Smallest Transfer and Transfer Types
The smallest block that can be transferred is a /24 (256 IPv4 addresses) except in the RIPE NCC service region. They do not have a minimum size on a transfer. But blocks smaller than a /24 won’t be usable on the internet – though they could be used on private and semi-private networks.
RIRs have two types of transfer policy. One covers transfers within their own region, an intra-RIR or in-region transfer. The other covers transfers between regions, and inter-RIR transfer.
AFRINIC does not have a policy for inter-RIR transfers, so its members cannot sell into or buy from other regions.
RIPE policy explicitly supports temporary transfers, also called leases. These transfers revert back to the original holder at the conclusion of the agreed term. Leasing is possible in ARIN and LACNIC, too. But LACNIC leases can only be for addresses issued before it was created. APNIC policy does not allow leasing and all the pre-APNIC IPv4 addresses are subject to APNIC policy.