A party may serve on any other party no more than 25 written interrogatories, including all discrete subparts. This packet provides general guidance about asking written questions to another party in the case.If there are multiple parties, you can serve up to 30 interrogatories to each party. Read the Rule: Md. Rule 2-421(a). Any party may serve upon any other party written interrogatories relating to any matters which may be inquired into under R. -2. A party may serve on any other party no more than 40 written interrogatories, including all discrete subparts. This packet provides general guidance about asking written questions, called "Interrogatories," to another party in the case. Interrogatories are a helpful tool for discovery. Interrogatories are written questions which focus on any information relevant to the case. Interrogatories are written questions that either the defense or the plaintiff involved in litigation can send to the opposing attorney.