It's impossible to remove that conflict of interest. The search engine maximizes expected utility when serving ads: argmax(predicted-click-through-rate * cost-

It's impossible to remove that conflict of interest. The search engine maximizes expected utility when serving ads: argmax(predicted-click-through-rate * cost-per-click). That's the only rational thing to ask for from an advertising network, and it's what the advertiser optimizes for as well by running the ad auction in the first place. It doesn't matter who computes the ad-quality score (the predictor of click-through rate); rational actors with sufficient information will agree on the value. One could artificially prevent the search engine from e.g. sending keywords and viewer profiles to the ad network, but that is a completely separate regulatory approach from monopoly-busting. While we're stumbling around the regulatory possibility landscape why not just ban advertising altogether? It's a ~1% drain on the economy that people who know better go out of their way to block.