Real Time Bidding (RTB) Project
OpenRTB API Specification Version 2.5
FINAL
December 2016

© 2016 IAB Technology Laboratory

OpenRTB API Specification Version 2.5

IAB Tech Lab

Introduction
The RTB Project, formerly known as the OpenRTB Consortium, assembled in November 2010 to develop
a new API specification for companies interested in an open protocol for the automated trading ofdigital media across a broader range of platforms, devices, and advertising solutions. This document is
OpenRTB version 2.5 released in November of 2016; this is the culmination of the working group efforts
and can be found at: http://www.iab.com/openrtb

About the IAB Technology Lab
The IAB Technology Laboratory is a nonprofit research and development consortium charged withproducing and helping companies implement global industry technical standards and solutions. The
goal of the Tech Lab is to reduce friction associated with the digital advertising and marketing supply
chain while contributing to the safe growth of an industry.
The IAB Tech Lab spearheads the development of technical standards, creates and maintains a code
library to assist in rapid, cost-effective implementation of IAB standards, and establishes a test platform
for companies to evaluate the compatibility of their technology solutions with IAB standards, which for
18 years have been the foundation for interoperability and profitable growth in the digital advertising
supply chain.
The OpenRTB Work Group is a working group within the IAB Technology Lab. Further details about the
IAB Technology Lab can be found at: https://iabtechlab.com/

IAB Contact Information
Jennifer Derke
Senior Manager, Product
IAB Technology Lab
openRTB@iab.com

OpenRTB Co-Chairs
Dr. Bill Simmons
CTO – DataXu
OpenRTB Founder
Dr. Jim Butler
VP Engineering, Publisher Platforms – AOL
OpenRTB Specification Author
Dr. Neal Richter
Founder, Principal – Hebbian Labs

LicenseOpenRTB Specification by OpenRTB is licensed under a Creative Commons Attribution 3.0 License. Toview a copy of this license, visit creativecommons.org/licenses/by/3.0/ or write to Creative Commons,
171 Second Street, Suite 300, San Francisco, CA 94105, USA.

Page ii

OpenRTB API Specification Version 2.5

IAB Tech Lab

Table of Contents
Getting Started ...................................................................................................................... 1
1. Introduction .................................................................................................................... 2
1.1
1.2
1.3
1.4
1.5

Mission / Overview ........................................................................................................................................... 2
History of OpenRTB .......................................................................................................................................... 2
Version History ................................................................................................................................................... 3
Resources .............................................................................................................................................................. 3
Terminology......................................................................................................................................................... 3

2. OpenRTB Basics ............................................................................................................... 4
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8

Transport .............................................................................................................................................................. 4
Security .................................................................................................................................................................. 5
Data Format ......................................................................................................................................................... 5
Data Encoding ..................................................................................................................................................... 5
OpenRTB Version HTTP Header.................................................................................................................. 6
Privacy by Design............................................................................................................................................... 7
Relationship to Inventory Quality Guidelines ........................................................................................ 7
Customization and Extensions ..................................................................................................................... 7

3. Bid Request Specification ................................................................................................. 8
3.1
3.2

Object Model ........................................................................................................................................................ 8
Object Specifications ...................................................................................................................................... 10
3.2.1
Object: BidRequest ................................................................................................................................. 10
3.2.2
Object: Source .......................................................................................................................................... 11
3.2.3
Object: Regs............................................................................................................................................... 12
3.2.4
Object: Imp ................................................................................................................................................ 12
3.2.5
Object: Metric ........................................................................................................................................... 13
3.2.6
Object: Banner ......................................................................................................................................... 14
3.2.7
Object: Video ............................................................................................................................................. 15
3.2.8
Object: Audio ............................................................................................................................................ 17
3.2.9
Object: Native........................................................................................................................................... 18
3.2.10 Object: Format ......................................................................................................................................... 18
3.2.11 Object: Pmp ............................................................................................................................................... 19
3.2.12 Object: Deal ............................................................................................................................................... 19
3.2.13 Object: Site................................................................................................................................................. 20
3.2.14 Object: App ................................................................................................................................................ 20
3.2.15 Object: Publisher..................................................................................................................................... 21
3.2.16 Object: Content ........................................................................................................................................ 21
3.2.17 Object: Producer ..................................................................................................................................... 22
3.2.18 Object: Device ........................................................................................................................................... 23
3.2.19 Object: Geo ................................................................................................................................................. 24
3.2.20 Object: User ............................................................................................................................................... 25
3.2.21 Object: Data .............................................................................................................................................. 26
3.2.22 Object: Segment ...................................................................................................................................... 26

4. Bid Response Specification ............................................................................................. 27
4.1
4.2

Object Model ...................................................................................................................................................... 27
Object Specifications ...................................................................................................................................... 28
4.2.1
Object: BidResponse .............................................................................................................................. 28

Page iii

OpenRTB API Specification Version 2.5

4.3

4.4

IAB Tech Lab

4.2.2
Object: SeatBid ........................................................................................................................................ 29
4.2.3
Object: Bid.................................................................................................................................................. 29
Ad Serving Options .......................................................................................................................................... 31
4.3.1
Markup Served on the Win Notice.................................................................................................. 31
4.3.2
Markup Served in the Bid ................................................................................................................... 31
4.3.3
Comparison of Ad Serving Approaches ........................................................................................ 31
Substitution Macros ........................................................................................................................................ 32

5. Enumerated Lists Specification ....................................................................................... 34
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
5.10
5.11
5.12
5.13
5.14
5.15
5.16
5.17
5.18
5.19
5.20
5.21
5.22
5.23
5.24
5.25

Content Categories .......................................................................................................................................... 34
Banner Ad Types .............................................................................................................................................. 45
Creative Attributes .......................................................................................................................................... 45
Ad Position.......................................................................................................................................................... 45
Expandable Direction ..................................................................................................................................... 46
API Frameworks............................................................................................................................................... 46
Video Linearity.................................................................................................................................................. 47
Protocols.............................................................................................................................................................. 47
Video Placement Types ................................................................................................................................. 47
Playback Methods ............................................................................................................................................ 48
Playback Cessation Modes ........................................................................................................................... 48
Start Delay .......................................................................................................................................................... 48
Production Quality .......................................................................................................................................... 49
Companion Types ............................................................................................................................................ 49
Content Delivery Methods............................................................................................................................ 49
Feed Types .......................................................................................................................................................... 50
Volume Normalization Modes .................................................................................................................... 50
Content Context ................................................................................................................................................ 50
IQG Media Ratings ........................................................................................................................................... 50
Location Type .................................................................................................................................................... 51
Device Type ........................................................................................................................................................ 51
Connection Type .............................................................................................................................................. 51
IP Location Services ........................................................................................................................................ 52
No-Bid Reason Codes ..................................................................................................................................... 52
Loss Reason Codes .......................................................................................................................................... 52

6. Bid Request/Response Samples ..................................................................................... 54
6.1
6.2
6.3

6.4

GitHub Repository ........................................................................................................................................... 54
Validator .............................................................................................................................................................. 54
Bid Requests ...................................................................................................................................................... 54
6.3.1
Example 1 – Simple Banner............................................................................................................... 54
6.3.2
Example 2 – Expandable Creative .................................................................................................. 55
6.3.3
Example 3 – Mobile ............................................................................................................................... 56
6.3.4
Example 4 – Video .................................................................................................................................. 57
6.3.5
Example 5 – PMP with Direct Deal ................................................................................................ 59
6.3.6
Example 6 – Native Ad ......................................................................................................................... 60
Bid Responses ................................................................................................................................................... 61
6.4.1
Example 1 – Ad Served on Win Notice.......................................................................................... 61
6.4.2
Example 2 – VAST XML Document Returned Inline ............................................................... 61
6.4.3
Example 3 – Direct Deal Ad Served on Win Notice................................................................. 62
6.4.4
Example 4 – Native Markup Returned Inline ............................................................................ 63

Page iv

OpenRTB API Specification Version 2.5

IAB Tech Lab

7. Implementation Notes ................................................................................................... 64
7.1
7.2
7.3
7.4
7.5

No-Bid Signaling ............................................................................................................................................... 64
Impression Expiration ................................................................................................................................... 65
PMP & Direct Deals ......................................................................................................................................... 66
Skippability......................................................................................................................................................... 69
COPPA Regulation Flag .................................................................................................................................. 71

Appendix A. Additional Information .................................................................................. 73
Appendix B. Specification Change Log ............................................................................... 74

Page v

OpenRTB API Specification Version 2.5

IAB Technology Lab

Getting Started
This specification contains a detailed explanation of an RTB (Real-Time Bidding) interface. Not all
objects are required, and each object may contain a number of optional parameters. To assist a firsttime reader of the specification, we have indicated which fields are essential to support a minimum
viable real time bidding interface for various scenarios (banner, video, etc.).
A minimal viable interface should include the required and recommended parameters, but the scope forthese parameters may be limited to specific scenarios. In these cases, the Description column may
further qualify their required or recommended status. Optional parameters may be included to ensure
maximum value is derived by the parties.
Attribute

Type

Description

Examples of required attributes.

idstring; required...

