According to official website of Beijing Tongrentang, Imperial Palace is a brand owned by Beijing Tongrentang and produced by Luannan Branch of Beijing Tongrentang Xing 'an Health Care Technology Co., Ltd. Beijing Tongrentang is a well-known Chinese medicine enterprise with a long history and rich experience. The products used in the Forbidden City have undergone strict quality control and research and development, and meet the relevant national standards and requirements. Therefore, the Forbidden City is not an OEM, but a brand product produced by a subsidiary of Beijing Tongrentang.