https://rdap.arin.net/registry/ip/240.0.0.0[https://whois.arin.net/rest/net/NET-240-0-0-0-0]255.255.255.255NET-240-0-0-0-0SPECIAL-IPV4-FUTURE-USE-IANA-RESERVED4255.255.255.255IANA Special UseIU240.0.0.0falsehttps://whois.arin.net/rest/org/IANAAddresses starting with 240 or a higher number have not been allocated and should not be used, apart from 255.255.255.255, which is used for "limited broadcast" on a local network.
This block was reserved by the IETF, the organization that develops Internet protocols, in the Standard document and in RFC 1112. The documents can be found at:
http://datatracker.ietf.org/doc/rfc1112240.0.0.02013-08-30T14:39:06-04:004