Del. Code tit. 10 § 3916
In any action arising out of the operation of any vehicle, in which it is alleged that the operator of the vehicle was a servant, agent or employee of the defendant or defendants, the plaintiff may specifically require the defendant or defendants to deny the allegation that the operator of the vehicle was a servant, agent or employee of the defendant or defendants by affidavit filed with the answer, by the specific notation of the need for denial by affidavit within the paragraph alleging that the operator of the vehicle was a servant, agent or employee of defendant or defendants. Any defendant so answering shall deny that the operator of the vehicle was operating the vehicle at the time of the occurrence as a servant, agent or employee of the answering defendant, and/or deny that the operator of the vehicle was operating the vehicle in and about the course of duties as a servant, agent or employee of the answering defendant and set forth the factual basis for the denial. Where plaintiff has complied with this section, failure of a defendant to file an affidavit with the answer shall be deemed an admission that the operator of the vehicle was a servant, agent or employee of the defendant.
10 Del. C. § 3916