Found 2 records.

Status: Held for Document Update (2)

RFC 3709, "Internet X.509 Public Key Infrastructure: Logotypes in X.509 Certificates", February 2004

Note: This RFC has been obsoleted by RFC 9399

Note: This RFC has been updated by RFC 6170

Errata ID: 2679
Status: Held for Document Update
Type: Technical
Publication Format(s) : TEXT
Reported By: Alexey Melnikov
Date Reported: 2010-12-22
Held for Document Update by: Sean Turner

Section 4.1 says:

LogotypeDetails ::= SEQUENCE {
   mediaType       IA5String, -- MIME media type name and optional
                              -- parameters
   logotypeHash    SEQUENCE SIZE (1..MAX) OF HashAlgAndValue,
   logotypeURI     SEQUENCE SIZE (1..MAX) OF IA5String }

Notes:

The mediaType is underspecified, as no specific syntax is given.
E.g. are spaces allowed before parameters? Also, my understanding is that IA5String disallows UTF-8, while media type parameters can possibly include UTF-8 values.

I would recommend referencing ABNF from Section 4.2 of RFC 4288.

Errata ID: 2325
Status: Held for Document Update
Type: Editorial
Publication Format(s) : TEXT
Reported By: Alexey Melnikov
Date Reported: 2010-07-13
Held for Document Update by: Tim Polk

Section 4.1 says:

   When using indirect addressing, the URI (refStructURI) pointing to
   the external data structure MUST point to a binary file containing
   the DER encoded data with the syntax LogotypeData.  The referenced
   file name SHOULD include a file extension of "LTD".

Notes:

There is no IETF process for only registering a file extension. IETF MIME type registry allows to register MIME types together with the corresponding file extensions. An update to this document should register a new MIME type for "LTD".

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