In the process of examination and approval, invention patents need to go through five stages: acceptance, preliminary examination, publication, actual examination and authorization. Generally speaking, it takes about 18 months from acceptance to publication, and about 1.5 to 2 years from actual review to authorization.
For utility model patents and design patents, the examination and approval only need to go through three stages: acceptance, preliminary examination and authorization, which is much shorter than the authorization period of invention patents, generally within 6 months.