This study aims to address the question of impact of the loss of full legal capacity by a natural person on their ability to act as a commercial attorney and the legal consequences of the same. In particular, the analysis covers the decision on incapacitation of a commercial attorney as well as the consequences of the appointment of an interim advisor in court proceedings. In addition, the author looks at the consequences of acts in law by an attorney whose authorisation has expired due to the loss of their full legal capacity as well as discussing the above against the background of the so-called content of the legal relationship which is regarded as a causa of granted powers of attorney.