ARIN and the economics of post-exhaustion legitimacy

Field	Value
Author	BTW Research
Published	2026-07-01
Primary category	arin
Categories	governance; rir-watchdog; arin
SEO title	ARIN and the economics of post-exhaustion legitimacy
SEO description	A research analysis of why ARIN's post-exhaustion role requires a legitimacy theory built around scarcity, transfer governance, member power, legacy-resource certainty, and registry accountability rather than allocation-era assumptions.
Focus keyword	ARIN post-exhaustion legitimacy
Primary domain	Governance
Content type	Research
Topic	post-exhaustion legitimacy
Subject	ARIN
Region	North America
Time horizon	12-24 months
Impact	HIGH
Confidence	B / 0.88

The institution after the well runs dry

The easiest way to misunderstand ARIN is to treat it as the same institution after IPv4 exhaustion that it was before exhaustion. The initials are the same. The corporate form is still a not-for-profit membership body. The staff still run a registry. The board, advisory structures, public policy process and service-region vocabulary still exist. Public documents still speak of community-developed policy and stewardship of Internet number resources. Yet the political economy beneath these continuities has changed. A registry with a free IPv4 pool is a rationing institution. A registry after depletion is a title, transfer and trust institution. Its legitimacy no longer rests mainly on whether it can distribute scarce-but-available addresses fairly. It rests on whether it can maintain a credible record of control over resources that have become operational capital, while avoiding two opposite failures: becoming a passive clerk for private bargains or becoming a gatekeeper that stretches technical authority into economic control.

ARIN is the most revealing case because North America sits at the meeting point of three unusually strong pressures. The first is the weight of legacy IPv4 holdings in a region that dominated the early commercial, academic and governmental Internet. The second is a mature secondary market in which IPv4 blocks are treated by buyers, sellers, brokers, lawyers, lenders and bankruptcy estates as valuable transferable assets, even though registry policy stops short of recognising ordinary freehold property in addresses. The third is a membership structure in which the actors most capable of sustained institutional participation may also be the actors with the largest operational or financial stake in how scarcity is governed. That does not make ARIN corrupt, captured or illegitimate. It makes ARIN a hard case for a larger proposition: the allocation-era theory of registry legitimacy is no longer enough.

The allocation-era theory was elegant because it fitted the economic conditions of its time. There was a central stock of unallocated IPv4 addresses. Demand was growing. The registry's task was to conserve a finite resource, distribute it according to documented need, preserve uniqueness and prevent waste from becoming a routing problem for everyone else. Legitimacy came from open participation, neutral procedure, needs-based criteria and a claim of stewardship over a shared technical resource. Those principles were never frictionless, but they matched a world in which a disappointed applicant could imagine returning with better documentation, a smaller request or a clearer deployment plan. Exhaustion ended that comfort. Once the free pool ran dry, the institution no longer mediated mainly between applicants and a replenishable public stock. It mediated between incumbents and entrants, registered certainty and private bargains, market liquidity and routing discipline, legal expectations and policy discretion.

That shift is why ARIN should now be analysed less as a dispenser of numbers and more as a constitutional body for a scarce digital resource. The analogy has limits. IP addresses are not land. The registry does not create the underlying protocol. Routes work because networks choose to recognise and propagate them. Yet an IPv4 block has become a financial and operational claim around which companies plan, insure, buy, sell, borrow, merge and litigate. In such a setting legitimacy is not a decorative virtue. It is a production input. If counterparties believe the registry will recognise transfers predictably, the market can price risk. If operators believe registry records are accurate, routing-security services can gain adoption. If legacy holders fear that policy may retroactively unsettle their standing, they will resist formalisation. If new entrants believe incumbents can shape scarcity rules for their own advantage, the registry's claim to community authority thins.

ARIN's public materials are useful exhibits for this analysis, but they are not the analysis itself. They describe the service region, the categories of transfer, membership rules, election arrangements, legacy-resource services, the Number Resource Policy Manual and the relation between resources, agreements and services such as RPKI and IRR. Those documents reveal institutional machinery. They do not settle the more important question: what makes that machinery legitimate when the registry is no longer primarily allocating new IPv4 space? A post-exhaustion institution cannot answer that question by pointing to its inheritance. It has to explain why inherited forms still deserve confidence under changed economic conditions.

The old bargain: conservation, need and equal procedural standing

The modern registry system was a response to the defects of informality. Early IPv4 distribution reflected the experimental and academic origins of the network. Large blocks were handed out when the cost of generosity seemed small and the future scale of the Internet was poorly understood. Classful addressing created enormous units and crude distinctions. A Class A block contained more than sixteen million addresses. A Class B block contained more than sixty-five thousand. Those categories were technically convenient but economically blunt. They left some early holders with more address space than later commercial networks could hope to obtain under mature conservation rules.

The regional registry model brought a more disciplined political economy. ARIN, established in 1997, joined RIPE NCC, APNIC, and later LACNIC and AFRINIC in a system that divided number-resource administration by service region. The legitimacy claim was that a not-for-profit body close to affected operators would apply transparent policies, verify need, record assignments accurately and preserve uniqueness. The system did not require everyone to agree that addresses were a public commons in some philosophical sense. It required enough confidence that a regional registry would be better than a scramble for numbers, better than unilateral claims and better than central administration too far removed from operational reality.

Needs-based allocation was the practical expression of that bargain. A network seeking addresses had to show that earlier holdings were being used efficiently and that new space would serve an operational purpose. Conservation and routability worked together. If blocks were too large and too loosely distributed, depletion would accelerate. If blocks were too small and too scattered, routing tables could fragment. The registry could therefore claim legitimacy by balancing an applicant's demand against the interest of the Internet community as a whole. Scarcity existed, but it was not yet absolute. The argument was about how to slow depletion and allocate fairly before depletion arrived.

