I have received more than one report that a company that refers to itself as "DNS Services" has been sending out invalid invoices. In each instance, someone receives a physical letter referring to the recipient's website and 'Managed DNS Backup Services' that are being provided and that need to be paid for. To grant legitimacy, the letter directly refers to a pair of name servers - ns3.dnssvc.com and ns4.dnssvc.com. The trouble is, those servers are not name servers, and have not been name servers during the month-long period that I reviewed them (late December 2012 - now). The servers do not respond successfully to any requests on port 53. At the time of this writing, they still do not respond to port 53. Its one thing to make a mistake on an invoice, however I have received two complaints, both with the exact same letter specifying the same DNS information that is incorrect. Both complainants say they have never heard of this company before. DNS Service'...