How big a problem is online ad fraud?

Half of ad impressions served to Internet Explorer were to “nonhuman” traffic, compared with 20.5 percent of impressions served to Google’s Chrome browser, claims a report from FraudLogix, as reported in The Wall Street Journal

FraudLogix reportedly examined a sample of 135 million individual online ad impressions for a week in July, analyzed the browsers to which the ads were served, and tracked the portion of those ads its technology determined were delivered to “nonhuman” or “bot” traffic, The Wall Street Journal says, adding that fraudsters are able to manipulate consumers’ web browsers for financial gain by infecting them with malware and forcing them to load certain web pages. 

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“For advertisers this is bad news, since they can wind up paying for ads which can never actually be seen by real people,” notes author Jack Marshall.

Both Microsoft and Google have pushed back on the report, WSJ says, countering that it isn’t possible to accurately measure fraud at the browser level. “Bots and malware often forge user agent strings to produce 'fake' traffic, which can’t be attributed to a particular browser,” Microsoft is quoted as saying. 

“When malware infects someone’s device or web browser in general, the infected machine may act as a fraudulent bot impersonating any browser, even if it isn’t installed on the infected machine,” Google is quoted as saying. “As a result, we’ve found that measuring ad fraud per browser has not been a helpful way of understanding this issue.”

Other browsers examined included Mozilla’s Firefox, Apple’s Safari and Microsoft Edge. Less than 5% of impressions delivered to all versions of those browsers were fraudulent, FraudLogix believes. The potential for fraud is higher for Chrome and Internet Explorer because of their widespread adoption; 16.2 percent of the traffic examined for the report was from Internet Explorer, compared with 61 percent from Chrome.