Delaware Certification of Unknown Defendant(s) (Form 33) is a form used when attempting to serve legal documents to a defendant or defendants who are unknown or cannot be identified. The form is completed by the plaintiff or plaintiff's attorney and is an affidavit asserting that all reasonable efforts have been taken to locate and identify the defendant or defendants. This form must be completed and filed with the court prior to the court issuing a default judgment against the defendant or defendants. There are three types of Delaware Certification of Unknown Defendant(s) (Form 33): Form 33A for individuals, Form 33B for corporations, and Form 33C for partnerships or unincorporated associations.