He is a co-owner with Bill Gates of the Four Seasons Hotel management company.

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Seven years ago, in a Four Seasons Hotel van with Bill Gates, I became involved in a heated argument over Gil-der's perspicacity.

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The management company for the Four Seasons Hotel chain, which Alwaleed co-owns with Bill Gates, manages several hotels in England, including the Savoy, the Park Lane the Canary Wharf Four Seasons.

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His holdings include Citigroup, the Four Seasons Hotels (co-owned with Bill Gates), stakes in several Saudi companies, and large swaths of real estate in the Kingdom, among other holdings.

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Kingdom Holding owns stakes in Citigroup and other stocks in the U.S. and Saudi Arabia as well as real estate in Saudi Arabia and stakes in private companies like the Four Seasons Hotels (co-owned with Bill Gates) and the Fairmont hotels.

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Tucked behind two gates equipped with an automatic license plate recognition system, the four-story terraced home was constructed in the 1820s by architect Decimus Burton and overseen by John Nash, who designed nearby Regents Park.

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