Facebook stock cracks $40—now what?

Facebook stock broke above the $40 mark Friday, and the stock could have farther to go on mobile monetization, Tim Seymour of EmergingMoney.com said on CNBC's "Fast Money."

"I do think this is happening," he said, noting that the company had seen a 41 percent growth in its mobile ad revenue over the second quarter.

That growth rate, combined with the low institutional ownership, would likely push Facebook stock higher, Seymour added.

"If you get that growth rate in the third and the fourth quarters, this stock's going a lot higher," he said.

(Read more: Facebook is a 'great long-term holding,' says pro)

"In terms of the momentum factor, this stock is, I would say, at a place where there are a lot of people who actually don't own it still. I think there are a lot of shorts that have to be covered, and I think it's a place where a lot of institutions are looking."

Shares of Facebook closed more than 5 percent higher at $40.55 per share.

StockMonster's Guy Adami preferred another social media play.

"I still think LinkedIn is still the best name to be in," he said. "People will shoot against it on valuation, and at some point they're probably going to be correct, but the stock has been, with minor exception a few months ago, Teflon."

Brian Kelly of Brian Kelly Capital said that Zynga "still doesn't make a lot of sense. I understand they have a lot of cash, but that's really all they have."

Kelly cited businesses that the "Farmville" creator had announced it would enter and then dropped.

"That is a name that I would stay away from," he added.

By CNBC's Bruno J. Navarro. Follow him on Twitter @Bruno_J_Navarro.

— CNBC's Torrey Kleinman contributed research to this report.

Trader disclosure: On Aug. 23, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Steve Grasso is long BA; Steve Grasso is long BAC; Steve Grasso is long BBRY; Steve Grasso is long GDX; Steve Grasso is long GOOG; Steve Grasso is long HERO; Steve Grasso is long HPQ; Steve Grasso is long MHY; Steve Grasso is long LNG; Steve Grasso is long MJNA; Steve Grasso is long NVIV; Steve Grasso is long PFE; Steve Grasso is long QCOM; Steve Grasso is long S; Steve Grasso is long ASTM; Steve Grasso is long POT; Steve Grasso is long DECK; Steve Grasso is long DHI; Brian Kelly is long EURO ; Brian Kelly is long OIL; Brian Kelly is long AUSSIE DOLLAR; Brian Kelly is short US DOLLAR; Guy Adami is long C; Guy Adami is long GS; Guy Adami is long INTC; Guy Adami is long MSFT; Guy Adami is long AGC; Guy Adami is long NUE; Guy Adami is long BTU; Tim Seymour is long BAC; Tim Seymour is long CLF; Tim Seymour is long F; Tim Seymour is long GM.