Swindlers have stepped up their effort to fleece millions of dollars from online advertisers who use lucrative marketing networks run by Google Inc and Yahoo Inc, according to a quarterly report to be released on Monday.

The sales referrals generated by clicks on the brief advertising links popularised by the two internet powerhouses are a sham 14.1% of the time, based on information collected from 1,300 online marketers.

That’s up from a click fraud rate of 13.7% three months ago, according to Click Forensics, a San Antonio-based consulting service that compiles the index.

The statistics jibe with other data asserting advertisers are paying a significant sum to Google, Yahoo and their partner web sites for phantom shoppers even as more resources are devoted to thwarting scammers.

A recently released survey of 407 online advertisers by market research firm Outsell Inc estimated click fraud cost advertisers $800 million last year.

Get the full story at The China Post