Facebook is an 'obvious' investment, even at peak monetization for core biz

If you're looking for a growth stock in the tech sector, Facebook is your best bet, according to Roger McNamee, co-founder of Elevation Partners.

"What I like about it is that the fundamental story is so good that if you like the market, Facebook is an obvious name to hold and in the tech sector, it's the one you hold if you're only going to own one for high growth," he said during a Monday interview on CNBC's "Squawk Alley."

McNamee explained that while Facebook isn't impervious to overall market moves, there are many reasons that the stock is a good investment. For one thing, he said Facebook's rate of earnings growth has blown away experts.

McNamee said that "what's been amazing is that the rate of earnings growth has accelerated in the last year" and that "the actual fundamental growth there has been so much greater than anyone expected."

But "Facebook can't sustain that forever," McNamee said. "The core business, the original Facebook platform, is approaching what I would characterize as peak monetization," he said, summarizing a popular concern. McNamee said, however, that the company's growth potential lies in opportunities in its other platforms.

"The beautiful thing is that they have gigantic properties in WhatsApp, Messenger and Instagram, where the levels of monetization to this point are somewhere between zero and very low," McNamee said.