That bargain also made member power look comparatively benign. The same operators who depended on number resources had the field knowledge needed to write workable policy. A registry run without network operators would lack practical understanding of renumbering, customer assignments, abuse contacts, multihoming, route aggregation and deployment timing. A registry run only by states would invite geopolitical bargaining and slower technical adaptation. A registry run only by staff would lack consent from those whose routing and assignment practices made the number system meaningful. Community process was not mere ceremony. It was the institutional technology that reconciled private operational knowledge with a shared technical resource.

Every element of that bargain changes shape after exhaustion. When addresses remain available, a policy dispute is partly a dispute over access to future distribution. When addresses are exhausted, a policy dispute increasingly concerns the value, mobility and certainty of existing holdings. Under allocation, incumbency is mostly historical fact. Under exhaustion, incumbency is a market position. Under allocation, strict need rules restrain waste. Under exhaustion, strict need rules also affect who can buy, how quickly sellers can monetise unused space and how much friction brokers and advisers must price into a deal. Under allocation, a refusal to issue a larger block is an administrative denial. Under exhaustion, a refusal to recognise a transfer can derail a private transaction involving a scarce asset.

This is the hinge of ARIN's legitimacy problem. Procedural continuity is necessary, but not sufficient. The substance of decisions has changed. The distributional effects have changed. The incentives of participants have changed. The cost of institutional error has changed. A delay or policy change can alter market value. A data-quality failure can affect financing, routing security, merger diligence and abuse response. A governance structure that looked adequate for operational consultation may look thinner when it effectively sets rules for a secondary market worth billions of dollars in aggregate.

Exhaustion as an economic regime change

IPv4 exhaustion was not an unexpected meteor strike. The finite size of a 32-bit address field was always known. Conservation mechanisms, private addressing, network address translation, classless routing and eventually IPv6 all existed because the system understood that the original supply was limited. In February 2011 the central IANA free pool was depleted when the last blocks were distributed to the regional registries under global policy. ARIN's own free pool reached zero on 24 September 2015. The date matters not because it produced a single dramatic rupture, but because it made North America's registry economics unavoidably post-allocation.

The depletion of a free pool does not mean the resource disappears. It means the old price signal disappears. Before exhaustion, the explicit fee paid to a registry was not a market price for an address. It was a service and membership charge inside a needs-based allocation system. Scarcity was rationed administratively. After exhaustion, a network requiring IPv4 space must obtain it from a holder, a transfer market, a merger or acquisition, a lease or quasi-lease, address-sharing technology, operational redesign or a combination of these. A market price emerges not because the registry declares addresses to be property, but because the registry can no longer satisfy demand by ordinary issuance.

That difference is crucial. Official institutions often prefer to emphasise IPv6 as the long-term answer, and technically they are right. IPv6 is the only scalable escape from the 32-bit constraint. But a correct engineering destination is not a complete account of the transition economy. IPv4 remains embedded in access networks, cloud platforms, enterprise systems, hosting, security tools, customer expectations and interconnection arrangements. Dual stack, carrier-grade NAT, IPv4-as-a-service and translation systems are not marginal footnotes. They are costly adaptations to a long period in which IPv4 still carries commercial necessity even as new free allocations are unavailable. The registry's legitimacy is judged in this messy interval, not in the clean endpoint imagined by transition rhetoric.

The transfer market is the visible expression of the interval. A transfer is not merely a database update. It is a transaction in which a seller's unused or underused block becomes a buyer's continuity plan, expansion tool or strategic hedge. The registry verifies that the source is the current registered holder, that the resources are not subject to unresolved dispute, that the recipient qualifies under policy, that relevant agreements are in place and that the record changes in a way the wider Internet can rely on. ARIN's transfer architecture distinguishes merger, acquisition and reorganisation transfers, specified-recipient transfers inside the region and inter-regional transfers with compatible policy requirements. The categories are administrative on the surface; economically they define the channels through which scarce control can move.

This machinery creates a new institutional tension. The registry cannot be a mere notary, because inaccurate or abusive transfers would pollute the record and raise routing, fraud and dispute risk. Yet it cannot behave like an allocation-era planner with the same degree of discretion, because the resource being transferred is already held, priced and relied upon. The post-exhaustion registry must be more like a ledger with public-interest guardrails than a gatekeeper of first distribution. Its legitimacy depends on getting that distinction right.

A serious ledger is not passive. It verifies identity, authority, chain of control, status and finality. It resists forged signatures and confused corporate histories. It records enough information for third parties to rely on the result. It has correction procedures. It treats like cases alike. It is transparent about requirements. But it does not invent scarcity, allocate political favour or use procedural leverage to pursue unrelated institutional goals. When ARIN requires agreements, minimum transfer sizes, source verification or evidence of operational use, it acts as a public-interest ledger with conditions. When conditions seem to extend beyond registry necessity or to reflect incumbent preferences, the institution risks becoming an economic gatekeeper without the legitimacy theory that would justify such power.

Why North America is the hard case

ARIN's region is not simply one geography among five. It is the region where the early Internet left unusually large legacy-resource questions. North America housed many of the earliest universities, research institutions, technology companies, defence contractors, network vendors and commercial Internet operators. The result is a stock of legacy address blocks that predate ARIN's ordinary contractual framework. Research on IPv4 scarcity has long noted that a large share of legacy address space sits in the ARIN-administered environment, reflecting North America's early dominance in address assignment. That fact is not an accusation. It is a structural condition.

