Reason: According to Article 69 of the Patent Law, "a patented product or a product directly obtained by a patented method, after being sold by the patentee or a unit or individual licensed by it, uses, promises to sell, sells or imports the product" is not regarded as infringement of the patent right.
At the same time, in practice, the patentee (i.e., the enterprise) agrees to the buyer's use of its patent for production by paying a reasonable consideration to purchase the patented product.