Derwent believes that the selection criteria for the input of structural information into the Derwent Chemistry Resource are of great importance. In response to customer comments we have developed an updated set of DCR guidelines to better meet customer requirements. These guidelines are summarised below.

• Cover all claimed compounds.
• Cover at least the main (best) example. If there are few claimed compounds, more examples will be selected.
• For compounds outside the claims, only real compounds (i.e. those with good supporting physical or biological data) will be selected.
• Where compounds are selected from a range of examples, those which best illustrate the structural diversity of patent coverage will be selected.

New DCR-specific quality checks support these guidelines, to enable Derwent to continue providing high quality indexing.