>If a company wants to make some sort of a low-priced takeover offer, it would make sense for them to first work the price lower and then make an offer which is well above the current trading point.<
Can you name even one documented case where something like this happened to a biotech company? I emphasize the word documented because you have a tendency to see enemy action in what others regard as routine.
The GTCB pill or "shareholder rights" plan looks like a standard plan that allows the shareholders to purchase stock at 50% of market if someone acquires a significant block (I believe 15% under this plan) without the board's approval. The plan was adopted back in 2001 and the legal documents can be reviewed at http://sec.gov/Archives/edgar/data/904973/000091205701518400/0000912057-01-518400-index.htm
You are correct, though, that it is very hard to defend against an all cash offer substantially higher than the current price. If sufficient shareholders tender, the dilution caused by the pill might be manageable, although I'm not sure if there has ever been a case where a pill was actually triggered.
Whether someone would be willing to try a hostile bid depends in part on whether you think the value is intellectual property or people. If management and the staff are not willing to approve and will walk, will the buyer want the company? The example you gave in response to Dew on this question was not biotech.
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