When trading resumed, shares fell more than than 12%.
According to the Bloomberg report, based on interviews with people familiar with the matter, Yelp had been approached by several companies but is no longer interested in selling any time soon.
Yelp hired Goldman Sachs after receiving interest from a potential buyer, according to Bloomberg.
The company is currently valued at nearly $3 billion.
Its stock price spiked more than 25% on May 7 after initial reports that it was exploring a sale, but is now back near the level it was before that news.
Following the news, analysts at Credit Suisse (noting they couldn't confirm the report at the time) identified six potential buyers, including Google, Apple, Amazon, and TripAdvisor.
Here's a chart showing the plunge in shares on Thursday:
Google Finance