IOS XR vrf export route-policy
vrf export route-policy doesn’t seem to directly deny prefixes from advertisement… but according to this one site you can indirectly deny prefixes… it seems that vrf export route-policy is mainly used to more granularly assign rt’s and add rt’s to rt’s (additive).
http://www.akbintel.com/mediawiki/index.php/VRF/Config#export_map
http://nagendrakumar-nagendra.blogspot.com/2011/09/mpls-vpn-vrf-export-map.html
Thought it was pretty clever to not put a route-target export x:x and then whichever prefixes are denied in the export route-policy will drop out of the route-map logic, and this will not be advertised since there isn’t a route-target export statement in the vrf. Cool.