Legacy resources create a special legitimacy problem because they sit between history and modern policy. A legacy holder may not have received its block under the same expectations as a contemporary ARIN customer. It may have relied for decades on public registration of that block. It may not accept that later policy can alter its standing as easily as policy governs a new allocation. At the same time, the wider Internet depends on accurate registry data, secure routing services and predictable transfer treatment. The public cannot simply say that legacy blocks are private islands beyond the registry's concern. Nor can the registry simply say that history no longer matters.

ARIN's treatment of legacy holders illustrates the compromise. Legacy holders not under an ARIN agreement can maintain Whois and RDAP registration data, manage reverse DNS delegations, maintain registry records through ARIN Online and use DNSSEC-related services. Access to RPKI and IRR services, however, requires resources to be under an ARIN agreement. The Legacy Registration Services Agreement, offered from 2007 through the end of 2023 for legacy resources in the service region, created a path into a clearer contractual relationship. The legacy fee cap expired on 31 December 2023, with continuing limits for certain resources covered before 1 January 2024 and ordinary Registration Service Plan fees applying for legacy resources covered after that date.

Those details show why the issue is institutional rather than merely administrative. RPKI has become more important as networks try to reduce route hijacking and improve origin validation. If legacy holders remain outside agreements because they fear costs or loss of autonomy, routing-security adoption may suffer. If ARIN makes agreement too costly or legally heavy, it may push precisely the holders it needs toward minimal engagement. If it makes agreement too light, it may weaken the accountability and fee fairness expected by ordinary customers. Legacy policy is not a dusty historical corner. It is a present-day test of how a registry earns consent from holders whose economic position is partly outside the allocation-era bargain.

North America also has a dense commercial environment for IPv4 transactions. Cloud platforms, hosting companies, access networks, content networks, security providers, managed service firms and enterprises with complex merger histories all have practical reasons to acquire or transfer IPv4 space. IPv6 deployment may be rational in the long run, but the near-term cost of losing IPv4 reachability is not theoretical. Customers still expect services to work over IPv4. Business-to-business systems still carry IPv4 dependencies. Acquisition diligence still asks whether number resources can move with assets. Bankruptcy estates still ask whether address holdings can be monetised for creditors.

The legal and corporate environment reinforces the point. North American bankruptcy, merger, asset-sale and financing practices are accustomed to converting operational assets into recoverable value. If a distressed company holds IPv4 space, advisers will ask whether the space can be sold. If a buyer acquires a business line, it will ask whether the addresses used by that network can move. If a block is tied to a disputed corporate chain, the registry may become the practical arbiter of whether the deal can close. The more valuable IPv4 becomes, the more ARIN's operational decisions resemble market infrastructure.

That is why ARIN cannot rely only on the moral capital of the old stewardship story. The old story says: we conserve and allocate a shared resource in the community interest. The new North American story must say more: we maintain a reliable ledger for scarce digital resources; we protect routing and registration integrity; we respect historical reliance; we constrain transfer-market abuse; we keep policy power accountable to those affected by scarcity; and we distinguish legitimate verification from discretionary control over private economic value.

Member power after scarcity

Membership-based governance is one of the registry system's strongest and weakest features. It is strong because number-resource policy is technical and operational. The people who run networks know what bad policy does. They understand renumbering costs, customer assignments, route aggregation, abuse contacts, multi-homing, address planning, transfer diligence and security operations. A staff-only institution would be vulnerable to technocratic insulation. A state-led institution would be vulnerable to politicisation. An open community with elected structures gives the registry a claim that it is governed by those who bear the consequences.

It is weak because scarcity changes who has the time, incentive and resources to participate. ARIN states that interest in Internet number-resource management, not membership alone, can bring a person or organisation into the wider community, and that one need not be a member to apply for resources or participate in policy discussion. That openness matters. But voting power is narrower. ARIN's membership structure distinguishes Service Members, General Members and Trustee Members. Only General Members in good standing vote in elections through a designated voting contact. General Members must maintain participation; after the 2023 election and each election thereafter, those that do not cast a ballot in any of the previous three ARIN elections revert to Service Member status, though a blank ballot still counts as participation.

Those rules may improve electoral seriousness, but they sharpen a legitimacy question. Who votes in a post-exhaustion registry, and whose economic interests are represented by sustained participation? A small cloud company needing a /24, a large legacy holder with unused space, a broker advising transfer parties, a cable operator with millions of customers, a university with historical allocations, a security firm dependent on accurate records and an IPv6-first entrant may all care about ARIN. They do not all want the same thing. Some prefer lower transfer friction. Some prefer need checks to deter speculation. Some care most about fees. Some care about RPKI. Some care about preserving historical autonomy. Some care about avoiding rules that leave entrants dependent on expensive market purchases.

The problem is not that members vote their interests. All governance contains interests. The problem is whether the institution can distinguish legitimate operational expertise from scarcity rents. In the allocation era, an operator arguing for a policy could plausibly be seen as contributing practical knowledge to a common task. In the post-exhaustion era, the same operator may also be defending an asset or a balance-sheet option. Transfer restrictions can reduce liquidity and protect incumbents. Looser transfers can benefit sellers and brokers while exposing the registry to speculation and fragmentation. Higher legacy fees can look like modernisation or extraction. RPKI access tied to agreement can look like responsible accountability or leverage. The same rule may have both technical and distributive effects.

ARIN's answer cannot be to exclude interested parties. That would drain the institution of expertise and consent. Nor can it pretend that the old community model automatically solves post-exhaustion conflicts. A more convincing answer would make interests legible. Policy arguments based on registry integrity should be separated from arguments based mainly on private cost. Transfer outcomes, approval times, denial categories, dispute patterns and market effects should be reported in ways that respect confidentiality but illuminate institutional performance. Smaller holders, entrants, Caribbean and North Atlantic networks, public-interest users and security-dependent third parties need meaningful channels into deliberation. Voter participation should be treated not merely as an election metric, but as evidence about whether scarcity governance has consent beyond the best organised incumbents.

