2021.09.30 00:43 "Re: [Tiff] Proposal to create a OGC BigTIFF standard", by Leonard Rosenthol
As noted, Adobe owns the core TIFF specification and the tag registry. We (Chris Cox, at the time) was also part of the community that defined the modifications necessary for “BigTIFF”, and although I was a member of the list at the time, I was not an active party. I need to see if I can track down any internal information (and/or reach out the Chris) to find out what agreements Adobe may have made with the community at the time for the ownership of these extensions as that most certainly impacts any standardization by another organization.
I do know that we (Adobe) have worked with other groups such as various ISO committees to standardize SUBSETS of TIFF for particular workflows and it may well be that BigTIFF could also fall into that – but there are lots of details that would need to be worked out.