Hi,
Permanenent transfer cost [...]
Please remember that the current transfer policy explicitly states "This re-allocation may be on either a permanent or non-permanent basis." so you can already use the current transfer policy for temporary transfers.
After temporary transfer you can receive back IPs which listed in Spamhouse. I don't know any company which will temporary transfers IPs.
But exactly the same can happen with sub-allocated address space. Why would transfers be any different? At least with a transfer you can show that the responsibility for those addresses was (temporarily) transferred to another organisation. With sub-allocated addresses the responsibility remains with the original holder, who would then probably even have a bigger problem explaining everything and getting off the spam lists. This seems to be an argument *in favour* of using temporary transfers... Sander