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 drugmaker Theravance (Nasdaq: THRX) jumped 10% today after partner GlaxoSmithKline (NYSE: GSK) announced an additional investment in the company.

So what: GlaxoSmithKline will buy 5.75 million shares for $22.50 each for an additional investment of $129.4 million in Theravance. This will bring GlaxoSmithKline's stake up to 19% as the company gains confidence in new lung disease and asthma drug Relovair.

Now what: It looks like GlaxoSmithKline got a pretty good deal on the shares considering the stock closed at $22.85 last week and shares are now trading around $25.20. This isn't quite a takeover bid, but I have to wonder if there will be one coming in the near future. Despite continued losses at Theravance, I think if the stock pulls back over the next few days it could be a good deal. I just don't want to pay too much more than the deal GlaxoSmithKline is getting.

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Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

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