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What: Shares of SINA (Nasdaq: SINA) are soaring today by as much as 14% after the company reported fourth-quarter earnings yesterday.

So what: The figures were mostly in line with Street expectations, with revenue of $128.7 million and a $0.21 per-share profit. Next quarter's guidance actually came in a tad light, with sales expected between $101 million and $104 million compared to the nearly $114 million consensus estimate.

Now what: It was a mixed bag of news, but one of the bright spots was that the company said its Twitter-esque Weibo service should start bringing in revenue by the tail end of the year. CEO Charles Chao expects "meaningful monetization" from the service driven by display advertising and various fee-based services. On the flip side, the company warned that government-imposed requirements for identity verification could put a drag on user activity. Don't forget to check out fellow Fool Rick Munarriz's breakdown of the release.

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