Patent ID: 8219549

Claim:
A method comprising: under a control of one or more processors configured with computer-executable instructions: collecting a plurality of webpages from one or more suspect spam websites, the plurality of webpages including one or more posts posted by one or more users for trading links, the one or more posts including a request, a reply, a suggestion, or a recommendation relating to one or more URLs or one or more webpages represented by the one or more URLs respectively, the one or more URLs being distinct from one or more URLs of the one or more suspect spam websites; detecting one or more keywords or language patterns relating to one or more suspicious link exchange URLs that are distinct from the one or more URLs of the one or more suspect spam websites from contents of the plurality of webpages without visiting one or more websites represented by the one or more suspicious link exchange URLs; extracting the one or more suspicious link exchange URLs from the one or more URLs; classifying the one or more suspicious link exchange URLs into a plurality of categories at least partly based on the one or more keywords or language patterns detected in the information, a respective language pattern corresponding to a respective category, the one or more language patterns including a pattern corresponding to a category for link exchange URL, a pattern corresponding to a category for link sale URL, and a pattern corresponding to a category for recommendation exchange URL; and applying a search engine ranking penalty to at least one of the one or more suspicious link exchange URLs, the penalty being at least partially determined by link information associated with the at least one suspicious link exchange URL.