Newspaper publishers are taking the Gator online advertising network to court to prevent it selling pop-up ads on their websites without permission.
The Washington Post, The New York Times, Dow Jones and seven other publishers have joined forces to prevent Gator selling ads on their websites.
At the heart of the complaint is a program called OfferCompanion which is bundled with Gator's advertising software. OfferCompanion monitors web-surfing behaviour and delivers targeted pop-up ads to viewers.
If a user visits the Wall Street Journal site they receive a pop-up ad directing them to a rival who has bought an advertisment with Gator.
The publishers said that Gator was violating the publishers' copyright and trademark rights.
But Gator said it had the right to display targeted pop-up advertising, provided it had the permission of the consumer.
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