Interrogatories may be served upon any party at the time of service of the original process or at any time thereafter. The following resources include sample forms related to Pennsylvania interrogatories.Answers to interrogatories shall be in writing and verified. The answers shall be inserted in the spaces provided in the interrogatories. (a) (1) Answers to interrogatories shall be in writing and verified. Method of Service and Due Date of Responses. If personally served, responses to interrogatories are due within thirty (30) days of service. Here are some sample interrogatory objections, a cheat sheet that might help you determine how to object to interrogatories. (a) Describe the test procedures;. If personally served, responses to interrogatories are due within thirty (30) days of service.