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ISO 639-3 Change Management

Knowledge of human languages at any point in time will never be complete or perfect, but is always expanding. Given the comprehensive nature of ISO 639-3, changes to the code set are inevitable, especially in respect to lesser-known languages. An updated version of the code set will be released once each year, and all changes since the inception of the code will be reported on this page. Since the initial release of the DIS was in 2005, there have been minor changes in the forms of some language names (corrections and additions), the addition of a few code elements, and the retirement of one code element. These changes have been made to keep ISO 639-3 aligned with 639-2. With the announcement of ISO 639-3 as a published International Standard, this Registration Authority will now begin to manage the Part 3 code set as a separate entity, though always maintaining compatibility with Part 2. The following paragraphs give the guidelines that the Registration Authority has been instructed to observe in managing the change process. Instructions for submitting a change request are given elsewhere.


Care shall be taken in making changes to ensure that existing uses of the code set are not seriously compromised. To ensure continuity and stability, the identifier for any given language shall not be changed. On occasion, given compelling reasons, a code element may be retired from current use. When a code element is retired, the identifier for that code element shall not be reassigned. Retired code elements remain part of the code set and retain their identifier and denotation. Continued use in existing data or implementations remains a valid application of this standard. On-going generation of data using a retired code element is generally discouraged, however.

The names of languages listed for a given identifier may be changed given sufficient reasons without implying any change in intended denotation. Other information relating to a code element--the scope of the language, the type of language, its participation in a macrolanguage or collective grouping (aspects intended to be informative, not normative, with reference to the standard)--may also be changed, provided that such change clarifies or corrects the intended denotation, and does not confuse or alter the language denoted by the code element.

Given sufficient reasons, new code elements may be added, or the denotation for a given code element may be broadened. The denotation of a code element shall not be narrowed, however, as this can result in an unknown proportion of the existing uses of a code element becoming invalid. If it is determined that the denotation of a code element was too broad, such as if a linguistic variety that was thought to be a dialect of a given language was later determined to be a distinct language, the existing code element would be retired and replaced with two new code elements.

If a language variety thought to be a distinct language is found on further investigation to be a dialect variant encompassed by another language, the former denotation may be merged into the latter. This has the result of broadening the latter denotation. The code element for the former variety will be retired, and the relationship to the code element for the latter denotation will be documented.

Change documentation

Changes to the code set are documented in several different ways on this website. Current Change Requests are listed on the Change Request Index page (filter set to Current). Change Requests are also permanently archived and may be searched on the same Change Request Index page for proposals from prior review cycles by setting the filter to Past.

Summary reports of past series of change requests are also available:

In addition to the Change Request documentation, the history of any code element can be tracked on its detailed documentation page, which can be found through the primary code tables page for all active code elements. A separate Retired Code Elements Index lists all retired code elements with a link to a detailed documentation page giving the history for the code element. For both active and retired code elements, it is possible to link directly to the appropriate documentation page by using a URL of the pattern where "aaa" may be replaced by any valid identifier.

All changes to the code tables involving code element retirements are also documented in brief in the Retired Code Element Mappings table, with instructions on how to update existing data containing retired identifiers.