By this measure, Facebook is 'cheap': Strategist

The words cheap and Facebook rarely share the same sentence. Shares of the social giant sport a PE near 80, and at $220 billion, its market cap over twice that of Boeing. But according to one top strategist, there is one measure that suggests the social giant could in fact be a bargain, and if she is right, Facebook investors could soon see new all-time highs in the coming months.

On CNBC's "Trading Nation," options expert Stacey Gilbert pointed to a growing disconnect between how analysts and investors are valuing Facebook as one reason to be bullish on the stock. Specifically, she noted that Facebook shares are trading at an 18 percent discount to the average analyst price target.

"Believe it or not, that's one of the biggest discounts we've seen in the past year in terms of where Facebook shares have closed versus the average price target," Gilbert, head of derivative strategy for Susquehanna said on Monday. According to FactSet, 88 percent of the 48 analysts who cover Facebook have a positive rating on the stock, with the average price target of $95.88. By Gilbert's work, Facebook's discount to its average price target is among the highest in the S&P 500, which she says is surprising given the company's high valuation.

"The sentiment on the Street is relatively positive," said Gilbert.

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What makes Facebook even more attractive, said Gilbert, is the fact that Facebook options prices are "trading historically one of the lowest levels we've seen in the past two years," said Gilbert.

So to take advantage of low options prices, Gilbert bought the July 80-strike calls for $2.66 each. Since buying a call gives one the right to purchase a stock for a given price at a set time, Gilbert's trade is profitable if Facebook rises above $82.66 by July expiration—that's 4.5 percent in the next two months.

"If I'm correct and Facebook rallies, I have unlimited upside exposure," added Gilbert.

Facebook shares soared more than 40 percent in 2014, but have been taking a breather this year. The stock is up a mere 1 percent year-to-date while the Nasdaq is up nearly 6 percent in the same period.

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