CPC Subgroup
A61K 31/56 Compounds containing cyclopenta[a]hydrophenanthrene ring systems; Derivatives thereof, e.g. steroids
Full Title
Medicinal preparations containing organic active ingredients > Compounds containing cyclopenta[a]hydrophenanthrene ring systems; Derivatives thereof, e.g. steroids
Filing statistics
CPC A61K 31/56 belongs to the parent subclass A61K, which recorded 1,717,491 patent applications worldwide between 2013 and 2023. Annual filings grew from 114,681 in 2013 to 125,843 in 2023 (+10%), peaking at 182,901 applications in 2016. The most active applicants in class A61 are PHILIPS ELECTRONICS (20,621 applications), NOVARTIS (15,792 applications) and ROCHE (14,303 applications).
Source: EPO PATSTAT, worldwide filings
4 direct subcodes
Child Classifications
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- A61K 31/565 not substituted in position 17 beta by a carbon atom, e.g. estrane, estradiol
- A61K 31/57 substituted in position 17 beta by a chain of two carbon atoms, e.g. pregnane or progesterone
- A61K 31/575 substituted in position 17 beta by a chain of three or more carbon atoms, e.g. cholane, cholestane, ergosterol, sitosterol
- A61K 31/58 containing heterocyclic rings, e.g. danazol, stanozolol, pancuronium or digitogenin (digitoxin )
Top Applicants
Top 10 applicants by patent filingsfor 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