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Steve Schwarzman, chairman, CEO and co-founder, Blackstone Group: European real estate. "[It's] still is a very interesting idea."
Leon Black, chairman and CEO, Apollo Global Management (he gave two): Energy-related investments and European financial institutions.
Jim Coulter, CEO and founding partner, TPG: Health care. "There's a huge disruption going on and it's not attached to the rest of the economy."
Robert Smith, founder, chairman and CEO, Vista Equity Partners: 3-D Printing. "That whole technology, that sphere of influence, will actually change a number of industries ... and will be a massive disruption."
Jonathan Nelson, founder and CEO, Providence Equity Partners: Premium content and digital distribution.