Comment by rsync

"Apologies to bbtec.net, but I _really_ didn't scan their public IP :)"

There is no need to apologize. There is nothing wrong with port scanning a public IP address. In fact, I just did it myself:

  # nmap -sT 126.16.2.1
  
  Starting Nmap 6.25 ( http://nmap.org ) at 2015-04-06 13:46 PDT
  Nmap scan report for softbank126016002001.bbtec.net (126.16.2.1)
  Host is up (0.12s latency).
  Not shown: 994 closed ports
  PORT      STATE    SERVICE
  80/tcp    filtered http
  340/tcp   filtered unknown
  2103/tcp  filtered zephyr-clt
  8000/tcp  filtered http-alt
  55555/tcp filtered unknown
  55600/tcp filtered unknown

  Nmap done: 1 IP address (1 host up) scanned in 24.78 seconds

No problem at all for anyone involved.