Activision in Santa Monica, California, founded on October 1, 1979, merged with Vivendi Games on July 9, 2008.
Beenox in Quebec, Canada, founded in May 2000, acquired on May 25, 2005.
Blizzard Entertainment in Irvine, California, founded in February 1991 as Silicon & Synapse, acquired in 1998 by Vivendi, merged with Activision on July 9, 2008.
DemonWare in both Dublin, Republic of Ireland, and Vancouver, British Columbia, Canada, founded in 2003, acquired on May 2007.
FreeStyleGames in Leamington, England, United Kingdom, founded in 2002, acquired September 12, 2008.
High Moon Studios in San Diego, California, founded as Sammy Entertainment in April 2001, acquired by Vivendi Games in January 2006.
Infinity Ward in Encino, California, founded in 2002, acquired October 2003.
Neversoft in Los Angeles, California, founded in July 1994, acquired October 1999.
Radical Entertainment in Vancouver, Canada, founded in 1991, acquired in 2005.
Raven Software in Madison, Wisconsin, founded in 1990, acquired in 1997.
Sledgehammer Games in Foster City, California, founded November 17, 2009
Toys For Bob in Novato, California, founded in 1989, acquired May 3, 2005.
Treyarch in Santa Monica, California, founded in 1996, acquired 2001.
Vicarious Visions in Albany, New York, founded in 1990, acquired January 2005.
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