Update VPAID references to VAST 4.3 + SIMID 1.2

[alexbj75]

Summary

VPAID is referenced in the ad-insertion section. VPAID has been actively deprecated by the IAB Tech Lab since 2017 and has been replaced by VAST 4.3 and SIMID 1.2 (Secure Interactive Media Interface Definition). Presenting VPAID as a current standard is misleading for newcomers.

What needs to change

Mark VPAID as legacy/deprecated

Any reference to VPAID should include a note that it is deprecated. Major ad platforms (Google, SpotX, etc.) have dropped or restricted VPAID support due to security vulnerabilities and measurement fraud.

Add current standards

• VAST 4.3 — The current production standard for video ad serving. Used by virtually all major ad servers and demand-side platforms in 2025–2026. Introduces improved measurement, viewability, and interactive capabilities.
• SIMID 1.2 (Secure Interactive Media Interface Definition) — Replaces VPAID for interactive video ads. Sandboxed, secure, works within modern browser security models unlike VPAID (which required full JavaScript execution in the player context).

Context for writers

VAST 4.3 + SIMID 1.2 together provide everything VPAID promised (interactive ads, measurement callbacks) but in a secure, standardized way that works across modern streaming platforms.

References

• IAB VAST 4.3: https://iabtechlab.com/standards/vast/
• IAB SIMID: https://iabtechlab.com/standards/simid/
• IAB VPAID deprecation: https://iabtechlab.com/blog/updated-guidance-for-vpaid-deprecation/

[aleksUIX]

Strongly agree with the direction. Two factual corrections before this gets written, since onboarding docs tend to get copied verbatim and a wrong version number propagates.

SIMID 1.2 is not released

The latest tagged release in the IAB SIMID repo is v1.1, published 2022-01-25. Before that, v1.0 in 2019. There is no v1.2 tag or release.

A SIMID 1.2.md file does exist on main, and there are open working-group issues against it (for example SIMID#412 on L-shaped ad support, still marked "More Discussion Needed"). So 1.2 is a draft in progress, not a shipped spec.

Recommending SIMID 1.2 to newcomers would point them at something they cannot implement against a stable reference. SIMID 1.1 is the right version to name.

VPAID deprecation started with VAST 4.1, not 2017

The VAST spec is explicit about when and how. From VAST 4.3, in the 4.1 change summary:

Deprecating Video Player Ad-Serving Interface Definition (VPAID): While VPAID will likely be in use for some more time, with VAST 4.1 we are taking the first steps to officially deprecate the use of VPAID. The apiFramework attribute on MediaFile, and the conditionalAd attribute [...]

and:

With VAST 4.1, the working group has also deprecated the "apiFramework" attribute on the MediaFile node, which enables the delivery of VPAID.

VAST 4.1 was published in 2018. "Actively deprecated since 2017" predates the mechanism by which it was actually deprecated.

The more useful framing for newcomers is the concrete one: what got deprecated is MediaFile@apiFramework and Ad@conditionalAd, and the replacement path is <InteractiveCreativeFile>, added in VAST 4.0. That gives a reader something they can look for in a tag rather than a date.

One addition

Worth mentioning OMID (Open Measurement Interface Definition) alongside SIMID. The doc says "VAST 4.3 + SIMID 1.2 together provide everything VPAID promised (interactive ads, measurement callbacks)", but VPAID's measurement role was split off to OMID, not SIMID. SIMID handles interactivity; OMID handles viewability and verification via <AdVerifications>. A newcomer who reads that VPAID was replaced by SIMID alone will go looking for measurement callbacks in the wrong spec.

So the accurate replacement story is three parts: VAST 4.x for serving, SIMID 1.1 for interactivity, OMID for measurement.

I wrote up the deprecation timeline and what actually replaced each piece of VPAID at https://vastlint.org/docs/vpaid-deprecated/, which may be a useful cross-check for the rewrite.

Happy to open a PR with the corrected section if that is useful.