IAB Tech Lab has released the Live Event Ad Playbook (LEAP) Implementation Guide for public comment, offering a shared technical framework for publishers, advertisers and advertising technology providers managing campaigns around live streaming events. The guidance is designed to make it easier to forecast audience demand before an event and respond to changing viewership while it is underway.
The public comment period runs until November 23, 2026. The guide focuses on implementation of two LEAP components: the Forecasting API and the Concurrent Streams API. Together, they are intended to help advertising partners coordinate inventory planning, campaign execution and infrastructure capacity during live sports, entertainment and other high-demand programming.
Live streaming creates operational pressures that differ from those of on-demand video. Audiences can surge around a decisive play, a major announcement or a scheduled ad break, putting pressure on streaming delivery, ad decisioning and programmatic supply chains. When systems use inconsistent integration approaches or delayed audience information, publishers and buyers can struggle to coordinate inventory and campaign delivery.
IAB Tech Lab says the new guide aims to reduce that friction through common implementation practices. Rather than introducing a new advertising marketplace, LEAP seeks to standardize how participating systems exchange information and respond to changes in live-event audiences.
Two APIs Connect Planning With Real-Time Execution
The LEAP Forecasting API supports pre-event planning by allowing buyers and sellers to exchange information about upcoming events, expected audiences, available inventory and campaign opportunities. This information can help participants prepare budgets, inventory strategies and delivery infrastructure before viewership peaks.
The Concurrent Streams API provides near-real-time viewership signals while an event is in progress. Those signals can inform decisions such as infrastructure scaling, campaign pacing and bidding, helping participants respond to changes in audience demand rather than relying exclusively on earlier forecasts.
The implementation guide addresses practical integration details, including authentication, request and response handling, identifiers, polling, error handling, rate limits and operational considerations. These details can be consequential when multiple platforms need to exchange information reliably under tight time constraints.
The goal is interoperability: a more consistent way for publishers, supply-side platforms (SSPs), demand-side platforms (DSPs) and other partners to implement the APIs across different technical environments. A common approach could reduce duplicated engineering work and make it easier to expand LEAP integrations across business relationships.
IAB Tech Lab EVP of Product and COO Shailley Singh said the guide is intended to translate progress on LEAP into practical implementation guidance, so industry participants can spend less time resolving integration differences and more time improving advertising experiences.
Market Landscape: Live Events Test Programmatic Infrastructure
The guide arrives as live sports and other major events become important use cases for streaming and connected TV (CTV) advertising. These environments require coordination across content delivery, ad decisioning, inventory availability and campaign execution, often within seconds.
LEAP’s emphasis on shared forecasts and current viewership signals addresses one specific challenge: making the advertising supply chain more responsive to sudden changes in audience size. If implementations are consistent, publishers and buyers could spend less time building custom integrations and have a clearer basis for planning capacity and campaign delivery.
Industry participation is central to the initiative. The Trade Desk, Amazon Ads and Index Exchange are among the companies whose representatives highlighted the value of common implementation practices in the announcement. Their involvement reflects the need for coordination across buying platforms, advertising infrastructure and publishers.
However, a common API guide alone cannot guarantee smooth playback, accurate forecasts or improved campaign outcomes. Performance will depend on adoption, data quality, latency, system reliability and how effectively each participant integrates the APIs into existing workflows. The announcement does not provide quantified results for integration time, advertising yield or delivery performance.
Strategic Outlook
The LEAP Implementation Guide is an implementation-focused step toward making live-event advertising more predictable and scalable. Its practical value will depend on whether publishers, ad platforms and other participants adopt compatible implementations and use shared signals consistently.
IAB Tech Lab also outlined further work, including Phase Three implementation guidance, Phase Four work focused on creative readiness, continued development of version 1.1 of the Forecasting and Concurrent Streams APIs, and standardized ad pre-fetching. These areas point to a broader effort to coordinate not only audience information but also the operational readiness of ads before they need to play.
For programmatic advertising teams, the public comment period offers an opportunity to identify gaps before the guidance advances. Feedback from engineers, platform operators and buyers may be particularly important for testing whether the proposed practices work across varied infrastructure and real-world event conditions.
Top Insights
- Shared implementation guidance: LEAP’s guide aims to standardize how partners implement two APIs for live-event advertising.
- Forecasting before events: The Forecasting API supports planning around expected audiences, inventory and campaign opportunities.
- Signals during events: The Concurrent Streams API provides near-real-time viewership information that can inform pacing, bidding and capacity decisions.
- Operational detail matters: Authentication, identifiers, polling, error handling and rate limits are included in the implementation guidance.
- Further development is planned: Creative readiness, API version 1.1 and standardized ad pre-fetching are among the initiative’s future work areas.
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