Importance of Number of Links on the Page

Any page only has a certain amount of link popularity (Google calls this PageRank and Yahoo! calls this WebRank) which it can redistribute to other pages. Each additional link on a page takes away from how much voting power the other links on that same page get.

A page does not lose link popularity for linking out to other sites, it just splits what link popularity it can give amongst all pages it is linking to. The link popularity of a page is split up amongst the pages internal and external links.

When evaluating a potential link buy it is important to consider how many links are on the page. If you see north of 80 links on a page then you need to consider that you will only be getting a small amount of link popularity from that page. You can make up for this a bit by getting run of site links versus renting individual links.

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Location of Links on the Page
Ideas like these are what make building lots of natural link popularity important.