Top IPC subclasses
1
|
C02F
|
4
|
Treatment of water, waste water, sewage, or sludge
|
2
|
C05F
|
3
|
organic fertilisers not covered by subclasses , , e.g. fertilisers from waste or refuse
|
3
|
A01K
|
1
|
animal husbandrycare of birds, fishes, insectsfishingrearing or breeding animals, not otherwise prov
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