Facebook has admitted that more than 80 million user accounts on the social network may be fake.
In a quarterly filing to the US Securities and Exchange Commission (SEC) Facebook said that about five per cent of its 955 million members have duplicate accounts and around 83 million accounts could be fake.
The news sent shares in Facebook below $20 for the first time, though the price climbed back to $20.04 by the end of trading. The social network floated in May at $38 per share.
Facebook is currently valued at around $58 billion, close to half the $104 billion that it briefly reached on the day shares went on sale.
In its SEC filing Facebook said: "While these numbers are based on what we believe to be reasonable estimates of our user base for the applicable period of measurement, there are inherent challenges in measuring usage of our products across large online and mobile populations around the world."
Facebook estimates that 8.7 per cent of accounts - around 83 million - are fake or duplicate accounts. That means Facebook's fake users outnumber the total users for Instagram, the picture sharing site Facebook bought earlier this year. Instagram has 80 million members.
In March, Facebook said it estimated that up to six per cent of user accounts were fakes or duplicates. The increase has come because Facebook is now also counting mis-classified accounts (2.4 per cent) and undesirable accounts (1.5 per cent) in its total.
Facebook also confirmed that users would be forced to adopt the new Timeline layout for their accounts by next week. The change in design has been voluntary until now.
Users across the site were annoyed about the forced change, which was announced earlier this year and significantly alters the way each member displays their personal information.
One user wrote: “I’m sorry but this is rubbish. I’m surprised Facebook hasn’t included a compulsory DNA profile section (default to public obviously).”
i always hated facebook