Google earns between $32m and $50m (£18.7m and £29m) from placing its AdSense text adverts on 'typosquatting' sites, according to a Harvard Business School professor.

Companies will buy domains such as 'bbbc.co.uk' or 'bankkofamerica', hoping that users will misspell domain names when entering them in the browser window. According to Benjamin G Edelman, when users land on those pages, they click the Google AdSense ads that are on the pages, generating revenue for Google and the company that bought the domain name. The loser, says Edelman, is the company whose trademarks have been infringed.

There's another issue, too. Google offers a special AdSense system targeted specifically at parked domains. Does AdSense for Domains make Google responsible for typosquatters and their trademark infringement?

That's the question a new lawsuit hopes to answer. It accuses the search giant and various typosquatting companies of trademark infringement. However, the case is a long way from resolution.

Professor Edelman, who is a participating lawyer for the plaintiff in the class, wrote in the McAfee Security Journal (he is also an advisor for McAfee) that McAfee found 80,000 domains typosquatting on the top 2,000 websites and notes that several large companies, including Microsoft have gotten big settlements from typosquatting companies.

A Google spokesperson told The Industry Standard: "We believe that these claims are entirely without basis, and we are vigorously defending ourselves."