등가성 장애에 관한 연구

A Study on Equivalence Obstacle - focused on the discussion in Germany

Contract extinction is the ultima ratio that could be allowed in a case where proper contract benefits do not exist to each contracting party any more. Contract extinction is determined by testing whether contract benefits exist or not. Contract extinction include two types: rescission of contract and cancellation of contract. Rescission is to aim to put contracting parties in the original positions before contract, considering changes of circumstances. Rescission applies only to a contract that could be performed in a short period of time. On the other hand, cancellation is to terminate contract relations in the future in a contract that should be performed continuously for certain period of time. However, the principle of pact sunt servanda should be observed. The change of contract on special conditions must be recognized only in an exceptional case. Contracting parties are required to perform original obligations. Equivalence of contract is breached if a change of contract is allowed. Equivalence obstacle belongs to risk of contract which contracting parties should undertake. Amendment of equivalence obstacle, therefore, has exceptional characteristics. Two circumstances that could lead to amendment of contract are change of circumstances in contract and important circumstances in cancellation. This research is to study the legal regulation on contract extinction from the point of view of change of contract. Especially, the 2009 civil code proposals include the general regulation on cancellation and the principle of change in circumstance. This study reviews the concept of equivalence obstacle, the standard of equivalence obstacle, and especially, equivalence obstacle as a justification of cancellation of contract.