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: Dean Foods (NYSE: DF) is up 10% today on news that hedge fund manager David Tepper has built a large position in the company.

So what: Tepper made a fortune buying financial stocks at the bottom and is making another contrarian bet on Dean Foods, buying a 7.35% stake in the company. The stock has suffered a terrible fall since hitting highs in March 2007, but Tepper thinks the worst days are behind it.

Now what: Tepper is known for investing in volatile stocks, so buying into Dean Foods just because a big-name hedge fund manager is doing it isn't advised. However, I do like the contrarian pick and the low price-to-earnings ratio of 11 that Dean Foods has right now. I have to agree with Tepper on this one. I think Dean has hit rock bottom and is poised to continue its recent trend upward.

Interested in more info on Dean Foods? 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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