What is the name of the philanthropy pledge Warren Buffett co-founded with Bill Gates in 2010?

The philanthropy pledge Warren Buffett co-founded with Bill Gates in 2010 is The Giving Pledge.

The Giving Pledge is a campaign encouraging very wealthy people to commit at least half of their fortunes to charitable causes, either during their lifetimes or through their estates. It was formally announced in 2010 after Buffett and Bill Gates had spent time discussing how to encourage large-scale philanthropy among billionaires.

Melinda French Gates was also a founder and early organizer, so describing the initiative as something Buffett co-founded with Bill Gates is accurate but leaves out a third founder. The campaign is not the same as the Bill & Melinda Gates Foundation, which is a separate philanthropic organization that received major donations from Buffett.

The pledge is a public moral commitment rather than a legally enforceable contract. Signatories publish letters explaining their motivations, and the campaign's broader aim is to create a social norm around major charitable giving. That distinction explains why “Buffett Foundation” and “Gates-Buffett Foundation” are not the canonical answers.