Hierarchy/Derived subclasses
| 271 / 8.1 | -> 18 | -> 42 | -> 131 | -> 132 | |
| -> 133 | -> 134 | ||||
| -> 135 | |||||
| -> 136 | |||||
| -> 137 | -> 138 | ||||
| -> 139 | -> 140 | ||||
| -> 141 | |||||
| -> 142 | |||||
| -> 143 | |||||
| -> 144 |
uspto searches
Patent Apps in 271/131Granted Patents in 271/131
Use the links above or do an advanced search in ppubs for:
(271/131.ccls. or 271/132.ccls. or 271/133.ccls. or 271/134.ccls. or 271/135.ccls. or 271/136.ccls. or 271/137.ccls. or 271/138.ccls. or 271/139.ccls. or 271/140.ccls. or 271/141.ccls. or 271/142.ccls. or 271/143.ccls. or 271/144.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.