Buzz Stocks: Horizon Pharma PLC, Potash Corporation of Saskatchewan, and Perrigo Company plc

With speeches from Fed officials in focus today, U.S. stocks appear set to continue Friday's sell-off. Among specific equities in focus are biotech stock Horizon Pharma PLC (NASDAQ:HZNP), fertilizer producer Potash Corporation of Saskatchewan (USA) (NYSE:POT), and drugmaker Perrigo Company plc Ordinary Shares (NYSE:PRGO).

• HZNP is set to slide 1% at the open, on news the company will purchase sector peer Raptor Pharmaceutical Corp. (NASDAQ:RPTP) in an $800 million cash deal. HZNP was off more than 20% year-to-date as of Friday's close at $17.26, and a continued slide could easily translate into negative analyst attention for Horizon Pharma PLC. At the moment, six out of seven brokerage firms rate the shares a "strong buy," without a single "sell" opinion on the books. Plus, the average 12-month price target of $30.36 sits at a 75.9% premium to HZNP's current trading levels, and a price point the shares haven't seen in nearly a year.

• POT is 2.8% higher in electronic trading, after the company announced it will merge with agricultural firm Agrium Inc. (USA) (NYSE:AGU), creating one of the world's largest companies in its sector, with a combined value of rough $36 billion. Buzz around a possible merger between the firms sent Potash Corporation of Saskatchewan (USA) soaring in late August, and options traders have continued to pick up the stock's call at an accelerated rate. At the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), POT's 50-day call/put volume ratio of 5.57 sits higher than 93% of all readings taken in the past year. The stock has been stuck in a sideways pattern since the end of January, but as of Friday's finish at $16.97, seems to have found a foothold above its 200-day moving average.

• PRGO is up 3.7% ahead of the bell, after activist investor fund Starboard Value LP disclosed a 4.6% stake in the drugmaker. In a letter to Perrigo Company plc's CEO John Hendrickson and the company's board, Starboard criticized PRGO's recent performance, and urged the company to consider selling non-core assets or other strategic alternatives. "Unfortunately, since [rejecting a bid from Mylan NV (NASDAQ:MYL)], results have gone decidedly in the wrong direction, and management's promises have been woefully unfulfilled," the letter said. As of Friday's close at $88.71 -- not far off a roughly five-year low, seen in mid-August --the shares were down 51% year-over-year. Plus, PRGO's 80-day moving average has been pressuring the stock lower for more than 12 months. Unsurprisingly, more than 80% of the analysts following PRGO rate the shares a "hold" or "sell."

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