Hendrik Riehmer, the former chief executive of Berenberg Bank, has initiated legal proceedings against the German financial regulator BaFin.
The lawsuit challenges the extraordinary supervisory order that forced Riehmer to step down from his executive role at the Hamburg-based institution.
The move marks a significant escalation in the dispute between the ousted CEO and the supervisory authority.
By taking the matter to court, Riehmer is contesting the validity of the regulatory intervention that stripped him of his duties.
This legal challenge introduces a new variable into the ongoing turmoil surrounding the bank's management structure.
Berenberg Bank has been navigating a period of intense regulatory scrutiny following the initial removal of its top executive.