Blocking Portscout Scans
There are several known instances of Portscout in the wild. In some cases they are running multiple times a day. This can be an annoyance if you happen to be running a mirror site.
Portscout respects robots.txt rules. However, it can be configured to ignore what I call "blanket bans"; specifically, that means Disallow rules which do not mention Portscout by name. This behaviour is switched off by default.
Effective Blocking
If you do not want Portscout to scan your site, please add the following rule to your robots.txt file:
User-Agent: portscout/* Disallow: /
Allow two weeks for the new robots.txt file to be processed.