People sought an
allocation from IANA originally, but that does not give IANA nor
any contact listed by IANA "ownership" or "management" authority
over usage of this IP address space outside of their registry which
is supposed to accurately cover the internet: but the AMPRnet is Not
a block of networks on the internet, and not under the purview
of IETF or IANA, anyways --- its just a community that uses
TCP/IP mostly in isolated discrete networks which can be neither
allocated, nor managed, nor get their individual assignments
within 44/8 from any central authority.
Yes and no.
There were actually a number of “class As” that Postel directed to be assigned based on layer 2 technology, e.g., 14/8 for X.25, 24/8 (I believe) for IP over CATV, 44/8 for IP over amateur radio, maybe a block assigned for IP over satellite (4/8? I don’t remember). In some cases, there was a ‘caretaker’ assigned (ARRL for 44/8 and @Home for 24/8) who acted as a pseudo-registry: they did (or at least were supposed to do) sub-assignments for entities that met (IANA- and pseudo-registry-) defined criteria. However, the informal assignments were, like all assignments of the day, based on the assumption that the addresses were supposed to be used to provide IP networking and if the addresses weren’t so used, they were to be returned to IANA. This was actually put in practice with 14/8 (which unfortunately didn’t have a ‘caretaker’ so we at IANA had to try to track down the remaining IP over X.25 users starting around 2007 or so IIRC — a bit challenging, but ultimately accomplished). I have vague memories of asking Brian Kantor (as the assignee in the IANA registry) about returning 44/8 back when we were cleaning up 14/8 but my recollection was that I was informed it would be too hard given the number, distribution, and global nature of the sub-assignments.
In any event, this is largely irrelevant: there weren’t any contracts or other written agreements, it was all informal and based on folks doing the right thing, without fully agreed upon terms of what the “right thing” was (other than “for the good of the Internet” I suppose).