
In August, at a time when Facebook was valued at around $15bn (£10bn), Facebook proposed letting employees sell a proportion of their shares.
However, Facebook chief executive Mark Zuckerberg reportedly told staff: "I'm writing this note to let you know some bad news. Despite a lot of work, we have not been able to finalize a plan for the employee stock sale we announced in August."
He added: After carefully considering the current environment, we've decided to establish an open-ended time-table for an employee stock sale program."
Last year, Microsoft took a $240m (£164m) stake in Facebook for a reported 1.6%, which valued the social network at $15bn. But as the value of stocks across all sectors fell with the credit crunch, Facebook opted to resist a share sale.
The news comes as questions surround the value of social networks to advertisers. This week, a report found that more than half of chief marketing officers say they are not interested in incorporating social networking sites into their marketing strategies.
Last month, Procter & Gamble's head of marketing, Ted McConnell, said companies should not advertise on Facebook, maintaining that social networks had no right to monetise their customers’ conversations. McConnell, P&G's general manager, interactive marketing and innovation, said marketers should not "hijack" their customers and that it was "arrogant" to monetise social networking platforms.