I'd be stunned if a partnership yielded $15-20 million upfront. In a meeting last year, a BP BusDev VP said that he would never go in with a proposal to spend more on an upfront payment than the company's market cap, because his BOD would say--why don't we just buy it?
You're not comparing apples and apples. A partnership upfront cannot be directly compared to a buyout bacause this assumes that a BP could buy up sufficient shares at current market cap. An unlikely scenario at best. They would have to offer at least a 50% or greater premium to current prices to achieve a controlling position. With a current market cap of $13.5 million, I would expect an offer of at least $20 million for a serious buyout proposal. As you observed, once the offer becomes public the share price...and resulting market cap...will immediately rise to approximate the offer values.
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