NEW YORK (TheStreet) -- Valeant Pharmaceuticals  (VRX) stock gained 3.75% to $94.65 in Wednesday's trading session after activist investor Bill Ackman increased his stake to 9% from 8.5%.

Ackman purchased nearly 1 million additional shares of Valeant, according to a February 5 filing with the SECFortune reports.

He disclosed 21,591,122 shares of common stock and 9,120,000 shares of unexercised options, representing a 30% increase in common stock and a 27% decrease in options from the 2015 fourth quarter. 

Additionally, hedge fund investor Leon Cooperman sold his entire stake in Valeant, while Brahman Capital bought another 3.7 million shares and Paulson and Co. purchased an additional 4.4 million shares, Fortune notes.

Valeant is a specialty pharmaceutical and medical device company based in Canada.

Separately, TheStreet Ratings team rates the stock as a "hold" wit a ratings score of C.

Valeant's strengths such as its robust revenue growth, good cash flow from operations and expanding profit margins are countered by weaknesses including a generally disappointing performance in the stock itself, unimpressive growth in net income and generally higher debt management risk.

You can view the full analysis from the report here: VRX

TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this article's author. 

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