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: PDL BioPharma (Nasdaq: PDLI) shares fell 11% today after the company lost a patent infringement case.

So what: A U.S. district court found Medimmune, a unit of AstraZeneca (NYSE: AZN), did not violate license agreements on royalties or infringe on PDL's patents. We are still waiting on a jury's decision on other claims, but this was a big blow to PDL.

Now what: In a worst-case scenario, PDL could have to repay up to $280 million in royalties paid from 1998 to 2009. The ruling today and potential future risks are enough to make me leave shares of PDL BioPharma alone for now. Despite its low 6.9 price/earnings ratio, there is a lot of overhanging risk that still needs to be resolved, although when they are resolved shares could look like a real value.

Interested in more info on PDL BioPharma? Add it to your watchlist.

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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