Microsoft will deprecate its public Prebid Cache in 2026
Microsoft Xandr has announced the deprecation of its public Prebid Cache, formerly AppNexus, effective April 30, 2026. This change requires implementers using this cache for video creatives with Prebid.js and Prebid Server to migrate to alternative local client-side or server-side caching solutions. Microsoft recommends local caching for improved customer experience and reduced bandwidth, and will continue to support the Prebid.js community.
Key Takeaways
- The public Prebid Cache, formerly AppNexus and now hosted by Microsoft, will be deprecated on April 30, 2026.
- Prebid.js and Prebid Server implementations using `http://prebid.adnxs.com/pbc` must migrate video creative caching to another solution.
- Microsoft lists local client-side caching, client-side caching, and server-side caching on a non-Microsoft host as alternatives.
- Microsoft says local caching is the preferred method because it offers a smoother customer experience and reduced bandwidth.
- Microsoft says it will continue working with the Prebid.js community on niche use cases.
Why It Matters
This creates a hard migration deadline for publishers and ad-tech teams that rely on Microsoft’s public Prebid Cache for video creatives. The immediate task is replacing `http://prebid.adnxs.com/pbc` with a local or non-Microsoft server-side cache in Prebid.js or Prebid Server setups. For the broader ecosystem, the notice reinforces local caching as Microsoft’s preferred pattern and keeps support aligned with the Prebid.js community. What to watch next is whether Microsoft publishes additional implementation guidance or deprecation details before April 30, 2026.
Read full article at learn.microsoft.com