How firms buy fake 'likes' for Facebook at 'click farms'

How much do you like courgettes? According to one Facebook page devoted to the vegetable, hundreds of people find them delightful enough to click the "like" button - even with dozens of other pages about courgettes to choose from.

There's just one problem: the liking was fake, done by a team of low-paid workers in Dhaka, Bangladesh, whose boss demanded just US$15 per thousand "likes" at his "click farm". Workers punching the keys might be on a three-shift system, and be paid as little as US$120 a year.

The ease with which a humble vegetable could win approval calls into question the basis on which many modern companies measure success online - through Facebook likes, YouTube video views and Twitter followers.

British Channel 4 television's Dispatches programme will today reveal the extent to which click farms risk eroding user confidence in what had looked like an objective measure of social online approval. The disclosures could hurt Facebook as it tries to persuade firms away from advertising on Google and to use its own targeted advertising, and to chase likes as a measure of approval.

That particular Facebook page on courgettes was set up by Dispatches to demonstrate how click farms can give web properties spurious popularity.

"There's a real desire amongst many companies to boost their profile on social media, and find other customers as well as a result," said Graham Cluley, an independent security consultant.