Published on April 15th, 2019
In recent blogs on IPv4 Price Trends and IPv4 Transfer Market Volumes, we have introduced the topic of IPv4 market sizing. It is clear to us that the number of IPs transferred is driven by large transfers from the holders of /8 blocks. In this blog, we are going to assess the potential future size of the IPv4 transfer market, as measured by the number of IPv4 addresses transferred. We will not consider the number of transfers, which could grow as companies transfer more and more small blocks. Below we examine what has happened so far and what could happen in the future.
We looked at 23 /8  blocks held by companies and institutions. In our analysis, we considered only ARIN held /8s, and decided to treat the US Government Department of Defense blocks as unlikely to factor in. The chart below shows our findings.
We discovered that a total of 1,869 /16s have been transferred out of the 23 /8s. This accounts for 32% of those /8s having already been sold or transferred.
There are 256 /16s in every /8, which implies there are 4,019 /16s left in these 23 /8s (68% of the /8s remain). Of course, some of the /8 holders may have no intention of ever selling, and some /16s may be in use by their owners. If we assume that 50% of the remaining /8s will transfer, then there could be 2,010 /16s sold in the future. This is slightly more than the 1,869 /16s already transferred out of the 23 /8s. Our analysis implies the large /8 market could still possibly transfer as many /16s as have already moved to a new owner.
 23 /8 holders: General Electric, Level 3 Communications (x2), IBM, AT&T (x2), Xerox, Hewlett-Packard (x2), Apple, MIT, Ford, CSC, Halliburton, Merit, Cogent, Eli Lilly, Amateur Radio, Nortel, Prudential, DuPont, Merck, US Postal Service.