Stanley Fink, whose personal fortune is estimated at £120m, has been described as the "Godfather" of the hedge fund industry. He oversaw the growth of the Man Group to become one of the biggest players in the global market, before quitting as chief executive in 2007.
His timing – a year before the collapse of Lehman Brothers
triggered the worldwide financial crisis – was fortuitous, but was also partly driven by a life-changing personal experience.
While on holiday in Botswana in 2004, he was struck dumb mid-sentence and diagnosed with a brain tumour. He was back at work within three months of a successful operation to remove it, but wanted to devote more of his time to charity work and philanthropy. The 54-year-old now gives away one-third of his income to good causes, funding a children's hospital and building an academy school.
Lord Fink, who was ennobled two years ago, has also handed more than £2.5m to the Conservatives and bankrolled Boris Johnson's first campaign for the London mayoralty.
He spent two years as the party's Treasurer, returning to the position in March when Peter Cruddas resigned after being secretly taped telling journalists that a £250,000 donation would buy access to David Cameron.
The son of a grocer, Lord Fink read law at Cambridge but struggled to find a job with a law firm and instead embarked with stunning success on a career in finance.