For over three years now, I and others (including Danny) have been trying to get information from Google on how they handle passing link value from domain names, specifically in cases of expired domains and domain name transfer of ownership.
In April 2006, I wrote Changing Domain Name Ownership Whois Information & Google Search Ranking Impact. Then Tamar wrote a nice piece summing up the history around this topic about a year ago. Then more recently, Matt Cutts of Google commented on expired domains and if you should 301 them, he said:
Hey Michael! If you buy typos, I'd 301 them to your main site. Even things that you win in UDRP arbitration can be 301'ed. For example, if someone bought porngoogle.com and Google won it in UDRP, it would make sense to 301 it to your main domain.
What I *wouldn't* recommend is try to register unrelated expired domains in an attempt to get those pre-existing links to count toward your domain. I would also avoid registering-and-301'ing typos of competitors' domains or other completely unrelated domains.
That all being said, Danny Sullivan has more details from Matt of Google on this topic. Danny wrote Do Links From Expired Domains Count With Google?. In that piece, Matt Cutts told Danny:
There are some domain transfers ( e.g. genuine purchases of companies) where it can make perfect sense for links to transfer. But at the same time it wouldn’t make sense to transfer the links from an expired or effectively expired domain, for example. Google (and probably all search engines) tries to handle links appropriately for domain transfers.
The sort of stuff our systems would be designed to detect would be things like someone trying to buy expired domains or buying domains just for links.
Danny then analyzed these comments and wrote some scenarios on what types of domains would pass value and which would not. We still don't have Google saying in case X, Google will do B and in case Y, Google will do C. I am not sure if we will ever get there.
But domain name change of ownership happens often enough and communicating to Google what really is happening with that domain, via Google Webmaster Tools, makes sense to me.
Forum discussion at Sphinn.