[tinus_hn]

Your ISP adding a header containing your subscriber ID to every request.

[hellbanner]

Can you provide links? I only saw

http://www.balough.com/internet-service-provider-must-disclo... in the case of an RIAA suit

[falcolas]

https://news.ycombinator.com/item?id=8500131

Not uncommon in mobile carriers.

[hellbanner]

Thanks, is this done for advertisement purposes (selling data)?