The following principles must be fulfilled before a standard can be included on the list. The standard must be:
- - Fully documented and publicly available;
- - Freely implementable without economical, political or legal limitations on implementation and use;
- - Approved by an internationally recognized standards organisation such as ISO, and standardized and maintained in an open forum through an open process;
- - It must be demonstrable that the standard can be directly implemented by anyone in its entirety on multiple platforms;
- - Interoperable within the functionality parameters with the other standards on the list
Take special note of the last point — what is interesting is that initially, ODF is the only standard on the list, so what this means is that even if OOXML should make the cut, it must "play well" with ODF.
There is an additional provision that documents that are not intended for editing must be published in PDF/A-1 format.
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