Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of biotechnology company Human Genome Sciences (Nasdaq: HGSI) popped 13% on Tuesday on speculation that it will be acquired by lupus drug partner GlaxoSmithKline (NYSE: GSK).

So what: According to British newspaper The Daily Mail, Glaxo could be poised to make a $25-per-share bid for Human Genome, representing a whopping 123% premium over its Monday closing price. Of course, The Daily Mail didn't exactly cite any sources close to the matter and both companies declined to comment, so investors shouldn't read too much into the takeover rumor.

Now what: The Daily Mail added that Merck (NYSE: MRK) and Biogen Idec (Nasdaq: BIIB) could also be looking into scooping up the company, so I wouldn't expect the buyout buzz to wear off anytime soon. After all, Human Genome shares have been beaten pretty hard recently (down 45% over the past three months), so it's not unreasonable to think that one of the drug behemoths could be smelling an opportunity. Of course, given Human Genome's less-than-stellar fundamentals, only speculative-types should consider getting involved.

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