Most of my knowledge about this is from my interaction with them as a member of a non-profit organisation which has benefited from a couple of specific ones.
In Sweden we have a term called "Stiftelse" it's close to a trust but i dont know enough about trusts to really compare, from a legal standpoint a "Stiftelse" owns it self and all money in care of it may only be transfered/used according to the legal document drafted at its creation.
Also every "Stiftelse" is under supervision of the state.
Some are exempt from tax though I'm not clear on what is required to be exempt.
My knowledge of the specific type of "Stiftelse" that our endeavour would be is very limited as its not the type i have had interactions with.
There should be similar things elsewhere (as the concept of a trust or trust-like organisation is an old one). Is there something like this in France? Seems like a logical place (for us) to have such a thing if it exists.
Could this be something worth looking into? (obviously I think so

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