The satisfactory operation of the multi-stage type-approval requires joint action by all the manufacturers concerned. To that end approval authorities must ensure, before granting first and subsequent stage type-approvals, that suitable arrangements exist between the relevant manufacturers for the supply and interchange of documents and information, so that the completed type of vehicle meets the technical requirements of all the relevant regulatory acts listed in Annex II. Such information must include details of relevant system, component and separate technical unit type-approvals and of vehicle parts that form part of the incomplete vehicle but have not yet been type-approved.

Each manufacturer involved in a multi-stage type-approval shall be responsible for the approval and conformity of production of all systems, components or separate technical units manufactured or added by that manufacturer to the previously built stage. The manufacturer of the subsequent stage shall not be responsible for objects that have been approved in an earlier stage, except where that manufacturer modifies relevant parts to such an extent that the previously granted type-approval becomes invalid.