A digital movie can be created jointly under the cooperation of many creators. It is then necessary to provide protection to the creatorship of each participating creator. In this paper, we propose a framework for providing the creatorship protection of multiple creators involved in creating the object-based digital movie. The proposed framework makes use of digital watermarking techniques and cryptographic protocols to achieve the creatorship protection purpose. Object-based movie may consist of several audio and video objects, which may be created by different creators. The proposed framework embeds different watermarks in different video/audio objects in such a way that each creator can show the joint-creatorship of the movie; as well as each creator can prove his/her creatorship of video/audio object he/she created.