The Bank guarantee case or Bürge (19 October 1993) BVerfGE 89, 214 is a German contract law case, concerning the interpretation of private law, and particularly the law of contract, in a way that is compatible with basic human rights principles. It was held that the power of freedom of contract must be interpreted in a way that protects people's genuine (rather than formal) autonomy, in those situations where there is a structural inequality of bargaining power.