Ackman on Herbalife: 'I'd go find another job'

My most important contribution: Ackman on Herbalife

Hedge fund manager Bill Ackman on Monday took more swipes at Herbalife, saying he has not changed his highly-publicized bet against the nutritional company.

"If you find yourself as an Herbalife employee today, my advice is that you should leave the company because this is not going to be a good thing on your resume. I'd go find another job," the Pershing Square Capital Management CEO said on CNBC's "Fast Money: Halftime Report."

Ackman took his short position in Herbalife more than three years ago, and he said Monday his bet against the company is roughly $1 billion. He has publicly crusaded against Herbalife, repeatedly calling it a pyramid scheme and saying its business model harms people.

His actions have not prevented Herbalife shares from climbing. The stock has risen more than 40 percent in the last year.

Bill Ackman
Adam Jeffery | CNBC

Herbalife said in a response to the hedge fund manager's overall criticism that its business has "not only survived, but has thrived" amid Ackman's attacks.

"After spending hundreds of millions of dollars and having a negative return on his investment, maybe it is just time for Bill to move on," the company said.

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Ackman, though, believes the company faces more difficulties ahead. He contended Herbalife's business "has deteriorated dramatically."

In February, Herbalife said adjusted earnings for 2015's fourth quarter came in at $1.19 per share, compared with $1.41 per share in the year-earlier period. It also said it expects adjusted 2016 EPS of $4.05 to $4.50 per diluted share from a previous range of $4.35 to $4.75 per share due to foreign exchange rates.

Ackman argued that the company, which relies on distributors, harms undocumented immigrants trying to make a living in the United States.

A documentary called "Betting on Zero," which chronicles Ackman's campaign against Herbalife, debuted earlier this year.