Member power is therefore not a side issue. The registry after exhaustion governs the conditions under which private parties can convert historical allocations into monetisable resources and under which new networks can buy their way into IPv4 continuity. That is not ordinary club administration. It is a form of market constitution. The board and advisory bodies may operate through familiar structures, but the economic stakes have moved.

Transfers and the price of certainty

ARIN's transfer rules are often discussed as compliance details. They are more than that. They are the architecture of North America's IPv4 market. Under ARIN's public transfer guide, address and ASN transfers are governed by policy. Mergers, acquisitions and reorganisations are treated under one path. Specified-recipient transfers within the ARIN region are treated under another. Inter-regional transfers require compatible, reciprocal, needs-based policies with the other regional registry. Recipient requirements include a registration services agreement unless one is already on file, operational network use, a minimum IPv4 transfer size and documentation of projected use for larger blocks. Prior utilisation and alternative utilisation criteria shape how much an organisation may receive.

These rules perform several economic functions at once. They reduce title uncertainty by requiring the source to be the registered holder. They reduce fraud risk by requiring officer acknowledgement and documentation. They preserve a link between addresses and operational networks. They limit pure paper trading by imposing need and use criteria. They reduce transaction costs by defining categories. They create comparability because parties can price the same policy constraints into negotiations. They also impose friction. A seller cannot transact with any buyer on any terms and assume the registry will record the result. A buyer cannot assume cash alone is enough. Approval time and uncertainty become part of the price.

The legitimacy question is whether that friction is justified by registry integrity or whether it preserves allocation-era control beyond its rationale. Needs-based transfer policy is the hardest case. In a world with a free pool, need is a conservation device. In a world with a private seller and buyer, need becomes a filter on who can participate in the market and how much they can acquire. It may deter speculative hoarding and maintain the link between address space and operational networks. It may also force buyers into artificial forecasts, slow legitimate deals or disadvantage entrants whose demand does not fit inherited documentation categories. A registry that keeps need checks after depletion has to explain them not as habit but as a response to identifiable harms.

There are good reasons for some need discipline. IPv4 addresses are globally unique routing resources, not entries on a private spreadsheet. A wave of purely speculative transfers could move space away from operational networks, encourage fragmentation and weaken the connection between registry data and actual use. Because routing has shared externalities, one party's private gain from slicing and reselling blocks can impose costs on many routers and operators. That gives ARIN a public-interest basis to resist a fully financialised market.

The counterargument also has force. An overly restrictive transfer regime can trap unused space with incumbents, raise prices for entrants and prolong inefficient holdings. A dark legacy block does not help the Internet merely because it is not being speculated upon. If the registry wants addresses to move from low-value to high-value use, market liquidity is not the enemy. Its task is to make liquidity truthful, secure and operationally meaningful. Excessive gatekeeping can produce the grey behaviour it seeks to prevent, as parties look for leases, shells or contractual workarounds that move economic control while formal registration lags behind reality.

The price of certainty is therefore the central market variable. Buyers pay not only for addresses but for confidence that the registry will record their control and that networks will treat the record as credible. Sellers receive value not only because IPv4 is scarce but because the registry recognises a path to transfer. Brokers earn fees partly by navigating institutional uncertainty. If ARIN improves predictability, it lowers transaction costs and may reduce the premium paid for insider knowledge. If it becomes unpredictable, it increases rents for insiders and punishes smaller participants. A legitimate registry should prefer boring predictability to discretionary drama.

Scarcity rents and the incentives they create

The allocation-era registry was designed partly to prevent waste. The post-exhaustion registry must also manage scarcity rents. A scarcity rent arises when the value of holding a resource exceeds the cost of maintaining it because supply is constrained. IPv4 blocks now carry such rents. The rent may be realised through sale, lease, avoided purchase, bargaining power in a merger or simple strategic optionality. An organisation with excess IPv4 holds something that new entrants may have to pay dearly to obtain. Registry policy affecting transferability affects that rent.

Institutional discomfort with the word "rent" is understandable. Treating IPv4 as a financial asset seems to weaken the old stewardship principle that addresses are allocated for use rather than owned. Yet refusing to name the rent does not make it disappear. It makes policy less honest. If transfer restrictions reduce liquidity, they may preserve rents for incumbents. If restrictions are loosened, they may let incumbents monetise more easily. If fees rise, the registry may capture some of the economic surplus. If agreement is required for valuable services, the registry increases its influence over holders. If need checks limit buyers, prices and availability shift.

A legitimate registry does not have to eliminate rents. It cannot. Scarcity creates them. The question is whether rents distort governance. The risk is clearest when those who gain most from a rule are also best positioned to attend meetings, sustain advocacy and vote. The appearance of capture can damage legitimacy even without bad faith. ARIN should therefore treat scarcity-rent analysis as normal policy work. Who benefits if a rule stays? Who benefits if it changes? Does the rule improve registry integrity, or does it mainly alter bargaining power? Does it help entrants, or merely make speculation easier? Does it burden legacy holders in proportion to public benefit, or does it tax history because history has become valuable?

The same analysis applies to brokers and facilitators. ARIN's public material recognises a Qualified Facilitator Program as an optional resource for customers seeking to connect with approved facilitators. Facilitation can professionalise the market, reduce mistakes and help parties understand requirements. It can also create an insider ecology around complexity. If the process is too hard for ordinary participants, specialists benefit. That is not an argument against specialists. It is an argument for making the baseline process as clear as possible and for watching whether complexity itself becomes a private rent.

Scarcity-rent analysis also explains why legacy certainty matters. A clean legacy block commands more value than a messy one. Formal agreement, accurate records and security services can increase certainty and therefore value. That is useful if it moves space to better use and improves routing trust. It is problematic if the cost of achieving certainty is unpredictable or if the institution appears to use its role to capture part of the value. The line is fine. ARIN needs to walk it openly.

