This seems to be just as easily cured by setting an internal community on routes from peers, and not specifying "additive" (in ciscospeak):
route-map peer-in set community xxx:yyy
More appropriately, ip community-list exp PRIVATE-AS permit 65[0-9][0-9][0-9]:.* ip community-list exp PRIVATE-AS permit 64[6-9][0-9][0-9]:.* ip community-list exp PRIVATE-AS permit 645[2-9][0-9]:.* ip community-list exp PRIVATE-AS permit 6451[2-9]:.* route-map peer-in set comm-list PRIVATE-AS delete As not to destroy all communities coming in, since preservation of data is good. Ideally you'd want to strip any 'prepend' and selective advertise communities from peers as well, since one would hope they're not depending on you to do TE work for them.... ..kg..