A Member State to which workers have been posted may, in the case of fraud and under certain conditions, ask the courts to disregard an A1 certificate and apply its own social security legislation, including the recovery of contributions.

Member States may not impose mandatory liquidation on companies that wish to transfer their registered office to another Member State. A restriction on freedom of establishment may be justified by overriding reasons in the public interest, such as the protection of the interests of creditors, minority shareholders and employees, but a general mandatory liquidation goes beyond what is necessary to achieve the objective of protecting these interests.