IPv4 deals for ISPs: transfer, lease, registry and title

The legal landscape of IPv4 trading is evolving, with significant implications for Internet Service Providers (ISPs). Over $2.3 billion worth of transfers occurred last year, despite the fact that registrars argue these addresses cannot be 'owned,' only used under shifting policies.

• A private sale does not by itself complete an IPv4 transfer: the relevant Regional Internet Registry must accept the process and update its records.
• A lease normally grants time-limited use without a permanent registry transfer; registration and any legal property claim are separate questions.

Four questions, not one “purchase”

The word “trade” hides four transactions. A transfer changes the registered holder under Regional Internet Registry (RIR) policy. A lease or service arrangement permits use for a term, often without a permanent holder change. Registration records the resource, holder and contacts in an RIR database. Ownership is a legal characterisation that depends on contract and applicable law; it does not arise automatically from a WHOIS or RDAP entity.

The distinction determines who can request a ROA, delegate reverse DNS, change abuse contacts, cooperate with the RIR or recover the block at termination. A prefix can be routed while those authorities remain misaligned. Conversely, a contract can require payment even though the registry has not accepted the transfer.

What the official policies establish

ARIN records a transfer only when the source and recipient satisfy policy. Following approval, the recipient must provide a Registration Services Agreement and applicable fees. The holder remains responsible for organisation and contact records, reassignments, reverse DNS and fees. ARIN completion should therefore be a closing condition, not a post-payment chore.

In the RIPE NCC region, a legitimate holder may transfer eligible resources and the result must be reflected in the RIPE Database. Policy allows permanent or non-permanent transfers, leaves responsibility with the original holder until completion and generally applies a 24-month lock to recently received scarce resources. An agreement marketed as a “lease” should say whether it is a registered non-permanent transfer, a sub-allocation or merely a connectivity service; those structures confer different authority.

APNIC is explicit that neither delegation nor registration confers ownership; account holders are custodians of resources licensed for use. Off-policy transfers are not recognised. For an ordinary IPv4 transfer, the source must be the registered holder, the recipient must show a use plan and Whois must reflect the result. This rejects both the claim that every address is freely saleable property and the opposite claim that economically valuable contractual rights cannot move.

Leasing trades flexibility for incomplete control

A lease can cover temporary demand, but it often leaves the provider on the registry. The ISP must state who controls RPKI ROAs, IRR objects, BGP announcements, reverse DNS, geolocation, abuse contacts and RIR evidence. The contract should also preserve continuity if the lessor loses its account, becomes insolvent, is sanctioned, stops paying fees or refuses an urgent change.

It is inaccurate to say every lease is prohibited or that every lease is a transfer. Treatment depends on resource type, RIR, registration structure and network relationship. In the RIPE region, PA space assigned with a service normally returns to the provider when service ends; it is not the customer's portable asset. A registered permanent or non-permanent transfer follows a different chain of authority.

Due diligence before signature

Resource: verify the exact prefix, RIR, PA/PI or legacy status, holder, downstream assignments, holding periods and disputes. Parties: verify legal existence, signatory authority, restructurings, insolvency, relevant security interests and sanctions. Registry status is important operational evidence, but it is not by itself a title opinion in every jurisdiction.

Closing: tie final payment to RIR approval and agreed record changes. Escrow must address failure, delay and refunds. Seller warranties should cover authority, no double commitment, accurate data and cooperation through completion without promising that an RIR or every third-party network will accept the outcome.

Routeability: inspect BGP history, hijacks, reputation lists, reverse DNS, IRR objects, ROAs, geolocation filters and more-specific announcements. A Whois update does not compel every operator to accept a route or erase damaged reputation.

Control after closing

An operable file includes the agreement, RIR decision, before-and-after records, route authorities, ROAs and IRR objects, administrative access, abuse contacts, DNS delegations and a return or renumbering plan. A lease also needs change deadlines, incident support, an orderly exit and a ban on simultaneous reuse.

Policies change, and inter-RIR transfers apply requirements from both regions. An ISP should confirm the current version directly with the registries before commitment and obtain legal advice in the relevant jurisdictions. The decisive issue is not the wording on an invoice but whether contract, registry and technical controls align.