Yelp was at $24.18, up $9.18 or 61 percent in midmorning. Late Thursday, the company priced the shares at $15, $1 ahead of the prior goal, as the company raised $107 million in its initial public offering.
The pricing valued the company at $898 million but as a result of the initial activity boosts it to about $1.4 billion. The overall market rose slightly Friday morning after setting several records this week.
The company sold 7.15 million shares in an offering managed by Goldman Sach, Citigroup and Jefferies, along with Oppenheimer and Allen & Co.
Yelp's rival, New York-based Zagat, sold itself last September to Google, the No. 1 search engine, for about $225 million in a deal shopped by co-founders Tom and Nina Zagat. They were also the sole co-owners.
Jeremy Stoppelman, 34, Yelp's CEO, has been preparing the seven-year-old site to be public, having rejected bids from both Yahoo and Google that valued the company at $1 billion. He was VP for engineering at PayPal before its acquisition by eBay.
Yelp was financed by venture capital, with funds from Elevation Partners, whose investors include Irish rock star Bono; Bessemer Ventures and Benchmark Capital. The trio own nearly 60 percent of the company.
Yelp has yet to turn a profit since its founding in 2004, so investors in its IPO will have to be patient. The prospectus says Yelp's net loss in 2011 was $16.9 million on revenue of $83.3 million.
The IPO is among the first of 2012 for an Internet-based commerce site and could serve as a lead-in to the Facebook IPO, which is seeking at least $5 billion -- although that IPO might not be ready until the second quarter.
Fourth-quarter IPOs in the sector include shopping site Groupon and gamer Zynga, whose games run on Facebook. Since the companies respective debuts, shares of Groupon have lost 24 percent and Zynga shares have risen 60 percent. Several others, however, have done better: Jive Software, a business social network specialist, have gained 55 percent, while security software provider Imperva has seen its shares vault 53 percent since its November debut.