The Electronic Product Code Information System (EPCIS) is a state of the art information system for tracking and monitoring the lifecycle of physical objects based on RFID technology. Low-cost passive RFID tags are replacing traditional barcodes for physical object identification and are heavily used within logistics and trade. They are an essential aspect of identifying physical objects, therefore an integration into the IoT is required. This paper presents a concept, which defines how the EPCIS can be integrated into the IoT extending it to a so called Smart Thing Information System (STIS). The integration follows a two-fold approach. On the one side, the information of the EPCIS is made available for IoT devices and services, by providing a lightweight query interface. On the other side, the information of non-RFID related devices, such as sensors and actuators of home and building automation systems (BAS) are made available to EPCIS. Thus, a seamless integration with building automation systems is possible. The extended system embraces interoperability by resting upon standards such as OBIX and CoAP. We present a case study using a globally testbed that demonstrates the feasibility of the proposed system extension. In addition, a performance analysis is carried out that investigates the scalability impacts and limits of the STIS new interfaces as well as the gateway for BAS.