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IPC Main Group
H04M 7/00

Arrangements for interconnection between switching centres

Introduced: September 1968

Last revised: January 2006

Classification Context

Section:
ELECTRICITY
Class:
ELECTRIC COMMUNICATION TECHNIQUE
Subclass:
TELEPHONIC COMMUNICATION

Filing statistics

IPC H04M 7/00 belongs to the parent subclass H04M, which recorded 292,116 patent applications worldwide between 2013 and 2023. Annual filings declined from 26,112 in 2013 to 15,773 in 2023 (-40%), peaking at 34,745 applications in 2017. The most active applicants in class H04 are QUALCOMM (97,396 applications), HUAWEI TECHNOLOGIES COMPANY (96,502 applications) and SAMSUNG ELECTRONICS COMPANY (86,981 applications).

Source: EPO PATSTAT, worldwide filings

8 direct subcodes

Child Classifications

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  • H04M 7/02 for compensating differences of ground potential
  • H04M 7/04 for compensating differences of line impedance
  • H04M 7/06 using auxiliary connections for control or supervision
  • H04M 7/08 for phantom working
  • H04M 7/1 for two-way working, i.e. calls may be set-up in either direction over the same connection
  • H04M 7/12 for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal
  • H04M 7/14 in systems involving main and subordinate switching centres
  • H04M 7/16 in systems employing carrier frequencies

Top Applicants

Top 10 applicants by patent filingsfor class H04, 2013–2023, worldwide · Source: EPO PATSTAT

  1. QUALCOMM US 97,396
  2. HUAWEI TECHNOLOGIES COMPANY CN 96,502
  3. SAMSUNG ELECTRONICS COMPANY KR 86,981
  4. TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 55,869
  5. HUAWEI TECHNOLOGIES COMPANY 55,349
  6. LG ELECTRONICS KR 53,649
  7. CANON 33,341
  8. SONY CORPORATION JP 32,761
  9. ZTE CORPORATION CN 32,274
  10. GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION 28,327