According to a Czech Supreme Court decision (file no. 20 Cdo 1299/2019) handed down on 21 May 2019, if there are any doubts about the genuineness of a power of attorney, proof of its authenticity should be provided by the authorised representative (agent) or the represented entity (principal). The signatures on a power of attorney do not need to be officially verified. Even so, it should be borne in mind that since a power of attorney is a private document, it is up to whoever presents it to prove its genuineness and correctness. This rule applies not only when assessing the authenticity and accuracy of a private document presented as proof in court but also to private legal transactions if the person asked to accept the power of attorney has doubts about its genuineness or correctness.
If neither the principal nor the agent proves the authenticity and accuracy of a power of attorney by the time of the relevant transaction, the person asked to accept it may demand such proof and, until the same is provided, they are not obliged to negotiate with the agent or pay that person any debt demanded on behalf of the principal. The duty to prove the authenticity and accuracy of the authorisation rests with the agent or the principal. As such, the entity asked to accept it is not obliged to actively search for evidence of its genuineness or correctness.