Best bit of advice yet in this thread.

Natlib could obviously have handled this in a smoover manner[1], but seriously, people are getting a bit carried away here. 

Robots.txt is not an authentication mechanism, and threatening to sue/invoice people who view information from your publicly accessible website (regardless of if they did so over a domestic or international link) when the whole point of putting that information on said public website and then advertising it domestically and internationally is to present that very information for people to view ... complaining about it when someone does that seems a bit precious. 

I think your reaction should maybe be to roll your eyes, possibly even mutter something like "Dammit!" and maybe then reconsider your hosting options if someone doing one complete scan of your site can influence your  charges so much that it hurts.

JSR

[1] They could have said things like "Damn, girl!" and "Aw-w Yeah-h-h!" and maybe worn a cool hat.

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John S Russell

Big Geek. Doing Geek Stuff.