Ackman said again in the letter that he is sticking with Valeant - which surged 16.41 percent on Tuesday - saying, "We do not believe that Valeant's long-term earnings prospects have materially changed."
As of early November, Valeant's stock price had plunged 70 percent from its peak in August. But the stock has since recovered some ground as Ackman and other large investors bought more shares. In the last weeks Ackman used over-the-counter options transactions. He said in the letter that if the stock price rises to $165 or more by January 2017, "We will make more than 10 times our net investment over this period."
Ackman said uncertainty surrounding Valeant - including its drug pricing and accounting practices - should begin to disappear on Wednesday when the company discloses what it will likely earn next year.