I propose don't allow transfers from last /8 during first 2 years afer date of allocation from RIPE NCC pool.
Example: some LIR get IPv4 from last /8 at 11.08.2014. In period 11.08.2014 - 10.08.2016 transfer of it's IPs are not allowed. Since 11.08.2016 this LIR can transfer IPv4 to any LIR.
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