Comparing Search Data Retention Policies of Major Search Engines

Well, according to Microsoft.

As part of the on-going battle among major search engines related to search data retention policies, Microsoft has published this chart attempting to summarize and compare the state of anonymization in the search industry (click to enlarge).

Few techncial details about how the companies enforce these policies have been made public, and as Joris van Hoboken reminds us, de-identification is not the the same as anonymization. There’s good work to be done to confirm, validate, and test the procedures claimed by each of the major search engines.