In the United States, serial number/application sequence number is used to distinguish patent types and different application years: XX/XXXXXX, with the first two XX indicating application types, 0 1-28 for invention and plant patent applications, 29 for design patent applications, 60 for temporary patent applications, 90 for unilateral reexamination requests and 95 for bilateral reexamination requests, for example, 08/1.
In Japan, the application number format = type+application+year+serial number of the current year, for example, the invention application is a special application. . . . The utility model relates to a wish. . . . Appearance is will. . . . (It may mean application)
The European patent number has not been studied. Appearance seems to be applied separately, not in the category of "patent", but in industrial design.