Common Ad Transport Standard (CATS)

CATS 1.0

CATS 1.0 Release for public comment: March 2020


Standardizing how requests (and responses) are made is key to allow any two entities to “speak” to each other. While OpenRTB exists as a standard for making ad requests in an RTB transaction, there are a number of other scenarios where no standard exists, or a standard based on HTTP GET macros (VAST 4.x for example) exists. Even the VAST4 macro approach has gaps because of the size limitations inherent to HTTP GET requests, and payloads which include CCPA/GDRP consent strings and URLs for brand safety checks.

CATS aims to address these gap by defining an ad request standard that can be used for any non-RTB use case.

Some key points about CATS (more details in the spec) –

  • CATS is built on AdCOM and HTTP POST requests, which allows for a larger payload to be delivered
  • CATS is similar to OpenRTB 3.0 in many ways – without the “bidding” components.
  • The shared AdCOM foundation also allows companies to share their implementations with OpenRTB
  • As of 1.0, no response format has been mandated. We expect the initial use of CATS to be for video, and the response to be VAST XML.

Read the Press Release

Developed by the Digital Video Technical Standards Working Group

IAB Tech Lab Contact

Amit Shetty
Senior Director, Product Management