Grouped at the tops of tables
for convenience.

imp

object array;required...

Examples of recommended
attributes.

site

object;recommended...

Grouped after required
attributes.

app

object;recommended...

deviceobject;recommended

...

user

object;recommended...

Examples of optional attributes,
with and without defaults.

test

integer;default 0...

Attributes are assumed optional
unless explicitly qualified as
required or recommended.

atinteger;default 2

...

tmax

integer

...

wseat

string array...

Figure 1: Example of how Required, Recommended, and Optional attributes are presented.

IMPORTANT: Since recommended attributes are not required, they may not be available from all
supply sources. It is suggested that all parties to OpenRTB transaction develop an integration checklist
to identify which attributes the supply side supports in the bid request, and which attributes thedemand side requires for ad decisioning.

www.iab.com/openrtb

Page 1

OpenRTB API Specification Version 2.5

IAB Technology Lab

1. Introduction
1.1

Mission / Overview

The mission of the OpenRTB project is to spur growth in Real-Time Bidding (RTB) marketplaces by
providing open industry standards for communication between buyers of advertising and sellers of
publisher inventory. There are several aspects to these standards including but not limited to the actual
real-time bidding protocol, information taxonomies, offline configuration synchronization, and many
more.
This document specifies a standard for the Real-Time Bidding Interface that has grown out of previous
OpenRTB collaboration on the “block list project” and the “OpenRTB Mobile” project. These protocol
standards aim to simplify the connection between suppliers of publisher inventory (i.e., exchanges,
networks working with publishers, and sell-side platforms) and competitive buyers of that inventory(i.e., bidders, demand side platforms, or networks working with advertisers).
The overall goal of OpenRTB is and has been to create a lingua franca for communicating between
buyers and sellers. The intent is not to regulate exactly how each business operates. As a project, we
aim to make integration between parties easier, so that innovation can happen at a deeper-level at eachof the businesses in the ecosystem.

1.2

History of OpenRTBOpenRTB was launched as a pilot project between three demand-side platforms (DataXu, MediaMath,and Turn) and three sell-side platforms (Admeld, PubMatic, and The Rubicon Project) in November
2010. The first goal was to standardize communication between parties for exchanging block lists.
Version 1.0 of the OpenRTB block list specification was released in December 2010.
After a positive response from the industry, Nexage approached the OpenRTB project with a proposal tocreate an API specification for OpenRTB focusing on the actual real-time bid request/response protocol
and specifically to support mobile advertising. The mobile subcommittee was formed between
companies representing the buy-side (DataXu, Fiksu, and [X+1]) and companies representing the sellside (Nexage, Pubmatic, Smaato, and Jumptap). This project resulted in the OpenRTB Mobile 1.0
specification, which was released in February 2011.
Following the release of the mobile specification, a video subcommittee was formed with video ad
exchanges (BrightRoll and Adap.tv) collaborating with DataXu and ContextWeb to incorporate support
for video. The goal was to incorporate support for display, video, and mobile in one document. Thiseffort resulted in OpenRTB 2.0, which was released as a unified standard in June 2011.
Due to very widespread adoption by the industry, OpenRTB was adopted as an IAB standard in January
2012 with the release of version 2.1. Governance over the technical content of the specification
remains with the OpenRTB community and its governance rules.

www.iab.com/openrtb

Page 2

OpenRTB API Specification Version 2.5

1.3

IAB Technology Lab

Version History

OpenRTB Real-Time Bidding API
2.5
2.4
2.3
2.2
2.1
2.0
1.0

Support for header bidding, billing and loss notifications, Flex Ads, Payment ID, tactic ID,
impression metrics, out-stream video, and many more minor enhancements.
Support for Audio ad units and the largest set of minor to moderate enhancements in v2.x history.
Support for Native ad units and multiple minor enhancements.
New enhancements for private marketplace direct deals, video, mobile, and regulatory signals.
Revisions for IQG compliance, minor enhancements, and corrections.
Combines display, mobile, and video standards into a unified specification.
Original Release of OpenRTB Mobile.

OpenRTB Display Block List Branch
1.2
1.1
1.0

Publisher Preferences API (proposed).
Minor edits to include real-time exchange of creative attributes.
Original Release of OpenRTB block list specifications.

1.4

Resources

OpenRTB GitHub Repository

github.com/openrtb/OpenRTB/

Development Community Mailing List

groups.google.com/group/openrtb-dev

User Community Mailing List

groups.google.com/group/openrtb-user

1.5

Terminology

The following terms are used throughout this document specifically in the context of the OpenRTBInterface and this specification.
Term

Definition

RTB

Bidding for individual impressions in real-time (i.e., while a consumer is waiting).

Exchange

A service that conducts an auction among bidders per impression.

BidderAn entity that competes in real-time auctions to acquire impressions.

Seat

An advertising entity (e.g., advertiser, agency) that wishes to obtain impressions and uses
bidders to act on their behalf; a customer of a bidder and usually the owner of the advertisingbudget.

Publisher

An entity that operates one or more sites.

Site

Ad supported content including web and applications unless otherwise specified.

Deal

A pre-arranged agreement between a Publisher and a Seat to purchase impressions undercertain terms.

www.iab.com/openrtb

Page 3

OpenRTB API Specification Version 2.5

IAB Technology Lab

2. OpenRTB Basics
The following figure illustrates the OpenRTB interactions between an exchange and its bidders. Ad
requests originate at publisher sites or applications. For each inbound ad request, bid requests arebroadcast to bidders, responses are evaluated under prevailing auction rules, and a winner is selected.
The winning bidder is notified of the auction win via a win notice. Ad markup can either be included in
the bid prospectively or in response to the win notice. A separate billing notice is also available toaccommodate varying policies enacted by exchanges which are beyond the scope of the OpenRTB
specification (e.g., billing on device delivery, viewability, etc.). The win notice informs the bidder’spricing algorithms of a success, whereas the billing notice indicates that spend should actually beapplied. A loss notification is also available to inform the bidder of the reason their bid did not win.
The URLs for win, billing, and loss notices and the ad markup itself can contain any of several standard
macros that enable the exchange to communicate critical data to the bidder (e.g., clearing price).

Figure 2: Reference Model - Request Sequence.

This specification focuses on the real-time interactions of bid request and response and the win, billing,
and loss notices. Other interactions (e.g., block list synchronization, traffic control, creative review, etc.)
are candidates for future OpenRTB initiatives or alternate projects.

2.1

Transport

The base protocol between an exchange and its bidders is HTTP. Specifically, HTTP POST is required forbid requests to accommodate greater payloads than HTTP GET and facilitate the use of binary
representations. Win notices may be either POST or GET at the discretion of the exchange.
Calls returning content (e.g., any bid response, a win notice that returns markup) should return HTTP
code 200. Calls returning no content in response to valid requests (e.g., an empty bid response which isone option for indicating no-bid, a win notice that does not return markup) should return HTTP 204.
Invalid calls (e.g., a bid request containing a malformed or corrupt payload) should return HTTP 400 withno content.

www.iab.com/openrtb

Page 4

OpenRTB API Specification Version 2.5

IAB Technology Lab

BEST PRACTICE: One of the simplest and most effective ways of improving connection performance is toenable HTTP Persistent Connections, also known as Keep-Alive. This has a profound impact on overall
performance by reducing connection management overhead as well as CPU utilization on both sides of
the interface.

2.2

Security

HTTPS (i.e., secure HTTP) is not required for OpenRTB compliance. However, there is a growing trend in
the industry to use HTTPS for added security of exchange/bidder communications. It is recommended,
therefore, that exchanges and bidders consider supporting both HTTP and HTTPS.

2.3

Data Format

JSON (JavaScript Object Notation) is the suggested format for bid request and bid response data
payloads. JSON was chosen for its combination of human readability and compactness. The data
payloads are described in Section 3 and Section 4.
Optionally, an exchange may also offer binary representations (e.g., compressed JSON, ProtoBuf, Avro,etc.), which can be more efficient in terms of transmission time and bandwidth. The IAB Tech Lab may
offer reference implementations for these or other formats. When available, the use of these IAB
reference implementations is highly recommended to reduce exchange-specific variations.
The bid request specifies the representation as a mime type using the Content-Type HTTP header. The
mime type for the standard JSON representation is “application/json” as shown. The format of the bid
response must be the same as the bid request.
Content-Type: application/json

If alternative binary representations are used, the exchange or SSP should specify the Content-Typeappropriately. For example: “Content-Type: avro/binary” or “Content-Type: application/x-protobuf”. If
the content-type is missing, the bidder should assume the type is application/json, unless a different
default has been selected by an exchange.
As a convention, the absence of an attribute has a formal meaning. In most cases, this indicates that thevalue is unknown, unless otherwise specified.

