Excerpt from RFC3330 (Special-Use IPv4 Addresses, page 2 <quote> 24.0.0.0/8 - This block was allocated in early 1996 for use in provisioning IP service over cable television systems. Although the IANA initially was involved in making assignments to cable operators, this responsibility was transferred to American Registry for Internet Numbers (ARIN) in May 2001. Addresses within this block are assigned in the normal manner and should be treated as such. </quote> Just feed the following into the web-whois at https://apps.db.ripe.net/search/ -rBTinetnum -m 24.0.0.0/8 into the search field and tick the "all" box in the *Global resource Service beta* Hth, Wilfried. PS: for the Internet Archeologists - iirc, back then this was the interesting case of the cable "NET24" allocation, made outside the RIR system :-)