The subject of this paper focuses mainly on the world car industry and, especially, on how to implement Internet of Things (IoT) technology into the Japanese, German, and U.S. car industries, as well as on differences between the concepts of IoT usability in those target countries. The car industry is now at a difficult phase with regard to how to adjust secret information for car production using openaccess IoT technology. Intercorporate relationships provide advantages for car production in general; however, this openaccess IoT technology is likely to completely re-arrange these relationships. It will be very interesting to see how these
relationships will re-arrange. In this paper, we apply the "smiling curve concept" to find a solution for differences in IoT usability in the target countries. Then, we assess producer's ideas, such as the smart factory in Germany and Japan, and the user's need for a smart car in the U.S.A. As a result, we explain the advantages of intercorporate relationships and how integral parts of the product will be replaced using IoT technology.