Business Week has an interesting article on the technology the Associated Press and other media outlets are using to find and identify their copyrighted content on the Internet: Bloggers: Big Media Is Watching.

The AP, a not-for-profit news cooperative owned by thousands of subscriber newspapers, has been using a system from Redwood City (Calif.)-based startup Attributor. Like other content recognition systems, Attributor’s software extracts a small digital fingerprint—a string of bits unique to a given article, song, or video—and collects them in a database. Then it continually crawls billions of Web sites and blogs, much as Google does when a user launches a search, to detect where that fingerprint recurs. In the recent incident, AP had unearthed instances where its content—at times whole articles—was posted to the liberal-leaning Web site Drudge Retort. Other Attributor customers include Thomson Reuters (TRI), Condé Nast Publications’ CondéNet, and the Canadian Press. The AP and Attributor declined to comment on the incident.