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Stages in the ISO Process

The UTC and ISO/IEC JTC1/SC2 (the subcommittee responsible for the maintenance of ISO/IEC 10646) synchronize the character repertoire and code points of their respective standards: characters are not added to one standard without being approved for the other. While proposed characters may have been approved by either committee, they only become part of the Unicode Standard when a version containing them is published.

Due to the nature of its membership, the Unicode Consortium has designed its process to be responsive to market requirements. The ISO standards review and approval process is by nature lengthier than the Unicode process, involving, as it does, national standards organizations of any country wishing to participate. In that process, a proposal goes through the following stages before publication. The numbers for these stages are cited in the ISO Stage column on the Proposed New Characters (Pipeline Table) page. "WG2" refers to Working Group 2, the working group under SC2 which handles the technical work on ISO/IEC 10646.

  1. Initial Proposal: A proposal document has been submitted to WG2 and is included in the formal document record. The proposal may not yet have been taken up on the agenda of a WG2 meeting, or may have had been included pro forma on an agenda, where it is simply raised FYI to the attention of national bodies, inviting them to review and provide feedback on the proposal.
  2. Provisional acceptance by WG2: A proposal has been technically reviewed by WG2, with feedback from one or more national bodies and liaison organizations such as the Unicode Consortium, and a consensus has been reached within WG2 that a character, group of characters, or a repertoire for a script should be encoded. However, a final resolution specifying code positions and character names may not yet have been taken or approval may be postponed pending further feedback from national bodies regarding one or more technical issues in the proposal. (In recent times, this stage has seldom been used by WG2.)
  3. Final acceptance by WG2 - in Bucket: WG2 has decided to specify code positions and character names for addition to the standard, but without necessarily determining which amendment they should be included in for formal balloting. This status is referred to as "being in the bucket," a holding category waiting for an appropriate amendment. This stage is transitional and typically is only used when WG2 has a meeting that does not authorize a formal amendment to 10646.
  4. Hold for Committee Ballot: WG2 has decided to specify exactly which of any characters approved and "in the bucket" are to be balloted in an amendment to 10646. Note that in current practice, most character approvals move directly from Stage 1 to Stage 4, for efficiency, unless there is some technical issue with them or unless WG2 decides that it needs to wait before starting to progress a new amendment.
  5. Committee Ballot: This stage comprises one or more formal committee ballots by the member bodies of the WG2 parent committee, SC2. During each ballot, member bodies and liaison organizations (such as the Unicode Consortium) review the collection of characters and scripts in the ballot document and provide technical and editorial feedback. After each ballot is completed, the editor resolves the comments. This stage can take a year to two years, depending on the schedule of ballots and of WG2 meetings. Technical changes to the approved characters may still occur as part of this process, including the addition of characters that were not originally on the ballot. This stage begins as soon as the SC2 Secretariat has issued the formal amendment ballot. In this ballot phase the committee draft is known as a PDAM (Proposed Draft Amendment) or CD (Committee Draft). After resolution of PDAM or CD ballot comments by the editor, WG2 may decide to issue an additional committee ballot, or if the ballot seems mature, move on to the next ballot stage.
  6. Enquiry Ballot: SC2 has submitted the DAM (Draft Amendment) or DIS (Draft International Standard) for approval by the national bodies at the SC2 level. During this stage, there may still be technical changes to the ballot text, although every effort is made to resolve technical issues during the committee ballot(s), before an enquiry ballot is issued. This is a five month ballot.
  7. Approval Ballot: SC2 has submitted the FDAM (Final Draft Amendment) or FDIS (Final Draft International Standard) for approval by the national bodies at the JTC1 level. At this stage, which is largely pro forma, there are no further technical changes to the ballot text. This is a two month ballot. The issuance of the FDAM ballot is the point at which Unicode implementers can feel secure in implementing the corresponding, synchronized repertoire in the Unicode Standard. When the FDAM ballot is approved, JTC1 considers the amendment fully approved, awaiting publication.
  8. ITTF Publication: An approved amendment to 10646 is submitted to ITTF for formal publication. An amendment to a standard (or the standard itself) is not actually considered an International Standard until ITTF has completed publication. Depending on the complexity of the standard and any editing issues which may turn up, this may take several months to more than a year from the completion of the FDAM ballot.

Note: Sometimes final ISO approval of new characters can occur a long time after they have been approved by the UTC. Conversely, in some instances a character or group of characters may reach Stage 4 or even Stage 5 or Stage 6 in the ISO process before they have been formally considered for approval by the UTC. During the period when the ISO process is not complete and when the UTC may still be in the process of synchronizing character approvals, use of proposed characters is at an implementer's own risk. The repertoire and allocation of the characters may change before they are published in a particular version of the Unicode Standard.