IPv4 Acquisition Across the Regional Internet Registries

Address space is acquired by taking over someone else's registration rights. You find an organisation holding a block it does not need, agree on terms, and file a request with the registry that manages it. The registry checks both parties against its own policies, approves the move, and updates the public record. Four registries currently allow blocks to cross between their regions, and each one asks for something different.

If you have gone looking for space lately, you already know the free pools are gone. What replaced them is a transfer market. Here is the part that catches people out: there is no single rulebook. The same purchase can be simple in one region and a two month project in another.

This guide walks through that, region by region.

How A Transfer Actually Works

The mechanics are simpler than the paperwork suggests.

Someone holds registration rights to a block. You agree on terms with them. One of you files a request with the registry. The registry checks that both parties qualify, approves the move, and updates Whois so the block is registered to you.

Notice what the registry does not do. It does not find you a seller, it does not set the price, and it does not hold your money. The commercial side is entirely between you and the other party. Registries only care that the transfer itself is legitimate.

One scoping note. This guide is about IPv4. IPv6 and AS numbers can also be transferred, but they follow their own rules in each region, and in one case that difference matters a lot, which we will come back to.

The Words You Will Keep Running Into

Registry documentation assumes you already speak the language. Quick translations:

LIR, or Local Internet Registry, is an organisation that holds a membership with a registry and can receive space directly. Most ISPs and hosting companies are LIRs.

End User is an organisation that holds space for its own network without being a member. In Europe an End User needs a sponsoring LIR to act on its behalf.

PI space, or provider independent space, is assigned to an End User rather than allocated to an LIR, and it moves under slightly different conditions.

Specified transfer means a transfer to a named recipient you have already found, as opposed to a merger or acquisition.

Inter-RIR transfer means the block crosses from one registry region into another.

Who Can Hand Over Space And What Can Move

Eligibility comes before mechanics, and it trips up more deals than anything else.

The source has to be the current registered holder, with no dispute over who owns what. If the original registrant no longer exists as a legal entity, that usually has to be cleaned up through a merger or acquisition transfer first, before anything else can happen.

In Europe, the possible pairings are broader than people expect. Space can move from one LIR to another, from one End User to another, and in either direction between an LIR and an End User. Partial prefixes can be transferred too, so you are not forced to take a whole allocation.

Being eligible to hold space and being eligible to move it are not the same thing, though. That is where holding periods come in, and they vary sharply.

What Changes From One Registry To The Next

	ARIN	RIPE NCC	APNIC	LACNIC
Minimum block	/24	Partial prefixes allowed	/24	/24
Justify your need	Yes, 24 month projection	No	Yes, 24 month use plan	Yes
Holding period	Source cannot have received space from ARIN in the previous 12 months	24 months on IPv4 and 16 bit ASNs	5 years on space from the 103/8 pool	Check current policy manual
Pre-approval	Yes, valid 24 months	Not applicable	Recipient justification on request	Pre-approval step for cross region moves
Registry fee to process	Per fee schedule	None	Per fee schedule	Administrative fee scaled to block size
Cross region partners	APNIC, RIPE NCC, LACNIC	ARIN, APNIC, LACNIC	ARIN, RIPE NCC, LACNIC	ARIN, RIPE NCC, APNIC

North America

ARIN splits transfers into three types. Section 8.2 covers mergers and acquisitions. Section 8.3 covers specified transfers inside the region. Section 8.4 covers transfers crossing into or out of another region.

This is the strictest region on justification. As the recipient, you have to show genuine need, normally by demonstrating how you will use the space within 24 months. There is a second route if you already hold space and can show 80 percent efficient use of it. That route lets you receive an amount equal to your current holdings, up to a /16, and you can only use it once every six months.

Two practical details. The source has to provide a signed and notarised officer acknowledgement letter, which takes time to arrange. And the source cannot have received IPv4 space from ARIN in the 12 months before the transfer is approved.

You can also get pre-approved before you find a seller. ARIN reviews your projected 24 month need, and that approval stays valid for 24 months without needing to be re-justified. If you are shopping in this region, do this first. It removes the slowest step from the critical path.

