"Because it is there" may be a perfectly adequate response to the question of why you want to scale a mountain (although it invites the follow-ups of "are you crazy?" and "does your spouse know you spent four thousand dollars on climbing gear?"). It does not, however, cut it when a judge asks why you want a mountain of metadata.
The court in Dahl v. Bain Capital Partners, LLC, 2009 U.S. Dist. LEXIS 52551 (D. Mass. June 22, 2009) reminds us of this fact. In that case, a requesting party sought every last scrap of metadata associated with the electronically stored information produced by the other side. The producing party refused, instead offering to hand over just 12 fields of metadata. Ignoring the inevitable follow-up question, "Does your client know you spent four thousand dollars on a discovery dispute over metadata?", the requesting party took the issue before the court.
The Dahl court explained that the goal of discovery is still to uncover admissible evidence, no matter how many new and exciting areas of information may exist for attorneys and their clients to fight over. Not all metadata leads to admissible evidence, and so sweeping requests for metadata (regardless of its likely utility) are unnecessarily costly and burdensome -- a fact also recognized in the Rule 34 Advisory Committee Notes. Accordingly, the court ruled that the requesting party should tailor its metadata requests to specific word documents, emails, or sets of email in an effort to reduce the burdens of production, thereby increasing the likelihood of prudent and efficient litigation.
As has been noted on this very same website, about three inches down from this post, attorneys should be aware that a successful discovery process requires knowledge of both the technological peculiarities of ediscovery and the established procedures and limits of discovery. The Dahl opinion confirms that observation.