Bid.lurl

The loss notice URL, which the exchange calls when it knows this bid lost. Added in 2.5. Exchange policy may rule out loss notices or withhold the clearing price from them.

CurrentstringOptionalSince 2.5

Field facts

Path: seatbid.bid.lurl
Object: Bid
Type: string
Requirement: Optional
Added: OpenRTB 2.5
Spec section: 4.2.3

How it is used

Include ${AUCTION_LOSS} to receive a loss reason code, and ${AUCTION_MIN_TO_WIN} if you want the price that would have won. Where an exchange withholds prices, price macros arrive as empty strings, so the receiving endpoint must accept blanks.

Example

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

{
  "seatbid": [
    {
      "bid": [
        {
          "lurl": "https://loss.dsp.example/l?auction=${AUCTION_ID}&reason=${AUCTION_LOSS}"
        }
      ]
    }
  ]
}

Common mistakes

A loss URL without ${AUCTION_LOSS}, which tells the bidder it lost but not why (openrtb.bid.loss_macro_missing).
Expecting a loss notice for every lost bid. Support and policy vary by exchange.

Version history

Added in OpenRTB 2.5, 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
2.5 to 2.6-202606	string	No	No

Related fields

Other Bid fields

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