关键词: 合同效力先决案件; 诉讼形态; 既判力; 确认之诉; 诉的合并

Abstract: The successful settlement of civil contract validity precedent cases needs to explore its specific litigation form. Contract validity as a substantive precedent issue is “slightly local” and plays a unique role in China's civil procedure. Traditionally， the handling of contract validity precedent cases was done in different ways according to the procedural role of contract validity. At present， the arbitrary expansion of the objective scope of the res judicata and the omission of the combined form of the lawsuit， are the main sources of the problems of the traditional handling mode. In this regard， there is a better way to do paradigm reconstruction: pull the objective scope of the res judicata back to the identity of “the object of action-res judicata”， and further determine the complete combined form of the lawsuit according to the substantive law rights system while transforming the contract effect into the object of action. This presents the reasonable litigation form of contract validity precedent cases—combining the lawsuit of affirmation and two real lawsuits of preparatory consolidation. Naturally， this kind of litigation form realizes the function of the consolidation of the lawsuit， and it is the “trapping potential” of the existing litigation system.

Key words: contract validity precedent case; litigation form; res judicata; lawsuit of affirmation; consolidation of the lawsuit