Zuckerberg is adamant: Facebook is not building a phone

Facebook Chief Executive Mark Zuckerberg didn't mince words when he reiterated to analysts and investors that the social network has absolutely no intention of building its own mobile phone.

"We're not going to build a phone," he said during the social network's earnings call Wednesday. "It's not the right strategy for us to build one integrated system...Let's say we sell 10 million units -- that would be 1 percent of users. Who cares for us?"

I can think of plenty of people who care -- investors in particular. The company's stock, which has been fluctuating in after-hours trading, took another downward turn after the revelation and is currently trading about 4 percent down from its closing price of $31.24.

Zuckerberg's firm denial, a recurring theme on earnings calls, contradicts a smattering of Facebook phone rumors that resurfaced ahead of the company's Graph Search announcement earlier this month. Of course, that's not to say Zuckerberg and Co. don't have ambitious goals for getting Facebook more deeply enmeshed inside your smartphone. Quite the opposite, really, as Zuckerberg was also quick to point out.

"We have a billion people using our products, and we need to make Facebook really good across all the devices that they use," he said. "Rather than just building an app that's a version of the functionality that you have today, I think making it so that we can just go deeper and deeper is going to be a big focus for us."

What that means exactly, we don't know, but it's clear that Facebook intends to be a core component of mobile phone operating systems.

Zuckerberg's statements came after Facebook released a very strong fourth-quarter earnings report. Facebook made $1.59 billion in revenue and posted adjusted earnings per share of 17 cents in the fourth quarter. The company, which said it made 23 percent of advertising revenue from mobile, also proved for the second quarter in a row that it could monetize mobile attention.