San Francisco, UNITED STATES
Philanthropist Bill Gates embraces Facebook's Mark Zuckerberg during an announcement of the Chan Zuckerberg...
Philanthropist Bill Gates (L) embraces Facebook's Mark Zuckerberg during an announcement of the Chan Zuckerberg Initiative to "cure, prevent or manage all disease" by the end of the century during a news conference at UCSF Mission Bay in San Francisco, California, U.S. September 21, 2016. REUTERS/Beck Diefenbach