Hierarchy/Derived subclasses
254 / 2r | -> 4r | -> 4b |
-> 4c |
uspto searches
Patent Apps in 254/4rGranted Patents in 254/4r
Use the links above or do an advanced search in ppubs for:
(254/4r.ccls. or 254/4b.ccls. or 254/4c.ccls.)
This will show what classes derive from the input. Ex: entering 43/42.24 shows the derived classes and the search that can be used to find patents or patent applications in those subclasses.