This is price discrimination 101. You can only price discriminate well if you can segment your users. Blocking health ads from remnant inventory is one way to extract more dollars from health marketers.
Through its Check Point technology, LiveRail lets publisher clients put up restrictions and blocks when it comes to what ads can win at an RTB auction.
Looking at the 1.6 billion impressions served by publishers using the Check Point technology, LiveRail found that 16.5% were blocked. Health, drug, and medicine ads were the most likely to be blocked, with 71.4 million blocked impressions. Retail ads were next, with 65.1 million blocked impressions.