(Read more: SAC retrenches as insider trading probe drains firm)
Another addition to Conatus is James MacKendree as head of business development and investor relations. He was most recently co-head of business development for North America at $27.7 billion GLG Partners.
MacKendree will try to add to Conatus' already rising assets under management. The firm, founded in 2007, ran $2.25 billion on Dec. 31, 2012 but now manages $2.74 billion.
Conatus also recently hired Chris Philips as a senior financials analyst from $14.2 billion Thomas H. Lee, where he was an associate, and Samia Bahu as a research assistant from $1.7 billion private equity firm Newbury Partners.
Scott Tagliarino, a spokesperson for Conatus with public relations firm ASC Advisors, declined to comment.
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Performance has been strong. Conatus Capital Partners rose 3.2 percent net of fees in the third quarter, bringing the fund to a 12.7 percent gain for the year through September. That's better than the Absolute Return U.S. Equity Index benchmark of 8.97 percent over the same period.
Recent winning stocks include Gulfport Energy, Pioneer Natural Resources, Facebook, LinkedIn and Amazon.com, according to the Oct. 16 letter. Asia stocks Tencent, Ctrip.com, Alibaba and European equities EADS and Volkswagen also performed well.
New positions over the third quarter include Adobe Systems, B/E Aerospace, McGraw Hill Financial, McKesson, Moody's, Softbank, Starbucks and Twenty-First Century Fox.
On Japanese telecommunications and internet company Softbank, Stemerman wrote that "our sum of the parts analysis yields a valuation materially higher than where shares currently trade."
(Read more: Japan's SoftBank to pay $1bn for Brightstar stake)
On Chinese travel company Ctrip, Stemerman said the company's expansion into mobile and web services positions it well for the growing Chinese market.
Stemerman, a veteran of Stephen Mandel's Lone Pine Capital, also noted a new short position in an undisclosed Canadian grocery company.
"One company has among the highest operating margins of any grocer in the world despite having the limited scale of a regional producer," he wrote, noting increased competition from Wal-Mart, Target and Loblaw.
"We believe that this company's industry leading margins are a consequence of prices that are higher than the competition. This high price position makes the company highly vulnerable as lower-priced competitors gain traction."
Besides Loblaw, top Canadian retail chains include Metro and Empire, which owns Sobeys.
(Read more: Grocer Loblaw to eliminate about 275 jobs)