Roy supposedly said:
A few years ago, I was surveyed by the Internic as to utilization of space that I owned in a former job. I offered to turn back portions of the space (several class "B" worth). I was never contacted again.
Returning space is easy. If it is "legacy" space just send do the following: (From RFC 1917)
4.3 How to Return a Block of Address Space to the IANA
Send the following form to Hostmaster@internic.net & iana@isi.edu, changing the $NET_PREFIX to the network being returned.
Actually that's now hostmaster@arin.net ;-) Kim
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Please update the contact information on the following net as follows:
Netname: RESERVED Netnumber: $NET_PREFIX
Coordinator: Reynolds, Joyce K. (JKR1) JKRey@ISI.EDU (310) 822-1511 Alternate Contact: Postel, Jon (JBP) POSTEL@ISI.EDU (310) 822-1511
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If it is from a block of addresses assigned by RIPE or APNIC send it to their hostmaster@ripe.net or hostmaster@apnic.net