Variant rich production of individualized products and customer solutions results in new challenges for all involved industrial information systems in a producing company. To keep pace with the new requirements of a volatile future market and to exploit benefits of flexible digital production environments, it is crucial to adapt integration concepts of Industry 4.0, e.g. enhance information exchangeability by improving interconnectivity between software solutions, utilize all sources of data from a products production and use phase, and maintaining an up-to-date digital twin of the product and production assets.This paper presents an integration concept for the interaction between Product Data Management (PDM) systems, Manufacturing Execution Systems (MES) and shop floor level client systems. It addresses the gap of information flow between the different involved key software tools in a twofold manner. On the one hand side, specific information gained from production and use phase data of products have to be looped back to the PDM system. This sets the foundation for a better understanding of production planning and execution as well as use phase issues related to the engineering phase where problems have to be addressed for continuous product improvement. On the other hand, a direct information flow from PDM to MES and shop floor clients is defined to enable forwarding of current variant product instance information. To evaluate the practical applicability and additional value of the developed integration concept, a case study with an industry partner is conducted.