17. Business Combinations Acquisitions Vet Therapeutics On October 15, 2013, the Company acquired Vet Therapeutics, a San Diego, California based company with a proprietary antibody-based biologics platform. This acquisition further expanded the existing Company pipeline and will significantly accelerate Aratana s pathway toward becoming a commercial-stage pet therapeutics company. The preliminary aggregate purchase price was approximately $51,515, which consisted of $30,005 in cash, 624,997 shares of Aratana s common stock with an acquisition date fair value of $14,700, a promissory note in the principal amount of $3,000 with a maturity date of December 31, 2014, and a contingent consideration of up to $5,000 with an acquisition fair value of $3,810. The promissory note bears interest at a rate of 7% per annum, payable quarterly in arrears, and is subject to prepayment in the event of specified future equity financings by the Company. The Company could have to pay up to $5,000 in contingent cash consideration in connection with the achievement of certain regulatory and manufacturing milestones for AT-004. Included in the Company s consolidated statements of operations for the year end December 31, 2013 is revenue totaling approximately $123 related to Vet Therapeutics. The amount of goodwill from this acquisition is not deductible for tax purposes. The acquisition date fair value of the consideration transferred to the sellers of Vet Therapeutics, less cash acquired, was $51,503, which consisted of the following: Cash consideration $ 30,005 Fair value of Merger Shares 14,700 Fair value of promissory note 3,000 Fair value of contingent consideration 3,810 Fair value of total consideration 51,515 Less cash acquired (12 ) Total consideration transferred, net of cash acquired $ 51,503 Fair Value of Merger Shares : The Company agreed to transfer 624,997 unregistered shares of its common stock without registration rights to former Vet Therapeutics stock and option holders. On October 15, 2013, the closing date of the