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 Questcor Pharmaceuticals (Nasdaq: QCOR) fell 13% today after reporting better-than-expected earnings. Wait, what?

So what: It's all about the details of the earnings report. Revenue rose 144.6% from a year ago to $112.5 million, topping estimates, and adjusted earnings per share were $0.69, six cents above estimates.

But the problem today is the number of rebated prescriptions of Acthar, the company's $23,000-per-vial drug. One estimate from ThinkEquity estimated that 94 MS prescriptions were rebated for a total of 1,167 including paid, but the actual number was 41 for a total of 1,151 total prescriptions. The trend for nephritic syndrome was similarly disappointing.

Now what: I wouldn't be too worried about the rebate miss, the company has been increasing paid prescriptions at a rapid rate, and both the top and bottom lines were better than expected. Shares now trade at 10 times forward earnings, and if current trends continue, that could be a great deal for investors. Investors can often freak out about small details in earnings reports, but I think the overall picture looks strong, and shares cam move higher from here.

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