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 Summary Sheet


Producer:Chemical Abstracts Service (CAS), USA
Coverage:1907 - present plus over 180,000 pre-1907 records
File Size:Over 39.2 million records (09/2017)
File Type:Bibliographic
Content:Biochemistry, chemistry, and chemical engineering

The HCA File is a bibliographic database covering international journals, patents, patent families, technical reports, books, conference proceedings, and dissertations from all areas of chemistry, biochemistry, chemical engineering, and related sciences from 1907 to the present. CA also includes over 110,000 records for patents and journal articles dated before 1907.

Records contain bibliographic information, substance and subject indexing, including CAS Registry Numbers, and abstracts. Cited references are included for journals, conference proceedings, and basic patents from the US, EPO, WIPO, and German patent offices added to the CAS databases from 1997 to the present. Beginning in 2003, patent examiner citations from British and French basic patents are also included. Beginning in 2005, patent examiner citations from Canadian patents have been included.

HCA contains thesauri for records from 1967 to the present in the Controlled Term (/CT) field for the CA Lexicon, in the Role (/RL) field for the CAS Roles, in the Company Name (/CO) field for company names, in the International Patent Classifications (/IPC) field for pre-IPC Reform and Reform IPCs, and in the National Patent Classification fields. In addition, a thesaurus is also available for CA Sections for records from 1907 to the present as well as for the records dated before 1907.

CAplus is a more current and more comprehensive file than CA. CAplus contains all the records included in CA plus records for recent publications that have not yet been fully indexed. In addition, CAplus contains records for all articles from nearly 1,500 key chemical journals since October 1994, including records for document types not covered in CA, such as letters to the editor or news announcements. CAplus is updated daily with new bibliographic records and weekly with indexing information.

Three pricing options are available:

  • low connect-hour with search-term charges
  • connect-hour with no search-term charges (HCAplus file)
  • no connect-hour charge with higher search-term charges (ZCAplus file).


Chemical Abstracts Service
2540 Olentangy River Road
P. O. Box 3012
Columbus, Ohio 43210-0012
Phone: (+1) 614-447-3700
Telefax: (+1) 614-447-3751
Email: help(at)cas(dot)org

Usage Terms

The CAS Information Use Policies which apply to your use of the HCA File on STN are explained in detail.

Contents of CAS Information Use Policies

Part 1:
I. Introduction
II. Definitions

Part 2:
III. Authorized Use of CAS Information

Part 3:
IV. Unauthorized Use of CAS Information
V. Special Permission
VI. Further Information

Further details on the STN Information Keep & Share Program.