How Many Electronic Databases Have More Than 10000 CAS Numbers?

31 Aug

I have been invited to write an article regarding Open Access Chemistry Databases and am in the process of gathering information. During one of my google searches I happened across a statement I was aware of but had forgotten until recently. It relates to the ability to use CAS numbers on a website. Specifically, from the CAS Information Use Policies of 2005 it says, quote:

“A User or Organization may include, without a license and without paying a fee, up to 10,000 CAS Registry Numbers or CASRNs in a catalog, website, or other product for which there is no charge. The following attribution should be referenced or appear with the use of each CASRN: CAS Registry Number® is a Registered Trademark of the American Chemical Society. CAS recommends the verification of the CASRNs through CAS Client ServicesSM.”

I interpret this as meaning that above 10,000 CAS numbers permission must be granted to the organization gathering togethering a data collection. Based on my experience there are a LOT of situations where collections of more than 10,000 CAS numbers exist. We are presently deduplicating and indexing another million structures on the ChemSpider index. We regularly receive SDF files (are these electronic “catalogs”?) containing structures and CAS numbers…and when these contain over 10,000 CAS numbers are they inadvertently going against CAS policy? Are all of those online databases with a large number of structures doing so with permission (for example ChemIDPlus, ZINC DB, eMolecules and, of course, PubChem.

I can only imagine if these large collections/websites/databases do not have permission to expose over 10,000 CAS numbers. What a public relations nightmare that could open up! Since we deposited the PubChem dataset to ChemSpider that naturally includes any associated registry numbers. Since eMolecules has deposited portions (not all) of the PubChem dataset they also have deposited the registry numbers.

I may be lighting a fire here, and might get some interesting calls as a result, but I am publicly asking the question…if you are managing a website or public data collection of over 10,000 CAS numbers (read that as any site exposing PubChem data) have you asked permission to expose the data? And … did you get permission? CAS numbers are everywhere…they are “phone numbers” for chemistry. On cans and boxes in our kitchen and garage. On webpages all over the place. This is a very interesting situation for “large chemistry databases”…


About tony

Antony (Tony) J. Williams received his BSc in 1985 from the University of Liverpool (UK) and PhD in 1988 from the University of London (UK). His PhD research interests were in studying the effects of high pressure on molecular motions within lubricant related systems using Nuclear Magnetic Resonance. He moved to Ottawa, Canada to work for the National Research Council performing fundamental research on the electron paramagnetic resonance of radicals trapped in single crystals. Following his postdoctoral position he became the NMR Facility Manager for Ottawa University. Tony joined the Eastman Kodak Company in Rochester, New York as their NMR Technology Leader. He led the laboratory to develop quality control across multiple spectroscopy labs and helped establish walk-up laboratories providing NMR, LC-MS and other forms of spectroscopy to hundreds of chemists across multiple sites. This included the delivery of spectroscopic data to the desktop, automated processing and his initial interests in computer-assisted structure elucidation (CASE) systems. He also worked with a team to develop the worlds’ first web-based LIMS system, WIMS, capable of allowing chemical structure searching and spectral display. With his developing cheminformatic skills and passion for data management he left corporate America to join a small start-up company working out of Toronto, Canada. He joined ACD/Labs as their NMR Product Manager and various roles, including Chief Science Officer, during his 10 years with the company. His responsibilities included managing over 50 products at one time prior to developing a product management team, managing sales, marketing, technical support and technical services. ACD/Labs was one of Canada’s Fast 50 Tech Companies, and Forbes Fast 500 companies in 2001. His primary passions during his tenure with ACD/Labs was the continued adoption of web-based technologies and developing automated structure verification and elucidation platforms. While at ACD/Labs he suggested the possibility of developing a public resource for chemists attempting to integrate internet available chemical data. He finally pursued this vision with some close friends as a hobby project in the evenings and the result was the ChemSpider database ( Even while running out of a basement on hand built servers the website developed a large community following that eventually culminated in the acquisition of the website by the Royal Society of Chemistry (RSC) based in Cambridge, United Kingdom. Tony joined the organization, together with some of the other ChemSpider team, and became their Vice President of Strategic Development. At RSC he continued to develop cheminformatics tools, specifically ChemSpider, and was the technical lead for the chemistry aspects of the Open PHACTS project (, a project focused on the delivery of open data, open source and open systems to support the pharmaceutical sciences. He was also the technical lead for the UK National Chemical Database Service ( and the RSC lead for the PharmaSea project ( attempting to identify novel natural products from the ocean. He left RSC in 2015 to become a Computational Chemist in the National Center of Computational Toxicology at the Environmental Protection Agency where he is bringing his skills to bear working with a team on the delivery of a new software architecture for the management and delivery of data, algorithms and visualization tools. The “Chemistry Dashboard” was released on April 1st, no fooling, at, and provides access to over 700,000 chemicals, experimental and predicted properties and a developing link network to support the environmental sciences. Tony remains passionate about computer-assisted structure elucidation and verification approaches and continues to publish in this area. He is also passionate about teaching scientists to benefit from the developing array of social networking tools for scientists and is known as the ChemConnector on the networks. Over the years he has had adjunct roles at a number of institutions and presently enjoys working with scientists at both UNC Chapel Hill and NC State University. He is widely published with over 200 papers and book chapters and was the recipient of the Jim Gray Award for eScience in 2012. In 2016 he was awarded the North Carolina ACS Distinguished Speaker Award.
Leave a comment

Posted by on August 31, 2007 in ChemSpider Chemistry


0 Responses to How Many Electronic Databases Have More Than 10000 CAS Numbers?

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.