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What: Shares of Jabil Circuit (NYSE: JBL) short-circuited today, down by as much as 10%, after the company reported earnings yesterday.

So what: Revenue was $4.3 billion, roughly flat with the year-ago quarter, and adjusted earnings per share was $0.54. Those results were slightly worse than the market was expecting on revenue, but the bottom line fell short by about $0.04 per share. Jabil Circuit also guided next quarter below consensus estimates.

Now what: The coming quarter should see sales in the range of $4.3 billion to $4.5 billion, with earnings per share between $0.51 and $0.62. Analysts were calling for $4.52 billion in revenue and a $0.67 per share profit. Jabil Circuit is running into shrinking margins related to providing the aluminum casing in Apple's (Nasdaq: AAPL) iPhone 5, since Apple is one of its biggest customers. The new smartphone is ramping up production to meet demand, causing negative pressure on Jabil Circuit's results.

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Fool contributor Evan Niu owns shares of Apple, but he holds no other position in any company mentioned. Click here to see his holdings and a short bio. The Motley Fool owns shares of Apple. Motley Fool newsletter services have recommended buying shares of Apple. Motley Fool newsletter services have recommended creating a bull call spread position in Apple. The Motley Fool has a disclosure policy.

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