The worst equilibrium would be a market that is expensive, opaque and morally denied. In such a market, incumbents enjoy value while public language insists that addresses are not property; buyers pay market prices while policy treats them as applicants; brokers profit from complexity while the registry claims neutral administration; legacy holders resist agreement while the public needs their data to be secure. A better equilibrium would be candid. IPv4 scarcity has created economic value. The registry does not need to call addresses ordinary property to recognise that transfers move valuable operational control. Its job is to make that movement accountable, secure and fair.

Legacy certainty as public infrastructure

Legacy-resource certainty is sometimes framed as a conflict between old holders and modern accountability. That is too crude. Certainty for legacy resources is public infrastructure. If the holder of a legacy block is unclear, if contact data are stale, if transfer standing is contested or if agreement status is ambiguous, the cost is not borne only by that holder. It is borne by networks trying to validate routing, buyers conducting diligence, security teams investigating abuse, courts identifying assets and users affected by hijacks or misattribution. The registry record is a shared reference point.

Certainty cannot be produced by proclamation. A legacy holder that distrusts ARIN will not become more legible simply because ARIN says agreement is good for the community. The holder must believe that entering a clearer relationship will not expose it to unpredictable fees, retroactive conditions or loss of practical control. At the same time, ARIN cannot give every legacy holder a permanent exemption from the costs and responsibilities of registry maintenance. The institution must finance accurate records, security services, support, legal review and technical operations. Other customers will not accept a system in which legacy holders enjoy valuable services indefinitely without comparable responsibility.

The retirement of the legacy fee cap after 2023 sits directly in this tension. A fee cap can be understood as a confidence-building concession: it reduces fear that signing an agreement opens the door to unpredictable future charges. Retiring it for new coverage after 1 January 2024 can be understood as fee normalisation: legacy resources use modern services and should fit modern cost structures. Both readings can be true. The legitimacy test is whether ARIN can show that the transition is predictable, proportionate and connected to actual registry costs rather than to the market value of IPv4 addresses. If fees appear to track scarcity rents, legacy holders will see extraction. If fees appear to track service costs and accountability, more holders may accept formalisation.

RPKI intensifies the issue. In the allocation era, a registry record mattered because it showed who held a block. In the routing-security era, the registry's relationship to the holder may affect whether cryptographic assertions about route origin can be made. If important legacy space remains outside RPKI because holders avoid agreements, the public benefit of routing security is reduced. Yet compelling agreement through security access can look coercive if terms are perceived as heavy. The legitimate path is narrow: ARIN must make the agreement reasonable enough that RPKI adoption looks like a mutually beneficial upgrade, not a tollbooth.

Legacy certainty also shapes market quality. A buyer prefers a block with clean registration, clear chain of control, current contacts, no unresolved disputes and predictable agreement status. A seller with such a block receives a better price. A market with more clean blocks has lower diligence costs. The registry benefits because transfers are less likely to produce litigation or record confusion. In that sense, ARIN's work with legacy holders is not merely an accommodation to historical privilege. It is an investment in market integrity.

The public-interest frame matters because it changes the tone of debate. Legacy holders should not be caricatured as hoarders merely because they hold old space. Some are universities, research bodies, enterprises and networks with complex histories and legitimate reliance. Nor should they be romanticised as sovereign owners immune from modern responsibilities. The address system works because unique numbers are publicly coordinated. A mature legitimacy theory must hold both propositions at once: historical reliance deserves respect, and registry certainty deserves support.

Accountability when procedure becomes market power

Accountability before exhaustion largely meant fair process, published policy, operational competence and accurate records. After exhaustion it also means accountability for market power. ARIN does not set private IPv4 prices, but it controls recognition. It does not decide which provider expands, but its transfer approvals affect how expansion is supplied. It does not run bankruptcy courts, but its record may determine whether an estate can sell a valuable asset cleanly. It does not own legacy space in the ordinary sense, but its agreements and services influence whether that space becomes more secure and liquid.

This sort of accountability requires evidence, not just meetings. The community should be able to see how long transfer reviews take, how often requests fail, what documentation problems recur, how many resources move within the region and across regions, how wait-list restrictions affect behaviour and whether policy changes alter transaction patterns. ARIN already publishes transfer statistics, and that is essential. But the legitimacy bar rises with market sophistication. Aggregate counts are less useful than analysis that helps the public understand institutional performance while protecting confidentiality. Delay is not neutral when prices move. Ambiguity is not neutral when small buyers cannot afford specialised advice. Denial patterns are not neutral if they fall disproportionately on certain kinds of networks.

Accountability also requires humility about institutional incentives. A registry funded by fees has incentives to preserve relevance as IPv4 allocation declines. A membership body has incentives to satisfy organised members. Staff have incentives to avoid legal risk, which may produce conservative interpretation. Incumbents have incentives to protect existing holdings. Entrants have incentives to loosen access. Security advocates have incentives to push agreement and RPKI adoption. Brokers have incentives to preserve some complexity, though they also benefit from market volume. None of these incentives is inherently improper. All of them should be visible in policy design.

The post-exhaustion registry needs a legitimacy theory that admits these incentives rather than hiding them behind a general appeal to community. Community is real, but it is not homogeneous. The same discussion can include a public-spirited engineer, a seller's adviser, a buyer's employee, a lawyer protecting a legacy client, a security operator and a network that wants lower fees. A consensus among such actors may still be legitimate, but its legitimacy depends on process design, disclosure norms, empirical grounding and the ability of less organised affected parties to be heard.

