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DIFF Subgroup
A61K 31/395

having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins

Introduced: July 1974

Full Title

Medicinal preparations containing organic active ingredients > Heterocyclic compounds > having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins

Of 11 combined children, 10 exist in both systems.

1 codes are CPC-only extensions.

5 shared codes have differing titles between IPC and CPC.

IPC defines codes here since 1974.

Child Classifications

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  • A61K 31/396 having three-membered rings, e.g. aziridine since 2000 IPC+CPC Available in IPC and CPC
  • A61K 31/397 having four-membered rings, e.g. azetidine since 2000 IPC+CPC Available in IPC and CPC
  • A61K 31/53 having six-membered rings with three nitrogens as the only ring hetero atoms, e.g. chlorazanil, melamine (melarsoprol A61K31/555 ) since 1974 IPC+CPC Available in IPC and CPC
  • A61K 31/5545 CPC only CPC only

Top Applicants

Top Applicants (IPC)

Class A61,2013–2023, worldwide · Source: EPO PATSTAT

  1. PHILIPS ELECTRONICS NL 18,523
  2. NOVARTIS CH 14,253
  3. COVIDIEN US 13,953
  4. ROCHE CH 12,005
  5. CHINESE ACADEMY OF SCIENCES 11,955
  6. UNIVERSITY OF CALIFORNIA US 11,692
  7. HARVARD UNIVERSITY US 11,596
  8. L'OREAL FR 11,593
  9. P&G (PROCTER & GAMBLE COMPANY) US 11,297
  10. OLYMPUS CORPORATION JP 9,594

Top Applicants (CPC)

Class A61,2013–2023, worldwide · Source: EPO PATSTAT

  1. PHILIPS ELECTRONICS NL 20,621
  2. NOVARTIS CH 15,792
  3. ROCHE CH 14,303
  4. COVIDIEN US 13,862
  5. HARVARD UNIVERSITY US 13,454
  6. UNIVERSITY OF CALIFORNIA US 12,798
  7. P&G (PROCTER & GAMBLE COMPANY) US 12,140
  8. L'OREAL FR 11,800
  9. OLYMPUS CORPORATION JP 9,894
  10. BOSTON SCIENTIFIC SCIMED US 9,513