A123 Systems (Nasdaq: AONE) reported earnings yesterday. Here are the numbers you need to know.

The 10-second takeaway
For the quarter ended Dec. 31 (Q4), A123 Systems whiffed on revenues and missed expectations on earnings per share.

Compared to the prior-year quarter, revenue improved significantly, and GAAP loss per share grew.

Gross margins contracted, operating margins expanded, and net margins dropped.

Revenue details
A123 Systems tallied revenue of $40.4 million. The nine analysts polled by S&P Capital IQ hoped for sales of $54.5 million on the same basis. GAAP reported sales were 68% higher than the prior-year quarter's $24 million.

Source: S&P Capital IQ. Quarterly periods. Dollar amounts in millions. Non-GAAP figures may vary to maintain comparability with estimates.

EPS details
Non-GAAP EPS came in at -$0.56. The eight earnings estimates compiled by S&P Capital IQ averaged -$0.49 per share on the same basis. GAAP EPS were -$0.65 for Q4 against -$0.43 per share for the prior-year quarter.

Source: S&P Capital IQ. Quarterly periods. Non-GAAP figures may vary to maintain comparability with estimates.

Margin details
For the quarter, gross margin was -92.8%, 5,540 basis points worse than the prior-year quarter. Operating margin was -175.6%, 310 basis points better than the prior-year quarter. Net margin was -210.5%, 2,040 basis points worse than the prior-year quarter.

Looking ahead
Next quarter's average estimate for revenue is $20.8 million. On the bottom line, the average EPS estimate is -$0.36.

Next year's average estimate for revenue is $238.2 million. The average EPS estimate is -$1.35.

Investor sentiment
The stock has a two-star rating (out of five) at Motley Fool CAPS, with 422 members rating the stock outperform and 64 members rating it underperform. Among 92 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 74 give A123 Systems a green thumbs-up, and 18 give it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on A123 Systems is hold, with an average price target of $5.56.

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