2021.09.30 13:54 "Re: [Tiff] Adobe is in full control of the TIFF standard (email thread with Scott Foshee): FYI", by Scott Ribe

Since Adobe is the copyright holder for Adobe TIFF, you can not create a Geospatial TIFF standard that’s based on Adobe TIFF without a license from Adobe.

So they claim control of it, but refuse to do anything with it.

Unless things changed when I wasn't looking, file formats are not copyrightable, only the documents describing them. So that sentence is just a bullshit attempt at intimidation. Of course you could run into trademark issues with the word TIFF, if Adobe had a trademark registered, which they do not and apparently NEVER have had. (Yes, they could try to claim something about constructive use, but they have long since effectively abandoned any such claim...)

And it seems he's essentially claiming that they have never before reserved or documented tags based on uses developed outside Adobe, which I also think is utterly false

It's always good to start out nice, and I'm not sure you've yet reached the end of nicely pleading for help. But when they start throwing around empty legal bs and generally acting hostile, it might be time to talk to your corp attorney and think about a letter from them pointing out a couple of things, just to be prepared.

All my opinion--I tend to get riled up by companies making bogus claims about intellectual property law when they clearly should know better.

(Please note that I removed Adobe folk from the reply-all; as an outsider to this discussion I do not want to throw gasoline on the fire by challenging them in such blunt terms--just pointing this out in case it might be useful to you all.)