Indirect link spamming

• Using guest blogging for the purpose of gaining a link to another website, or websites.

• Spam on other sites (guest books, forums, blogs, and any site that accepts visitors’ comments), placing a desired keyword into the hyperlinked text of the inbound link.

• Using the open edit-ability of wiki systems to place links from the wiki site to a spam site.

• Referrer log spamming

Known mitigations

Google proposed a nofollow tag that can be embedded with links. The PageRank system will not use the link to increase the score of the linked website if the link carries a nofollow tag.