ARIN's board and advisory structures therefore carry a heavier burden than formal continuity suggests. The board's fiscal and strategic decisions affect whether the registry behaves like a service body or a scarcity regulator. The Advisory Council's handling of policy proposals affects whether transfer rules evolve with evidence or ossify around inherited assumptions. Election participation affects whether governance is sustained by a broad base or a small set of repeat actors. Legitimacy is cumulative. It is built through many low-drama decisions that tell the market, legacy holders, small networks and security-dependent users what kind of registry ARIN intends to be.

One practical implication is that ARIN should avoid the appearance of using technical services as bargaining chips. If a service is necessary for registry integrity, the case for requiring agreement should be made in those terms and priced accordingly. If a fee is necessary for cost recovery, it should be explained through cost and fairness, not through the market value of addresses. If a transfer requirement is necessary to prevent abuse, the abuse should be described and measured where possible. If a rule exists mainly because it was inherited from allocation-era conservation, it should be reconsidered under post-exhaustion conditions. Legitimacy grows when rules can survive a change in economic context.

IPv6 does not settle legitimacy

No serious analysis of post-exhaustion legitimacy should deny that IPv6 is the long-term technical answer. The larger address space removes the scarcity that made IPv4 governance so difficult. IPv6 deployment reduces dependence on transfer markets, carrier-grade NAT and address sharing. It is rational for ARIN, other registries, network operators, vendors and public bodies to encourage IPv6 adoption. But the claim that IPv6 is the answer can become a way to avoid the legitimacy problem of the transition period.

The transition has already lasted longer than many early statements implied. IPv6 adoption has grown substantially, but IPv4 remains commercially necessary. Persistence is not just irrational inertia. It reflects installed equipment, customer premises devices, enterprise systems, application dependencies, security models, supplier contracts, uneven regional deployment and the simple fact that a service unreachable over IPv4 still fails for many users. For a new network or a growing service provider, IPv6 does not eliminate the need to interoperate with the IPv4 world. It changes the amount and type of IPv4 required.

If ARIN frames post-exhaustion governance mainly as a bridge to IPv6, it risks understating the duration and value of the bridge. A bridge that lasts decades becomes infrastructure. Its governance must be judged on its own terms. Transfer-market integrity, legacy certainty, registry accountability and member power are not distractions from IPv6. They are the institutional conditions under which the Internet operates while IPv6 adoption remains incomplete.

There is also a distributional issue. Large incumbents often have enough IPv4 to manage the transition more comfortably. They can buy blocks, deploy large-scale NAT, operate dual-stack networks and absorb legal and technical costs. Smaller entrants face higher relative costs. A policy environment that says "deploy IPv6" while leaving IPv4 access expensive and administratively complex can entrench incumbency. It may be technically coherent but economically regressive. ARIN cannot solve the global transition economics alone, but it should not pretend that exhortation substitutes for fair post-exhaustion rules.

Nor is the transfer market simply an obstacle to IPv6. It can both delay and enable transition. Buying IPv4 may reduce immediate pressure to deploy IPv6. But predictable access to a modest amount of IPv4 can also allow a new network to launch while deploying IPv6 from the start. If IPv4 becomes obtainable only through opaque arrangements, entrants may choose worse technical compromises. A legitimate registry should care less about moralising the market and more about shaping it so operational necessity does not become institutional rent.

The official IPv6 story is therefore best treated as a technical horizon, not a legitimacy theory. The registry still needs an account of why its transfer rules are fair, why its membership model remains accountable, why legacy holders should trust agreement paths, why entrants should trust the market and why the public should trust the registry record. IPv6 may reduce the problem over time. It does not dissolve it in the next 12 to 24 months.

Inter-regional transfers and the North American export question

ARIN's legitimacy is also tested by inter-regional transfer policy. North America inherited and accumulated substantial IPv4 holdings. Other regions, especially those with later Internet growth or different exhaustion timings, have their own scarcity profiles. Inter-regional transfers allow address space to move across registry boundaries when policies are compatible. ARIN's public guide treats APNIC, RIPE NCC and LACNIC as having ARIN-compatible transfer policies, while AFRINIC is not approved for transfers with ARIN under the listed compatibility status. The requirement for reciprocal, compatible, needs-based policy is meant to protect registry principles across borders.

Inter-regional transfers raise a difficult fairness question. If North American legacy and allocated space moves abroad, is that efficient global reallocation or a drain on regional entrants? If ARIN restricts outbound movement, is that regional stewardship or protectionism for North American buyers? If it allows movement, does it merely recognise that the Internet is global and that addresses are valuable where demand is highest? The allocation-era service-region idea does not fully answer these questions because the post-exhaustion market does not respect regional moral boundaries as cleanly as the original registry map.

The proper answer is not to treat North American space as a national reserve. ARIN is not an industrial-policy body for the United States or Canada, and its region includes many smaller economies whose needs should not be submerged under American market logic. Nor should ARIN pretend that regional history is irrelevant. Compatible-policy checks suggest that inter-regional movement must preserve more than private price discovery. It must preserve enough policy symmetry that a transfer does not become regulatory arbitrage.

The legitimacy challenge is intensified by the ledger problem. Once a block moves to another regional registry, the authoritative record and service environment change. Parties need confidence that the transfer is final, that routing security can be re-established, that dispute history is resolved and that no gap opens between the economic transaction and the public record. ARIN's role is not to decide global justice in the abstract. It is to ensure that inter-regional movement does not weaken trust in the registry system.

This requires discipline. Compatibility should be explained in terms market participants can understand. Changes in compatibility status should be predictable and evidence-based. The effect on small regional networks should be considered. Inter-regional statistics should be published in a way that helps the community see whether North America is a net source, sink or balanced participant in the transfer market. If outbound transfers are large, ARIN should not panic, but it should understand the distributional consequences. If inbound transfers grow, it should understand what that says about regional demand and pricing.

