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CPC Main Group
H04K 1/00

Secret communication

7 direct subcodes

Child Classifications

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  • H04K 1/04 by frequency scrambling, i.e. by transposing or inverting parts of the frequency band or by inverting the whole band
  • H04K 1/06 by transmitting the information or elements thereof at unnatural speeds or in jumbled order or backwards
  • H04K 1/08 by varying the polarisation of transmitted waves
  • H04K 1/10 by using two signals transmitted simultaneously or successively

Top Applicants

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

  1. HUAWEI TECHNOLOGIES COMPANY CN 101,476
  2. QUALCOMM US 101,139
  3. SAMSUNG ELECTRONICS COMPANY KR 96,655
  4. TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 57,744
  5. LG ELECTRONICS KR 55,253
  6. HUAWEI TECHNOLOGIES COMPANY 54,181
  7. SONY CORPORATION JP 35,309
  8. ZTE CORPORATION CN 32,950
  9. INTEL CORPORATION US 27,533
  10. GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION CN 27,498