Ackman to CNBC: I haven't covered Herbalife short

Herbalife headquarters
Patrick Fallon | Bloomberg | Getty Images

In hedge fund manager William Ackman's first comments since January on his $1 billion bet against nutritional supplement company Herbalife, he told CNBC, "I haven't covered a single share."

Ackman wouldn't comment beyond that Tuesday evening, but he put out a press release earlier in the day laying out his concerns about the better-than-expected earnings that Herbalife released on Monday.

(Read more: Herbalife beats estimates, raises full-year outlook)

GAAP operating income at Herbalife grew by 3 percent, Ackman wrote, while revenue increased 18 percent. "Why is the company's operating earnings growth so weak?" he asked in the release. "Is the company 'buying' revenue growth at the expense of operating income?"

On Monday, Herbalife also raised its full-year guidance. The stock has increased about 60 percent since Ackman's Dec. 20, 2012, presentation in which he called the company a pyramid scheme—an accusation Herbalife has vehemently denied.

(Read more: Ackman questions Herbalife's income growth)

While the Wall Street's knee-jerk reaction to Herbalife's earnings this week was to run up the stock by more than 5.5 percent, it ended down by about 50 cents Tuesday.

Ackman has also told CNBC that he's acquired a 9.8 percent position worth $2.2 billion in industrial gas company Air Products & Chemicals. The 13D filing is expected Wednesday.

(Read More: Activist investor Ackman makes his biggest bet ever)

Earlier this year, the Pershing Square Capital Management boss slugged it out over Herbalife on live television on CNBC with rival billionaire investor Carl Icahn.

Icahn disagreed with Ackman's views, and he's since increased his stake in the company.

During the CNBC-Institutional Investor Delivering Alpha Conference earlier this month, Icahn joked, "I like Bill Ackman now. Anyone who makes me a quarter billion dollars, I like."

(Read More: Icahn rips into Dell board...and slams Ackman, too)

—By CNBC hedge fund specialist Maneet Ahuja and "Squawk Box" host Becky Quick.