SURBL anti-spam blacklist to be a paid service
The operator team of the SURBL anti-spam blacklist have announced a far-reaching change to the usage policy. While the use of the project's DNS server has been free so far, the list's operators are now demanding a usage fee from service providers that offer spam filter services for more than 1,000 mailboxes or 250,000 emails per day. These service providers are now required to subscribe to a sponsored data service, which will include direct access to SURBL data, as well as support. The funds will be used to ensure the quality and accessibility of the service.
SURBL is a domain and hostname blacklist that can be queried via DNS. Spam filtering software can extract links contained in emails and compare them to the SURBL data.
Users of the open source spam filter package SpamAssassin are likely to be the most affected, since it uses SURBL by default. That could change in the next version of the spam filter. Such a change occurred when a new licence was introduced for Vipul's razor checksum components. SpamAssassin is an essential component of a number of anti-spam appliances. Also, various mailservers and anti-spam products use SURBL data.