CPC Main Group
H04M 19/00 Current supply arrangements for telephone systems (for selecting-equipment H04Q1/28)
4 direct subcodes
Child Classifications
Navigate with arrow keys, Enter to open
- H04M 19/02 providing ringing current or supervisory tones, e.g. dialling tone or busy tone
- H04M 19/06 in which current supply sources at subordinate switching centres are charged from the main exchange
- H04M 19/08 with current supply sources at the substations (generating ringing current H04M19/04)
Top Applicants
Top 10 applicants by patent filingsfor class H04, 2013–2023, worldwide · Source: EPO PATSTAT
- HUAWEI TECHNOLOGIES COMPANY CN 101,476
- QUALCOMM US 101,139
- SAMSUNG ELECTRONICS COMPANY KR 96,655
- TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 57,744
- LG ELECTRONICS KR 55,253
- HUAWEI TECHNOLOGIES COMPANY 54,181
- SONY CORPORATION JP 35,309
- ZTE CORPORATION CN 32,950
- INTEL CORPORATION US 27,533
- GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION CN 27,498