Evidon [1] is what you are looking for. It's not exactly the way you describe it. More like an alpha stage of what you talk about. There are little boxes in th

Evidon [1] is what you are looking for. It's not exactly the way you describe it. More like an alpha stage of what you talk about. There are little boxes in the corner of website banners (served from the more reputable companies) which leads you to a page telling you why you were served that ad and giving you a list of companies who have data on you. You can through them and chose to opt-out. They have a timeframe to delete that data. Currently everything absolutely voluntarily. Google have their own variation of this called "ad choices" you can find it on youtube and other adsense properties. [1] https://www.ghosteryenterprise.com/ https://www.ghosteryenterprise.com/ PS: They are a commercial entity and develop the popular ghostery plugin, which does the same, but pro-actively.