On behalf of the International Organization for Standardization (ISO) and in support of ISO 32000, Adobe maintains this registry of the prefixes of second class names for PDF. It is freely open to all developers and organizations following the specifications given in Annex E of ISO 32000.
Create a new Issue, filling out the template to register the prefix you want to reserve. Assuming that the name has not been used already, it will be added to the publicly available XLSX file and you will receive an email confirmation. If there is a conflict, you will be notified and can select an alternative.
If you wish to register multiple prefixes for your organization, please create one issue per prefix.
Create a new Issue, filling out the template with the updated information. Please add any instructions, such as instructing Adobe to make a previously private registration public, add that in the Additional Instructions section.
The XLSX file in this repository contains all developer prefixes that have been registered since 2008 (when ISO 32000-1 was published). This document is maintained by the registrars and no PRs to change it will be accepted.
NOTE: Due to legal reasons, Adobe maintains the list of all registrations that occured prior to that 2008.