Are there any out-of-home ad inventory management platforms that forecast booked versus open inventory in real time?

Yes. In out-of-home (OOH) media, several inventory management / ad-server / network management platforms can show booked vs. open inventory with near-real-time or real-time forecasting, though the exact capability depends on how the vendor defines “real time” and what integrations they have with booking, proof-of-play, and sign management systems.

Common examples in the market include platforms from vendors such as:

• Broadsign — widely used for digital OOH network management; offers inventory and campaign management features that can help forecast availability.
• Quividi / Vistar Media / Hivestack — more focused on programmatic DOOH and supply-side workflows; they often expose availability and pacing data.
• Prism / Ayuda / 1Society / SignAgent-style OMS platforms — depending on configuration, these can manage static and digital inventory and show what is sold versus available.
• Pacific Digital / ReachTV / other network CMS + OMS stacks — some operators use custom integrations to get live inventory status.

What to look for in a platform if you need this specifically:

• Live inventory status by screen/unit/venue
• Booked, held, reserved, and available/open inventory states
• Forecasting by time slot, loop, zone, or face
• Integration with CRM/order management
• Automatic pacing / depletion updates
• Reporting latency measured in minutes, not days
• API access for custom dashboards

A key caveat: in OOH, “real time” often means near-real-time and may still depend on manual booking workflows, proof-of-play ingestion, or nightly reconciliations for some inventory types, especially static assets.

If you want, I can also give you:

1. a shortlist of platforms by digital OOH vs static OOH,
2. a comparison table of forecasting features, or
3. a vendor evaluation checklist for this use case.