The reason for making this thread is to try and invigorate a serious discussion on just how useful 301 redirecting multiple domains to a single domain is for SEO purposes, what (if any) penalties may be applied, and what everyone's personal experience is in this field. Please only post comments that contribute to the discussion. Speculation, opinion without lack of experience, or saying what the most "logical answer" is, is not what I'm looking for. I'm looking for experience based opinions, as well as examples. Hopefully if we can lead this discussion deep enough we may be able to find out enough evidence to greatly help one another understand the advantages/disadvantages of multiple 301 redirects. So let's use a couple of examples, what are your thoughts on the following: Scenario 1: You have a site that is optimized under the keyword phrase "green widgets". Let's call this site - example1.com for arguments sake. Now say that you register an expiring domain with a Page Rank 4 called example2.com. Let's say this domain gained all of its keyword authority under the term "green widgets". Now if you 301 redirected this domain to example1.com then obviously the page rank and keyword authority would pass to example1.com. If it didn't (such as due to expiration), then the backlinks would eventually pass some keyword authority to the new domain anyway. At the end of the day, you're getting some positive result as you're basically telling Google that your site has moved. So, to sum up - Example2.com 301 Redirects to -> Example1.com - perfectly normal and beneficial as we all know. Now how does this change for Scenario 2: You register 300 domains that all have keyword authority for the term "green widgets". You 301 redirect all of these 300 domains to domain1.com. This should lead to one of two results - Scenario 1) Example1.com gains a heck load of keyword authority from these 300 domains Scenario 2) Some flag is triggered and Google discounts all, or a certain percentage, of the domains. Now going by the philosophy that one site cannot directly harm another site (in the long term), we'll presume that domain1.com cannot have any direct negative penalty applied to it, as the 300 domains 301 redirecting to it are outside of its control. So then, will these 300 redirected domains be of any benefit to example1.com? Will they be of some but little benefit, no benefit, or of great benefit in terms of gaining Keyword Authority under the term "green widgets"? For the example, pretend that the 300 redirected domains aren't newly registered, and all have at least SOME page rank and keyword authority under the term "green widgets". We're also imagining that all 300 domains are redirected STRAIGHT to example1.com. Now if you believe the answer depends upon certain variables (such as when the domains are redirected, their age, how many are redirected at a time etc), then please explain that in your answer. Thoughts and experience are greatly appreciated.