Martyn, welcome to the forum
I don't have a definitive list, but if one were to compile one (e.g. via this thread!) one could add 'Rating Scales' to it...
As a starter, one could, if one had access to SQL, do the following:
SELECT table_name
FROM all_tab_Columns
WHERE column_name = 'BUSINESS_GROUP_ID'
AND nullable = 'Y';
You'd probably need to do a bit of weeding out on the results of that, in that it's a bit simplistic - some things only permit a null BG because they have potential to be legislative in nature, e.g. elements - I don't think you can actually set up an element yourself without the business group id being applied.
Hope this helps, and hopefully others will chip in with their own experiences
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