Project Poirot: the hidden Google dial that drained publisher revenue

Ricky Sutton's note, resurfaced in this week's Substack digest, is the sharpest public framing yet of Project Poirot, the covert Google program that is now part of the antitrust record. His version of the story in full: "In 2017, publishers found a way around Google's ad tech. It was called header bidding, and it lifted their revenues by up to 40%. Google's response was Poirot: a hidden dial inside its ad buying tool that turned down the money reaching its rivals. Every campaign was switched on by default. Publishers were never asked. Publisher revenues collapsed as Google grew. Now the evidence is out in the open and a jury has been tasked with solving the case." The antitrust record matches and extends it: Poirot launched in 2017 to suppress DV360 bids on rival exchanges, with a v2 rollout in 2018 escalating bid suppression to 90%, targeting exchanges that used first-price auctions. It matters today because it is the reason the antitrust remedy now centres on the auction mechanics Prebid is trying to rewrite. Sutton's note is a reminder, aimed squarely at sell-side readers, that the money question in programmatic has always been about hidden dials and default settings, not just take rates.

The crux

The Poirot record turns the Prebid auction fight from an abstract plumbing dispute into a question of past theft and future compensation, and gives publishers a concrete, documented grievance to cite in their own negotiations and complaints.

Sell-side read

Poirot is the evidence trail publishers should keep in front of every demand-side and supply-side partner: it explains years of suppressed yield and justifies the hard push for real-time bid transparency through Prebid rather than opaque AdX bid shading.

Watch

the jury's findings in the open antitrust case, which Sutton frames as the moment the case gets "solved", and whether any publisher mounts a follow-on damages claim on the back of it.