Google drawn into piracy row over copyright allegations
News Corporation, Viacom, Walt Disney and Time Warner are among a group of leading media that have accused Google of encouraging copyright theft.
The accusation emerged in a court case in the US surrounding five defunct movie download websites.
The media companies have accused Google of knowingly encouraging copyright theft by suggesting to illegal movie download sites that they place ads to appear on the search engine in response to search terms such as "pirated" and "bootleg".
The sites allowed users to download Hollywood movies such as 'The Incredibles', 'Charlie and the Chocolate Factory', 'Meet the Fockers' and 'Mr & Mrs Smith' in their entirety.
However, Google has hit back at the claims. A spokesman said: "We prohibit advertisers from using our advertising program to promote the sale of copyright-infringing materials.
"Hundreds of thousands of advertisers responsibly abide by our ad content policies and we're committed to preventing those who don't from using our program."
Legal documents allege that Google accepted ads and endorsed "sponsored links" from the websites' operators.
The row is the latest setback in a tense relationship between media companies and Google. Television companies and film studios have been struggling to agree deals to control the way their content is viewed on YouTube, which was acquired by Google last year in a $1.6bn deal.
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