has joined a growing group of billionaire businessmen signing up to give away half their fortune during their lifetime with a commitment to the
Started by Bill Gates and Warren Buffett in 2010, there are now 105 billionaires who have made the philanthropic committment to the charities of their choice.
"As a young man, I never set out to make money," the Virgin boss wrote in his pledge letter. "We set out to create things that we could be proud of and try to make a difference."
Check out these other familiar faces to make the pledge, by Tara Prangell.
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Richard Branson's luxury retreats
Billionaires who will give their fortune away