Microsoft and Yahoo handed over search engine data to the U.S. government after a request - but Google denied to do so. Forbes takes a look why Google decided to deny:
But it's more likely that Google is worried about the results of its search queries and not the technology that powers them. The compromise the Department of Justice has worked out with Google's rivals calls for the search engines to let the government see how often certain search terms were used, but won't let it look up specific IP addresses to what individuals looked for.
That alone could prove embarrassing enough for Google. A public disclosure of exactly how much pornography is on the Internet and how often people look for it--the two data points that will result from fulfilling the government's subpoena--could serve to make the Internet look bad. And Google, as its leading search engine, could look the worst.