Why SINA Corporation Stock Plunged Today

Adjusted quarterly revenue rose 23% year over year, to $310.8 million, including a 20.8% increase in online advertising revenue, to $269.6 million. Within the latter figure, advertising and marketing revenue from Weibo jumped 45%, to $187.9 million, more than offsetting a 23% decline in portal ad revenue, to $31.3 million. On the bottom line, adjusted net income nearly doubled, to $48.2 million, while adjusted net income per share rose 80% year over year, to $0.63.

By comparison, analysts' consensus estimates predicted SINA would turn in lower adjusted revenue of $301.6 million, and adjusted earnings of only $0.55 per share.

IMAGE SOURCE: SINA Corp.

Now what

Assuming exchange rates remain steady, SINA anticipates adjusted revenue for the full year of 2017 to be between $1.30 billion and $1.44 billion, which was also significantly above the $1.27 billion investors were expecting.

So why the decline? For one, keep in mind that even after today's drop, shares of SINA are still up more than 60% over the past year. So perhaps some investors are taking profits off the table in spite of SINA's relative outperformance this quarter.

And to be fair, SINA still has work to do in continuing to better monetize the growing mobile user base of its weaker portal business. But even then, management insisted during the subsequent conference call that its portal advertising business has "very much stabilized," and should continue to improve as we get deeper into 2017.

In short, sometimes our fickle market's reaction to earnings simply doesn't line up with what's actually happening in the business. In SINA's case, I think this could ultimately prove to be a compelling opportunity for patient investors to open or add to their positions.

10 stocks we like better than SinaWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.*

David and Tom just revealed what they believe are the 10 best stocks for investors to buy right now... and Sina wasn't one of them! That's right -- they think these 10 stocks are even better buys.

Click here to learn about these picks!

*Stock Advisor returns as of February 6, 2017

Steve Symington has no position in any stocks mentioned. The Motley Fool recommends Sina. The Motley Fool has a disclosure policy.