Snapchat's parent craters for the first time, drops more than 12%

Snap shares turned lower Monday after several analysts initiated coverage of the social media firm's stock as a "sell."

Shares of the parent company behind the popular messaging app Snapchat closed more than 12 percent lower, falling below the opening price from their first day of trading.

That's after shares were up nearly 2 percent in premarket trading.

Snap has had mixed reactions from the Street and has yet to receive a "buy" rating from any analyst listed in FactSet.

Analysts at Needham initiated coverage of the social media firm's stock with an "underperform" rating, noting the company's total addressable market is 80 percent smaller than Facebook.

"Prospect Theory would label SNAP a 'lottery-like' stock," they said in a note Monday.

Atlantic Equities, Morningstar, Nomura Instinet, and Pivotal Research also gave the social media company a "sell" rating.

Brian Wieser, a senior analyst at Pivotal Research, said in a note that Snap "is a promising early stage company with the significant opportunity ahead of itself. Unfortunately, it is significantly overvalued given the likely scale of its long-term opportunity and the risks associated with executing against that opportunity."

Two other firms — Aegis and Susquehanna — rated Snap a "hold" rating, however. Aegis cited in part Snap's slower user growth, like Twitter, and lack of an ecosystem.

Susquehanna said the company near-term could offer some upside potential.

"We also suspect that the company probably has some product innovations coming down the pike," Susquehanna analyst Shyam Patil said in a note. "We believe our numbers could have an upward bias, as well."

On Thursday, Snap began trading, closing its first day up 44 percent at $24.48 a share.

Shares jumped 10.6 percent more on Friday after NBCUniversal, the parent company of CNBC, confirmed that it had invested $500 million in Snap on its IPO day.

—CNBC's John Melloy and Tae Kim contributed to this report.