Is OAuth2 Authorization header with "Bearer [access_token]" standard?

Question

Question regarding the OAuth2 Authorization header,

Some sites use Authorization: Bearer [access_token]

but some sites use Authorization: OAuth [access_token].

So is both of them a valid oauth2 spec based on https://www.rfc-editor.org/rfc/rfc6750 ?

Answer 1

Authorization: Bearer [access_token] is defined in RFC 6750, but Authorization: OAuth [access_token] is not.

You can find Authorization: OAuth ... in RFC 5849 (The OAuth 1.0 Protocol). Note that RFC 5849 is obsoleted.