Prove your ads actually played.
Proof of Play gives advertisers verifiable evidence that a post displayed on a screen — how many times, for how long, at what hours — as a downloadable PDF for any day, week or month. It isn't an analytics estimate. Every number is measured on the device, cross-checked by independent systems, and anchored with a third party so nobody — including us — can quietly rewrite it.
Three independent layers. Each one checkable.
Tamper-evidence over trust — numbers no single party can silently edit.
1. The screen is the witness
Every item that displays is recorded on the device itself with its measured on-screen time — not the time it was scheduled for. Each record is cryptographically chained to the one before it, and batches are signed with a hardware-backed key that never leaves the box. Altering or injecting history — even with full access to our database — breaks the chain.
2. Cross-examined, independently
Our servers verify every chain and signature on arrival, then a nightly job reconciles what each device reported against things it doesn't control: its own uptime heartbeats and the playlist it was expected to run. Reports that don't add up are graded down — never hidden — and a post that should have played but didn't is flagged as a shortfall.
3. Timestamped by a third party
Every night a cryptographic fingerprint of each screen's day is timestamped by an independent RFC-3161 Time Stamping Authority — an outside body attesting that this exact data existed by this date. We cannot back-date, amend or fabricate a report after the fact. Neither can anyone else.
Honest by design
Most signage tells you what it meant to show. We tell you what actually happened — including when it wasn't perfect.
Verified vs. presented
We sense whether the TV was actually receiving a signal over HDMI. Screen-time we can vouch for is shown as verified; time we can't is disclosed separately — never quietly counted as proof.
A grade on every report
Each report carries a prominent A–D confidence grade based on how well the independent checks agree. We show it even when it's a C — because a number you can't trust is worth nothing.
Gaps, not invented numbers
A device-dark day shows as a gap. An interrupted play counts its real seconds. Anomalies visibly grade the day down. Nothing is smoothed over to look better than it was.
Anyone can check it. No login. No trust required.
Every report carries a unique digest and a QR code linking to a public verification page. An advertiser — or their client — can independently confirm a report is genuine and unaltered, see its confidence grade, and see the third-party timestamps, without trusting whoever handed them the PDF.
Report verified
Device signature & timestamp both check out
Plays
1,204
Verified screen-time
13h 6m
Range
Last 30 days
Timestamped
RFC 3161
Illustrative — open SLX Verify for a live report.
Turn your screens into provable advertising.
Proof of Play is included on the Pro plan. Reports are available to the post's author and the board's admins.