Wikipedia Scanner, 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.

CalTech graduate student Virgil Griffith downloaded the entire encyclopedia, isolating the XML-based records of anonymous changes and IP addresses. He then correlated those IP addresses with public net-address lookup services such as ARIN, as well as private domain-name data provided by IP2Location.com.

The result: A database of 34.4 million edits, performed by 2.6 million organizations or individuals.