The 40 names that have pledged to date have a combined net worth surpassing $230 billion, according to Forbes. Several of them have said they plan to give away much more than 50% of their wealth. Buffett has promised to donate more than 99% of his wealth. In addition to Buffett and Gates, America's two richest men with a combined net worth of $90 billion, according to Forbes — 38 other billionaires have signed The Giving Pledge and include the following people:
Others include New York Mayor Michael Bloomberg, entertainment executive Barry Diller, Oracle co-founder Larry Ellison, energy tycoon T. Boone Pickens, media mogul Ted Turner, David Rockefeller, film director George Lucas and investor Ronald Perelman.
"We're off to a terrific start," Buffett, co-founder and chairman and CEO of Berkshire Hathaway, said in a conference call also attended by Bloomberg and San Francisco hedge-fund manager Tom Steyer and his wife Kat Taylor, founder of OneCalifornia Bank.
Buffett said he and Gates, the Microsoft co-founder, and Gates' wife Melinda made calls to fellow billionaires on the Forbes 400 list of wealthiest Americans — in many cases, people they had never met — to try to persuade them to join the giving pledge.
"We contacted between 70 and 80 people to get the 40. A few were unavailable. We don’t give up on them. Every saint has a past, every sinner has a future. We’ll keep on working," Buffett said.
Bloomberg, who made the bulk of his estimated $17.5 billion fortune from financial news and information services company Bloomberg L.P., said it didn't make sense to leave everything to his children and have them go through life as members of "the lucky sperm club."
"You don’t want to leave them so much money that it ruins their lives," Bloomberg said. "You want kids who can look back and say, 'Yeah my family helped me but I did something on my own.'"
Added Steyer: "We need to support each other. I look at this as replanting your garden so that future generations will have a full bounty of crops."
The pledge is a moral commitment to give, not a legal contract. It does not involve pooling money or supporting one cause or organization. It's up to each person who signs the pledge how to divvy up their wealth.
In letters on the givingpledge.org website, the 40 billionaires explain what motivated them to follow in the footsteps of Gates and Buffett.
"I’m particularly thankful for my father’s advice to set goals so high that they can’t possibly be achieved during a lifetime and to give help where help is needed most," CNN founder Ted Turner said. "That inspiration keeps me energized and eager to keep working hard every day on giving back and making the world a better place for generations to come.”
“My pledge is to the process; as long as I have the resources at my disposal, I will seek to raise the bar for future generations of students of all ages," filmmaker George Lucas said. "I am dedicating the majority of my wealth to improving education.”
Gates and Buffett hatched the idea of a giving campaign in mid-2009 at a secret dinner meeting in New York with a few select billionaires. The campaign went public this June.
Buffett acknowledged that some wealthy people may find it beneficial to donate more so they can avoid or write off more taxes. But he said that's not the reason billionaires are taking the pledge.
"Of the 20 or so people that I have talked to that have signed, not one of them has talked to me about taxes," Buffett said.
"It may be a consideration but I think the motivation goes far, far beyond taxes."
And of the billionaires contacted who didn't join the pledge?
"There were a few people who gave answers that indicated their various dissatisfaction with government," Buffett said. "A few had dynastic ideas about wealth … an intergenerational compact with family to keep that going. And there were others who said, 'I’ve got a plane to catch and I'll have to hang up.'"