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 oil and gas explorer Venoco (NYSE: VQ) sank as much as 16% in early trading after announcing that it may sell up $75 million of stock through an "at-the-market" share offering program and cutting its 2010 average production forecast.

So what: Naturally, management's plan to sell a big chunk of stock directly into the market for "general corporate purposes" should do well to pressure the shares in the short term. Couple that with continued depressed natural gas prices, which prompted the production cut, and it's to see why Venoco shareholders aren't exactly pleased today.

Now what: While it's usually good to be greedy when others are fearful, now isn't the time to do it. Shares of Venoco have been on fire in 2010, making the stock sale announcement all the more worrisome. With solid big oil stocks like ExxonMobil (NYSE: XOM) and Chevron (NYSE: CVX) available at verifiably cheap prices, taking a chance on Venoco doesn't seem worth it.

Interested in more info on Venoco? Add it to your watchlist 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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