matter. As described in part two, there has been a progressive application of abuse of rights to various areas of Union law. However, it is clearer still that the concept of abuse as it has developed in Kofoed and Part Service is substantially different from the one which was developed in Cadbury Schweppes. Accordingly, both claim to be the EU concept of abuse. Since both cases, the small chasm which appeared in Halifax has widened even further. The difference is that under the CS criteria, any reason other than a tax advantage is enough to keep the abuse concept at bay, whilst in Part Service, if the tax reasons are of more importance than the non-tax reasons, abuse may be established. In dealing with situations outside of taxation, Vanistendael has noted that the decision in Centros is the example to keep in mind. The test in Centros highlighted the fact that establishing a company in a Member State whose company law rules are the least restrictive cannot in itself constitute an abuse of the right of establishment. This may be compatible with Cadbury Schweppes, but fundamentally incompatible with the decision in Part Service. The situations defining Cadbury Schweppes (a cross-border problem and fundamental freedom elements) and Halifax (the interpretation of a national tax rule) are also fundamentally different involving different tests. With this in mind, Vanistendael contends it is conceivable to have more than one concept of abuse. 6.2 After the VAT cases: should the abuse concept be codified? Turning to the question of whether or not the abuse concept as elaborated in the VAT cases should be characterised as a uniform national concept borrowed from EU law, Vanistendael focuses on the fact that the PS decision has made this obsolete. He argues against a possible codification at Union level, much unlike the Opinion of Advocate General Maduro in Halifax, which concerned balancing the prohibition of abuse against the principles of legal certainty. Instead, he argues it would be more appropriate for the Court>