When it is made explicit by someone, knowledge becomes information source of knowledge for someone else. Thus knowledge sharing cannot be reduced to information sharing. The aim of this paper is promote knowledge sharing, whether tacit or "explicited" by individuals within extended enterprises. Product Lifecycle Management (PLM) systems aim at an integrated management of all product‐related information and processes within extended enterprises throughout the entire lifecycle of a product. In this paper, we propose (1) to outline a semantic interoperability between a collaborative platform and a Product Lifecycle Management (PLM) system, and (2) to highlight the conditions under which a piece of information shared through a PLM system may lead to one and only one interpretation. Step (1) allows individuals to construct a shared understanding, supporting tacit knowledge sharing, whereas step (2) leads to ensure explicited knowledge sharing, i.e. knowledge that has been made explicit by someone within a certain context. PLM systems are strongly integrated within extended enterprises and their use will illustrate in this paper how our approach supports knowledge sharing. The conditions and limits of our approach, as well as its study within industrial fields, are discussed at the end of this paper.