Group taxation (special schemes according to which a group of companies meeting certain requirements may be assimilated for tax purposes to a single company) exists in several European Member States and is now under consideration in an EU proposal concerning a common consolidated corporate tax base (CCCTB). Its rationale as a potential EU tax regime has arisen from a series of high-profile ECJ cases concerning cross-border tax relief claims--decisions which have been criticized for lack of clarity and for breach of freedom of establishment (Article 49 TFEU).