2.4

Data Encoding

Compressing data sent between exchanges and bidders can be very beneficial. Compression greatly
reduces the size of data transferred and thus saves network bandwidth for both exchanges andbidders. To realize this savings fully, compression should be enabled for both the bid request sent by
the exchange and the bid response returned by the bidder.
Compression can be enabled on the bid response using standard HTTP 1.1 mechanisms. Most
webservers already support gzip compression of response content and as such it is an ideal choice. For
an exchange to signal they would like the response to be compressed, it should set the standard HTTP
1.1 Accept-Encoding header. The encoding value used should be “gzip”.
www.iab.com/openrtb

Page 5

OpenRTB API Specification Version 2.5

IAB Technology Lab

Accept-Encoding: gzip

This header represents to bidders an indication by the exchange that it is capable of accepting gzip
encoding for the response. If the bidder server supports this and is correctly configured, it willautomatically respond with content that is gzip encoded. This will be indicated using the standard HTTP
1.1 Content-Encoding header.
Content-Encoding: gzip

To enable compression on the bid request, it must first be agreed upon between the exchange and thebidder that this is supported. This is similar to when a custom data format is used since the exchange
has to know both format and encoding before sending the bid request. If the bidder supports it, theexchange should indicate it is sending a gzip compressed bid request by setting the HTTP 1.1 ContentEncoding header. The encoding value used should be “gzip”.
Content-Encoding: gzip

If this header is not set then it is assumed that the request content isn’t encoded. In HTTP 1.1, theContent-Encoding header is usually only used for response content. However by using this header forthe request content as well we are able to indicate a request is compressed regardless of the data
format used. This is useful since even binary data formats can benefit from being compressed.

2.5

OpenRTB Version HTTP Header

The OpenRTB Version should be passed in the header of a bid request with a custom header parameter.
This will allow bidders to recognize the version of the message contained before attempting to parse therequest.
Additionally, it is recommended albeit optional that bidders place an identically formatted message inthe HTTP header of the response with the protocol version the bidder has implemented. The message
may contain a different version number than the request header.
x-openrtb-version: 2.5

This version should be specified as <major>.<minor> (e.g., 2.5). First or second level increments on theversion are changes to the protocol. In general, second-level changes should be backwards compatible,
whereas first level changes need not be backwards compatible. Any third level revisions (such as 2.5.1)
should not change the protocol itself; only descriptions and notes that don’t affect the protocol content.
Third level versions should not be included in this header since they should have no technical impact.

www.iab.com/openrtb

Page 6

OpenRTB API Specification Version 2.5

2.6

IAB Technology Lab

Privacy by Design

The OpenRTB project fully supports privacy policies as specified by buyers and sellers of advertising. In
particular OpenRTB supports do-not-track (Section 3.2.18), COPPA restriction signaling (Section 7.5), andthe ability to pass user preferences from sellers to buyers through the User object (Section 3.2.20).

2.7

Relationship to Inventory Quality Guidelines

OpenRTB is fully compatible with the Inventory Quality Guidelines (IQG) available here:
www.tagtoday.net/iqg. In particular, many of the taxonomies and lists used in this specification are
derived from either the IQG or the IAB Technology Lab.

2.8

Customization and Extensions

The OpenRTB spec allows for exchange specific customization and extensions of the specification. Any
object may contain extensions. In order to keep extension fields consistent across platforms, theyshould consistently be named “ext”.

www.iab.com/openrtb

Page 7

OpenRTB API Specification Version 2.5

IAB Technology Lab

3. Bid Request Specification
RTB transactions are initiated when an exchange or other supply source sends a bid request to a bidder.
The bid request consists of the top-level bid request object, at least one impression object, and may
optionally include additional objects providing impression context.

3.1

Object Model

Following is the object model for the bid request. The top-level object (i.e., in JSON the unnamed outerobject) is denoted as BidRequest in the model. Of its direct subordinates, only Imp is technicallyrequired since it is fundamental to describing the impression being sold and its requires at least one of
Banner (which may allow multiple formats), Video, Audio, and Native to define the type of
impression (i.e., whichever one or more the publisher is willing to accept; although a bid will be forexactly one of those specified). An impression can optionally be subject to a private marketplace.

Figure 3: Bid Request object model.

www.iab.com/openrtb

Page 8

OpenRTB API Specification Version 2.5

IAB Technology Lab

Other subordinates to the BidRequest provide various forms of information to assist bidders in making
targeting and pricing decisions. This includes details about the user, the device they’re using, thelocation of either, regulatory constraints, and the content and media in which the impression will occur.
On the latter, there is the distinction between site (i.e., website) and application (i.e., non-browser app
typically in mobile). The abstract class called DistributionChannel is just a modeling concept toindicate that a BidRequest is related to either a Site or an App, but not both (i.e., a distribution
channel is an abstraction of site and app). Both sites and apps can be further described by data about
their publisher, the content, and the content’s producer.
Not shown in the model figure is an extensions object. This is an object of undefined structure that canbe added to any other object to convey exchange-specific extensions to the standard. Exchanges using
these objects are responsible for publishing their extensions to their bidders.
The following table summarizes the objects in the Bid Request model and serves as an index into thedetailed definitions in the subsections that follow.
ObjectSectionDescription

BidRequest

3.2.1

Top-level object.

Source3.2.2

Request source details on post-auction decisioning (e.g., header bidding).

Regs

3.2.3

Regulatory conditions in effect for all impressions in this bid request.

Imp

3.2.4

Container for the description of a specific impression; at least 1 per request.

Metric

3.2.5

A quantifiable often historical data point about an impression.

Banner

3.2.6

Details for a banner impression (incl. in-banner video) or video companion ad.

Video

3.2.7

Details for a video impression.

Audio

3.2.8

Container for an audio impression.

Native

3.2.9

Container for a native impression conforming to the Dynamic Native Ads API.

Format3.2.10An allowed size of a banner.

Pmp

3.2.11

Collection of private marketplace (PMP) deals applicable to this impression.

Deal

3.2.12

Deal terms pertaining to this impression between a seller and buyer.

Site

3.2.13

Details of the website calling for the impression.

App

3.2.14

Details of the application calling for the impression.

Publisher

3.2.15

Entity that controls the content of and distributes the site or app.

Content

3.2.16

Details about the published content itself, within which the ad will be shown.

Producer

3.2.17

Producer of the content; not necessarily the publisher (e.g., syndication).

Device3.2.18

Details of the device on which the content and impressions are displayed.

Geo

3.2.19Location of the device or user’s home base depending on the parent object.

User

3.2.20

Human user of the device; audience for advertising.

Data

3.2.21

Collection of additional user targeting data from a specific data source.

Segment

3.2.22

Specific data point about a user from a specific data source.

www.iab.com/openrtb

Page 9

OpenRTB API Specification Version 2.5

3.2

IAB Technology Lab

Object Specifications

The subsections that follow define each of the objects in the bid request model. Several conventions
are used throughout:Attributes are “required” if their omission would technically break the protocol.
Some optional attributes are denoted “recommended” due to their elevated business importance.
Unless a default value is explicitly specified, an omitted attribute is interpreted as “unknown”.

3.2.1 Object: BidRequest
The top-level bid request object contains a globally unique bid request or auction ID. This id attribute isrequired as is at least one impression object (Section 3.2.4). Other attributes in this top-level object
establish rules and restrictions that apply to all impressions being offered.
There are also several subordinate objects that provide detailed data to potential buyers. Among these
are the Site and App objects, which describe the type of published media in which the impression(s)appear. These objects are highly recommended, but only one applies to a given bid request dependingon whether the media is browser-based web content or a non-browser application, respectively.
Attribute

Type

Descriptionidstring; required

Unique ID of the bid request, provided by the exchange.

imp

object array;required

Array of Imp objects (Section 3.2.4) representing theimpressions offered. At least 1 Imp object is required.

site

object;recommended

Details via a Site object (Section 3.2.13) about the publisher’s
website. Only applicable and recommended for websites.

app

object;recommended

Details via an App object (Section 3.2.14) about the publisher’sapp (i.e., non-browser applications). Only applicable andrecommended for apps.

deviceobject;recommended

Details via a Device object (Section 3.2.18) about the user’s
device to which the impression will be delivered.

user

object;recommended

Details via a User object (Section 3.2.20) about the humanuser of the device; the advertising audience.

test

integer;default 0

Indicator of test mode in which auctions are not billable,
where 0 = live mode, 1 = test mode.

atinteger;default 2

Auction type, where 1 = First Price, 2 = Second Price Plus.
Exchange-specific auction types can be defined using values
greater than 500.

tmax

integerMaximum time in milliseconds the exchange allows for bids tobe received including Internet latency to avoid timeout. Thisvalue supersedes any a priori guidance from the exchange.

wseat

string array

White list of buyer seats (e.g., advertisers, agencies) allowed
to bid on this impression. IDs of seats and knowledge of thebuyer’s customers to which they refer must be coordinatedbetween bidders and the exchange a priori. At most, only oneof wseat and bseat should be used in the same request.
Omission of both implies no seat restrictions.

www.iab.com/openrtb

Page 10

OpenRTB API Specification Version 2.5

IAB Technology Lab

bseat

string array

Block list of buyer seats (e.g., advertisers, agencies) restrictedfrom bidding on this impression. IDs of seats and knowledgeof the buyer’s customers to which they refer must be
coordinated between bidders and the exchange a priori. At
most, only one of wseat and bseat should be used in thesame request. Omission of both implies no seat restrictions.

