By Matt Krantz, USA TODAY

Shares of Facebook soared $1.50, or 7.7%, to $20.93 as investors turned more bullish on the No. 1 social networking company's prospects following comments by CEO Mark Zuckerberg Tuesday.

During a TechCrunch Disrupt conference in San Francisco, Zuckerberg remained optimistic about the company's prospects, especially as it looks for ways to make money from users who access the system on mobile devices. He also conceded that the performance of the stock since the May IPO has been "disappointing." These comments pleased investors who feared Zuckerberg wasn't paying enough attention to shifting users to mobile nor to the stock.

Wednesday's gain by Facebook was the stock's best day, on a closing percentage-change basis. It was the best dollar-value gain since June 15, when shares of Facebook added $1.72 apiece.

Before Wednesday, Facebook hadn't closed above $20 a share since Aug. 20.

Shares of the stock, though, are still down 45% from the $38-a-share IPO price.

Read or Share this story: http://on.ksdk.com/18wIqes