Giving Pledge Adds Ultra-Rich Members to Donate Their Wealth (1)

The Giving Pledge has brought on 11 new signatories in its latest effort to spur philanthropy of the ultra-wealthy.

Drew Houston

Photographer: Martina Albertazzi/Bloomberg

Billionaire Dropbox Inc. co-founder Drew Houston and Invisibly founder Jim McKelvey, along with their spouses, are among the group that has penned letters promising to give away the majority of their wealth in their lifetime or their will.

They join more than 240 others who have signed since Warren Buffett, Melinda French Gates and Bill Gates founded the Giving Pledge in 2010. Some of the wealthiest pledgers include Elon Musk, Mark Zuckerberg, Bill Ackman and Steve ...