The actual real authority is the ASN.1 specification itself but at present SC6 is the committee that has the authority to interpret what that means. No changes are anticipated since Object Identifiers are fairly simple and have been standardized with no changes for many years. By reference this URN namespace inherents those rules. By reference this URN namespace inherents those rules. There are multiple entities that assign new OIDs to the general public.
Lexical equivalence is achieved by exact string match.
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