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% well after trading began today as oil and gas shares fell.

So what: This was really more of a move hitting oil and gas stocks more than it was anything specific to ATP Oil & Gas. Comstock Resources (NYSE: CRK), MGX Resources (NYSE: GMXR), and ATP all traded lower in similar patterns as the price of oil fell.

Now what: There’s a lot going on in the market affecting these companies, but falling oil prices were the biggest factor today. Oil is down 1.3% as I write this, because traders are fretting about the economy and the future demand for oil. As usual, these stocks are really leveraged bets on the price of oil; with oil down it’s no surprise they’re trading lower today.

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