Who decides if file format is popular enough to have its own MIME type

file formatmime-types

Who decides, if a program is popular enough to have its own MIME type?

Right now, I program something for dealing with .srt subtitles – and while on wikipedia, it has application/x-subrip MIME type, nothing like that is seen in the official IANA MIME list.

How is that determined? Who decides, if srt is popular enough to have its own listing in IANA MIME list?

Best Answer

  • If you follow a few links from that IANA (MIME) Media Types page, you'll find RFC 4288, which describes the process. There are at least four "trees":

    • Standards
    • Vendor
    • Personal/Vanity
    • Experimental

    Your question is about the standards tree:

    Registrations in the standards tree MUST be approved by the IESG and MUST correspond to a formal publication by a recognized standards body.

    • A "recognized standards body" drafts a proposal
    • It is also announced on an official mailing list
    • Interested parties discuss it
    • The IESG approves it (or not)
    • An appointed "media types reviewer" makes sure the proposal meets all detail requirements
    • It is published by IANA

    So to answer your question, a standards body must first decide it is "popular enough" to pursue, and then the Internet Engineering Steering Group (a part of the IETF, Internet Engineering Task Force) must agree.