DWPI Chemistry Indexing

CPI Chemical Indexing

Derwent CPI Chemical Indexing (also known as Fragmentation Coding) is a system of alphanumeric coding that indexes information about specific and general (aka Markush) chemical substances disclosed in patent documents and associated concepts like pharmaceutical activities, properties, and more. It covers patent documents in areas of pharmaceutical, agrochemical, and general chemical technology beginning in the 1960s and continues to this day. Previous to the introduction of the Derwent Chemistry Resource (DCR) in 1999 and Derwent Markush Resource (DWPIM) in 1987, it was the only method to conduct searches based on chemical structure in the Derwent World Patents Index.

Access to CPI indexing is available in the WPIDS and WPIX files on STN and requires a Chemical Patents Index (CPI) subscription. Contact your Derwent representative for questions about CPI subscriptions or to request training.


CPI Chemical Indexing Guides

The CPI Chemical Indexing Guide contains detailed descriptions of how documents are indexed, how to search using the coding system, and definitions of all the codes. A chart showing the main Sections of CPI Fragmentation Codes is available here: CPI Fragmentation Codes Chart.

Note that the Section P codes are incomplete in the above chart, as from DWPI Update 2015/01 the Section P Fragmentation Codes, covering pharmaceutical and agrochemical activity, have been revised and enhanced.

A complete list of Section P Codes including the 2015 revisions can be found in the above CPI Chemical Indexing User Guide.  A chart showing the revised Section P Fragmentation Codes is available here: Section P Fragmentation Codes Chart 2015.

A chart showing the Section R Fragmentation codes, which cover pharmaceutical formulations, is available here: Section R Fragmentation Codes Chart 2015


CPI Manual Codes

The CPI Manual Codes index the novel features of chemistry-related patents, and are useful for subject searching and patent analysis.

See here for further details and links to the latest version of the CPI Manual Codes Manual. CPI Manual Codes are searchable via Derwent Innovation, STN, ProQuest Dialog and Questel.  A CPI subscription is required to access this content



Derwent Chemistry Resource on STN

The Derwent Chemistry Resource (DCR) is a chemical structure database of specific compounds indexed in Derwent World Patents Index. Searchable on STN by structure and text, this user guide gives comprehensive details of the search and display fields, along with worked examples.



Derwent Markush Resource on STN

Markush structures are captured as part of the editorial process for DWPI, and are searchable in the Derwent Markush Resource file on STN (file DWPIM).  This user guide  provides full details on query construction, database searching, and results handling in both DWPIM and DWPI files on STN.  For subscription details, please contact your local STN representative.