Referrer - unable to identify the originating page with nested iframes

Hi,
Display advertisements mostly gets served thru iframes.  Per comScore study [1], 61% of iframed ads are delivered via cross-domain or unfriendly nested iframes.  Due to the complex chain of online ad delivery thru ad networks and exchanges, it is not always clear where an ad will appear. But it is important for advertisers to know where their ad is being served

The publisher's adapt iframes to serve display ads to

1.       Play safe - protect the publisher page

2.       Hide things that are not legitimate business practices - categorized as 'not brand safe' by comScore due to [2]

In order to safeguard guanine publishers (case 1) and to not to serve the ads in 'not brand safe' sites (case 2), I was exploring various options:

One bullet proof approach could be to, introduce a additional http request header say 'root-referrer-domain' which carries the value of actual page's domain (just the domain part but not the entire URI).

This would solve the display advertising industry's problem to large extent.

Any concerns to get added into the standards?

Thanks
Bhaskar




[1] (http://www.comscore.com/Press_Events/Presentations_Whitepapers/2012/Changing_How_the_World_Sees_Digital_Advertising)
[2] piracy and copyright theft, child abuse, phishing, fraud, hate speech, nudity etc