Thank you for pointing this out bromley. I've been reading Gabriel's responses and in no place does he mention that keyword level data is needed for understand

Thank you for pointing this out bromley. I've been reading Gabriel's responses and in no place does he mention that keyword level data is needed for understanding differences in user behavior based on entry keyword. This might not make a difference if you run a content site, but for any type of commerce site, I don't want to know how "Google" does, I want to break it down to the keyword level and better understand where efforts should be focused. I also don't think that the keywords are shared with 3rd party networks explicitly. I think what's happening instead is that you search for something, you land on a page relevant to that something, and the ad network code is reading the content on the page and assigning a keyword target or theme to your search. For example, you might search for a Ford F-150 and you get to Edmunds and the ads are sold on a "by make/model" basis using ad segmentation so the ad network now can assign your cookie a "Pickup trucks" behavioral tag but it never had to read the referrer header, it was implied.