Set for Sohn: Tepper, Ackman, Einhorn and more

David Tepper, your average “middle-class” billionaire.
Adam Jeffery | CNBC
David Tepper, your average “middle-class” billionaire.

The Sohn Investment Conference is back on this year for its 20th edition, and the money managers slated to speak are as big as ever.

The May 4 New York charity event, which raises money to cure and treat pediatric cancer, will include investment idea presentations from BillAckman of Pershing Square Capital Management, Leon Cooperman of Omega Advisors, David Einhorn of Greenlight Capital, Larry Robbins of Glenview Capital Management and David Tepper of Appaloosa Management, among others.

"Wall Street's best and brightest investors participate in this unique, 'must attend' event to share their expertise with an audience of more than 3,000 people, comprised of portfolio managers, asset allocators and private investors," event materials explain.

Other speakers this year are Mala Gaonkar, co-portfolio manager of Lone Pine Capital; Jeff Gundlach, CEO of DoubleLine Capital; Keith Meister, founder of Corvex Management; and Barry Rosenstein, founder of JANA Partners.

Some of the speakers this year are repeats from 2014. Ackman pitched Fannie Mae and Freddie Mac long positions at the May 5 event; that trade has so far backfired, with both stocks down by about one-third since the presentation was made.

Read MoreAckman: Fannie 'best trade...in capital markets'

Einhorn recommended shorting Athenahealth. The stock is down about 2 percent since the high-profile attack was made.

And Robbins recommended going long Humana, WellPoint and Monsanto. Humana is up nearly 60 percent; WellPoint (which changed its name in December to Anthem) is up more than 50 percent; and Monsanto is up nearly 4 percent.

Read MoreLarry Robbins ofGlenview: Monsanto should be piling on debt