Amazon and Yahoo have now both responded to Google's subpoenas regarding their work on book digitization projects, and both have given the same basic response: you can see our confidential documents when you pry them from our cold, dead hands. Amazon even went so far as to suggest that, instead of proprietary information, Google could learn all it needs to know from some press releases.

The current unpleasantness is a result of Google's own legal difficulties with the Authors Guild, which is suing the search giant over its decision to digitize copyrighted books and make them a part of its Google Book Search project. The Guild contends that this has to happen on an "opt-in" basis in which copyright owners must explicitly give Google permission to do the scanning and indexing. Google claims that the current opt-out system is both fair and legal.

In its quest to prove its case, Google subpoenaed Amazon, Yahoo, and Microsoft at the beginning of October, seeking more information about their respective book projects. Amazon already allows users to search inside of selected books on its website, while Yahoo and Microsoft are partners in the Open Content Alliance digitization project.

Both of these services rely on an opt-in approach to scanning copyrighted works, and Google demanded an incredible amount of information on each of them. Amazon responded in late October that it had no intention of turning over most of the requested documents, and told Google that some of the information in question was "described on Amazon.com's websites and in press releases."

Yahoo has just filed its own objection to the subpoena, saying, "There is simply no need for Google to be peering into the minds and computers of Yahoo employees."

As a result of the work done by all these companies, searching inside books has grown remarkably easy in the last few years—but searching inside your competitors' confidential file cabinets remains difficult.

Update

Yahoo's even less pleased about the subpoenas than Amazon, judging by their response. A copy of their legal filing seen by Ars Technica lays the smack on Google, saying that Yahoo "is not a party to the underlying action against Google relating to book scanning, does not have a book scanning program of its own, and has no information that is remotely relevant to the Google Action."

It goes on to say, "Whether Yahoo may ever have considered developing a 'Book Project' or Yahoo's mental impressions about the copyright status of any book is not admissible or relevant with respect to Google's pending dispute with book publishers."

Bascially, Yahoo points out that they are a member of the Open Content Alliance, but that the group is a separate entity not under Yahoo's control. The company "exercises no direction and control over the OCA's operation of its project."

The end result? Yahoo has no plans to give Google any documents, either.