Elsheshai described Facebook as opaque and said his own impressions as a user helped give him confidence to act against what was fairly bearish commentary at the time.
He said the negativity had appeared to be mainly anecdotal, such as stories of teenagers switching to other social media services, but that did not match his own experience or the data he saw.
"It seemed clear you were starting to see a broader set of advertisers" on the service, said Elsheshai, who is based in Minneapolis and has 462 Facebook "friends" at last count.
Another enthusiast for Facebook is Chris Carter, co-manager of the $549 million Buffalo Growth Fund, advised by Kornitzer Capital Management in Shawnee Mission, Kan.
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The Growth Fund had bought Facebook shares last year and added to the position this spring on Carter's suggestion. It now holds around 370,600 Facebook shares, up from about 300,000 at the end of February, according to Carter.
Carter, 34, said he was encouraged by Facebook's strength in advertising on mobile devices, where the ads stand out compared to those that appear on desktop machines.
Seeing ads on the Facebook app on his own iPhone 5 helped inform his decision, said Carter, who has about 175 Facebook friends. "If I hadn't seen that, I would be wondering what's up," he said.
Not every investor relied on his own experience with Facebook. Jay Welles, a senior equity analyst at Manning & Napier in Fairport, N.Y., said he followed Internet tracking firms such as comScore, which continued to report growing traffic to Facebook.
Welles recommended his firm buy Facebook shares in the spring, and said it has not sold them since.
"We felt the user base was very sticky. Facebook had a lot of hooks into the users," said Welles, 35. He uses LinkedIn, but not Facebook. "My own personal experience isn't the relevant factor," he said.
The $1.2 billion Manning & Napier Equity Series fund held 442,520 shares of