B. – Conditions under which depositions may be taken before an action is filed.
Persons who wish to deliver or elicit sworn statements outside of court should file a petition, or official notice in a U.S. district court. The court must be located in the district of the opposing, or ‘expected adverse’ party. This petition should: present the petitioner’s desire or expectation that the subject matter may be presented in a court of law, reveal the subject of the deposition, attest to the facts which the petitioner will endeavor to prove, divulge any opposing parties to the petitioner, and request a court order allowing depositions of those determined to be key to the contestable matter. There is no stipulation preventing a qualified legal representative from serving as the petitioner in representation of another party.
The petitioner, be it legal representative, potential plaintiff, or potential defendant, must also give advance notice of a hearing to the parties referred to in the petition. At this point, the court may intercede to facilitate the delivery of a deposition of those parties from whom it deems testimony to be pertinent.Source:
FEDERAL RULES OF CIVIL PROCEDURE
V. DEPOSITIONS AND DISCOVERY
Rule 27. Depositions Before Action or Pending Appeal
(a) Before Action.
(1) Petition. (2) Notice and Service.
http://www.law.cornell.edu/rules/frcp/