Hierarchy/Derived subclasses
| 220 / 4.01 | -> 4.04 | -> 4.08 | -> 4.09 | -> 4.11 |
uspto searches
Patent Apps in 220/4.09Granted Patents in 220/4.09
Use the links above or do an advanced search in ppubs for:
(220/4.09.ccls. or 220/4.11.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.