Bid.cattax

The taxonomy used for Bid.cat, as a value from the AdCOM Category Taxonomies list. Defaults to 1, IAB Content Category Taxonomy 1.0. Added in 2.6.

CurrentintegerOptionalSince 2.6-202204

Field facts

Path: seatbid.bid.cattax
Object: Bid
Type: integer
Default: 1
Requirement: Optional
Added: OpenRTB 2.6-202204
Values: AdCOM list Category Taxonomies
Spec section: 4.2.3

How it is used

Use the taxonomy the request named in BidRequest.cattax where you can, so the exchange can compare your categories with its block or allow list without translating them.

Allowed values

Value	Meaning
`1`	IAB Tech Lab Content Category Taxonomy 1.0: The original IAB content categories with codes like IAB1-1; deprecated, but still the default when `cattax` is omitted.
`2`	IAB Tech Lab Content Category Taxonomy 2.0: Content Taxonomy 2.0, the first version with numeric IDs; deprecated in favor of later releases.
`3`	IAB Tech Lab Ad Product Taxonomy 1.0: Categories for the product or service an ad promotes, used for ad blocking and creative labeling.
`4`	IAB Tech Lab Audience Taxonomy 1.1: Audience Taxonomy 1.1, which describes people (demographics, interests, purchase intent) rather than content or ads.
`5`	IAB Tech Lab Content Taxonomy 2.1: Content Taxonomy 2.1, a 2.x revision suitable for content classification.
`6`	IAB Tech Lab Content Taxonomy 2.2: Content Taxonomy 2.2, the newest 2.x version in this list.
`7`	IAB Tech Lab Content Taxonomy 3.0: Content Taxonomy 3.0, the first release of the 3.x generation.
`8`	IAB Tech Lab Ad Product Taxonomy 2.0: Ad Product Taxonomy 2.0, the newer of the two ad product versions in this list.
`9`	IAB Tech Lab Content Taxonomy 3.1: Content Taxonomy 3.1, also the default taxonomy for `Content.genres` when `Content.gtax` is absent.
`500+`	Vendor-specific codes: Vendor-specific taxonomies, such as an exchange's own category codes, agreed between the parties.

Example

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

{
  "seatbid": [
    {
      "bid": [
        {
          "cattax": 1
        }
      ]
    }
  ]
}

Version history

Added in OpenRTB 2.6-202204, 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
2.6-202204	Added in the first 2.6 release, published without a structured text archive; the 2.6-202210 republication is the first tagged text.
2.6-202210 to 2.6-202303	integer, default 1	No	No
2.6-202309 to 2.6-202606	integer, default 1	No	No

Related fields

Other Bid fields

For a walkthrough of the whole object, read Bid response anatomy.