allimps

integer;default 0

Flag to indicate if Exchange can verify that the impressions
offered represent all of the impressions available in context(e.g., all on the web page, all video spots such as pre/mid/postroll) to support road-blocking. 0 = no or unknown, 1 = yes, theimpressions offered represent all that are available.

curstring array

Array of allowed currencies for bids on this bid request using
ISO-4217 alpha codes. Recommended only if the exchange
accepts multiple currencies.

wlang

string array

White list of languages for creatives using ISO-639-1-alpha-2.
Omission implies no specific restrictions, but buyers would be
advised to consider language attribute in the Device and/orContent objects if available.

bcat

string array

Blocked advertiser categories using the IAB content
categories. Refer to List 5.1.

badv

string array

Block list of advertisers by their domains (e.g., “ford.com”).

bappstring array

Block list of applications by their platform-specific exchangeindependent application identifiers. On Android, these should
be bundle or package names (e.g., com.foo.mygame). On iOS,these are numeric IDs.

sourceobjectA Sorce object (Section 3.2.2) that provides data about theinventory source and which entity makes the final decision.

regs

objectA Regs object (Section 3.2.3) that specifies any industry, legal,or governmental regulations in force for this request.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.2 Object: SourceThis object describes the nature and behavior of the entity that is the source of the bid request
upstream from the exchange. The primary purpose of this object is to define post-auction or upstream
decisioning when the exchange itself does not control the final decision. A common example of this isheader bidding, but it can also apply to upstream server entities such as another RTB exchange, a
mediation platform, or an ad server combines direct campaigns with 3rd party demand in decisioning.
Attribute

Type

Description

fdInteger;recommended

Entity responsible for the final impression sale decision, where
0 = exchange, 1 = upstream source.

tidstring;recommended

Transaction ID that must be common across all participants inthis bid request (e.g., potentially multiple exchanges).

pchainstring;recommended

Payment ID chain string containing embedded syntax
described in the TAG Payment ID Protocol v1.0.

www.iab.com/openrtb

Page 11

OpenRTB API Specification Version 2.5

ext

objectIAB Technology Lab

Placeholder for exchange-specific extensions to OpenRTB.

3.2.3 Object: Regs
This object contains any legal, governmental, or industry regulations that apply to the request. The
coppa flag signals whether or not the request falls under the United States Federal Trade Commission’s
regulations for the United States Children’s Online Privacy Protection Act (“COPPA”).
Attribute

Type

Description

coppa

integer

Flag indicating if this request is subject to the COPPA
regulations established by the USA FTC, where 0 = no, 1 = yes.
Refer to Section 7.5 for more information.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.4 Object: Imp
This object describes an ad placement or impression being auctioned. A single bid request can include
multiple Imp objects, a use case for which might be an exchange that supports selling all ad positions on
a given page. Each Imp object has a required ID so that bids can reference them individually.
The presence of Banner (Section 3.2.6), Video (Section 3.2.7), and/or Native (Section 3.2.9) objects
subordinate to the Imp object indicates the type of impression being offered. The publisher can choose
one such type which is the typical case or mix them at their discretion. However, any given bid for the
impression must conform to one of the offered types.
Attribute

Type

Descriptionidstring; required

A unique identifier for this impression within the context ofthe bid request (typically, starts with 1 and increments.

metricobject array

An array of Metric object (Section 3.2.5).

bannerobjectA Banner object (Section 3.2.6); required if this impression isoffered as a banner ad opportunity.

video

objectA Video object (Section 3.2.7); required if this impression isoffered as a video ad opportunity.

audio

objectAn Audio object (Section 3.2.8); required if this impression isoffered as an audio ad opportunity.

nativeobjectA Native object (Section 3.2.9); required if this impression isoffered as a native ad opportunity.

pmp

objectA Pmp object (Section 3.2.11) containing any private
marketplace deals in effect for this impression.

displaymanager

stringName of ad mediation partner, SDK technology, or player
responsible for rendering ad (typically video or mobile). Usedby some ad servers to customize ad code by partner.
Recommended for video and/or apps.

www.iab.com/openrtb

Page 12

OpenRTB API Specification Version 2.5

IAB Technology Lab

displaymanagerver

string

Version of ad mediation partner, SDK technology, or player
responsible for rendering ad (typically video or mobile). Usedby some ad servers to customize ad code by partner.
Recommended for video and/or apps.

instl

integer;default 0

1 = the ad is interstitial or full screen, 0 = not interstitial.

tagidstringIdentifier for specific ad placement or ad tag that was used toinitiate the auction. This can be useful for debugging of any
issues, or for optimization by the buyer.

bidfloor

float; default 0

Minimum bid for this impression expressed in CPM.

bidfloorcur

string;default “USD”

Currency specified using ISO-4217 alpha codes. This may bedifferent from bid currency returned by bidder if this isallowed by the exchange.

clickbrowser

integer

Indicates the type of browser opened upon clicking thecreative in an app, where 0 = embedded, 1 = native. Note that
the Safari View Controller in iOS 9.x devices is considered anative browser for purposes of this attribute.

secureinteger

Flag to indicate if the impression requires secure HTTPS URL
creative assets and markup, where 0 = non-secure, 1 = secure.
If omitted, the secure state is unknown, but non-secure HTTP
support can be assumed.

iframebuster

string array

Array of exchange-specific names of supported iframe busters.

exp

integer

Advisory as to the number of seconds that may elapse
between the auction and the actual impression.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.5 Object: MetricThis object is associated with an impression as an array of metrics. These metrics can offer insight into
the impression to assist with decisioning such as average recent viewability, click-through rate, etc. Each
metric is identified by its type, reports the value of the metric, and optionally identifies the source orvendor measuring the value.
Attribute

Type

Description

type

string; required

Type of metric being presented using exchange curated string
names which should be published to bidders a priori.

value

float; required

Number representing the value of the metric. Probabilities
must be in the range 0.0 – 1.0.

vendorstring;recommended

Source of the value using exchange curated string names
which should be published to bidders a priori. If the exchange
itself is the source versus a third party, “EXCHANGE” isrecommended.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

www.iab.com/openrtb

Page 13

OpenRTB API Specification Version 2.5

IAB Technology Lab

3.2.6 Object: BannerThis object represents the most general type of impression. Although the term “banner” may have very
specific meaning in other contexts, here it can be many things including a simple static image, an
expandable ad unit, or even in-banner video (refer to the Video object in Section 3.2.7 for the moregeneralized and full featured video ad units). An array of Banner objects can also appear within theVideo to describe optional companion ads defined in the VAST specification.
The presence of a Banner as a subordinate of the Imp object indicates that this impression is offered asa banner type impression. At the publisher’s discretion, that same impression may also be offered asvideo, audio, and/or native by also including as Imp subordinates objects of those types. However, any
given bid for the impression must conform to one of the offered types.
Attribute

Type

Description

formatobject array;
recommended

Array of format objects (Section 3.2.10) representing thebanner sizes permitted. If none are specified, then use of theh and w attributes is highly recommended.

w

integerExact width in device independent pixels (DIPS);
recommended if no format objects are specified.

hintegerExact height in device independent pixels (DIPS);
recommended if no format objects are specified.

wmax

integer;
DEPRECATED

NOTE: Deprecated in favor of the format array.

integer;
DEPRECATED

NOTE: Deprecated in favor of the format array.

integer;
DEPRECATED

NOTE: Deprecated in favor of the format array.

integer;
DEPRECATED

NOTE: Deprecated in favor of the format array.

btype

integer array

Blocked banner ad types. Refer to List 5.2.

battr

integer array

Blocked creative attributes. Refer to List 5.3.

posinteger

Ad position on screen. Refer to List 5.4.

mimes

string array

Content MIME types supported. Popular MIME types may
include “application/x-shockwave-flash”,“image/jpg”, and “image/gif”.

topframe

integer

Indicates if the banner is in the top frame as opposed to an
iframe, where 0 = no, 1 = yes.

expdirinteger array

Directions in which the banner may expand. Refer to List 5.5.

api

integer array

List of supported API frameworks for this impression. Refer to
List 5.6. If an API is not explicitly listed, it is assumed not to besupported.

hmax
wmin
hmin

www.iab.com/openrtb

Maximum width in device independent pixels (DIPS).
Maximum height in device independent pixels (DIPS).
Minimum width in device independent pixels (DIPS).
Minimum height in device independent pixels (DIPS).

Page 14

OpenRTB API Specification Version 2.5

IAB Technology Lab

idstringUnique identifier for this banner object. Recommended when
Banner objects are used with a Video object (Section 3.2.7) torepresent an array of companion ads. Values usually start at 1
and increase with each object; should be unique within an
impression.

vcm

integer

Relevant only for Banner objects used with a Video object(Section 3.2.7) in an array of companion ads. Indicates thecompanion banner rendering mode relative to the associatedvideo, where 0 = concurrent, 1 = end-card.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.7 Object: Video
This object represents an in-stream video impression. Many of the fields are non-essential for minimally
viable transactions, but are included to offer fine control when needed. Video in OpenRTB generally
assumes compliance with the VAST standard. As such, the notion of companion ads is supported by
optionally including an array of Banner objects (refer to the Banner object in Section 3.2.6) that define
these companion ads.
The presence of a Video as a subordinate of the Imp object indicates that this impression is offered as avideo type impression. At the publisher’s discretion, that same impression may also be offered asbanner, audio, and/or native by also including as Imp subordinates objects of those types. However,any given bid for the impression must conform to one of the offered types.
Attribute

Type

Description

mimes

string array;requiredContent MIME types supported (e.g., “video/x-ms-wmv”,“video/mp4”).

minduration

integer;recommended

Minimum video ad duration in seconds.

maxduration

integer;recommended

Maximum video ad duration in seconds.

protocols

integer array;
recommended

Array of supported video protocols. Refer to List 5.8. At least
one supported protocol must be specified in either the
protocol or protocols attribute.

protocolinteger;
DEPRECATED

NOTE: Deprecated in favor of protocols.

w

integer;recommended

Width of the video player in device independent pixels (DIPS).

hinteger;recommended

Height of the video player in device independent pixels (DIPS).

startdelay

integer;recommended

Indicates the start delay in seconds for pre-roll, mid-roll, or
post-roll ad placements. Refer to List 5.12 for additional
generic values.

placement

integer

Placement type for the impression. Refer to List 5.9.

www.iab.com/openrtb

Supported video protocol. Refer to List 5.8. At least one
supported protocol must be specified in either the protocol
or protocols attribute.

Page 15

OpenRTB API Specification Version 2.5

IAB Technology Lab

linearity

integer

Indicates if the impression must be linear, nonlinear, etc. If
none specified, assume all are allowed. Refer to List 5.7.

skip

integer

Indicates if the player will allow the video to be skipped,
where 0 = no, 1 = yes.
If a bidder sends markup/creative that is itself skippable, theBid object should include the attr array with an element of
16 indicating skippable video. Refer to List 5.3.

skipmininteger;default 0

Videos of total duration greater than this number of seconds
can be skippable; only applicable if the ad is skippable.

skipafter

integer;default 0

Number of seconds a video must play before skipping isenabled; only applicable if the ad is skippable.

sequence

integer

If multiple ad impressions are offered in the same bid request,
the sequence number will allow for the coordinated deliveryof multiple creatives.

battr

integer array

Blocked creative attributes. Refer to List 5.3.

maxextended

integerMaximum extended ad duration if extension is allowed. If
blank or 0, extension is not allowed. If -1, extension isallowed, and there is no time limit imposed. If greater than 0,then the value represents the number of seconds of extended
play supported beyond the maxduration value.

minbitrateinteger

Minimum bit rate in Kbps.

maxbitrateintegerMaximum bit rate in Kbps.

boxingallowed

integer;default 1

Indicates if letter-boxing of 4:3 content into a 16:9 window isallowed, where 0 = no, 1 = yes.

playbackmethod

integer array

Playback methods that may be in use. If none are specified,
any method may be used. Refer to List 5.10. Only one
method is typically used in practice. As a result, this array may
be converted to an integer in a future version of thespecification. It is strongly advised to use only the firstelement of this array in preparation for this change.

playbackend

integer

The event that causes playback to end. Refer to List 5.11.

delivery

integer array

Supported delivery methods (e.g., streaming, progressive). If
none specified, assume all are supported. Refer to List 5.15.

posinteger

Ad position on screen. Refer to List 5.4.

companionad

object array

Array of Banner objects (Section 3.2.6) if companion ads areavailable.

api

integer array

List of supported API frameworks for this impression. Refer to
List 5.6. If an API is not explicitly listed, it is assumed not to besupported.

companiontype

integer array

Supported VAST companion ad types. Refer to List 5.14.
Recommended if companion Banner objects are included via
the companionad array. If one of these banners will berendered as an end-card, this can be specified using the vcm
attribute with the particular banner (Section 3.2.6).

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

www.iab.com/openrtb

Page 16

OpenRTB API Specification Version 2.5

IAB Technology Lab

3.2.8 Object: Audio
This object represents an audio type impression. Many of the fields are non-essential for minimally
viable transactions, but are included to offer fine control when needed. Audio in OpenRTB generally
assumes compliance with the DAAST standard. As such, the notion of companion ads is supported by
optionally including an array of Banner objects (refer to the Banner object in Section 3.2.6) that define
these companion ads.
The presence of a Audio as a subordinate of the Imp object indicates that this impression is offered as
an audio type impression. At the publisher’s discretion, that same impression may also be offered asbanner, video, and/or native by also including as Imp subordinates objects of those types. However, any
given bid for the impression must conform to one of the offered types.
Attribute

Type

Description

mimes

string array;requiredContent MIME types supported (e.g., “audio/mp4”).

minduration

integer;recommended

Minimum audio ad duration in seconds.

maxduration

integer;recommended

Maximum audio ad duration in seconds.

protocols

integer array;
recommended

Array of supported audio protocols. Refer to List 5.8.

startdelay

integer;recommended

Indicates the start delay in seconds for pre-roll, mid-roll, or
post-roll ad placements. Refer to List 5.12.

sequence

integer

If multiple ad impressions are offered in the same bid request,
the sequence number will allow for the coordinated deliveryof multiple creatives.

battr

integer array

Blocked creative attributes. Refer to List 5.3.

maxextended

integerMaximum extended ad duration if extension is allowed. If
blank or 0, extension is not allowed. If -1, extension isallowed, and there is no time limit imposed. If greater than 0,then the value represents the number of seconds of extended
play supported beyond the maxduration value.

minbitrateinteger

Minimum bit rate in Kbps.

maxbitrateintegerMaximum bit rate in Kbps.

delivery

integer array

Supported delivery methods (e.g., streaming, progressive). If
none specified, assume all are supported. Refer to List 5.15.

companionad

object array

Array of Banner objects (Section 3.2.6) if companion ads areavailable.

api

integer array

List of supported API frameworks for this impression. Refer to
List 5.6. If an API is not explicitly listed, it is assumed not to besupported.

companiontype

integer array

Supported DAAST companion ad types. Refer to List 5.14.
Recommended if companion Banner objects are included via
the companionad array.

maxseqinteger

The maximum number of ads that can be played in an ad pod.

www.iab.com/openrtb

Page 17

OpenRTB API Specification Version 2.5

IAB Technology Lab

feed

integer

Type of audio feed. Refer to List 5.16.

stitched

integer

Indicates if the ad is stitched with audio content or delivered
independently, where 0 = no, 1 = yes.

nvol

integer

Volume normalization mode. Refer to List 5.17.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.9 Object: Native
This object represents a native type impression. Native ad units are intended to blend seamlessly into
the surrounding content (e.g., a sponsored Twitter or Facebook post). As such, the response must be
well-structured to afford the publisher fine-grained control over rendering.
The Native Subcommittee has developed a companion specification to OpenRTB called the Dynamic
Native Ads API. It defines the request parameters and response markup structure of native ad units.
This object provides the means of transporting request parameters as an opaque string so that the
specific parameters can evolve separately under the auspices of the Dynamic Native Ads API. Similarly,
the ad markup served will be structured according to that specification.
The presence of a Native as a subordinate of the Imp object indicates that this impression is offered asa native type impression. At the publisher’s discretion, that same impression may also be offered asbanner, video, and/or audio by also including as Imp subordinates objects of those types. However, any
given bid for the impression must conform to one of the offered types.
Attribute

Type

Description

requeststring; required

Request payload complying with the Native Ad Specification.

verstring;recommended

Version of the Dynamic Native Ads API to which request
complies; highly recommended for efficient parsing.

api

integer array

List of supported API frameworks for this impression. Refer to
List 5.6. If an API is not explicitly listed, it is assumed not to besupported.

battr

integer array

Blocked creative attributes. Refer to List 5.3.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.10 Object: Format
This object represents an allowed size (i.e., height and width combination) or Flex Ad parameters for abanner impression. These are typically used in an array where multiple sizes are permitted. It is
recommended that either the w/h pair or the wratio/hratio/wmin set (i.e., for Flex Ads) be specified.
Attribute

Type

Descriptionw

integer

Width in device independent pixels (DIPS).

hinteger

Height in device independent pixels (DIPS).

wratiointeger

Relative width when expressing size as a ratio.

hratiointeger

Relative height when expressing size as a ratio.

www.iab.com/openrtb

Page 18

OpenRTB API Specification Version 2.5

IAB Technology Lab

wmin

integer

The minimum width in device independent pixels (DIPS) at
which the ad will be displayed the size is expressed as a ratio.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.11 Object: Pmp
This object is the private marketplace container for direct deals between buyers and sellers that may
pertain to this impression. The actual deals are represented as a collection of Deal objects. Refer to
Section 7.3 for more details.
Attribute

Type

Description

private_auction

integer;default 0

Indicator of auction eligibility to seats named in the Direct
Deals object, where 0 = all bids are accepted, 1 = bids are
restricted to the deals specified and the terms thereof.

deals

object array

Array of Deal (Section 3.2.12) objects that convey the specificdeals applicable to this impression.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.12 Object: Deal
This object constitutes a specific deal that was struck a priori between a buyer and a seller. Its presencewith the Pmp collection indicates that this impression is available under the terms of that deal. Refer to
Section 7.3 for more details.
Attribute

Type

Descriptionidstring; required

A unique identifier for the direct deal.

bidfloor

float; default 0

Minimum bid for this impression expressed in CPM.

bidfloorcur

string;default ”USD”

Currency specified using ISO-4217 alpha codes. This may bedifferent from bid currency returned by bidder if this isallowed by the exchange.

atinteger

Optional override of the overall auction type of the bid
request, where 1 = First Price, 2 = Second Price Plus, 3 = thevalue passed in bidfloor is the agreed upon deal price.
Additional auction types can be defined by the exchange.

wseat

string array

Whitelist of buyer seats (e.g., advertisers, agencies) allowed tobid on this deal. IDs of seats and the buyer’s customers towhich they refer must be coordinated between bidders andthe exchange a priori. Omission implies no seat restrictions.

wadomainstring array

Array of advertiser domains (e.g., advertiser.com) allowed tobid on this deal. Omission implies no advertiser restrictions.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

www.iab.com/openrtb

Page 19

OpenRTB API Specification Version 2.5

IAB Technology Lab

3.2.13 Object: Site
This object should be included if the ad supported content is a website as opposed to a non-browser
application. A bid request must not contain both a Site and an App object. At a minimum, it is usefulto provide a site ID or page URL, but this is not strictly required.
Attribute

Type

Descriptionidstring;recommended

Exchange-specific site ID.

namestringSite name (may be aliased at the publisher’s request).

domainstring

Domain of the site (e.g., “mysite.foo.com”).

catstring array

Array of IAB content categories of the site. Refer to List 5.1.

sectioncat

string array

Array of IAB content categories that describe the current
section of the site. Refer to List 5.1.

pagecatstring array

Array of IAB content categories that describe the current pageor view of the site. Refer to List 5.1.

pagestring

URL of the page where the impression will be shown.

refstringReferrer URL that caused navigation to the current page.

searchstringSearch string that caused navigation to the current page.

mobileinteger

Indicates if the site has been programmed to optimize layout
when viewed on mobile devices, where 0 = no, 1 = yes.

privacypolicy

integer

Indicates if the site has a privacy policy, where 0 = no, 1 = yes.

publisher

objectDetails about the Publisher (Section 3.2.15) of the site.

content

objectDetails about the Content (Section 3.2.16) within the site.

keywords

stringComma separated list of keywords about the site.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.14 Object: App
This object should be included if the ad supported content is a non-browser application (typically inmobile) as opposed to a website. A bid request must not contain both an App and a Site object. At aminimum, it is useful to provide an App ID or bundle, but this is not strictly required.
Attribute

Type

Descriptionidstring;recommended

Exchange-specific app ID.

namestring

App name (may be aliased at the publisher’s request).

bundlestringA platform-specific application identifier intended to be
unique to the app and independent of the exchange. On
Android, this should be a bundle or package name (e.g.,com.foo.mygame). On iOS, it is typically a numeric ID.

domainstring

Domain of the app (e.g., “mygame.foo.com”).

storeurl

stringApp store URL for an installed app; for IQG 2.1 compliance.

www.iab.com/openrtb

Page 20

OpenRTB API Specification Version 2.5

IAB Technology Lab

cat

string array

Array of IAB content categories of the app. Refer to List 5.1.

sectioncat

string array

Array of IAB content categories that describe the current
section of the app. Refer to List 5.1.

pagecatstring array

Array of IAB content categories that describe the current pageor view of the app. Refer to List 5.1.

verstringApplication version.

privacypolicy

integer

Indicates if the app has a privacy policy, where 0 = no, 1 = yes.

paid

integer

0 = app is free, 1 = the app is a paid version.

publisher

objectDetails about the Publisher (Section 3.2.15) of the app.

content

objectDetails about the Content (Section 3.2.16) within the app.

keywords

stringComma separated list of keywords about the app.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.15 Object: Publisher
This object describes the publisher of the media in which the ad will be displayed. The publisher istypically the seller in an OpenRTB transaction.
Attribute

Type

DescriptionidstringExchange-specific publisher ID.

namestringPublisher name (may be aliased at the publisher’s request).

catstring array

Array of IAB content categories that describe the publisher.
Refer to List 5.1.

domainstringHighest level domain of the publisher (e.g., “publisher.com”).

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.16 Object: Content
This object describes the content in which the impression will appear, which may be syndicated or nonsyndicated content. This object may be useful when syndicated content contains impressions and does
not necessarily match the publisher’s general content. The exchange might or might not haveknowledge of the page where the content is running, as a result of the syndication method. For
example might be a video impression embedded in an iframe on an unknown web property or device.
Attribute

Type

DescriptionidstringID uniquely identifying the content.

episodeinteger

Episode number.

title

stringContent title.
Video Examples: “Search Committee” (television), “A New
Hope” (movie), or “Endgame” (made for web).
Non-Video Example: “Why an Antarctic Glacier Is Melting So
Quickly” (Time magazine article).

www.iab.com/openrtb

Page 21

OpenRTB API Specification Version 2.5

seriesstring

IAB Technology Lab

Content series.
Video Examples: “The Office” (television), “Star Wars” (movie),or “Arby ‘N’ The Chief” (made for web).
Non-Video Example: “Ecocentric” (Time Magazine blog).

seasonstringContent season (e.g., “Season 3”).

artiststringArtist credited with the content.

genre

stringGenre that best describes the content (e.g., rock, pop, etc).

album

stringAlbum to which the content belongs; typically for audio.

isrc

stringInternational Standard Recording Code conforming to ISO3901.

producer

objectDetails about the content Producer (Section 3.2.17).

urlstring

URL of the content, for buy-side contextualization or review.

catstring array

Array of IAB content categories that describe the content
producer. Refer to List 5.1.

prodq

integer

Production quality. Refer to List 5.13.

videoquality

integer;
DEPRECATED

Note: Deprecated in favor of prodq.

context

integer

Type of content (game, video, text, etc.). Refer to List 5.18.

contentrating

stringContent rating (e.g., MPAA).

userrating

stringUser rating of the content (e.g., number of stars, likes, etc.).

qagmediarating

integerMedia rating per IQG guidelines. Refer to List 5.19.

keywords

stringComma separated list of keywords describing the content.

livestream

integer

0 = not live, 1 = content is live (e.g., stream, live blog).

sourcerelationshipinteger

0 = indirect, 1 = direct.

len

integer

Length of content in seconds; appropriate for video or audio.

languagestringContent language using ISO-639-1-alpha-2.

embeddable

integer

Indicator of whether or not the content is embeddable (e.g.,
an embeddable video player), where 0 = no, 1 = yes.

dataobject array

Additional content data. Each Data object (Section 3.2.21)
represents a different data source.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

Video quality. Refer to List 5.13.

3.2.17 Object: Producer
This object defines the producer of the content in which the ad will be shown. This is particularly usefulwhen the content is syndicated and may be distributed through different publishers and thus when the
producer and publisher are not necessarily the same entity.
Attribute

Type

DescriptionidstringContent producer or originator ID. Useful if content is
syndicated and may be posted on a site using embed tags.

www.iab.com/openrtb

Page 22

OpenRTB API Specification Version 2.5

IAB Technology Lab

namestringContent producer or originator name (e.g., “Warner Bros”).

catstring array

Array of IAB content categories that describe the content
producer. Refer to List 5.1.

domainstringHighest level domain of the content producer (e.g.,“producer.com”).

