In this paper, we describe a new framework for watermarking 3D objects via their contour information. Unlike most conventional 3D object watermarking techniques, for which both insertion and extraction of the mark are performed on the object itself (3D/3D approach), we propose an asymmetric 3D/2D procedure. The goal of our work is to retrieve information (originally hidden in the apparent 3D silhouette of the object) from resulting images or videos having used the synthetic object, thus protecting the visual representations of the object. After developing theoretical and practical key-points of this 3D object watermarking scheme, we present the results of some preliminary experiments.