Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Herbalife Ltd. (NYSE:HLF) were looking healthier today, jumping as much as 26% after the market rejected Bill Ackman's short-selling presentation today. 

So what: Shares of the nutritional supplement seller dropped 12% yesterday after Ackman, the head of Pershing Square Capital Management and an Herbalife short-seller, promised to deliver a "death blow" to the company in a presentation exposing it as a "massive fraud" today. However, that didn't happen. In his argument, Ackman said the company's hiring practices violate U.S labor law, and he again called the multi-level marketer a "pyramid scheme," insisting that sellers make more money for recruiting new members than selling the actual product. Herbalife once again emphatically denied Ackman's claims in a press release following the presentation.

Now what: In its response, Herbalife noted that Ackman reaffirmed that "Herbalife is first and foremost a company with great products that people want," and that millions of customers choose its products. Continuing on, the company said Ackman again "over-promised and under-delivered in his presentation, and merely showed that the facts were on Herbalife's side. As the stock's jump shows, investors clearly agreed, rejecting Ackman's thesis. This saga is far from over as Ackman earlier this year convinced the DOJ to investigate Herbalife, but Herbalife has won this battle, and next time Ackman calls for Wall Street's attention, he likely won't have as much sway.

Jeremy Bowman has no position in any stocks mentioned. The Motley Fool has the following options: long January 2016 $57 calls on Herbalife. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.