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On November 17th, 2005, an anonymous Wikipedia user deleted 15 paragraphs from an article on e-voting machine-vendor Diebold, excising an entire section critical of the company's machines.

In this case, the changes came from an IP address reserved for the corporate offices of Diebold itself. And it is far from an isolated case. A new data-mining service launched Monday traces millions of Wikipedia entries to their corporate sources, and for the first time puts comprehensive data behind longstanding suspicions of manipulation, which until now have surfaced only piecemeal in investigations of specific allegations.

Voting-machine company Diebold provides a good example of the latter, with someone at the company's IP address apparently deleting long paragraphs detailing the security industry's concerns over the integrity of their voting machines, and information about the company's CEO's fund-raising for President Bush.