Here's The Massive Valuation Moving Facebook Stock

Facebook Inc FB shares are up more than 3.5 percent in Thursday's trading after bullish comments from an analyst at Cowen.

John Blackledge, who holds a price target of $91 with an Outperform rating on the stock, called Instagram a "rising social star," adding that the photo-sharing platform "is a valuable asset...given its large, fast-growing and highly engaged user base."

That asset, the analyst added, is "drawing significant advertiser interest," according to recent surveys conducted by Cowen.

Along with user growth forecast to double by 2020, Blackledge estimated Instagram to be worth $33 billion. Facebook itself is worth another $140 billion, while Facebook Messenger is valued at $10.5 billion, he wrote.

Related Link: Facebook Stock: Technical Alert

On a valuation basis, Facebook trades at $142 EV per MAU, above Twitter Inc TWTR ($104), but below Google Inc GOOG ($238), Blackledge explained.

Summing up his thesis, the analyst provided three potential catalysts for this year:

• Mobile ad revenue growth
• Video advertising
• Instagram monetization