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 ATP Oil & Gas (Nasdaq: ATPG) fell 10% at the market open after the company released earnings.

So what: In the fourth quarter, revenues increased 90.7%, to $141.7 million, but the loss per share ballooned to $4.06 per share. Excluding one-time items, the loss would have been $14.6 million. Production increased to 24.9 million barrels of oil equivalent from 21.1 million in the third quarter.

Now what: Production is increasing, but the massive loss per share is a little concerning, even though most of the items were non-recurring. The stock has recovered some of the losses after early selling, and with analysts expecting ATP to swing into a profit next year, there should be positive news ahead. I'm cautious on today's move and will wait to see tangible financial results before jumping in.

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