Inter-regional transfer policy is where ledger and governance meet geopolitics. IPv4 scarcity has unequal historical roots. Some regions received more earlier; others grew later. A registry that ignores this history will sound tone-deaf. A registry that tries to correct history through discretionary obstruction will exceed its institutional foundation. A credible post-exhaustion registry records lawful, policy-compliant movement while making the public consequences visible.

Ledger, gatekeeper and the boundary of institutional power

The distinction between ledger and gatekeeper is the central conceptual tool for ARIN's next phase. A ledger records authoritative facts about who is responsible for which number resources. A gatekeeper decides who may enter a market or obtain a benefit. Every registry must do some gatekeeping at the moment of first allocation, because it decides who receives a scarce public resource from a common pool. After exhaustion, however, the resource being transferred is already associated with a holder. The registry's role shifts toward verifying the legitimacy of change and preserving public-interest constraints.

A ledger-centred registry is strict about identity, documentation, finality and data quality. It does not trivialise fraud. It does not rubber-stamp transactions. It does not ignore disputes. It does not allow private contracts to override requirements that protect routing and registration integrity. But its default orientation is to make truthful transfers possible. It assumes that movement from a holder that no longer needs a block to a network that does need it is generally beneficial if the record remains accurate and technical externalities are managed.

A gatekeeper-centred registry is more tempted to decide whether the market's allocation of resources is substantively desirable. It may use need criteria not merely to prevent abuse but to ration market access. It may use agreement requirements not merely to preserve accountability but to draw legacy holders into terms they regard as unrelated to transfer integrity. It may use service access to induce policy compliance. It may interpret ambiguity conservatively in ways that favour incumbents with counsel and experience. The danger is not one spectacular abuse. It is the slow drift from registry verification into economic administration without the safeguards of a public regulator.

ARIN occupies an uncomfortable middle ground because IPv4 addresses are not ordinary private assets. If they were, the registry could be a simpler recording office. But addresses impose public externalities. Fragmented transfers can affect routing. Bad records can affect abuse response. Weak chain-of-control checks can facilitate hijacking or fraudulent sale. Inconsistent inter-regional rules can create arbitrage. Because of these externalities, ARIN must retain more authority than a land-recording clerk. Yet because the free pool is gone, it should exercise less allocation-style discretion than a planning body. The legitimate post-exhaustion role is not minimal. It is bounded.

Bounded authority has practical signs. Requirements should be tied to specific harms. Review timelines should be predictable. Documentation standards should be clear enough for ordinary organisations, not only specialists. Policy changes should include analysis of market consequences. Legacy agreement terms should be stable enough to earn reliance. Fee changes should be explained through service cost, fairness and sustainability. Security-service access should be designed to maximise adoption without making holders feel trapped. Disputes should have transparent pathways. Public reporting should help outsiders distinguish institutional caution from institutional inertia.

The ledger role also demands technological seriousness. RDAP, Whois data quality, reverse DNS, RPKI, IRR, automation interfaces, historical data and fraud reporting are not peripheral services. They are how a registry converts institutional legitimacy into operational trust. A registry that speaks well about community but maintains poor data will lose authority. A registry that maintains excellent data but cannot explain transfer decisions will also lose authority. In a post-exhaustion world, trust is both technical and procedural.

Legitimacy risk over the next 12 to 24 months

The next 12 to 24 months will probably not be defined by a single dramatic ARIN decision. The risk is cumulative. IPv4 prices may move unevenly. Cloud and hosting demand may keep pressure on the market. Legacy holders may reassess agreement status after the fee-cap change. Security expectations around RPKI may rise. Smaller networks may find that the administrative and financial cost of IPv4 access shapes their ability to compete. Election participation may show whether governance remains broad or becomes concentrated among repeat actors. Transfer statistics may show whether policy friction is stable or growing. Each development is manageable alone. Together they determine whether ARIN's post-exhaustion legitimacy deepens or thins.

The first watchpoint is transfer predictability. If ordinary specified-recipient and merger-related transfers are handled within expected time frames, with clear documentation requirements and low surprise, the market can adapt. If delays or denials appear arbitrary, the market will price institutional uncertainty. That benefits insiders and penalises smaller participants. It may also make informal control arrangements more attractive, leaving the public record behind economic reality.

The second watchpoint is legacy engagement. The expiry of the legacy fee cap for new coverage after 2023 should be watched not only as a billing issue but as a trust signal. Are legacy holders entering agreements, staying outside or engaging only minimally? Is RPKI access drawing holders in, or are costs and terms discouraging them? Are records becoming cleaner? Are disputes declining? A registry that can show improved certainty will strengthen its claim. A registry that sees holders retreat into non-agreement status will face a harder public-interest problem.

The third watchpoint is member power. ARIN's requirement that General Members maintain election participation may improve governance quality if it keeps voting contacts current and engaged. It may weaken perceived legitimacy if the voting base narrows to organisations with the strongest capacity. The institution should treat participation data as governance health data. It should care who participates by organisation type, size, geography and resource interest. A formally open registry that is substantively dominated by a narrow band of actors will struggle to justify policy choices that affect the whole market.

The fourth watchpoint is the treatment of IPv6 advocacy. If IPv6 promotion is used to minimise IPv4 governance concerns, the institution will look evasive. If IPv6 is presented as the long-term technical path while ARIN improves IPv4 transfer transparency, legacy certainty and security services, the two agendas reinforce each other. A mature institution can say both things: the future should be less dependent on IPv4, and the present still requires accountable IPv4 governance.