Europe, The Middle East And Central Asia

RIPE NCC does not ask you to justify need. For a lot of buyers, that alone makes this the easiest region to acquire in.

The trade-off is the holding period. IPv4 addresses and 16 bit AS numbers cannot be transferred for 24 months after they were received, and that clock starts whether the space came from the registry, arrived through a transfer, or moved across as part of a merger or acquisition. There is one carve-out. For transfers between LIR accounts held by the same member, the restriction applies only once.

Worth knowing if you are buying: ask when the seller received the block. A block that changed hands 18 months ago is not available to you yet.

Asia Pacific

APNIC sits between the other two. Recipients provide a detailed plan for using the space within 24 months, so there is a justification step, though it is lighter than ARIN's.

The rule that surprises people here is the five year hold on addresses delegated from the 103/8 pool. Five years is a long time, and it applies to mergers and acquisitions as well, so you cannot restructure your way around it.

One thing APNIC does that the other registries do not is publish a public log of transfers. If you are checking a seller's history, that log is free and it is worth reading.

Latin America And The Caribbean

LACNIC is more open than most people assume. Its policy manual covers transfers inside the region and transfers involving another region under the same section, and since policy LAC-2019-01 became operational, members can offer or receive space across regions without needing a merger or acquisition between the companies involved. The reciprocal partners are RIPE NCC, APNIC and ARIN.

The minimum block size is a /24, the same as ARIN and APNIC. A receiving organisation in the region has to justify its need before LACNIC will approve anything, so this is not a light touch region despite the open cross region stance.

The detail worth planning around is cost. Unlike Europe, LACNIC charges to process a transfer. There is a deposit due when you file, and it is not refunded if the request fails justification, plus an administrative fee that scales with the size of the block. Filing runs through the offering organisation's administrative contact in the member portal, and for cross region moves LACNIC pre-approves its side first, then hands off to the destination registry to assess the receiving organisation.

AFRINIC does not appear on the compatible counterpart lists published by ARIN or APNIC, so African space sits outside the cross region market in practice. Policy in that region has been moving, so it is worth checking directly rather than assuming, but do not build a timeline around it.

Moving Space Between Regions

This is the piece most guides skip, and it is the piece that actually makes a purchase global.

A transfer between two regions only works when both registries have compatible policies. ARIN names APNIC, RIPE NCC, and LACNIC as the only registries with ARIN compatible cross region policies, and APNIC names the same three from its side. Both registries have to approve, which means the stricter of the two effectively sets the bar.

Think through what that means. Buying in Europe because there is no needs test, then moving the block into North America, does not let you skip ARIN's justification. You will face it on the receiving end. The lighter policy only helps you if the space stays where it is.

Here is the IPv6 detail flagged earlier. Cross region transfers involving ARIN cannot include IPv6 addresses. If your plan involves moving both, they are separate exercises.

The Paperwork And Who Files It

Who initiates the request depends on where you are.

In the RIPE region, only the offering LIR can file, or the sponsoring LIR if the offering party is an End User. As the buyer, you cannot start the process yourself. Requests go through the LIR Portal.

In the ARIN region, requests go through ARIN Online, and the source supplies that signed and notarised officer acknowledgement letter. In the APNIC region, the account holder submits, with a separate template for cross region requests. In the LACNIC region, the offering organisation's administrative contact files through the member portal.

The document set is broadly consistent wherever you are. Recent registration documents from the relevant national authority for companies. A transfer agreement signed by both parties. Evidence that whoever signed was authorised to sign for their organisation, which usually comes from the company registration document. Where an individual rather than a company is involved, identity documents, which RIPE verifies through a third party provider.

Registries also screen the parties. RIPE checks both sides against the EU sanctions list and will not approve a transfer where either party is sanctioned.

Where The Blocks Come From In The First Place

Registries approve transfers. They do not introduce you to sellers. Finding the block is entirely on you, and there are four realistic routes.

Direct private sale. You already know a company sitting on unused space, or you find one. Cheapest in theory, since nobody takes a cut. The catch is that you carry all the diligence yourself, and drafting a transfer agreement from scratch is not trivial.

