Domain Registry Services Host Company Scam?

A couple of my clients got an email from Domain Registry Services indicating that their domain name was set to expire...they were all 3 months away from expiring.  They were saying we can renew your domain...etc.  Their domains were hosted by GoDaddy and I can't remember the other host site so be prepared to look for that and ignore them.  If you have any questions, you can go to http://Who.Is and look up your domain name and see all the exact specs of your website information.  I recommend doing that at least yearly to see where things sit with your domain.  Be Careful of Scams!  If it doesn't make sense, question it and do your research.