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IAB V1 – 2 tiers - 372 categories
IAB V2 – 4 tiers - 698 categories
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For example, Verity analysis of an article on “The Rise of Alternative Venture Capital” identifies IAB v1.0 categories in 2 tiers, and IAB v2.0 categories in 4 tiers.
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Event Categories
GumGum Events offer hundreds of categories that add another layer of targeting on top of the IAB standard categories and provide more granularity. For example, IAB v2 offers a single category for “National & Civic Holidays”, while GumGum covers content about specific holidays, like “Thanksgiving” and “Christmas.”
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