Can anyone suggest a good way to get a CIDR block from the
internic? We are two separate isps with separate ASNs, merged under one
with one of them currently getting addresses from an upstream provider
(/20). The problem is that in that location we are out of addresses, are
multi-homed, and
dissatisfied with our current provider. We need addresses before we can
switch over, but the internic refuses to release any to us until we have
used another /20 from our current provider. Thus, the internic has
forced us to use one carrier with poor service. Legally, is this a
monopoly? Has anyone started a class action suit? Can anyone help us?

Get new IP's from your new provider. Renumber fast. Change your DNS TTL
very low. Maybe have your new provider hold primary DNS in the meantime.