It has been revealed that 83 million accounts on Facebook are categorised as 'fake'. This accounting for 8.7% of Facebook's 955 million users. It has long been known that there are a number of fake profiles on the social network but the actual number has never been revealed, until the company's filings were published this week that is. Upon reading the filing it doesn't appear to be as bad as first suggested. Facebook have categorised the fake accounts in to three categories; 'Duplicates', 'Misclassified', and 'Undesirable' with duplicates accounting for the highest proportion - 4.8%. Facebook defines duplicates as "an account that a user maintains in addition to his or her principal account", so they're not really fake accounts as such.

Misclassified accounts amounted to 2.4% of these accounts with Facebook describing these as "users have created personal profiles for a business, organisation, or non-human entity such as a pet", so again not exactly fake accounts.

What I would describe as real fake accounts amounted to just 1.5% of the 83 million with the company defining these as 'undesirable'. These are the accounts that send spam and other annoying content, they are the ones that breach Facebook's terms of service.

For an advertiser, having to spend huge amounts of money on potentially fake accounts isn't good news and this only adds to the worries that many have over Facebook's business model which relies heavily on targeted advertising.

This worry has has clearly been seen in the company's stock with around 50-60% being knocked off it's value since its IPO earlier this year. At the time of writing this the stock was down to $20.50 from it's peak of $40 on the day of it's IPO. The exact reasons for this drop in value are of course complicated but the news of these fake accounts almost certainly help the situation.

What people are waiting for next is news from Facebook about what they're going to do about these accounts.