A major challenge in Product Lifecycle Management (PLM) is the exchange of product data across lifecycle phases, information systems, and parties as data formats, structure and quality can vary vastly. Existing approaches focus only on certain phases of PLM, predominantly design and manufacturing, while the subsequent phases of usage/maintenance and disposal are often ignored. However, especially the usage phase is becoming increasingly important for revenue as customer expectation for services beyond the initial purchase of a product is growing. This paper proposes an ontology CO-PLM based on the foundational ontology DOLCE+DnS Ultralite to provide a formal basis for PLM. In contrast to existing approaches, CO-PLM follows an holistic approach covering all phases of PLM and integrates patterns from existing core ontologies