Warren Buffet
Famed investor Warren Buffett made his biggest donation to serval charities on Monday. He is pictured on Jan. 19, 2017 in New York City. Jamie McCarthy/Getty Images

Famed investor Warren Buffett donated $3.4 billion of his Berkshire Hathaway Inc. stock to five charities this week as part of his pledge to give away most of his wealth through philanthropy.

Buffett’s contributions went to charities ran by his family, including the Susan Thompson Buffett Foundation, Sherwood Foundation, Howard G. Buffett Foundation and NoVo Foundation, Berkshire Hathaway (BRK.A) said in a statement on Monday. This marks his most substantial charitable contribution to date.

The Bill and Melinda Gates Foundation, however, received the most significant chunk of the company's stock, totaling 13.5 million in shares worth roughly $2.6 billion, according to CNBC. The move is part of Buffett’s promise to give away most of his fortune to philanthropic causes.

Buffett, 87, has donated over $31 billion to these charities since 2006. About $24.5 billion of that was given to the Bill and Melinda Gates Foundation. That same year, Buffet announced plans to divest all his Berkshire shares to charity gradually and has since encouraged those with wealth to do the same.

"I’m not an enthusiast for dynastic wealth, particularly when 6 billion others have much poorer hands than we do in life,” Buffett said in 2007. "I believe in turning it over to people who are — and I’ve got five different organizations, including my three kids."

"I believe in turning it over to people who are energized, working hard at it, smart, you know, doing it with their own money, the whole thing."

In 2010, Gates and Buffett created the Giving Pledge, a campaign to encourage wealthy people to give money to philanthropic causes. Its contributors include Facebook CEO Mark Zuckerberg, his wife Pricilla Chan and Tesla founder and CEO Elon Musk, according to its website.

"More than 99 percent of my wealth will go to philanthropy during my lifetime or at death. Measured by dollars, this commitment is large. In a comparative sense, though, many individuals give more to others every day," Buffett wrote of his commitment,

Buffett is currently the third wealthiest person in the world with a net worth of about $83 billion, according to Bloomberg Billionaires Index. Gates comes in second with a net worth listed at $95.5 billion and Amazon’s Jeff Bezos is at the top with $150 billion.