the laws of the State of Delaware (the “Acquiror”)

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Certicom Corp., a corporation continued under the laws of Canada (“Certicom” or the “Company”)

WHEREAS upon the terms and subject to the conditions of this Arrangement Agreement, the Parties hereto intend to propose the Arrangement;

WHEREAS Certicom wishes to support and facilitate the Arrangement on the terms and subject to the conditions set forth in this Arrangement Agreement and the Board has concluded that it is in the best interests of Certicom to consummate the Arrangement, on the terms and subject to the conditions set forth in this Arrangement Agreement, in which Certicom would become a wholly-owned subsidiary of the Acquiror, and the Board has unanimously approved this Arrangement Agreement and intends to recommend that the Arrangement Resolution be approved by the Certicom Shareholders, on the terms and subject to the conditions of this Arrangement Agreement;

WHEREAS the Acquiror and Certicom desire to make certain representations, warranties, covenants and agreements in connection with the Arrangement and also to prescribe various conditions to the Arrangement;

NOW, THEREFORE, in consideration of the foregoing and the respective representations, warranties, covenants and agreements set forth herein, the Parties hereto agree as follows: