Bid Request

Our OpenRTB bidding API facilitates real-time bidding. Data for bid requests is sent in JSON RFC 4627 format and all fields are considered case-sensitive.

HTTP Headers

Our OpenRTB bidding API uses HTTP 1.1 protocol and sends the following request headers:

Attribute Scope Description
Connection Required The connection type for the request; we accept "Keep-Alive".
Content-Length Required The size of the request.
Content-Type Required The content type for the request. This value is always "application/json".
Host Required The domain of the bidding URL.
x-openrtb-version Required The version of OpenRTB protocol used for the request. The default value is "2.5".

Bid Request Object

The top level bid request object and accompanying fields are below, followed by each lower level object contained within it.

Field Type Description
id String; required IX’s unique ID for the request (alphanumeric).
imp Object; required The Impression Object; contains at least one Banner Object or Video Object.
device Object; required The Device Object.
tmax Integer; optional

Maximum time in milliseconds IX allows to receive bids. To avoid timeouts, the tmax field does not subtract internet latency between IX and the DSP.

Note: If required, we can subtract latency when passing tmax. For more information, please contact your IX Representative.

ext Object; required A custom IX Request Extension Object that contains additional information about the bid request.
app Object; optional The App Object; included if the impression originates from an application.
bcat Array of Strings; optional An array of blocked advertiser categories, based on standard IAB content categories. The full list is available in section 5.1 of the OpenRTB Specification (version 2.5).
regs Object; optional The Regulations Object.
site Object; optional The Site Object; included if the impression originates from a website.
user Object; optional The User Object.

Source Object

Payment ID Chain

Field Type Description
pchain String; optional

Payment ID chain string provides visibility into an impression's supply path. For bid requests sourced directly from IX, the pchain field will display our TAG ID (50b1c356f2c5c8fc) and publisher ID (e.g. 2167).


For example, 50b1c356f2c5c8fc:2167. For bid requests sourced from a supplier, the pchain field will display the TAG ID and publisher ID for both the supplier and IX.


For example, <Supplier ID>:<Publisher ID>-50b1c356f2c5c8fc:2167. For more information or to get a list of supplier IDs for pchain, contact TAG at

Source Ext

Field Type Description
schain Object; optional

Like pchain, schain also provides buyers visibility into all parties who are involved in the selling or reselling of a bid request.

Note: To interpret the schain object, you can reference our sellers.json file that contains a list of all our supply partners at

Schain Object

Field Type Description
complete Integer; required

Flag indicates whether the chain contains all nodes involved in the transaction leading back to the supply source of the inventory.

0 = No

1 = Yes

nodes Object array; required

An array of SupplyChainNode objects in the order of the chain. Each node represents a different seller or exchange system that has touched the impression. The last node in the array represents the seller sending the bid request.

SupplyChainNode Objects

Field Type Description
asi String; required

Domain name of the system that the bidder connects to (e.g. SSP, exchange).

Note: You can find the sellers.json file for each node through this domain name. The same domain is also used in ads.txt files for publishers (e.g.

pid String; required

The seller or reseller account ID.

Note: We will be ending support for the pid field on February 21, 2020. You can find the same information from sid (see below) and

rid String; optional

The request's OpenRTB RequestId issued by the seller.

Note: The same information can also be found in

sid String; required

The seller or reseller account ID.

Note: The same information can also be found in

hp Integer; required

Indicates whether this node is involved in the flow of payment for the inventory. IX will pass hp if an upstream chain includes it.

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