"Herbalife continues to face an unprecedented and unrelenting attack from Pershing Square to support its $1 billion bet to manipulate and drive Herbalife's stock price to zero to the detriment of our investors, members, customers and employees," the nutritional supplement company said in a press release Thursday.
"Herbalife is confident that the facts are on its side and that it will overcome Pershing Square's campaign of misinformation about the company as the truth about Pershing Square's increasingly desperate accusations is revealed."
The release coincided with this tweet targeting the hedge fund manager and including the hashtag "#WorstOfWallStreet," an apparent play on the movie title "The Wolf of Wall Street" (see the full tweet here).
Spokesmen for Herbalife and Pershing Square declined to comment, but the move appears to be in preparation for a new presentation by Pershing Square on Tuesday. The event will be an "in-depth analysis and examination" of Herbalife's Nutrition Clubs, which the hedge fund firm claims are "a core driver of Herbalife's pyramid scheme."
Herbalife defended its nutrition clubs in the same press release.
"Herbalife member-sponsored nutrition clubs play a positive role in promoting a community-based approach to health and wellness across the United States," the company said. "Nutrition clubs advance Herbalife's mission of helping people lead healthier lives. Our community-based approach to health and wellness is well recognized as an important tool in helping create and sustain changes in behavior."
Herbalife has been aggressive in defending itself since Ackman unveiled his now-famous $1 billion bet against the company in December 2012. But it took a particularly strong approach with its latest salvo.
For example, Herbalife rejected Pershing Square's claim that there was no real demand for its products given the alleged focus on making money from recruiting other distributors, not actually using or selling the nutritional shake formulas and other goods.
"A pillar of Pershing Square's thesis is its assertion that there is no genuine consumer demand," the company said. "Thus, Pershing Square's thesis is built upon the proposition that last year, roughly a half million people collectively decided to simply discard $881 million worth of Herbalife products rather than get the refund to which they were entitled. And, according to Pershing Square, this has happened every year for the past 34 years."
Herbalife stock is down about 23 percent in 2014.
—By CNBC's Lawrence Delevingne