In my continue series of exposing SEO tools we find this little SEOmoz-bot over at SEOmoz.
I'll give SEOmoz some credit where credit is due in they at least identify their tool as a bot so it can be blocked if you want. However, they don't check robots.txt to see if the bot is allowed as I think they assume it's always going to be used by the site owner but it could just as easily be used on some competitor's site as well.
Here are the IPs and the user agent used:
22.214.171.124 "SEOmoz-bot"The IP's belong to HopOne which provides various services including hosting.
OrgName: HopOne Internet CorporationI think that range is safe to block as it appears they use 'DC' in the net name of their data centers but it's probably worth checking to see what bounces for a few days to make sure.
NetRange: 126.96.36.199 - 188.8.131.52
Of course the best SEO is secure SEO, so block 'em ;)