Anyone else may request delisting of addresses or netblocks provided that reverse DNS naming is set to indicate static assignment. SORBS will consider unique names that are not part of a generic naming scheme, or a generic naming scheme with an indication of staticness (we prefer the word "static" being included in the names, but will accept any existing ISP convention if the ISP just informs us of it) as proof of static assignment. Also, the Times to Live of the PTR records need to be 43200 seconds or more. This is an arbitrary limit chosen by SORBS. And of course, the reverse DNS names need to be valid; i.e. the names given in reverse DNS need to map forward to the IP addresses for which they were given.