Howdy, not sure if this is the right place to ask but I figured this community has the best chance of using libreoffice. I recently started to learn about gpg and decided to try to digitally sign an odf file I created via libreoffice writter. Thought I could do the same with a pdf file but turns out you need a third party ca certification, so now I’m wondering, assuming only open formats can be signed, why even sign an odf file in the first place? Is it just for niche situations or do official/mainstream entities now support that format? Would it be considered legally binding? I heard that microsoft office gained support for the odf format back in 2021 so if the digital signature could still be verified on their end then I don’t see a problem. Is that the case? My bad for all the questions I’m just trying to see the usecase for this seems to me that for anything professional signing with a third party ca cert. would be the better option.
I’m not sure if this is legally binding, but it’s a way to prove that someone said “I signed this document and it has not been modified.” While S/MIME certificates are most commonly used for this purpose, getting one (especially for free) is nearly impossible. Signing with a GPG key is just using another tool, one whose ecosystem doesn’t require CA-sanctioned trust; the reader decides which keys are trusted and verified.