While it is easy to obtain the consent of the contemptuous and the purchaser, it may be more difficult to obtain the agreement of the other party of origin: in a novation, the initial contract is extinguished and replaced by a new contract in which a third party assumes rights and obligations duplicated by one of the original parties. Novation does not remove prior rights and obligations arising from the original contract, although the parties may agree on them. These are indeed sales or transfer contracts under which certain rights are held by the seller (e.g. .B. for the purchase of the awarded work or the use of the work in specific places only). Novation is only possible with the agreement of the original parties and the new party.