Under § 77 of the German Stock Corporation Act, the members of a management board run the company together: sämtliche Vorstandsmitglieder nur gemeinschaftlich. The articles or the board’s own rules may provide otherwise, and in practice they assign portfolios to individual members. The member who holds a portfolio is then fully liable for the decisions in it.
The other members keep their part. In the words of one law firm, the principle of overall responsibility nicht durchbrochen, sondern vielmehr modifiziert, is not broken but rather modified.