If this space is reclaimed on the simplistic basis of "it wasn't in the public routing table yesterday (or ever)" then reassigned, suddenly the original assignee finds their private and confidetial traffic might start leaking out one of their public connections. Great.
May I remind everyone involved in writing RIPE policies, that RFC 2050, which was co-authored by Daniel Karrenburg of RIPE, describes the IP address Assignment Framework in section 3. In paragraph 3 a), it says: the organization has no intention of connecting to the Internet-either now or in the future-but it still requires a globally unique IP address. The organization should consider using reserved addresses from RFC1918. If it is determined this is not possible, they can be issued unique (if not Internet routable) IP addresses. This has been a fundamental characteristic of IP addresses since day 1. In the early RFCs, the term Internet was used to refer to all internetworks using the Internet Protocol(IP) because most people assumed universal interconnectivity. But now we know better and the term Internet only refers to the public Internet, not to the various private IP internetworks that exist. Most of the large international IP network providers, offer both Internet access and IP VPN services. Some of those IP VPNs are actually internetworks between many independent companies or organizations as described by Peter Galbavy. The organizations who connect to private internets continue to apply for PI address space (and also PA address space) at RIPE and other RIRs. IP addresses are *NOT* reserved for the exclusive used of the public Internet, but are available for use of any internetwork which uses the Internet Protocol (IP). And if you talk to routing researchers you will learn that the global routing table is a bit of a myth since it is not guaranteed that you will see 100% of publicly announced addresses at any given point in the public Internet. --Michael Dillon