News
Technical Blueprint for IAB’s Next-Gen Hero Ad Formats
Beyond the Mid-Roll: A Technical Blueprint for the IAB’s Next-Gen “Hero“ Ad Formats
1 September, 2026
The streaming advertising industry has officially entered its next era. For years, the default monetization strategy relied heavily on traditional pre-rolls and mid-rolls, which remain relevant today. But as live sports and premium streaming events grow, publishers need more flexible, less intrusive ways to monetize content without interrupting critical moments.
In late 2025, the IAB Tech Lab took a major step forward by releasing formal standards for advanced streaming ad formats. Defined by the Ad Format Hero Task Force, which included major players like Disney, NBCUniversal, and our partner Castlabs, these guidelines established clear parameters for formats like Squeezebacks, L-Shapes, and Pause Ads.
However, a standard is only as valuable as the architecture built to support it.
Having an agreed specification on paper is one thing. Delivering non-linear formats dynamically, addressed per viewer and rendered seamlessly across a fragmented device ecosystem, presents a complex technical challenge.
That is exactly the challenge Ad Insertion Platform (AIP) and Castlabs are working together to solve.

The Complexity of Non-Linear Monetization
The goal for modern publishers is clear: expand ad inventory by introducing additional monetization opportunities alongside standard commercial breaks. During a live sports event or content lacking proper ad markers, triggering a targeted L-Shape or Squeezeback ad allows viewers to remain connected to the action while advertisers deliver a relevant message. Making non-linear ad formats work smoothly and trigger automatically based on specific rules or with content detection requires a clear, well-orchestrated workflow between the video player and the ad routing engine. By combining AIP’s AdBlendr (Server-Guided Ad Insertion) with Castlabs’ PRESTOplay player technology, publishers get a clean, highly efficient division of labor.
How AdBlendr and PRESTOplay Work Together
When PRESTOplay detects ad break markers (inserted by AdBlendr based on SCTE-35, specific rules, or content detection) in the stream manifest, it issues an ad decision request to the SGAI layer. Acting as the intelligent orchestration engine, AdBlendr then calls one or multiple ad servers in real time, applies complex business and compliance rules (including inventory splits and promotional priorities), assembles the optimized ad pod, and returns it to the player for playback. This direct coordination unlocks the IAB’s Next-Gen Ad Formats natively. Because AdBlendr handles the heavy lifting of routing and sequencing on the server side, PRESTOplay can execute the playback perfectly on the client side, dynamically adjusting the video viewport for Squeezebacks and Overlays, or triggering Pause ads on a per-viewer basis without interrupting the stream
Through this joint architecture, publishers retain total control over their inventory while seamlessly delivering:
-
Squeezeback Formats: Includes L-Shape and Double Box variants that keep live-action on the screen
-
Overlays: Non-disruptive, highly targeted graphical elements.
-
Pause Ads: Capitalizing on user-initiated breaks without intruding on active viewing.
Crucially, every single one of these formats can be delivered on a per-viewer basis. Two viewers watching the same live stream will see different L-Shape ads based on their individual targeting profiles, all rendered flawlessly across the devices PRESTOplay supports.
Our demo at IBC Amsterdam Building on demonstrations initiated at NAB earlier this year, AIP and Castlabs will feature a joint demo of this SGAI workflow at IBC 2026 in Amsterdam this September.
Whether you are evaluating Server-Guided Ad Insertion workflows or planning your platform’s roadmap for non-linear ad inventory, stop by to see the demo and explore how server-guided routing and advanced player rendering can work in unison.
Castlabs IBC Stand: BOOTH # 5.F26 (Hall 5)
Book a Meeting with Castlabs
Let us know how we can help you today!
If you have any need on Server-Side Ad Insertion, broadcast ad insertion or ad monetization of your live or on-demand contents, don't hesitate to contact our team.
Get started today