Patent inventors can arrange many people, and there is no limit to the maximum number. By default, according to the principle of contribution, it is the first inventor, the second inventor, the third inventor, the fourth inventor and the fifth inventor from front to back. How many individual inventors there are, it is necessary to sign several positions. However, many inventor positions are only used to prove that you have participated in patent research, which does not mean that you have reached the accreditation standard of the evaluation unit. Generally speaking, the top four patents are valid, which is a general requirement of evaluation units. As for the lower inventor position, whether it is effective or not should be determined according to the evaluation standard of the unit. There are few effective cases, and even if they are effective, the title effect is not as good as the top four.