There is no main classification number for invention patents that have passed the preliminary examination.

Several types of patents have passed the preliminary examination. Passing the preliminary examination of invention patent means that my invention patent has passed the preliminary examination without obvious substantive defects or obvious non-compliance with legal provisions. After passing the examination, substantive examination is required, and the patent can only be obtained through substantive examination. Some substantive audits can be carried out immediately, while others can only be carried out after 18 days.