most recent ARIN issued report [arin-issued] Daily Report for 2025-10-07 Add 131.143.16.0-131.143.19.255 through Add 131.143.235.0-131.143.235.255 131.143.0.0/16 was issued to Rockwell so its easy to see that there could be blocks that existed globally. Trey On 10/8/25 1:04 PM, Ezri Zhu via NANOG wrote:
zgx,
On Wed Oct 8, 2025 at 9:39 AM EDT, Zhang Gaoxing via NANOG wrote:
I have noticed that the number of people on the ARIN Waiting List has been decreasing significantly recently, and some have started receiving IP allocations from the 131.143.0.0/16 range. I also found that these IPs were previously geolocated in Switzerland. Were these addresses reclaimed from an organisation? I’m curious about the origin of these IPs. Have you checked out https://stat.ripe.net/resource/131.143.0.0-131.143.207.255#tab=database yet? it has some nice graphs showing all the historical announcements from that range. Sadly the page takes forever to load due to the size.
However, I failed to find the 131.143.0.0/16 range from the ARIN "Cleared for Waiting List" CSV, may I ask how you found that range?
btw, i'd recommend signing up for https://www.arin.net/reference/research/whowas/ as that's probably your best bet.
let us know how it goes!