Per the third paragraph on SURBL -- Usage:
The SpamCop-URI-derived SURBL can be found in It includes both domain name an reversed-numeric addresses of SpamCop-reported spam sites in the standard formats: for name-based references, and for numbered references. Matching references return an Address (A) Resource Record of and a Text (TXT) Resource Record currently reading: "Message body contains SpamCop spamvertised domain." In other words, it looks like a typical RBL.
A few links later, the real source is identified: SpamCop's list of Spamvertised Web Sites with reporting in progress at