Big question
When the platform hosts the sale, is it creating demand or claiming credit for it?
The position
Treat a platform-reported sale as claimed rather than caused. The only number you can defend is a holdout you ran, and the thing to price alongside the return is the customer relationship you do not get to keep.
Why it is live
One company can host the browsing, sell the media, close the transaction and report the result, which leaves no party outside the transaction able to check it. Reddit added shoppable discovery in March 2026, and the IAB and IAB Europe published incremental measurement guidance for commerce media in November 2025 because attributed sales were not comparable.
The case for created demand
InferredSocial commerce reaches people who were not shopping when the session began, which is the definition of new demand.
The case against
DocumentedThe seller of the media also reports the result, no platform publishes a category total, and any share of voice figure is a fact about your data contract rather than about the market.
Where the weight sits
Against the platform's own number, and genuinely unsettled on how much of the demand is new. Say both halves out loud, because the second half is what nobody in the room will have thought about.
What would change this
One platform accepting an independent holdout design on its own commerce inventory and publishing the result, or any platform publishing total category conversation volume.
Where this is taught
Connected Social
Sources
- Reddit shopping, 24 Mar 2026primary
- IAB and IAB Europe incremental measurement in commerce media, 3 Nov 2025secondary