IAB Content Taxonomy 2.2 → 3.0: Expanded Media, Richer Mapping, and Descriptive Vectors

If you work in programmatic advertising, contextual targeting, or publisher monetization, the IAB Content Taxonomy is your shared vocabulary for describing content. Version 3.0, announced in September 2021, is the first major update since 2.2 — and while it keeps the same core principles, it expands into new media types, redefines News categorization, and moves several classification attributes into a new descriptive vectors model.

This article explains the changes from 2.2 → 3.0, how descriptive vectors work, and offers a taxonomy mapping from version 2.2 to version 3.0 in order to help you adjust your categorization pipelines.

TL;DR — the essential changes

• CTV/Video support: For the first time, Connected TV buyers and sellers can leverage taxonomy-based contextual targeting via new entertainment genres.
• News expansion: The old Politics and News category is gone. News classification now uses multiple vectors (e.g., purpose, tone) for richer targeting.
• New media types: Added categories for Podcasts, Games, and Mobile Apps, with mappings to popular platform standards.
• Descriptive vectors: Several formerly hierarchical categories (e.g., Content Channel, Content Type, Content Source) are now independent attributes that can be combined with topical categories.
• Category moves/removals: Some nodes were merged, reassigned, or removed entirely — IAB did not publish an official mapping, so we’ve built one.

Why 3.0 happened

The update addresses three industry trends:

1. Rise of CTV advertising — buyers wanted a standard way to target based on CTV genres and formats.
2. Privacy-driven contextual targeting — with cookies and mobile IDs fading, contextual accuracy matters more.
3. Support for news media — giving buyers more control over what kind of news they align with.

Amit Shetty, VP at IAB Tech Lab, summed it up: the update “adds greater clarity for both advertisers and publishers,” especially for new formats and nuanced news content. (IAB Tech Lab, 2024)

Descriptive vectors — what they are and how they work

In previous versions, things like Content Channel, Content Type, and Content Source were part of the category tree. In 3.0, these are descriptive vectors — separate dimensions you can use alongside a main category.

A descriptive vector answers questions like:

• Where is the content published? (Content Channel)
• What is the nature of the content? (Content Type)
• In what format? (Content Media Format)
• What is the origin? (Content Source)
• Where is it from? (Content Source Geo)

Vectors make the taxonomy more flexible — you can mix and match attributes without creating deep, rigid hierarchies.

Example — tagging automotive review content

For the above article reviewing a new convertible sports car:

• Content Categories: Automotive/Convertible (8), Auto Type/Performance Cars (16)
• Content Channel: Editorial/Professional (1001)
• Content Type: Review (1021)
• Content Media Format: Mixed (1026)
• Content Language: en (1068)
• Content Source: Professionally Produced (1215)

With descriptive vectors, your targeting and analytics systems can store and act on each of these dimensions separately.

Taxonomy mapping from 2.2 to 3.0

In addition to moving structural elements into descriptive vectors, IAB reorganized and sometimes removed certain topical categories. Their official Github repository does not contain any mapping between 3.0 and previous versions, so we created one ourselves:

Note: Several News-related categories (e.g., Local News, National News) now map into a broader Politics category, with descriptive vectors used to signal Content Purpose (News, Opinion, Review, etc.).

Key takeaways

• 3.0 is format-aware — it’s the first taxonomy version to explicitly cover CTV, podcasts, games, and mobile apps.
• News got more precise — via descriptive vectors, not just category IDs.
• Some old categories are gone — and need manual remapping.
• Vectors improve flexibility — letting you combine attributes without deep category nesting.

IAB Content Taxonomy 3.0 is not just a list of topics — it’s a multidimensional framework. If you treat categories and descriptive vectors as equally important, you’ll gain richer targeting, better analytics, and more future-proof contextual strategies.