Comparative research on rei vindicatio (proprietary claim)

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K17018
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Civil law
• Research Institution: The University of Tokyo (2019); Tohoku University (2016-2018)
• Principal Investigator: ABE Yusuke 東京大学, 大学院法学政治学研究科(法学部), 准教授 (20507800)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 所有権 / 物権的請求権 / 物権的返還請求権

Outline of Final Research Achievements

In Japan, dominant doctrine regards rei vindicatio as a claim to the possession which owner has lost or at least does not have at the moment. On the other hand, French doctrine regards rei vindicatio as a lawsuit in which plaintiff and defendant each insist on their ownership.
Based on the understanding above, this research program compared the Japanese and French legal doctrine, and found the possibility that, even under Japanese law, rei vindicatio may have various fonctions, which depend on whether the defendant possess the thing as its owner or not.

Free Research Field

民法

Academic Significance and Societal Importance of the Research Achievements

これまで、日本の民法学では、所有権に基づく物権的請求権のうち、所有者の物支配に対する妨害を排除する妨害排除請求権をめぐる議論が盛んであり、返還請求権も、その延長線上に置かれ、ただ所有者が占有を失っている点で妨害排除請求権と異なるに過ぎない、と考えられてきた。これに対して、本研究は、返還請求権に焦点を当て、これまで顧みられなかったその機能の多様性に着目することで、日本民法学の返還請求権に対する理解を深める、という学術的意義を有するものである。