BidRequest.imp[].video

Video

A video placement, generally expecting a VAST response. The most option-heavy object in the protocol.

Fields

Field	Type	Level	Description
mimes	string[]	required	Supported content MIME types. The only required field.
minduration	integer	recommended	Minimum ad duration in seconds.
maxduration	integer	recommended	Maximum ad duration in seconds.
protocols	integer[]	recommended	Supported video protocols, which determine the VAST versions accepted.
w	integer	recommended	Player width in pixels.
h	integer	recommended	Player height in pixels.
startdelay	integer	recommended	Pre-roll, mid-roll or post-roll positioning.
plcmt	integer	optional	Video placement type, added in 2.6.
linearity	integer	optional	Whether a linear or non-linear ad is required.
skip	integer	optional	1 if the player allows the ad to be skipped.
companionad	object[]	optional	Companion banners available with the video.

Example

{
  "mimes": ["video/mp4"],
  "minduration": 5,
  "maxduration": 30,
  "protocols": [2, 3, 5, 6],
  "w": 640,
  "h": 480,
  "startdelay": 0,
  "skip": 1
}

What matters in practice

The protocols array is the field to check when a VAST tag is rejected without an obvious reason: it enumerates which VAST versions the player will accept, and a 4.x response sent where only 2.0 and 3.0 are listed will be discarded. OpenRTB 2.6 also added plcmt to replace the widely misused older placement field, so during the transition the same inventory can be described differently by different exchanges — worth confirming which one a partner populates before building targeting on it.

Related objects

Field names, types and requirement levels from the IAB Tech Lab OpenRTB 2.6 specification (2.6-202211), verified 30 July 2026. The practice notes are not spec text.