Confirmation is the act by which the person who could rely on nullity waives it. This act mentions the subject-matter of the obligation and the defect affecting the contract.
Confirmation can only take place after the contract has been concluded.
Voluntary performance of the contract, with knowledge of the cause of nullity, is equivalent to confirmation. In the case of violence, confirmation can only occur after the violence has ceased.
Confirmation entails renunciation of pleas and exceptions that could have been opposed, without prejudice nevertheless to the rights of third parties.