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.18 Object: Device
This object provides information pertaining to the device through which the user is interacting. Device
information includes its hardware, platform, location, and carrier data. The device can refer to a mobile
handset, a desktop computer, set top box, or other digital device.
Attribute

Type

Descriptionuastring;recommended

Browser user agent string.

geo

object;recommended

Location of the device assumed to be the user’s current
location defined by a Geo object (Section 3.2.19).

dnt

integer;recommended

Standard “Do Not Track” flag as set in the header by thebrowser, where 0 = tracking is unrestricted, 1 = do not track.

lmt

integer;recommended“Limit Ad Tracking” signal commercially endorsed (e.g., iOS,
Android), where 0 = tracking is unrestricted, 1 = tracking mustbe limited per commercial guidelines.

ip

string;recommended

IPv4 address closest to device.

ipv6

stringIP address closest to device as IPv6.

devicetype

integer

The general type of device. Refer to List 5.21.

makestringDevice make (e.g., “Apple”).

model

stringDevice model (e.g., “iPhone”).

osstringDevice operating system (e.g., “iOS”).

osv

stringDevice operating system version (e.g., “3.1.2”).

hwv

stringHardware version of the device (e.g., “5S” for iPhone 5S).

hinteger

Physical height of the screen in pixels.

w

integer

Physical width of the screen in pixels.

ppi

integer

Screen size as pixels per linear inch.

pxratiofloat

The ratio of physical pixels to device independent pixels.

js

integer

Support for JavaScript, where 0 = no, 1 = yes.

geofetch

integer

Indicates if the geolocation API will be available to JavaScript
code running in the banner, where 0 = no, 1 = yes.

flashverstring

Version of Flash supported by the browser.

languagestringBrowser language using ISO-639-1-alpha-2.

www.iab.com/openrtb

Page 23

OpenRTB API Specification Version 2.5

IAB Technology Lab

carrierstringCarrier or ISP (e.g., “VERIZON”) using exchange curated string
names which should be published to bidders a priori.

mccmncstringMobile carrier as the concatenated MCC-MNC code (e.g.,“310-005” identifies Verizon Wireless CDMA in the USA).
Refer to https://en.wikipedia.org/wiki/Mobile_country_code
for further examples. Note that the dash between the MCC
and MNC parts is required to remove parsing ambiguity.

connectiontype

integer

Network connection type. Refer to List 5.22.

ifa

string

ID sanctioned for advertiser use in the clear (i.e., not hashed).

didsha1

stringHardware device ID (e.g., IMEI); hashed via SHA1.

didmd5stringHardware device ID (e.g., IMEI); hashed via MD5.

dpidsha1stringPlatform device ID (e.g., Android ID); hashed via SHA1.

dpidmd5

stringPlatform device ID (e.g., Android ID); hashed via MD5.

macsha1

string

MAC address of the device; hashed via SHA1.

macmd5string

MAC address of the device; hashed via MD5.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

BEST PRACTICE: There are currently no prominent open source lists for device makes, models, operating
systems, or carriers. Exchanges typically use commercial products or other proprietary lists for these
attributes. Until suitable open standards are available, exchanges are highly encouraged to publish listsof their device make, model, operating system, and carrier values to bidders.
BEST PRACTICE: Proper device IP detection in mobile is not straightforward. Typically it involves startingat the left of the x-forwarded-for header, skipping private carrier networks (e.g., 10.x.x.x or
192.x.x.x), and possibly scanning for known carrier IP ranges. Exchanges are urged to research andimplement this feature carefully when presenting device IP values to bidders.

3.2.19 Object: Geo
This object encapsulates various methods for specifying a geographic location. When subordinate to a
Device object, it indicates the location of the device which can also be interpreted as the user’s current
location. When subordinate to a User object, it indicates the location of the user’s home base (i.e., notnecessarily their current location).
The lat/lon attributes should only be passed if they conform to the accuracy depicted in the typeattribute. For example, the centroid of a geographic region such as postal code should not be passed.
Attribute

Type

Description

lat

float

Latitude from -90.0 to +90.0, where negative is south.

lon

float

Longitude from -180.0 to +180.0, where negative is west.

type

integer

Source of location data; recommended when passing
lat/lon. Refer to List 5.20.

www.iab.com/openrtb

Page 24

OpenRTB API Specification Version 2.5

IAB Technology Lab

accuracy

integer

Estimated location accuracy in meters; recommended whenlat/lon are specified and derived from a device’s location
services (i.e., type = 1). Note that this is the accuracy asreported from the device. Consult OS specific documentation(e.g., Android, iOS) for exact interpretation.

lastfix

integerNumber of seconds since this geolocation fix was established.
Note that devices may cache location data across multiple
fetches. Ideally, this value should be from the time the actual
fix was taken.

ipserviceinteger

Service or provider used to determine geolocation from IP
address if applicable (i.e., type = 2). Refer to List 5.23.

country

stringCountry code using ISO-3166-1-alpha-3.

regionstringRegion code using ISO-3166-2; 2-letter state code if USA.

regionfips104

stringRegion of a country using FIPS 10-4 notation. While OpenRTB
supports this attribute, it has been withdrawn by NIST in 2008.

metro

string

Google metro code; similar to but not exactly Nielsen DMAs.
See Appendix A for a link to the codes.

citystringCity using United Nations Code for Trade & Transport
Locations. See Appendix A for a link to the codes.

zipstring

Zip or postal code.

utcoffset

integer

Local time as the number +/- of minutes from UTC.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.20 Object: User
This object contains information known or derived about the human user of the device (i.e., theaudience for advertising). The user id is an exchange artifact and may be subject to rotation or otherprivacy policies. However, this user ID must be stable long enough to serve reasonably as the basis forfrequency capping and retargeting.
Attribute

Type

Descriptionidstring;recommended

Exchange-specific ID for the user. At least one of id or
buyeruid is recommended.

buyeruid

string;recommended

Buyer-specific ID for the user as mapped by the exchange forthe buyer. At least one of buyeruid or id is recommended.

yob

integerYear of birth as a 4-digit integer.

genderstring

Gender, where “M” = male, “F” = female, “O” = known to beother (i.e., omitted is unknown).

keywords

stringComma separated list of keywords, interests, or intent.

customdata

stringOptional feature to pass bidder data that was set in theexchange’s cookie. The string must be in base85 cookie safecharacters and be in any format. Proper JSON encoding must
be used to include “escaped” quotation marks.

www.iab.com/openrtb

Page 25

OpenRTB API Specification Version 2.5

IAB Technology Lab

geo

objectLocation of the user’s home base defined by a Geo object(Section 3.2.19). This is not necessarily their current location.

data

object array

Additional user data. Each Data object (Section 3.2.21)
represents a different data source.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.21 Object: Data
The data and segment objects together allow additional data about the related object (e.g., user,
content) to be specified. This data may be from multiple sources whether from the exchange itself or
third parties as specified by the id field. A bid request can mix data objects from multiple providers.
The specific data providers in use should be published by the exchange a priori to its bidders.
Attribute

Type

DescriptionidstringExchange-specific ID for the data provider.

namestringExchange-specific name for the data provider.

segment

object array

Array of Segment (Section 3.2.22) objects that contain theactual data values.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

3.2.22 Object: Segment
Segment objects are essentially key-value pairs that convey specific units of data. The parent Dataobject is a collection of such values from a given data provider. The specific segment names and value
options must be published by the exchange a priori to its bidders.
Attribute

Type

DescriptionidstringID of the data segment specific to the data provider.

namestringName of the data segment specific to the data provider.

valuestringString representation of the data segment value.

ext

objectPlaceholder for exchange-specific extensions to OpenRTB.

www.iab.com/openrtb

Page 26

OpenRTB API Specification Version 2.5

IAB Technology Lab

4. Bid Response Specification
RTB responses contain bids that reference specific impressions within a bid request. Bids are in essence
an offer to buy. The bid response consists of the top-level bid response object and optional objects that
depict the specific bids. An empty HTTP response constitutes a no-bid and is in fact the most bandwidth
friendly form of this signal although returning a response with a “no-bid reason” is encouraged. A
malformed response or a response that contains no actual bids will also be interpreted as no-bid.

4.1

Object Model

Following is the object model for the bid response. The top-level object (i.e., in JSON the unnamed
outer object) is denoted as BidResponse in the model. A bid response may contain bids from multiple“seats” (i.e., the buying entity upstream from the actual bidder). In fact a response may containmultiple bids from the same seat; typically but not necessarily from different campaigns. This canimprove the seat’s chances of winning since most exchanges enforce various block lists on behalf of
their publishers.

Figure 4: Bid Response object model.

Referring to the figure, the actual response objects are shown on the left, specifically the BidResponse
top level object the seat specific SeatBid collections of Bid objects. The other objects shown arethose objects from the bid request to which response objects related. Specifically, BidResponse
includes the BidRequest ID for positive tracking purposes, and since a request can include multiple
impressions Bid includes the ID of the Imp for which the bid is an offer to purchase. If a bid is madeunder the terms of a private marketplace deal, the Bid also includes the ID of the specific Deal object.
Not shown in the model figure is an extensions object. This is an object of undefined structure that canbe added to any other object to convey bidder-specific extensions to the standard. Bidders using theseobjects are responsible for publishing their extensions to their exchanges.

www.iab.com/openrtb

Page 27

OpenRTB API Specification Version 2.5

IAB Technology Lab

The following table summarizes the objects in the Bid Response model and serves as an index into thedetailed definitions in the subsections that follow.
ObjectSectionDescription

BidResponse

4.2.1

Top-level object.

SeatBid

4.2.2

Collection of bids made by the bidder on behalf of a specific seat.

Bid

4.2.3

An offer to buy a specific impression under certain business terms.

4.2

Object Specifications

The subsections that follow define each of the objects in the bid response model. Several conventions
are used throughout:Attributes are “required” if their omission would technically break the protocol.
Some optional attributes are denoted “recommended” due to their elevated business importance.
Unless a default value is explicitly specified, an omitted attribute is interpreted as “unknown”.

