Content.cat

Content categories describing this piece of content, as taxonomy IDs in the scheme named by Content.cattax. IAB Content Category Taxonomy 1.0 is assumed when no taxonomy is declared.

Currentstring arrayOptionalSince 2.0

Field facts

Path: app.content.cat, dooh.content.cat, site.content.cat
Object: Content
Type: string array
Requirement: Optional
Added: OpenRTB 2.0
Spec section: 3.2.16

How it is used

These categories describe the specific video, episode, or article, and can differ from Site.cat or App.cat. For genre, prefer Content.genres, which has its own taxonomy field. The 2.3 to 2.5 texts described this field as categories of the content producer, a wording error that 2.6 corrected.

Example

Where the field sits in a payload, with everything else left out:

{
  "id": "req-1",
  "app": {
    "content": {
      "cat": [
        "IAB1-7"
      ]
    }
  }
}

Common mistakes

Sending Content Taxonomy 2.x or 3.x IDs without setting Content.cattax, so buyers look them up in the 1.0 list.

Version history

Added in OpenRTB 2.0, and present in the latest snapshot. The table shows how each version's spec text types the field.

Versions	Type in the spec	Required	Deprecated
2.0 to 2.1	array of string	No	No
2.2	array of ings Se	No	No
2.3 to 2.3.1	string array	No	No
2.4	string array	No	No
2.5 to 2.6-202606	string array	No	No