The Social Chain Group claims Like-Wise, which launched today, identifies how much of an influencer’s engagement is real and how much is fake.
It collects data from the largest engagement bot farms, and builds a database of the tens of millions of fake profiles which replicate engagement behaviour by automatically liking and commenting on influencers' posts.
When Like-Wise identifies suspicious activity focused on a particular influencer, it uses artificial intelligence-powered tech to benchmark their engagement over time against real, organic engagement by human beings.
The tool purports to understand what paid promotion, shout-outs and other known algorithmic factors look like.
The industry-accepted method of measuring influence is "engagement per post", but fraudsters can easily game this metric by using popular apps which allow them to buy likes, view and curate comments.
Social Chain said it has trialled the tool with several major brands and found that in one case an influencer who charges $1,000 (£766) per post had a fake engagement rate of 96%.
The company, who has given this influencer the pseudonym "Jess", claimed "Jess" has scammed more than 20 brands including major high street names.
The agency audited 10,000 influencers who are frequently called upon by brands and agencies in social media campaigns. It found that more than one in four of influencers have engaged in this type of manipulation or fraud.
The launch comes within months of Unilever’s global marketing chief Keith Weed announcing at Cannes Lions in June that the FMCG giant would no longer work with follower-buying influencers.
Despite industry concerns over influencer fraud, business is booming: the size of the global Instagram influencer market is set to grow to $2.38bn next year, according to Statista, more than double what it was in 2017 ($1.07bn).
But Steve Bartlett, the founder and chief executive of Social Chain, said a huge industry of social influencer fraud had come about because people were driven to use them "blindly".
Bartlett told Campaign: "From what I know about the deep dark shadows of what's possible, the follower number means nothing: it isn't relevant or interesting."
"There are literally thousands of influencers who are making a full-time living out of creating the appearance of having a big audience, when in several cases 95% of their engagement is fake," Bartlett said. "In real terms, you’re paying $1,000 to get 1,000 people to act, but really if I only get 50 people to act I’m stealing $950."
"When we went through how frequent it is, it’s incredible. Some of these people belong in prison because what they’re doing is fraud.
"There are major brands paying some people thousands of pounds for fake influencers to be flown around the world, when they literally have zero influence. Zero. There’s more influence in my dog’s Instagram page than some of these people that are making full-time living."
Bartlett said many marketers had been driven "blindly" to social media influencers and were victims of "not knowing what you don’t know".
He said: "The people spending the budgets, marketing directors and chief marketing officers, they are less connected to ensuring they get an effective return or what they should be tracking. They will measure a like or a view number against a KPI, for example."
Marketers’ jobs are made more difficult by there being no benchmark pricing model for buying influencers, who are usually priced by how long they are willing to post for, Bartlett added.