scope:

Purpose and Scope

This recommended practice defines metadata indicators to be used to indicate free-to-read content and a link to license terms for the use/re-use of that content. Humans and machines will be able to assess the status of the content based on these indicators and in many cases the combination of the free_to_read and license_reference metadata will indicate Open Access content. The indicators include a date component so that content with access and re-use rights that change over time can be adequately understood by both humans and machines using the metadata.