I've probably spent $50K on media over the past 9 years on media that was targeted using BlueKai data, and worked on the publisher side where their pixel fired

I've probably spent $50K on media over the past 9 years on media that was targeted using BlueKai data, and worked on the publisher side where their pixel fired billions of times. I remember the early days when its founder Omar was running around the globe selling this data as "Stamps" because they were charging so much for it reaching a single person cost as much as direct mail, printed and delivered. AFAIK, a web request is sent from a consumer's browser with some form of identity, ie cookie ID, fingerprint etc. The hash of it gets sent to BlueKai when there is a bid request, and it then queries for keys associated with that hashed ID. The bidder (a service that makes purchase decisions on bid requests) returns a value for that data, and if its the highest value among all advertisers bidding on that slot the ad is shown. The advertiser never sees any of the underlying data. They are able to see how many bids they won against the pool of data. Say you wanted to sell some organic sausages via banner ads- you would purchase impressions from a publisher, ad network, or agency, and pay an extra $2 CPM (mind you most media clears around $1) to BlueKai to show ads against an Organic Food Buyers audience. That audience is most likely derived from grocery store club card data which include things like recent purchases, brand preferences and more. I'm amazed that more people don't care about that form of data collection... How often do you have to buy organic products to be entered into the targeting pool? 50% of your shopping cart, or 1 item ever? Literally nobody except for BlueKai knows. There is no oversight, and as such the data is almost certainly low quality. I came to the conclusion after all of that spend against at least 100 different audiences that its almost universally more efficient to buy cheaper banner ads in bulk. It was often the case that media targeted with 3rd party data would perform twice as well as untargeted media, but for 5 times the cost. Still, I think the concept of audiences, not raw pii, has been a decent compromise for the sake of privacy, and the net effect of all of it is that some marketing budgets got blown on ads that could have been otherwise targeted. That is one hell of a security risk though to have all of that data sitting out there. I got so fed up with the inequity of digital marketing I've done my best to move myself away from it. If I were building an advertising business today, the consumer would be an equal partner in all data transactions, for two reasons: 1. Fairness 2. Data quality.