It depends on the policies of the RIR (Regional Internet Registry) in the region where the IPs are from.
That said, if you're willing to ignore the RIR's policies (which a lot of people do) you can usually "black market" trade IP addresses, so long as you can convince your upstreams to accept them (which they usually will).
Comments
It depends on the policies of the RIR (Regional Internet Registry) in the region where the IPs are from.
That said, if you're willing to ignore the RIR's policies (which a lot of people do) you can usually "black market" trade IP addresses, so long as you can convince your upstreams to accept them (which they usually will).
Many of the legacy allocations were made before RIRs existed, so no policies really apply.
Sure, but when you want to update the WHOIS / reverse DNS or whatever you have to convince an RIR. If you don't care then I guess that's fine.