Explain This: Yelp Stock Soars 21 Percent In Spite of Lock Expiry

We could not. You can try - we spotted this today:

"Shares of Yelp (YELP) were up 21% in midday trading Wednesday as 52.7 million shares were released from post-IPO lockups.

Lockup expirations usually pressure a stock, but in this case it's resulted in a short squeeze, says First Analysis Securities analyst Todd Van Fleet.

"The stock was declining in the face of the lockup expiration and there was a lot of short activity," Fleet said. "Then what we're seeing today probably is a lot of short covering."

That is, with the stock rising, short-sellers — who are betting that a stock falls — are selling fast in order to limit their losses. Yelp has had a higher-than-usual amount of short interest in its stock."

Statistics Source: Investors.com