Subnetting legacy Class B networks

> It was recently brought to our attention that RIPE have started to break
> down some legacy Class B networks and assign individual subnets thereof: 
> ...
> This raises routability problems because many backbone operators filter
> out BGP announcements of this range with prefix length longer than /16.
> See for example <http://www.sprintlink.net/filter.htm>. 

for the record, verio also filters B on /16.  we do so because that is what
the registries told us were allocation boundaries.  if registries intend to
change these policies, it would be kind to warn and discuss.

randy