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Four of the most important new names in activism took master classes with the strategy's deans, Ackman and Icahn.
Icahn's top protégés are Keith Meister, who runs $8 billion Corvex Management, and Alex Denner, who runs $639 million Sarissa Capital Management.
Meister, 41, rose to be chief investment officer at Icahn Capital before he launched Corvex in late 2010. Meister's firm has grown quickly and now manages more money than any of his rising star peers, thanks to backing from Soros Fund Management, Blackstone Group and others.
Recent targets include American Realty Capital Properties, energy group Williams Companies and Fidelity National Financial. All three company stocks are up this year.
A smaller activist with Icahn heritage is Denner, 45, who focuses on healthcare at Sarissa. Denner, 45, has a background in biomedical engineering from a doctorate at Yale University. He worked at Icahn Capital from 2006 to 2011 following a brief stint as a healthcare portfolio manager at prominent hedge fund firm Viking Global Investors in 2005 and 2006.
Greenwich-Connecticut-based Sarissa was founded in 2013 and had grown to manage $639 million at the end of February. Denner has favored a small group of larger bets on healthcare-related companies; recent targets include Ariad Pharmaceuticals, Vivus and Astex
Performance has been positive but subdued: Sarissa's main fund gained 7.9 percent from May to December 2013, 9.6 percent in 2014, and 2.5 percent in 2015 through February, according to a person familiar with the situation.
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Two more up-and-coming activists got their start at Pershing Square.
One is Ferguson, the first investment staffer hired by Bill Ackman when starting the now well-known hedge fund shop in 2003. The Harvard MBA rose to become a partner before leaving to found Sachem Head Capital Management in 2012.
Ferguson, 40, now runs about $3 billion. A prominent recent target was animal health company Zoetis, an investment that Ackman joined in November with an even larger stake. Pershing Square won a board seat in February with the promise of another appointment soon. The stock is up about 25 percent over the last 6 months.
Pushed up by Zoetis and another player, CDK Global, Sachem Head gained about 20.5 percent net of fees last year, according to a person familiar with the situation
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Another Ackman protégé is McGuire. The former Pershing Square partner founded Marcato Capital Management in 2010. Based in San Francisco, 38-year-old McGuire has grown his shop to manage $3 billion. Marcato has taken on big companies recently, including Bank of New York Mellon, Sotheby's, and Lear.
Marcato has generated double-digit returns every year since its inception except for 2014, when it returned 5.3 percent. The fund up about 2.4 percent this year after a big gain in February.
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