I kind of wish I'd given my wife this deal when we got engaged: If you can find a more suitable mate, you have to let me at least match the offer, and if I don't, you have to pay me $50 million. Fortunately she said, "I do," even without the offer. On the other hand, that's the deal that Beckman-Coulter (NYSE:BEC) got when it agreed to acquire Biosite (NASDAQ:BSTE) in March for $85 per share, a whopping 54% premium on the previous day's closing price.

Biosite runs a high-margin business selling clinical diagnostic tests, which should complement Beckman-Coulter's laboratory instrument business. But there was concern that, at 40 times earnings, Beckman-Coulter may have overpaid for the business. That makes Inverness Medical Innovations' (AMEX:IMA) unsolicited bid of $90 per share last month a little surprising. Inverness sells clinical diagnostic products, much like Biosite, so perhaps it figured that merging would help reduce costs, further increasing the margins on both companies' products.

Since $90 is obviously more than $85, Biosite's board decided this was a "superior proposal" and told Beckman-Coulter to cough up more dough or say goodbye to their merger. Yesterday, on its final day to decide, Beckman-Coulter agreed to up its offer for Biosite to $90 per share. Beckman-Coulter's share price fell 1.8% yesterday, but it also reported positive first-quarter results, so it's hard to tell just how unhappy investors were about the increased acquisition expenses.

Biosite investors certainly think that Inverness -- or dare I say, a third bidder -- will come back with a higher offer; Biosite closed at $93.75 per share yesterday. While Inverness may make a higher bid for Biosite, I'm going to watch from the sidelines. I prefer to invest in companies based on strong science, not by making educated guesses about when bidding wars will end.

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Fool contributor Brian Orelli, Ph.D. has been married to his wife for seven years and likes to think she's worth $50 million. He doesn't own share of any companies mentioned in this article. He blogs about start-up biotech companies at Babybiotechs.com. The Fool has an iron clad disclosure policy.