Chemical Abstracts Service

Chemical Abstracts Service (CAS) was founded in 1907 with offices initially at the National Bureau of Standards in Washington, D.C. CAS settled in Columbus in 1909. CAS provides pathways to published research in the world's journal and patent literature -- virtually everything relevant to chemistry plus a wealth of information in the life sciences and a wide range of other scientific disciplines back to the beginning of the 20th century.


CAS, a division of the American Chemical Society, is the world's leader in providing scientists online and web access to chemistry-related research data. CAS produces the world's largest and most comprehensive databases of chemical information and makes them available through sophisticated search and analysis software for the use of scientists engaged in new product and patent research, as well as academic research in the world's leading universities. CAS databases include more than 23 million abstracts of chemistry-related literature and patents and more than 26 million organic and inorganic substances and over 56 million sequences. Click here for the latest count.

CAS was founded in 1907 with the aim of monitoring, abstracting, and indexing the world's chemistry-related literature. This aim was first accomplished through the well known printed reference work CHEMICAL ABSTRACTS (CA), which CAS continues to publish after more than 90 years. CAS began to develop computer-based publication technologies in the 1960s in order to automate the publication of CA. Today, CAS editorial processes apply the best advantages of document analysis by highly trained scientists and the benefits of advanced information technology.

CAS indexes and abstracts patents, articles from approximately 9,000 scientific journals, conference proceedings, and other documents pertinent to chemistry, life sciences and many other fields. In 2004 alone, CAS scientists provided

  • abstracts and indexing for over 865,000 journal articles, patents, and other research materials
  • CAS Registry Numbers and substance records for more than 17 million substances.

Through the printed CA, CA on CD™, the STN Internationalsm online network, the CAS files distributed through licensed vendors, the
SciFinder® and SciFinder Scholar™  desktop research tools, and the STN Easy® or STN on the Web servicessm, data produced by CAS is accessible to virtually any scientific researcher worldwide in industry, governmental research institutions, and academia. (CAS/STN product information)

Substance identification is a special strength of CAS, which is widely known for the CAS Chemical Registry, the largest substance identification system in existence. When a chemical substance is newly encountered in the literature processed by CAS, its molecular structure diagram, systematic chemical name, molecular formula, and other identifying information are added to the Registry and assigned a unique CAS Registry Number®.

CAS Registry Numbers are used in reference works, databases, and regulatory compliance documents by many organizations around the world to identify substances without the ambiguity of chemical nomenclature.