Bloomberg News reported last week that Bristol-Myers Squibb (NYSE: BMY) had made an unsolicited offer to buy Amylin Pharmaceuticals (Nasdaq: AMLN) for $22 per share.

Cue Carl Icahn.

The billionaire's fund has a nearly 9% stake in Amylin, making it the third-largest shareholder. Not surprisingly, he's got something to say about the potential deal.

Here's another not-so shocker: Icahn wants the diabetes specialist sold. The short-term-thinking activist investor has never been one to turn down a quick sale. Threats of a proxy fight were enough to get MedImmune sold off to AstraZeneca. Genzyme was sold to Sanofi (NYSE: SNY) soon after Icahn's nominees joined the board. It took a little longer to get ImClone Systems sold, but after becoming chairman, Icahn got Eli Lilly (NYSE: LLY) to outbid Bristol-Myers Squibb for the biotech.

Not that he's always been successful finding new homes for the biotechs he invests in. Icahn has had multiple proxy fights with Biogen Idec (Nasdaq: BIIB), but the company remains independent.

In his letter to Amylin's board of directors, Icahn is also a little miffed that the company did a secondary offering last month at $15.62 per share and issued options to company executives at $16.02 per share. The options grant seems reasonable since it was part of the normal compensation package, unless you want to assume the company executives turned down the $22 offer because they were waiting for the next option granting cycle. The capital raise doesn't make any sense if the company was going to get sold; it just diluted current shareholders. But if the board didn't think $22 was enough and didn't think Bristol-Myers was going to top it, continuing with business as usual would be the prudent thing.

Of course, neither Amylin nor Bristol-Myers has confirmed the Bloomberg report, so this could all be for naught.

Icahn got two people elected to Amylin's board a few years ago, but to get the company sold, he'll need a few more seats on the board. Unfortunately for him, the nomination period for the upcoming board meeting has already passed. Icahn has asked the company to reopen the nomination period, but I wouldn't count on the board catering to the activist investor.

What's the next move? Investors have to wait and see if one side will confirm the bid. If they don't, it seems likely Amylin's share price will be headed back to the teens with or without Icahn's clamoring for a sale.

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