Buffett, chairman and CEO of Berkshire Hathaway Inc., said in a letter introducing the concept that he couldn't be happier with his decision in 2006 to give 99 percent of his roughly $46 billion fortune to charity.
Patty Stonesifer, former CEO of the Bill & Melinda Gates Foundation, told The Associated Press on Wednesday that Gates and Buffett have been campaigning for the past year to get others to donate the bulk of their wealth.
The friends and philanthropic colleagues are asking people to pledge to donate either during their lifetime or at the time of their death. They estimate their efforts could generate $600 billion dollars in charitable giving. In 2009, American philanthropies received a total of about $300 billion in donations, according to The Chronicle of Philanthropy.
The handful of billionaires approached so far have embraced the campaign, said Stonesifer, a close friend of Gates who offered to speak about the effort. Four wealthy couples have already announced their pledges, including Los Angeles philanthropists Eli and Edythe Broad, Gerry and Marguerite Lenfest of Philadelphia, John and Ann Doerr of Menlo Park, Calif., and John and Tashia Morgridge of San Jose, Calif.
In addition to making a donation commitment, Gates and Buffett are asking billionaires to pledge to give wisely and learn from their peers. They said they were inspired by the philanthropic efforts of not just other billionaires but of the people of all financial means and backgrounds who have given generously to make the world a better place.
Their philosophical forebears are the Carnegie and Rockefeller families, who donated most of their wealth back to improve society and were the grandparents of modern philanthropy, said Stacy Palmer, editor of The Chronicle of Philanthropy.
Ted Turner's announcement 13 years ago of a $1 billion gift to United Nations programs also was done in part to inspire other big givers, but did not have a noticeable result, Palmer said.
"It's a stretch to see how they're going to get to the $600 billion figure," she said, noting that only 17 people on the Forbes list of the 400 wealthiest people in America are also on the Chronicle's list of the most generous American donors.
Many of these people may be giving anonymously or plan to donate when they die, but the bulk of money raised by charities today comes from non-billionaires giving $5, $10 or $50 at a time, Palmer said.
Buffett's plan will eventually split most of his shares of his Omaha, Neb., company between five charitable foundations, with the largest chunk going to the Gates Foundation. He also plans to give Class B Berkshire shares to the Susan Thompson Buffett Foundation, which he and his late first wife started, and to the three foundations run by his three children.
Buffett said in 2006 that his other 73,332 Class A shares of Berkshire stock, worth about $8 billion, would also go to philanthropy, but he didn't specify how those shares would be distributed.
Bill and Melinda Gates have made a similar pledge through the establishment of their Seattle-based foundation.
Gates and Buffett are asking each individual or couple who make a pledge to do so publicly, with a letter explaining their decision.
"The pledge is a moral commitment to give, not a legal contract. It does not involve pooling money or supporting a particular set of causes or organizations," they explain in a written statement about the project.
