Facebook's stock has passed its 38 dollar (£25) flotation price for the first time since its rocky public debut last May, crossing a symbolic hurdle that has eluded it for more than a year.
Shares of Facebook increased 1.2% to 38.08 dollars in morning trading in the US. That is the highest the stock has traded since the company's highly anticipated initial public offering (IPO) ended with a thud. The stock is up by more than 50% since last week.
The world's biggest online social network has been on a roll since reporting stronger-than-expected earnings on July 24. Investors are especially upbeat about its fast-growing mobile advertising revenue.
Facebook's ability to grow mobile revenue was one of the biggest concerns in the weeks leading up to its IPO last year. Investors were worried that its ad business was not migrating to mobile gadgets as quickly as its user base. Facebook urged patience.
In the April-June quarter, Facebook derived 41% of its ad revenue from mobile advertising. That is up from zero in the spring of 2012 and from 30% in the January-March quarter of this year. CEO Mark Zuckerberg said last week that the company has "made good progress growing our community, deepening engagement and delivering strong financial results, especially on mobile".
Still, Facebook has room to grow. Research firm eMarketer expects Facebook to increase its mobile advertising revenue more than fourfold to more than two billion dollars this year. This would give the Menlo Park, California, company a 13% share of the global mobile ad market, up from about 5% last year.
Facebook is currently number two in mobile ads, well behind Google. EMarketer estimates that Google had a 52% share of the global mobile ad market last year. This year, the firm expects Google's share to grow to 56%.