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 industrial machinery manufacturer Gardner Denver (NYSE: GDI) saw its shares fall as much as 13.7% today after the CEO resigned.

So what: CEO Barry Pennypacker quit the company unexpectedly and the vacancy at the top of the company has investors concerned about its future. Pennypacker was credited for helping improve the company's margins and growth in recent years.

Now what: Pennypacker's aggressive style appears to have rubbed people the wrong way and may have contributed to his exit. The company has had high turnover at the top and the board may have had enough. This leaves some question marks for the company, but with shares trading at just nine times trailing earnings I think the stock can recover from this fall.

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