Facebook confirmed on Thursday that it scans private messages for links and records them as likes, according to the Wall Street Journal and other news outlets. The revelation undermines not only Facebook’s commitment to remove phony links but the company’s very credibility.

Facebook has not kept secret its scanning of private messages for references to criminal activity. What is new is that it also looks for links and records those as likes. This practice gives the appearance that more people are liking more things on the social network.

Kashmir Hill of Forbes asked, “Do over 6,000 people really ‘Like’ the Placenta Teddy Bear, or is that just reflective of the number of times a link to that page has been sent around in horror?”

Facebook clarified the discovery, noting that the scanned links were counted as engagement, not endorsement. It also said there was a bug that had scanned links being counted as double, but it conceded that this was one of the ways it boosted the number of shares. 

But the main thrust of the statement was to stress that no private user information was shared. “Absolutely no private information has been exposed,” the company said, and “when the count is increased via shares over private messages, no user information is exchanged, and privacy settings of content are unaffected.”

This statement misses the point. Facebook’s practice of scanning messages and counting links as likes isn’t a privacy issue. It’s common knowledge that what users do online – even in so-called private messaging – is potentially public. Rather, Facebook’s activity raises a credibility issue. It shows that the company is fudging the numbers when it comes to advertising.

Last month, when Facebook said it may end up removing as many as 1% of all likes from the site because they were phony, experts were quick to note that the actual number of fraudulent likes, shares and comments was probably much higher, with some estimates exceeding 10% of all likes and shares on the site.

At the time, we suggested Facebook was merely going through the motions of cleaning up the site.

“It’s not in Facebook’s best interest to proactively solve this problem,” said Tom Corson-Knowles, an online marketer who consults with small-business owners on ways to promote products on social networks. “Facebook’s revenue is directly proportionate to the number of pageviews the site gets, and banning one percent of [pageviews] will cost the company a lot of missed ad impressions.”

The latest news is more than a suggestion of impropriety. it’s an outright confirmation.