How search engines rate on privacy | CNET News.com CNET has done a nice little study on the privacy policies and practices of the top 5 search engines. Their results show that their privacy policies leave a lot to be desired. In particular, Google and Yahoo never actually delete search data, and only partially "anonymize" it after over a year. As has been proven many times, the "anonymized" data can still be easily used to identify the actual identity of the searcher.