A party may serve on any other party no more than 25 written interrogatories, including all discrete subparts. Federal Rule of Civil Procedure 33 and Local Civil Rules 33.2 and 33.3 explain the requirements for interrogatories.To whom can I direct interrogatories? FRCP 33 permits a party to serve a set number of written interrogatories (or questions) directed to another party in the case. A certificate of service must accompany filed documents, indicating how, when, and to whom the service was made. This HowTo Guide addresses how to draft and serve responses to interrogatories in federal practice. Rule 33(a) is also amended to permit the service of interrogatories upon any other party. P. 26(b)(1), a rule that was most recently amended in 2015. (e) Motions to Strike. Rule 59(e) of the South Rules of Civil Procedure, which is "substantially" the same as the Federal.