If contracting parties enter into a verbal contract and the other contracting party subsequently sends the artist a written letter of confirmation of the content of such verbal contract, the artist should raise objections against any content that does not correspond to the preceding verbal agreement immediately. Otherwise, the artist’s inactivity (silence) can be interpreted as acceptance of the confirmation letter. This applies to e-mail communication as well.
Section 1740 of the Czech Civil Code stipulates that a contract is concluded by an affirmative response to an offer, even if it contains addenda or deviations from the proposal (offer) that do not change its content fundamentally. A contract is then considered to have been concluded in the wording of the addendum or deviation, unless the offeror refuses such changes without undue delay.
Thus, it may happen that, for example, a costume designer accepts a theatre’s draft agreement to complete a job with an addendum stipulating that the theatre will not pay an advance for the creation of costume designs. If the costume designer does not notice this addendum and does not refuse it “without undue delay”, the agreement will be valid in the wording of the addendum. The costume designer can, however, avoid such mistake in advance by proceeding pursuant to the provisions described in Section 1740(3) of the Civil Code, i.e. if he rules out the possibility of such changes beforehand when sending the draft agreement.