This excerpt taken from the CVS 8-K filed Feb 13, 2007.
Business Combinations, CVS is treated as the acquiror of Caremark for accounting purposes. Accordingly, the combined company will allocate the purchase price paid by CVS to the fair value of the Caremark assets acquired and liabilities assumed. Due to legal restrictions, many of the details concerning individual assets and liabilities cannot be disclosed between CVS and Caremark prior to the mergers completion. Therefore, the pro forma presentation presumes that the historical value of Caremarks tangible assets and liabilities approximates fair value. Additionally, the allocation of purchase price to acquired intangible assets is preliminary and subject to the final outcome of independent analyses to be conducted after the completion of the merger. The residual amount of the purchase price has been allocated to goodwill. The actual amounts recorded when the merger is completed may differ materially from the pro forma amounts presented herein.