Proof of play: what DOOH uses instead of an affidavit

Proof of play is a digital out-of-home network's record of what each screen actually showed: which creative played, on which player, at what time, how many times. It is what a DOOH campaign is billed and reconciled against, and it is the medium's answer to the broadcast affidavit.

Why the record has to come from the player

Broadcast has one playout chain per channel, and its as-run log is one file. A DOOH campaign runs on a package of screens that may number in the hundreds, each with its own player, its own connection and its own opportunities to fail quietly. A screen can be dark for four hours, a player can fall behind its schedule, a creative can fail to download and leave the slot showing the previous campaign — and none of that is visible from the booking. Only the players know, so the record has to be collected from them and reconciled against what was sold.

What a usable proof-of-play report contains

• Play-level detail — creative, player, timestamp, duration, not just a total
• Delivered against contracted — plays achieved against plays owed for the period, per screen and per package
• Gaps identified — downtime, failed downloads and schedule drift shown rather than averaged away
• A form the buyer accepts — the agency has to be able to put it in front of the advertiser, which in practice means it has to arrive with the invoice rather than on request

Where it gets argued about

Two places. The first is what counts as a play: a screen with nobody in front of it still played the creative, which is why impression-based trading pairs proof of play with an audience measure rather than replacing one with the other. The second is the remedy. A shortfall in DOOH is usually settled in extra plays rather than extra days, because the slot has a fixed share of the loop and the campaign's dates are often tied to something external — see makegood. Both arguments are shorter when the play log, the booking and the shortfall are one record instead of three exports.

In OpenMediaLogic proof of play is reconciled against the booking as the campaign runs, and the certificate the client receives is produced from it. See also DOOH advertising platform and avails for how the inventory is sold in the first place.