Del. Code tit. 6 § 3101
No person, firm or association shall engage in, prosecute or transact any business within the limits of this State, by using any trade name or title which does not disclose the legal name of such person, or in case of a firm or association, the legal name of each and every person comprising the firm or association without, in addition to what is otherwise required by the laws of this State, first filing a certificate under the hand of such person or, in case of a firm or association, under the hand of one of the members of the firm or association, with the Division of Revenue, designating the trade name or title and the legal name of such person, or, in case of a firm or association, the legal name of each and every member comprising the firm or association. All certificates shall show the date when the partnership or association was organized, to which certificates there shall be attached the affidavit of the person signing it to the effect that the facts therein stated are true and correct.
6 Del. C. § 3101