The empirical accounts of the costs and benefits of quasi-parity codetermined supervisory boards, a very special German institution, have long been inconclusive. A valid economic analysis of a particular legal regulation must take the legal specificities seriously, otherwise it will be easily lost in economic fictions of functional equivalence. At its core the corporate actor “supervisory board” has no a priori objective function to be maximised – the cornerstone of the theory of the firm – but its objective function will only be brought about a posteriori – should negotiations result in an agreement (E. Fraenkel). With this understanding, the paper presents six recent quasi-experimental studies on the economic (dis) advantageousness of the German codetermination laws that try to follow the rules of causal inference despite the lack of random variation. By and large, they refute the hold-up model of codetermination by showing positive or nonnegative effects even on shareholder wealth – and a far-reaching improvement of the well-being of the core workforce. In conclusion, indications are offered that the shareholder primacy movement has only weakened, but not dissolved the “Deutschland AG”.