Bill Ackman takes a break—for now

Bill Ackman joins Squawk Box on their first day at their new set in New York City.
Adam Jeffery | CNBC
Bill Ackman joins Squawk Box on their first day at their new set in New York City.

Bill Ackman appears set to take it relatively easy for a few months after a slew of activist investments produced knockout performance in 2014.

Ackman's hedge fund firm, Pershing Square Capital Management, has far less than 10 percent of its $18.2 billion in free cash—under the amount usually needed to mount a fresh campaign, according to a dinner presentation for investors Jan. 29. The specific amount is about $500 million, according to The New York Post.

Pershing Square historically keeps 13.6 percent of its assets in cash, which can be used to fund new investments or give money to clients who want out, according to the presentation.

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Wall Street also isn't likely to see a big public short campaign again from Ackman soon.

"You'll never hear about it," he told CNBC in January. "I may be done with public shorts. This may be—Herbalife—one of the last."

Pershing Square's main fund gained 40 percent in 2014 net of fees, among the best performances in the hedge fund industry.

Big winners were Allergan (a long bet up 19 percent), Canadian Pacific Railway (a long up 7 percent), Herbalife (a short up 6.1 percent) and Restaurant Brands International (a long up 5.5 percent), according to an annual firm review of performance drivers given at the recent dinner.

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Actavis' purchase of Allergan is expected to be completed this spring, which would free up billions of dollars for Pershing Square.

A spokesman for Pershing Square declined comment.