민사소송법상 권리주장참가에 대한 연구

This article examines the independent third-party intervention system, particularly focusing on the assertion of rights within this framework. Through comparative legal analysis, it has been identified that independent third-party intervention is a unique system found only in Japan and South Korea, with no equivalent in Germany or France. Originally, Japan's civil procedure law adopted Germany's principal intervention system, but it was later replaced by the independent third-party intervention system due to difficulties in achieving consistent judgments and the duality of procedures, which were not conducive to judicial economy. The issue lies in the fact that the independent third-party intervention system is bifurcated into rights assertion intervention and fraud prevention intervention, making it challenging to understand its nature uniformly. Rights assertion intervention is an evolved and modified version of Germany's principal intervention (Hauptintervention) system, while fraud prevention intervention has developed from France's third-party opposition (tierce opposition) system, making them inherently different systems. There is a need for separate legislation in the future. In rights assertion intervention, the concept of incompatibility of claims is not explicitly stated in the civil procedure law. It has only been accepted without significant disagreement based on interpretations from academic theories and case law. What is the extent to which rights assertion intervention should be recognized in cases of double sales of real estate? It seems that case law has been somewhat established regarding rights assertion intervention since the 1990s. In simple cases of double real estate sales, where two sales contracts exist, they can be deemed to coexist, and therefore, they are compatible and do not qualify as cases for rights assertion intervention. Even in cases of double sales where the second buyer engages in breach of trust, the fact that two sales contracts exist externally is undisputed, so it is also deemed compatible and not subject to rights assertion intervention. However, if the parties claim double sales but the intervener asserts that only one sales contract exists, the condition of incompatibility seems to be met because there is only one party to the sales contract. What happens if the intervener claims the second sale is invalid and asserts the validity of their own sales contract? In this case, the concept of incompatibility should be judged based on the written and explicit claim rather than the intent of the claimant, focusing on the essence of the claim. Therefore, even if the intervener argues for the invalidity of the second sale, if the first and second sales contracts coexist externally, this situation would still be considered compatible, and the requirements for independent third-party intervention would not be met. This aligns with the general interpretation in South Korean civil procedure law, where the substance of the legal system and principles are prioritized over the intentions of the parties in subjective and objective consolidation. Although the use of independent third-party intervention is not particularly high, it is commendable that a system has been established allowing a third party, other than the plaintiff and defendant, to assert their unique interests within the main litigation process. However, it is regrettable that despite the existence of the independent third-party intervention system, its complexity has led to limited practical use. In the future, in-depth research on the essence of the system is required, along with efforts to revitalize the system, including fraud prevention intervention.