Version 4 ICC Specification
Version 4 of the ICC profile specification was first published in 2001. The v4 profile format has introduced a number of changes when compared to the previous v2 specification. These changes provide a number of advantages, the most significant of which follow from the removal of ambiguities from the specification and a more precise definition of the PCS. More information about the advantages of the V4 specification can be found here.
These lead to an improved predictability of performance of a profile in use which will lead to a reduction of major differences of interpretation. Therefore, when pairs of profiles are used they should always produce the same result - regardless of which CMM is used. A summary of reasons to use the v4 specification is available.
As color management requirements evolve, the profile specification undergoes a process of continuous review by members of the ICC. The current version is ICC.1:2022-05 (Version 22.214.171.124) and is available on the ICC Specification page.
The specification has also been approved as an ISO standard (ISO 15076-1).
Almost all platforms and color management applications support ICC V4. You can test whether your system is V4-compatible here.