Section 541.4 - Properly issued invoices(a) A properly issued invoice is a demurrage or detention invoice issued by a billing party to:(1) The person for whose account the billing party provided ocean transportation or storage of cargo and who contracted with the billing party for the ocean transportation or storage of cargo; or(b) If a billing party issues a demurrage or detention invoice to the person identified in paragraph (a)(1) of this section, it cannot also issue a demurrage or detention invoice to the person identified in paragraph (a)(2) of this section.(c) A billing party cannot issue an invoice to any other person.