Amount donated in 2013: $225-million
Beneficiaries: HopeLab, Humanity United, Omidyar Network, and the Ulupono Initiative
Background: Mr. Omidyar founded the online auction company, eBay, in San Jose, Calif. Ms. Omidyar is chairwoman of HopeLab, a Redwood City, Calif., nonprofit that develops technology to help critically ill children.
The Omidyars, who are both 46, gave $225-million to HopeLab; Humanity United, a nonprofit that supports efforts to fight slavery and mass atrocities around the globe; the nonprofit arm of the Omidyar Network; and the nonprofit branch of the Ulupono Initiative, a Honolulu organization that supports groups focused on the environment, local agriculture, and sustainable energy.
The Philanthropy 50: Browse the full list of America's most generous donors in 2013.