(a) Availability; Number. Any party may serve written interrogatories directed to any other party. Unless the court orders otherwise, a party may serve one or more sets having a cumulative total of not more than 30 interrogatories to be answered by the same party. Interrogatories, however grouped, combined, or arranged and even though subsidiary or incidental to or dependent upon other interrogatories, shall be counted separately. Each form interrogatory contained in the Appendix to these Rules shall count as a single interrogatory.

(b) Response. The party to whom the interrogatories are directed shall serve a response within 30 days after service of the interrogatories or within 15 days after the date on which that party's initial pleading or motion is required, whichever is later. The response shall answer each interrogatory separately and fully in writing under oath, or shall state fully the grounds for refusal to answer any interrogatory. The response shall set forth each interrogatory followed by its answer. An answer shall include all information available to the party directly or through agents, representatives, or attorneys. The response shall be signed by the party making it.

(c) Option to Produce Business Records. When (1) the answer to an interrogatory may be derived or ascertained from the business records, including electronically stored information, of the party upon whom the interrogatory has been served or from an examination, audit, or inspection of those business records or a compilation, abstract, or summary of them, and (2) the burden of deriving or ascertaining the answer is substantially the same for the party serving the interrogatory as for the party served, and (3) the party upon whom the interrogatory has been served has not already derived or ascertained the information requested, it is a sufficient answer to the interrogatory to specify the records from which the answer may be derived or ascertained and to afford to the party serving the interrogatory reasonable opportunity to examine, audit, or inspect the records and to make copies, compilations, abstracts, or summaries. A specification shall be in sufficient detail to permit the interrogating party to locate and to identify, as readily as can the party served, the records from which the answer may be ascertained.

(d) Use. Answers to interrogatories may be used at the trial or a hearing to the extent permitted by the rules of evidence.

Source: This Rule is derived as follows:

Section (a) is derived in part from former Rule 417 a 1 and 2 and is in part new.

Section (b) is derived from former Rule 417 b 1 and 2.

Section (c) is derived from former Rule 417 f and the 1980 version of Fed. R. Civ. P. 33 (c).

Section (d) is derived from former Rule 417 d.