Top IPC subclasses
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1
|
F24J
|
10
|
Production or use of heat not otherwise provided for
|
|
2
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C02F
|
5
|
Treatment of water, waste water, sewage, or sludge
|
|
3
|
H01L
|
4
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Semiconductor devices; electric solid state devices not otherwise provided for
|
|
4
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B04B
|
2
|
centrifuges
|
|
5
|
G08B
|
2
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signalling or calling systemsorder telegraphsalarm systems
|
|
6
|
G09B
|
2
|
educational or demonstration appliancesappliances for teaching, or communicating with, the blind, de
|
|
7
|
F24S
|
2
|
|
|
8
|
H02S
|
2
|
|
|
9
|
B01D
|
1
|
Separation
|
|
10
|
A99Z
|
1
|
subject matter not otherwise provided for in this section
|
|
11
|
H05B
|
1
|
electric heatingelectric lighting not otherwise provided for
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|
12
|
H02J
|
1
|
circuit arrangements or systems for supplying or distributing electric powersystems for storing elec
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