This excerpt taken from the ATVI 8-K filed Jul 15, 2008.
The Merger. Activision and Vivendi Games combined their businesses through the merger of Merger Sub with and into Vivendi Games. As a result of the merger, Vivendi Games became a wholly-owned subsidiary of Activision. In the merger, VGAC, a subsidiary of Vivendi and the sole stockholder of Vivendi Games, received approximately 295.3 million newly issued shares of Activision common stock, which number is based upon a valuation of Vivendi Games at $8.121 billion and a per share price for Activision common stock of $27.50. Upon the closing of the Transactions, the combined company was renamed Activision Blizzard, Inc.