Chondroitin sulphate API (Active Pharmaceutical Ingredient) is produced by various manufacturers worldwide. Here's an overview of some prominent companies that make chondroitin sulphate API:

　　Pharmaceutical Companies in China: China is a major producer of chondroitin sulphate API. Several pharmaceutical companies in China, including Shandong Yibao Biologics Co., Ltd., Jiaxing Hengjie Biopharmaceutical Co., Ltd., and Qingdao WanTuMing Biological Products Co., Ltd., are known for manufacturing chondroitin sulphate API.

　　It is important to note that the availability of specific manufacturers may vary, and new companies may emerge in the market over time. For the most accurate and up-to-date information on chondroitin sulphate API manufacturers, consulting with pharmaceutical suppliers and industry databases is recommended.