I've been using AVG Do-Not-Track Google Chrome extension with Chromium. From what I can tell, it simply uses a local database; a small one, I shall add. But, I noticed that its manifest.json file includes permissions to connect to both these domains -http://dnt.cloud.avg.com/ and -http://dntf.cloud.avg.com/. I cannot find much info on them. I search Startpage, but got no useful hits so far. In fact, whenever AVG Do-Not-Track blocks something, it connects to -http://dnt.cloud.avg.com. But, as I mentioned above, it uses a local database. I don't think these domains are meant for updates either. Unfortunately, I cannot track it, because apps such as Wireshark won't work with my connection, due to Winpcap. I may try and see if I can find an e-mail address to contact with AVG. I don't want to register in another forum. Anyway, I blocked access to -http://dnt.cloud.avg.com, and it's still working - it makes sense, as it uses a local database. So, without knowing more details, I wonder if it's sending info to AVG about the websites where the tracking services are being blocked? There's no option in the settings about this either.