A nonprofit organization that encourages people across the economic spectrum to explore philanthropic collaborations and consider how they can give a higher proportion of their assets was a key inspiration for the Warren Buffett and Bill and Melinda Gates Giving Pledge, The Seattle Times writes.

Melinda Gates has credited Bolder Giving, started in 2007 by Boston couple Anne and Christopher Ellinger, with being an impetus behind the campaign to persuade the world’s billionaires to commit at least half of their fortunes to charity.

The organization received a $675,000 grant from the Bill & Melinda Gates Foundation in May, two months before the pledge campaign was announced.

Two writers for the political site RedBlueAmerica.com debate conservative criticism of the Giving Pledge in a column for Scripps Howard News Service.