eMarketer (Insider Intelligence)

eMarketer (rebranded Insider Intelligence in 2021, but still commonly called eMarketer in industry parlance) is the dominant industry research firm for digital media forecasts and benchmarks. Founded in 1996, owned by Axel Springer since 2017. The research products cover global ad-spend by channel, audience media-consumption benchmarks, retailer e-commerce analytics, and ad-tech market sizing.

For DOOH-specific reporting, eMarketer publishes quarterly US pDOOH spend projections, mid-year deep-dives on CTV-vs-DOOH overlap, and annual benchmark reports on attention-metric adoption. The 2026 Year-in-Review report noted that 41% of US CTV/DOOH spend used attention metrics as a primary KPI (up from 12% in 2023) and that sensor-counted impressions had moved from "emerging" to "table stakes for premium networks."

eMarketer's research methodology is similar to Magna: bottom-up vendor surveys, top-down macro modeling, panel-based behavioral benchmarks. The two are often cross-cited; eMarketer's forecasts tend to be 5-10% lower than Magna's on US channel spend (Magna includes more in-house production cost; eMarketer is more strictly working-media).

Other comparable sources: AdExchanger's research vertical, Forrester's media-tech reports, and Pivotal Research (sell-side investment research). For ground-truth on a specific number, practitioners typically cite at least two of these.