What is the ratio of patent application fee to R&D investment?

10%。 The ratio of patent application fee to R&D investment shows that the ratio of patent application fee to R&D investment is 10%, and patent literally means exclusive rights. The word "patent" comes from Latin, which means open letters or open documents. It is a certificate used by medieval monarchs to issue certain privileges, and later refers to the exclusive rights certificate signed by the British king himself.