Having domain names with important search terms in them, such as bluewidgets.co.uk, used to give us an advantage in SEO. Google says this is no longer the case, but I suspect it still gives us an advantage in clickthrough rate – people still like to click on URLs which have their search term in them. However, it’s not really the mainstream SEO tactic which it once was.
A legacy result though is that a few companies still have some satellite websites, usually with ‘exact match domains‘, that they set up to target specific searches. Is it a good idea to keep these?
There are two problems with having a whole set of domains and separate websites. One is the maintenance, of course. The other is that the external links to the sites are divided up and diluted over several domains. The advantages of bringing them all together now probably outweigh the benefits of the individually focused sites.
So where this situation exists, I’d consider bringing the external websites’ content into the main one, usually as a page or directory using the same search terms in its name. Obviously, redirect the old domain properly.
The main exception to this would be where the external domain has been created to appear as an independent guide that wouldn’t make sense on a company site. For example, I know one business that successfully broke into a market dominated by three much larger ones, with one initiative being the creation of an ‘independent’ website that fairly ‘compared’ what it described as the four major players in the market…