How many inventors can be filled in the patent application?

There is no limit on the number of applicants and inventors for a patent application. The position of the first inventor is the most important, and the second and third are of certain significance. The latter is only the meaning of nominally participating in the project. The number of applicants will affect the application fee. If one person applies, the application fee will be reduced by 85%, and if two or more people apply, it will be reduced by 70%.