Gerald Cavendish Grosvenor's fortune is valued at $12.3 billion in August 2016 by Bloomberg.

London-based Grosvenor Group, the property giant controlled by the Duke of Westminster, bounced back with a £395m profit last year and has built up a war chest of nearly £1 billion to return to global property markets. It plans to expand out of its traditional London stamping ground into Asia, especially China, and in November it spent £70m acquiring luxury properties in Scotland. A further boost to the 59-year-old duke's coffers has come in the group's scheme for 197 flats tucked behind Tate Modern on the Thames. Shares in the Grosvenor Group, which owns swathes of Mayfair, Belgravia and Knightsbridge are owned by trusts set up for the benefit of the Grosvenor family, which is headed by the 6th duke, who is the richest British-born member of our list but out of the top three for the first time since 1999. He stood down as chairman of the board in 2007 after 33 years but remains chairman of the trustees. The net asset value of the Grosvenor Group rose in 2010 to £2.78 billion. Adding Westminster's private estate assets outside the group, and with the top end of the London housing market looking healthier, we raise our valuation.

At age 64, Gerald Cavendish Grosvenor died on August 9, 2016 after suffering from a heart attack. He will be succeeded by his son Hugh Grosvenor as Duke of Westminster.