Porsche and Lower Saxony are taking their fight for control of Volkswagen to court.

The sportscar and SUV maker is asking the state court in Hannover to strike out a clause in the Volkswagen constitution that says that a shareholder blocking minority is 20%, rather than the usual 25%. This would effectively block Lower Saxony’s influence over major decisions.

Lower Saxony’s stake is currently 20.1%, while Porsche now holds shares equivalent to a 74.1% stake.

Porsche is arguing that the change to the constitution should be made after the European Court of Justice ruled that a legal provision allowing the 20% right of veto is in breach of European Union law because it applies to just one company.

The 20% right of veto is enshrined in the so-called Volkswagen Law that the German government has recently rewritten in the light of the European court decision. The court only ruled on the Volkswagen Law, and not on the Volkswagen constitution.

According to one German news report, if the Hannover court rues in Porsche’s favour, Porsche could push for a ‘domination’ agreement, which would allow it to alter Volkswagen’s structure completely.