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 Penn Virginia Corporation (NYSE:PVA) jumped 15% today after activist investor George Soros became an active investor.

So what: In a filing, Soros said he increased his stake in the company from 8.2% to 9.2% and wants the company to explore strategic alternatives. But he also said the company is well-managed and wants management incentives to be increased.  

Now what: Soros isn't a new investor in Penn Virginia, and the increased stake indicates that he thinks management can make moves to unlock value if it wants to. I also thought it was interesting that he didn't seem to have any interest in shaking up management, specifically saying that they were doing a good job. Buying solely on Soros's stake isn't a good idea, but if you're looking for a reason to be more bullish on Penn Virginia, I think this is a good reason. Soros has a good history as an investor and may be able to stir up asset sales or acquisitions that could drive more value.

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Travis Hoium has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.