provided by
provided by FIZ Karlsruhe

New on STN

December 2019

CAplus (SM) Now Provides Non-Conventional Patent Families for Chinese Dual Filings

November 2019

PatentPak(R) now available in USPATFULL/USPAT2 on STNext(R)

November 2019


This website uses cookies. Matomo is used for the usage analysis. By continuing to use the website, you agree to this. If you object to the usage analysis or would like to learn more about cookies, please click on the privacy policy. Close

CAS REGISTRY chemical nomenclature enhanced

30. December 2006

Chemical nomenclature in REGISTRY has been enhanced with more logical and consistent CA Index Names. This enhancement represents the most significant modification to chemical nomenclature in REGISTRY since the introduction of the 9th Collective Index (9CI) nomenclature in 1972.

Newly registered substances are now assigned a CA Index Name based on the updated chemical nomenclature. Previously registered substance names will be converted to the new CA Index Names beginning in 2007.

Updates to chemical substance name displays include:

  • The CA Index Name in the Chemical Name (CN) field is now displayed without CI labels.
  • The CA Index Name of previously registered substances will be replaced by the new CA Index Name. The CN of previous CA Index Names will appear under Other CA Index Names and will continue to display CI labels.
  • If the CA Index Name of a previously registered substance is identical to the new CA Index Name, the CI label will no longer be displayed.

The chemical nomenclature enhancement may impact search strategies in SDIs or in saved search queries. Users are encouraged to confirm the validity of these queries.

Additional information on the nomenclature enhancement is available at:

The revised REGISTRY Database Summary Sheet is available in STNGuide and on the WEB on our Database List.