(1) Avoidance is effected by declaration to the opponent.
(2) The opponent is, in the case of a contract, the other contractual party and, in the case governed by section 123 (2) sentence 2, the person who has acquired a right directly under the contract.
(3) In the case of a unilateral legal transaction that was to be entered into in relation to another person, the other person is the opponent. The same applies to a legal transaction that is required to be entered into in relation to another person or to a public authority, even if the legal transaction has already been entered into in relation to the authority.
(4) In the case of any other kind of unilateral legal transaction, the person who has received a legal advantage directly on the basis of the legal transaction is the opponent. However, the avoidance may be made, if the declaration of intent was to be made to a public authority, by declaration to the authority; the public authority as a rule is to inform the person who was directly affected by the legal transaction of the avoidance.