When combing through Barron's over the weekend I always make it a point to check out the "Short Interest" tables when they appear. I'm curious, in particular, about the ups and downs in Dendreon (DNDN). Right now it's 39th on Barron's list of the Top-40 largest short positions.

To take a small step back, the short interest is a barometer of bearish investors in a stock. These are people (oftentimes hedge funds) who think shares are gonna go down and position themselves to make money if/when they do.

Anyway, this weekend one name on the list jumped out at me: Amgen (AMGN). According to Barron's, the number of Amgen shares being shorted skyrocketed 114 percent from May 30th to June 13th. It more than doubled in two weeks! On May 30th nearly 23 million Amgen shares were being shorted and by June 13th more than 48 million shares were in the claws of the bears. That puts Amgen in 14th place among the Top-40 largest short positions, but it is number two on the list of largest changes in short positions behind Sun Microsystems (SUNW).

What's behind the pessimism? It could be that any day now the Food and Drug Administration could issue new restrictions on the use of Amgen's anemia drugs in cancer patients. An FDA Advisory Committee made recommendations to the agency about that last March. So, maybe a growing number of investors have a hunch the FDA could be more stringent than its panel of outside experts. And then, of course, there's the data expected later this year on Amgen's all-important osteoporosis drug D-mab. Or possibly something else I'm not aware of might be stoking the shorting.

Amgen reports its second quarter earnings July 28th after the closing bell.

Amgen, by the way, is one of the many biotech stocks FBR is suspending coverage of today "due to the departure of the analyst." That would be Jim Reddoch. I don't know the backstory yet.

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Mike Huckman

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