The circular economy (CE) is an economic philosophy aimed at eliminating waste and the continual use of resources. It emphasises designing products for longevity, reuse, and recycling to create a closed-loop system. One of the goals of enterprise modelling (EM) is to support enterprises in change processes from the current situation into a desired future state. In the context of the transition to the CE, the question arises if and how EM methods and languages must be adapted for the CE. The main contributions of this work are a better understanding of the challenges manufacturing enterprises face when preparing their product architectures for the circular economy, a meta-model preparing the product perspective in EM methods for CE, and an investigation of what changes are required in EM methods. The aim is also to identify necessary methodical and technological adaptations of EM for supporting the transition of enterprises to CE.