If the business is owned solely by one person, only that person needs to sign. If it is a partnership of two or more people (but not a formal legal entity), both or all of the "partners" must sign. If it is a legal partnership, any officer who has the authority to sign on behalf of the partnership may do so. If it is a corporation, an officer who has signatory authority must sign - which is usually the President, but not always. All signatures must be made in front of a notary or at the Town Clerk's Office.