> For the complete documentation index, see [llms.txt](https://docs.exads.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.exads.com/rtb/advertisers/open-rtb/open-rtb-advertisers-response-2p5.md).
# Prebid / OpenRTB 2.5 Bid Response
***
{% hint style="info" %}
**Note**: The Prebid / OpenRTB 2.5 Bid Response will work with both Prebid and standard OpenRTB 2.5. You can read more about Prebid Server [here](https://docs.prebid.org/prebid-server/endpoints/openrtb2/pbs-endpoint-auction.html).
{% endhint %}
***
The response for a bid request has the following structure:
## Bid Response Object
| Attribute | Required? | Description |
| --------- | --------- | ------------------------------------------------------------------- |
| id | Yes | ID of the bid request, must match id sent in the request (string) |
| seatbid | Yes | Collection of bids made by the bidder on behalf of a specific seat. |
### seatbid
| Attribute | Required? | Description |
| --------- | --------- | ------------------------------------------------------------------------------------------------- |
| bid | Yes | ID of the impression object to which this bid applies, must match id sent in the request (string) |
### seatbid.bid
| Attribute | Required? | Description |
| --------- | --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| id | Yes | ID for the bid object chosen by the bidder (string) |
| impid | Yes | ID of the impression object to which this bid applies (string) |
| price | Yes | Bid price in CPM or CPC (float) |
| adm | Yes | Ad markup (string) |
| nurl | No | Win notification URL, it is recommended to use HTTP over HTTPS for nurl (string) - not mandatory |
| burl | No | Billing notification URL, called by EXADS when the impression or click becomes billable (CPM or CPC, per the `btype` field), so it can be counted from the billable event instead of the pixel. Recommended to use HTTP over HTTPS for burl (string) |
| ext | No | EXADS specific extension (object) |
### seatbid.bid.ext
| Attribute | Required? | Description |
| --------- | ----------- | --------------------------------------------------------------------------------------------------------------------------------------- |
| btype | Recommended | Pricing Model. Values: 1 = CPM, 2 = CPC. Default = 1 (int). **Note**: When response is for an Email Clicks zone request, 1 = Smart CPC. |
## JSON Examples
### Banner (Stored Request): JSON
```json
{
"id": "c1218af9-65fc-4d55-9ad6-8795c2daad25",
"seatbid": [
{
"bid": [
{
"id": "7565485375107751077",
"impid": "some-impression-id",
"price": 17.076291896620397,
"adm":"![](\"https://stagingva.rubicon.com:8443/image/300x250.jpg\")
",
"adid": "266959495",
"adomain": [
"https://www.tudublin.ie"
],
"iurl": "https://fra1-ib.adnxs.com/cr?id=266959495",
"cid": "1212",
"crid": "266959495",
"w": 300,
"h": 250,
"ext": {
"prebid": {
"targeting": {
"hb_bidder": "asqClassic",
"hb_bidder_asqClassic": "asqClassic",
"hb_pb": "17.00",
"hb_pb_asqClassic": "17.00",
"hb_size": "300x250",
"hb_size_asqClassic": "300x250"
},
"type": "banner",
"video": {
"duration": 0,
"primary_category": ""
}
},
"bidder": {
"appnexus": {
"brand_id": 791377,
"auction_id": 3048506780519985986,
"bidder_id": 101,
"bid_ad_type": 0
}
}
}
}
],
"seat": "asqClassic"
},
{
"bid": [
{
"id": "613673EF-A07C-4486-8EE9-3FC71A7DC73D",
"impid": "some-impression-id",
"price": 3.2940788932,
"adm": "![](\"https://stagingva.pubmatic.com:8443/image/336x280.jpg\")
",
"adomain": [
"www.addomain.com"
],
"iurl": "http://localhost11",
"crid": "FP_336x280_00",
"w": 336,
"h": 280,
"ext": {
"prebid": {
"targeting": {
"hb_bidder_pubmatic": "pubmatic",
"hb_pb_pubmatic": "3.25",
"hb_size_pubmatic": "336x280"
},
"type": "banner",
"video": {
"duration": 0,
"primary_category": ""
}
},
"bidder": {
"dspid": 6,
"BidType": 0
}
}
}
],
"seat": "pubmatic"
}
],
"cur": "EUR"
}
```
## ADM Examples
The examples below shows example of the HTML used in this ADM parameter.
### Banner: HTML
```xml
```
## No Bid Response
To answer a bid request without making an actual bid, an HTTP response code 204 "No Content" should be sent.
## Billing Notification
If the parameter **Bid Response Object -> Seat Bid Object -> Bid Object -> burl** is in the bid response and is a valid URL, EXADS will send a GET request to it when the impression or click becomes billable (CPM or CPC, per the `btype` field). This allows the event to be counted from the billable server-to-server event rather than from pixel-based tracking.
If both `nurl` and `burl` are present, both will be called.
---
# Agent Instructions
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## Querying This Documentation
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Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://docs.exads.com/rtb/advertisers/open-rtb/open-rtb-advertisers-response-2p5.md?ask=&goal=
```
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