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 independent oil refiner CVR Energy (NYSE: CVI) sank 10% in early Wednesday trading after announcing that some of its investors, including Goldman Sachs (NYSE: GS) and Kelso & Co., will sell 15 million shares in a secondary offering.

So what: CVR shares were up about 60% for the year prior to today's plunge, so Mr. Market seems to have good reason to raise an eyebrow over today's announcement. CEO John Lipinski also said that he'd be selling 70,000 for personal tax purposes, further fueling bearish suspicions that the stock may be overvalued.

Now what: I'd keep my distance from CVR at this time. While it's entirely possible that the stock can keep rocketing, today's news, coupled with a P/E of 40, lead me to believe that there are probably better values in the space. Rival refiners like Tesoro (NYSE: TSO), Western Refining (NYSE: WNR), and Valero (NYSE: VLO), all of which haven't been nearly as hot as CVR, might be good places to start.

Interested in more info on CVR? Add it to your watchlist here by clicking here.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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