Simple Registration extension

OpenID Simple Registation is an extension to the OpenID Authentication protocol that allows for the retrieval of eight commonly requested pieces of information when an End User signs in with an OpenID identifier to a supporting site.

This extension uses the OpenID Authentication request as its transport and allows -- assuming permission is granted by the user -- the retrieval of a user's nickname, email address, full name, date of birth, gender, postcode, language and timezone. Applications can specify that each field is either required or optional, though of course the user can always elect not to use the site if he or she considers the required fields to be unacceptable.

For more detail, see the Simple Registration specification.