Originally Posted by crankydave

Now, either the author doesn't understand what exactly PR "leak" is or they are addressing all those who misunderstand it and what a simple and very narrow concept it refers to. It's very easy to say it "doesn't exist" to all the folks that misunderstand it rather than to try and explain it. I've tried to do the latter but it's always turned into a full blown mess. Perhaps I'll try one more time for you John and see if it makes sense.

1. A page has a finite amount of PageRank it can pass to other pages.
   
2. That PageRank is passed via the links on the page.
   
3. Those links on the page can be external links or internal links.
   
4. Any amount of PR that is passed via external links is not passed within the site.
   
5. The amount of PR that is passed, or "voted" if you like, by the external link is commonly referred to as being "leaked" because it is not being passed internally.

Example 1... If all the links on a page are internal links then 100% of the available PR is being passed (voted) within the site therefore there is no leak.

Example 2... If all the links on a page are external links then all the available PR is being passed (voted) outside of the site therefore there is a 100% leak.

All a PR leak refers to is the amount of PR that is passed (voted) to external sites that is not being passed (voted) within the site. Anytime less than 100% of the available PR is being passed (voted) within the site, the amount that is not being passed (voted) internally is commonly referred to as a "leak".