The fifth watchpoint is service leverage. RPKI, IRR, RDAP and related services will become more important, not less. ARIN should be careful that access conditions look like accountability requirements rather than pressure tactics. The more essential a service becomes for safe routing, the more sensitive the legitimacy of any agreement requirement becomes. The institution should be able to explain why each condition is necessary, proportionate and stable.

The sixth watchpoint is the public language of scarcity. If ARIN and the surrounding community continue to speak as if IPv4 has value only in a grudging or unofficial sense, policy debate will be less honest. If they speak as if addresses are ordinary property, they risk undermining the public coordination basis of the registry system. The better language is operational control over a scarce, globally unique number resource. It recognises value without abolishing stewardship.

What a post-exhaustion legitimacy theory should contain

A credible theory for ARIN's post-exhaustion legitimacy would have several parts, and none requires abandoning existing structures. It would first state that the registry's primary IPv4 role has shifted from first allocation to record integrity, transfer assurance, security enablement and fair market governance. Conservation would not disappear, but its purpose would change. Conservation would no longer be mainly about stretching a free pool. It would be about preventing market behaviour that undermines routing, registration accuracy and operational accountability.

It would define the ledger role explicitly. ARIN should be strict about chain of control, identity, agreement status, dispute flags and data quality. It should be modest about shaping private business strategy. It should distinguish requirements that protect the shared number system from requirements that merely continue allocation-era habits. That would help buyers, sellers, legacy holders and entrants understand the boundary of institutional power.

It would treat legacy resources as a public-certainty problem rather than a moral exception. The aim should be to make old space more legible, secure, transferable where appropriate and connected to modern services under terms that earn trust. Fee policy should be cost-grounded and predictable. Agreement terms should be stable. RPKI access should maximise adoption while preserving accountability.

It would make member power accountable to scarcity effects. Participation should remain open, but the institution should report enough about governance participation to show whether the post-exhaustion community is broad. Policy analysis should consider who gains from transfer restrictions, fee changes, agreement requirements and service conditions. Conflicts of interest in a broad sense should be treated as normal data, not scandal.

It would measure and publish transfer-market performance. Not confidential prices, private contracts or sensitive documents, but enough aggregate and categorical evidence to show whether the registry is predictable, timely and even-handed. A market cannot trust a black box simply because the box is not-for-profit. Finally, it would keep IPv6 in its proper place. IPv6 is the destination. It is not an excuse for weak IPv4 governance during the journey. The more credible ARIN is in managing post-exhaustion IPv4, the more credible its IPv6 advocacy becomes, because operators can see that the institution is not using the future to avoid the present.

These elements would not require ARIN to reinvent itself. They would require a sharper explanation of why old forms remain adequate under new economic conditions. That distinction matters. Institutional legitimacy rarely fails because forms vanish overnight. It fails when forms continue while their social meaning changes and no one updates the theory.

Conclusion: ARIN as the hard case

ARIN's post-exhaustion legitimacy matters beyond North America because it exposes a general problem for scarce digital-resource institutions. The hard part of governance begins after the original distribution story loses explanatory power. A registry that once allocated from a pool becomes a registry that verifies transfers. A policy process that once rationed future access becomes a policy process that affects existing asset values. A membership body that once expressed operational community becomes a venue where scarcity rents may be defended, contested or redirected. A legacy record that once looked historical becomes a live instrument of market and routing certainty.

The right conclusion is not that ARIN has failed. It is that ARIN's success now depends on a different standard. The institution must be judged by whether it can preserve a trustworthy ledger, enable legitimate transfers, respect historical reliance, prevent abuse, keep member power accountable, support routing security and avoid using technical authority as unchecked market power. Those are harder tests than the allocation-era tests because the distributional stakes are clearer and the easy stock of new IPv4 addresses is gone.

The economics of post-exhaustion legitimacy are unforgiving. Scarcity turns procedure into value. Delay becomes cost. Ambiguity becomes rent. Participation becomes power. Records become market infrastructure. Security services become leverage points. Legacy certainty becomes a public good. If ARIN recognises this openly, it can become a model for a mature registry after depletion: not a nostalgic allocator, not a passive clerk, but a bounded public-interest ledger for a scarce resource that still matters. If it does not, legitimacy risk will accumulate quietly until a transfer dispute, fee controversy, legacy standoff or participation crisis forces the theory into view.

The next phase of ARIN's legitimacy will not be won by repeating that the community governs, that IPv6 is the future or that policy is documented. Those statements may be true, but they are incomplete. The more important question is whether the institution can explain why its power over scarce IPv4 resources remains justified when allocation has given way to market transfer and historical certainty. North America happens to be where the test is most visible. The result will matter well beyond ARIN's service region.

Public exhibits used for this analysis

This article treats ARIN's public descriptions of its service region, organisation, membership, transfer rules, policy manual, elections and legacy-resource services as institutional exhibits. The key public materials include ARIN's region page at https://www.arin.net/about/welcome/region/, organisation page at https://www.arin.net/about/welcome/staff/, membership page at https://www.arin.net/participate/oversight/membership/, elections page at https://www.arin.net/participate/oversight/elections/, transfer guide at https://www.arin.net/resources/registry/transfers/, Number Resource Policy Manual at https://www.arin.net/participate/policy/nrpm/, and legacy-resource page at https://www.arin.net/resources/guide/legacy/.

The broader scarcity context draws on the Number Resource Organization's 2011 announcement that the IANA IPv4 free pool had been depleted at https://www.nro.net/ipv4-free-pool-depleted and on the research paper "A Primer on IPv4 Scarcity" by Philipp Richter, Mark Allman, Randy Bush, and Vern Paxson at https://arxiv.org/abs/1411.2649. These sources are used as factual exhibits for dates, institutional design, scarcity dynamics and documented policy mechanisms. The interpretation above is independent analysis of the legitimacy problem created by exhaustion.