I already read this page. It does not address my question. My interrogation is around the fact that mixing several dictionaries in the same page is considered a derivate product or not. Intuitively it is, so I don’t understand how this does not break the ND clause of some source material. So they must be some non obvious legal loophole I want to know about, or this website is breaching some licences.
It's a fair question. The Ministry of Education's interpretation for its use of ND clause scopes specifically to the individual items, not the compilation:
"The use of words, radicals, strokes, glyphs, phonetic readings and interpretations of the individual items in the Revised Mandarin Dictionary may not be modified or converted into simplified forms.
However, the change of the code according to the contents of the reference table provided by the Ministry of Education, as well as modifications unrelated to the specific items in the Revised Mandarin Dictionary specified above, are deemed as outside the scope of prohibition of modification."
Thank you very much for your reply and for the source link. This is indeed different from my previous understanding, which was based mostly on English/French CC explanations website.
I'm surprised but pleased by the clause concerning the transformation in simplified characters, and all in all this is less restrictive than what I thought.