Auction platforms. Open bidding, transparent demand, genuinely useful for larger blocks. The downside is that you cannot plan a budget around a process where the price is decided at the end, and losing bidders have spent time for nothing.

Brokers. They hold seller relationships, they know each registry's quirks, and they manage the process. You pay for that, and quality varies enormously, so check which registry programmes a broker actually participates in rather than taking the claim at face value.

Fixed price marketplaces. Inventory and prices are published upfront. Marketplaces such as IPv4 Connect list blocks at set prices with no bidding cycle, which makes budgeting straightforward. The limit is obvious enough: you can only buy what is listed, so if you need something specific, you may still end up waiting or asking around.

None of these is automatically right. If you need a /24 next month and want a predictable number, a marketplace or a broker makes sense. If you need a /16 and have time, an auction may find you a better price.

Checks Worth Running Before Money Moves

Whichever route you take, the diligence is yours.

Confirm the registrant matches the seller. Pull the Whois record yourself rather than accepting a screenshot. The organisation named there should be the organisation signing your agreement. Mismatches are common when a company has been renamed or acquired, and sorting it out is a separate registry process that has to finish first.

Check that nothing is disputed. Registries will not process a transfer where the status of the resources is contested. Better to find that out before you have negotiated a price.

Confirm the holding period has expired. Ask when the seller received the block, and get it in writing. Twenty four months in Europe, five years for 103/8 space in Asia Pacific. Sellers do not always volunteer this, and some genuinely do not know.

Look at blacklist history. Addresses carry their reputation with them. If a block spent two years sending spam, your mail will land in junk folders from the first day you use it, and your outbound traffic may be filtered by networks you have never dealt with. Delisting is possible but slow, since each blacklist has its own process and some take weeks to respond. Check the block against the major lists before you agree to a price, not after.

Clear the old routing records. Previous holders leave behind RPKI certificates, IRR objects, and live BGP announcements. If a stale route object still points at the old owner, your announcement may be filtered by networks that validate routing data, and you will spend days trying to work out why traffic is not arriving. Who actually does this cleanup depends on your hosting arrangement, so check whether your dedicated server setup puts network configuration on you or on your provider. Either way, agree who removes what, and when, as part of the deal rather than afterwards.

Check geolocation. Commercial databases may still place the block in another country. For anything customer facing this matters more than people expect, because it affects which content users see, which payment options appear, and occasionally whether they can reach you at all.

On payment, escrow is the sensible default. Funds sit with an independent third party and are released when the registry confirms the transfer, which protects both sides. A direct wire ahead of registry approval means trusting a counterparty you have likely never met.

How Long The Whole Thing Takes

No registry publishes a processing time, which is worth knowing in itself. Any timeline you are given is an estimate based on experience rather than a commitment. That said, here is what to plan for.

Agreeing terms and signing usually runs a few days to a couple of weeks, and it depends entirely on how quickly the two parties move.

Gathering documents is where deals stall. A few days if everything is to hand, closer to two weeks if a notarised letter or a fresh company registration certificate has to be arranged.

Registry evaluation is the genuinely variable stage, commonly one to two weeks, longer if anything in the file needs clarifying. This is the part you cannot speed up.

The public record update follows quickly once approval lands, usually within a day.

Plan for two to four weeks end to end for a straightforward transfer inside one region. Cross region transfers take longer because two registries review the same transaction in sequence rather than in parallel. And any gap in the paperwork sends you back to the end of the evaluation queue, not the front.

One more thing on cost, because a line in the RIPE documentation misleads a lot of first time buyers. Resource transfers are free of charge. That refers to the registry's processing fee, not the deal. You still pay the seller market rate for the block, and you still pay membership or sponsoring fees to hold it. Other regions do charge to process. Free to process is never the same as free to acquire.

Making The Call

Choosing a region comes down to three questions. How much justification can you produce? Whether the block you want has cleared its holding period. And where the space actually needs to be routed once it is yours.

Get those three lined up before you start negotiating and most of the friction disappears. Get them wrong, and you will find out weeks later, after the money has already been discussed.

Frequently Asked Questions