Facebook "likes" are being added to webpages even if a user has not clicked a like button, or even visited the page in question, the company has admitted.
'Like fraud'
The site explained that the figure represented how many times an item was shared - not how often users had clicked "like" on the page.
However, the number appears next to the word "like" and the site's distinctive thumbs up icon.
One expert told the BBC the findings were "disturbing".
"Something intended for one purpose is being used for something completely different," said Prof Alan Woodward from the University of Surrey.
"What else is being done automatically that we don't know about?"
