DIFF Subgroup
A61K 31/56 Compounds containing cyclopenta[a]hydrophenanthrene ring systems; Derivatives thereof, e.g. steroids
Introduced: July 1974
Full Title
Medicinal preparations containing organic active ingredients > Compounds containing cyclopenta[a]hydrophenanthrene ring systems; Derivatives thereof, e.g. steroids
IPC and CPC are identically structured here. All 4 subcodes exist in both systems.
2 shared codes have differing titles between IPC and CPC.
IPC defines codes here since 1974.
Child Classifications
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- A61K 31/565 not substituted in position 17 beta by a carbon atom, e.g. estrane, estradiol since 1974 IPC+CPC Available in IPC and CPC
- A61K 31/57 substituted in position 17 beta by a chain of two carbon atoms, e.g. pregnane or progesterone since 1974 IPC+CPC Available in IPC and CPC
- A61K 31/575 substituted in position 17 beta by a chain of three or more carbon atoms, e.g. cholane, cholestane, ergosterol, sitosterol since 1974 IPC+CPC Available in IPC and CPC
- A61K 31/58 containing heterocyclic rings, e.g. danazol, stanozolol, pancuronium or digitogenin (digitoxin ) since 1974 IPC+CPC Available in IPC and CPC
Top Applicants
Top Applicants (IPC)
Class A61,2013–2023, worldwide · Source: EPO PATSTAT
- PHILIPS ELECTRONICS NL 18,523
- NOVARTIS CH 14,253
- COVIDIEN US 13,953
- ROCHE CH 12,005
- CHINESE ACADEMY OF SCIENCES 11,955
- UNIVERSITY OF CALIFORNIA US 11,692
- HARVARD UNIVERSITY US 11,596
- L'OREAL FR 11,593
- P&G (PROCTER & GAMBLE COMPANY) US 11,297
- OLYMPUS CORPORATION JP 9,594
Top Applicants (CPC)
Class A61,2013–2023, worldwide · Source: EPO PATSTAT
- PHILIPS ELECTRONICS NL 20,621
- NOVARTIS CH 15,792
- ROCHE CH 14,303
- COVIDIEN US 13,862
- HARVARD UNIVERSITY US 13,454
- UNIVERSITY OF CALIFORNIA US 12,798
- P&G (PROCTER & GAMBLE COMPANY) US 12,140
- L'OREAL FR 11,800
- OLYMPUS CORPORATION JP 9,894
- BOSTON SCIENTIFIC SCIMED US 9,513