Form Interrogatories are a list of questions on a court form. A party may serve on any other party no more than 25 written interrogatories, including all discrete subparts.These rules shall be known and cited as the Local Rules for the Superior Court of. California, County of Contra Costa. (2). The documents are listed in the Attachment to Proof of Service–Civil (Documents Served) (form POS-040(D)). This packet provides general guidance about asking written questions, called "Interrogatories," to another party in the case. Proof of service of moving papers must be filed no later than 5 court days before the hearing date.