The largest advertising company on the Internet, Doubleclick, is being sued by a Californian woman over its use of cookies. The suit alleges that the Doubleclick cookies -- programs that store information about visitors to Web sites -- have been culling personal information from PC users without their prior knowledge or consent. The suit also claims that this information, which includes names, addresses and financial status, has been sold on in some cases. While cookies have become a common-place part of life on the Net, Doubleclick stands accused of using its direct marketing arm -- Abacus Direct, which it bought last year -- to turn the innocuous cookie into something altogether more powerful and more intrusive. Abacus is said to hold personal data relating to some 90 per cent of US households. The suit -- Judnick vs Doubleclick -- was filed yesterday in the California Superior Court, Marin County by the Rothken Law Firm, acting on behalf of Harriet M Judnick. It alleges that Doubleclick claims that no personal data is collected via cookies. According to Ira Rothken, one of the plaintiff's lawyers, Doubleclick has a duty to tell Net users what information about them might be collected in this way and that this consent must be gathered in an open and obvious manner. The lawsuit hopes to prevent Doubleclick from collecting personal data via cookies unless users have given prior consent. It also wants a mechanism set up whereby users can destroy any personal information about them gathered in this manner. Rothken was quoted by the news wire service Business Wire as saying: "Doubleclick has an obligation to the General Public using the Internet to truthfully and adequately inform them about what Doubleclick is taking from them, namely, their personal, private information." He continued: "Internet users have a right to privacy and to be free from false and misleading advertising, protected by the laws of the State of California." ®