About five years ago I wrote a blog article on IPv4 address brokers and legacy address space. I’ve seen quite a few queries from Jisc’s members about selling some of their address space recently, and some things have changed in the last few years, so it is time for an update.
The first question we are usually asked is whether the institution “owns” the IPv4 addresses it is using. “Ownership” is a loaded term in the addressing community, but it still stands that if you have legacy address space that was assigned directly to your institution (likely to be a /16), that is almost certainly yours to dispose of as you see fit.
If you look up your address prefix in the RIPE database and the resulting ‘inetnum’ object includes the line “status: LEGACY”, that is address space that pre-dates the Regional Internet Registry (RIR) system and was allocated directly to the institution (if you have a ‘whois’ client installed, you can also perform the lookup from the command line, such as “whois -h whois.ripe.net 146.97.0.0”).
If you’re reading this, then you have probably already been approached by an address broker willing to find a buyer for your address space. In my previous blog I referred to a list of address brokers that had agreed to abide by the RIPE NCC’s rules for address trading (the RIPE NCC is the RIR that covers the UK). Unfortunately that list no longer exists as the RIPE NCC thought it was being used as a list of “approved” brokers, which is not what it was meant to be.
That means you will need to do your own due diligence on the broker you’re considering using. Ask them for references, especially within the UK educational community. Some brokers might offer additional services, such as assisting with a deployment of IPv6 as part of the deal.
One thing that has changed substantially recently is the price of IPv4 addresses, and particularly the fact that there is no longer a premium attached to offering a complete /16 for sale. In particular, if you were offering a /16 for sale about a year ago it might have attracted in excess of US$50 per address, whereas now the price is the same as smaller blocks at around US$34 per address.
Whilst this means the sale price for a /16 is lower, that does now mean there is less of an incentive to release the whole address space, and the per-IP sum that you receive is likely to be the same if you retain an amount of addresses (for example a /20) for your own use. Some of the brokers may offer to buy the whole /16 and lease back a subnet of appropriate size. If you choose this route, be aware that you do of course lose control of the address range and will be incurring a recurrent cost.
There are probably a couple of reasons for the convergence of prices, such as a relatively large number of /16s being available (as other institutions go through the same thought process that has brought you to reading this?), and perhaps the main customers for the blocks, the hyperscalers that can afford to spend US$2M on a single address transaction, have fulfilled their needs for the immediate future. Between them, Amazon, Microsoft and Google account for over 75% of the address space bought.
Selling your address space is not the only way of creating income from it. Some brokers may also offer to lease your address space out. Amazon Web Services (AWS) set a price indicator for this when they announced that as of February 1st 2024 all public IPv4 addresses would incur a charge of US$0.005 (half a US cent) per hour. This does mean that a recurrent income might be possible rather than a one-off capital sale, but you are at the whim of the address space market and being able to find customers to lease the address space. You might also want to ensure the address space is leased responsibly, as if it is used to send bulk email it may end up on blocklists and require a considerable amount of effort — and possibly money — to clean up.
One other thing to be aware of is that there is pressure on the RIPE NCC to update its current charging model. Up until this year, “sponsored” resources (many of the legacy resources used by Jisc’s members have Jisc as a “sponsoring LIR” to ensure a contractual relationship) were charged at €50 per resource, which Jisc pays as part of its RIPE NCC membership fee. That is increasing to €75 per resource in 2025. It is not beyond the realms of possibility that there will come a push to increase that further, and perhaps make it banded depending on the size of resource.
In summary, there is still quite an active IPv4 address market, and whilst we cannot tell you what to do with your address space, we will try to help our members and customers that are considering trading in some of that space.
One reply on “An update on IPv4 address trading”
Thanks for an accurate article. It’s interesting how the market responded to inverse economies of scale, we brokers strove to aggregate when price demanded that, and in earlier days, we would deaggregate /16s when smaller blocks sold at higher prices. I don’t think there have been large effects on the routing table, though.