It’s not just Facebook investors who are feeling antisocial

That giant sound you’re hearing is the air seeping out of the social-media bubble.

On top of Friday’s broad market declines, here’s the latest afflicting a crop of companies in the sector on Monday:

A Bernstein Research analyst slaps a sell on Facebook Inc. (



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) and raises questions about the social network’s revenue and growth opportunities. Its stock is almost 30% below its IPO price of $38 on May 18. Read more in Ratings Game.

Groupon Inc.’s (



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) market capitalization falls below $6 billion, the price Google Inc. (



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) was set to pay for the daily-deals site in 2010. The lockup period for company insiders to sell stock expired on Friday. Shares of Groupon are trading below $9 after going public in November at $20.

Yelp Inc. (



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) stock slips below its debut price of $15, losing 45% of its value in the last three months.

Whether you blame Facebook’s controversial IPO for spoiling the party or not, it’s clear investors are feeling antisocial.

-Anthony Lazarus

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