Legal analysis: The protection period of an invention patent starts from the date of application.
Legal basis: "Patent Law of the People's Republic of China"
Article 28 The date when the patent administration department of the State Council receives the patent application documents is the filing date. If the application documents are mailed, the postmark date shall be the date of application.
Article 42 The term of invention patent rights is twenty years, and the term of utility model patent rights and design patent rights is ten years, both calculated from the date of application.