Paul Gardner Allen (January 21, 1953 – October 15, 2018) was an American business magnate, investor, and philanthropist. Allen co-founded Microsoft with Bill Gates. In March 2018, Allen was estimated to be the 44th-wealthiest person in the world according to the Forbes annual list of the world's billionaires, with an estimated net worth of $21.7 billion, revised at the time of his death to $20.3 billion. He was the founder and chairman of Vulcan Inc., which managed his business and philanthropic efforts. Allen also had a multi-billion dollar investment portfolio which included technology companies such as Evri and Gist, real estate holdings, and stakes in other technology, media, and content companies. Allen also owned two professional sports teams, the Seattle Seahawks of the National Football League (NFL), and the Portland Trail Blazers of the National Basketball Association (NBA). He was also part-owner of the Seattle Sounders FC, which joined Major League Soccer (MLS) in 2009. Allen's memoir Idea Man: A Memoir by the Cofounder of Microsoft was released on April 19, 2011.

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