4.2.1 Object: BidResponse
This object is the top-level bid response object (i.e., the unnamed outer JSON object). The id attributeis a reflection of the bid request ID for logging purposes. Similarly, bidid is an optional response
tracking ID for bidders. If specified, it can be included in the subsequent win notice call if the bidder
wins. At least one seatbid object is required, which contains at least one bid for an impression. Other
attributes are optional.
To express a “no-bid”, the options are to return an empty response with HTTP 204. Alternately if thebidder wishes to convey to the exchange a reason for not bidding, just a BidResponse object isreturned with a reason code in the nbr attribute.
Attribute

Type

Descriptionidstring; required

ID of the bid request to which this is a response.

seatbid

object array

Array of seatbid objects; 1+ required if a bid is to be made.

bidid

stringBidder generated response ID to assist with logging/tracking.

cur

string;Bid currency using ISO-4217 alpha codes.

default “USD”
customdata

stringOptional feature to allow a bidder to set data in theexchange’s cookie. The string must be in base85 cookie safecharacters and be in any format. Proper JSON encoding must
be used to include “escaped” quotation marks.

nbr

integer

Reason for not bidding. Refer to List 5.24.

ext

objectPlaceholder for bidder-specific extensions to OpenRTB.

www.iab.com/openrtb

Page 28

OpenRTB API Specification Version 2.5

IAB Technology Lab

4.2.2 Object: SeatBid
A bid response can contain multiple SeatBid objects, each on behalf of a different bidder seat and eachcontaining one or more individual bids. If multiple impressions are presented in the request, the groupattribute can be used to specify if a seat is willing to accept any impressions that it can win (default) or if
it is only interested in winning any if it can win them all as a group.
Attribute

Type

Descriptionbidobject array;required

Array of 1+ Bid objects (Section 4.2.3) each related to an
impression. Multiple bids can relate to the same impression.

seat

stringID of the buyer seat (e.g., advertiser, agency) on whose behalf
this bid is made.

group

integer;default 00 = impressions can be won individually; 1 = impressions must
be won or lost as a group.

ext

objectPlaceholder for bidder-specific extensions to OpenRTB.

4.2.3 Object: Bid
A SeatBid object contains one or more Bid objects, each of which relates to a specific impression in thebid request via the impid attribute and constitutes an offer to buy that impression for a given price.
Attribute

Type

Descriptionidstring; required

Bidder generated bid ID to assist with logging/tracking.

impid

string; required

ID of the Imp object in the related bid request.

price

float; required

Bid price expressed as CPM although the actual transaction isfor a unit impression only. Note that while the type indicatesfloat, integer math is highly recommended when handlingcurrencies (e.g., BigDecimal in Java).

nurl

string

Win notice URL called by the exchange if the bid wins (notnecessarily indicative of a delivered, viewed, or billable ad);optional means of serving ad markup. Substitution macros(Section 4.4) may be included in both the URL and optionally
returned markup.

burlstringBilling notice URL called by the exchange when a winning bid
becomes billable based on exchange-specific business policy(e.g., typically delivered, viewed, etc.). Substitution macros(Section 4.4) may be included.

lurlstringLoss notice URL called by the exchange when a bid is known tohave been lost. Substitution macros (Section 4.4) may be
included. Exchange-specific policy may preclude support for
loss notices or the disclosure of winning clearing prices
resulting in ${AUCTION_PRICE} macros being removed (i.e.,
replaced with a zero-length string).

adm

stringOptional means of conveying ad markup in case the bid wins;supersedes the win notice if markup is included in both.
Substitution macros (Section 4.4) may be included.

www.iab.com/openrtb

Page 29

OpenRTB API Specification Version 2.5

IAB Technology Lab

adid

stringID of a preloaded ad to be served if the bid wins.

adomainstring array

Advertiser domain for block list checking (e.g., “ford.com”).
This can be an array of for the case of rotating creatives.
Exchanges can mandate that only one domain is allowed.

bundlestringA platform-specific application identifier intended to be
unique to the app and independent of the exchange. On
Android, this should be a bundle or package name (e.g.,com.foo.mygame). On iOS, it is a numeric ID.

iurlstring

URL without cache-busting to an image that is representativeof the content of the campaign for ad quality/safety checking.

cidstringCampaign ID to assist with ad quality checking; the collectionof creatives for which iurl should be representative.

crid

stringCreative ID to assist with ad quality checking.

tacticstringTactic ID to enable buyers to label bids for reporting to theexchange the tactic through which their bid was submitted.
The specific usage and meaning of the tactic ID should becommunicated between buyer and exchanges a priori.

catstring array

IAB content categories of the creative. Refer to List 5.1.

attr

integer arraySet of attributes describing the creative. Refer to List 5.3.

api

integer

API required by the markup if applicable. Refer to List 5.6.

protocolintegerVideo response protocol of the markup if applicable. Refer to
List 5.8.

qagmediarating

integer

Creative media rating per IQG guidelines. Refer to List 5.19.

languagestringLanguage of the creative using ISO-639-1-alpha-2. The nonstandard code “xx” may also be used if the creative has no
linguistic content (e.g., a banner with just a company logo).

dealidstringReference to the deal.id from the bid request if this bid
pertains to a private marketplace direct deal.

w

integer

Width of the creative in device independent pixels (DIPS).

hinteger

Height of the creative in device independent pixels (DIPS).

wratiointeger

Relative width of the creative when expressing size as a ratio.
Required for Flex Ads.

hratiointeger

Relative height of the creative when expressing size as a ratio.
Required for Flex Ads.

exp

integer

Advisory as to the number of seconds the bidder is willing to
wait between the auction and the actual impression.

ext

objectPlaceholder for bidder-specific extensions to OpenRTB.

For each bid, the nurl attribute contains the win notice URL. If the bidder wins the impression, theexchange calls this notice URL to inform the bidder of the win and to convey certain information using
substitution macros (see Section 4.4) such as the clearing price. The win notice return or the adm
attribute can be used to serve markup (see Section 4.3). In either case, the exchange will also apply the
aforementioned substitution to any macros found in the markup.

www.iab.com/openrtb

Page 30

OpenRTB API Specification Version 2.5

IAB Technology Lab

BEST PRACTICE: The essential function of the win notice is to inform a bidder that they won an auction. It
does not necessarily imply ad delivery, creative viewability, or billability. Exchanges are highly
encouraged to publish to their bidders their event triggers, billing policies, and any other meaning they
attach to the win notice. Also, please refer to Section 7.2 for additional guidance on expirations.
BEST PRACTICE: Firing of the billing notice should be server-side and as “close” as possible to where theexchange books revenue in order to minimize discrepancies between exchange and bidder.
BEST PRACTICE: For VAST Video, the IAB prescribes that the VAST impression event is the official signalthat the impression is billable. If the burl attribute is specified, it too should be fired at the same time if
the exchange is adhering to this policy. However, subtle technical issues may lead to additional
discrepancies and bidders are cautioned to avoid this scenario.
Several other attributes are used for ad quality checks or enforcing publisher restrictions. These include
the advertiser domain via adomain, a non-cache-busted URL to an image representative of the content
of the campaign via iurl, an ID of the campaign and of the creative within the campaign via cid andcrid respectively, an array of creative attribute via attr, and the dimensions via h and w. If the bid
pertains to a private marketplace deal, the dealid attribute is used to reference that agreement fromthe bid request.

4.3

Ad Serving Options

The fulfilment of an RTB transaction within the scope of this OpenRTB specification lies in the delivery ofmarkup. Depending on the impression and other ad type constraints, this markup can be XHTML,
HTML5, XHTML or HTML5 with embedded JavaScript, a VAST document for video, a Native ad unit
structure, and potentially other formats in the future.
The OpenRTB specification does not require any processing of the ad markup by the exchange otherthan macro substitution (refer to Section 4.4) and delivery to the supply-side. There are, however,multiple standard methods for transferring markup from the bidder to the exchange. The method used
is at the discretion of the bidder, but an OpenRTB compliant exchange is expected to support all
methods as defined in the subsections that follow.

4.3.1 Markup Served on the Win Notice
In this method, ad markup is returned to the exchange is via the win notice. In this case, the responsebody of the win notice call (i.e., invoking the bid.nurl attribute) contains the ad markup and only thead markup; there must be no other structured data in the response body. Using this method, thebid.adm attribute must be omitted.

4.3.2 Markup Served in the Bid
In this method, ad markup is returned directly in the bid itself. This is accomplished via the bid.adm
attribute. If both the adm attribute and win notice return data, the adm contents will take precedence.

4.3.3 Comparison of Ad Serving Approaches
Each of the ad serving methods has its own advantages that may be of varying importance to either theexchange or the bidder.

www.iab.com/openrtb

Page 31OpenRTB API Specification Version 2.5

IAB Technology Lab

Ad Served on the Win NoticeReduced Bandwidth Costs: Serving ad markup only upon winning can save large amounts of
bandwidth usage, the costs for which can be large at high volumes or when sending multiple bids
per bid response.
Additional Bidder Flexibility: Bidders may typically know the ad they will serve at the time of bid, but
this provides an additional optional decision point after the clearing price has been established.

Ad Served in the BidReduced Risk of Forfeiture: A forfeit is the scenario in which a bidder wins, but forfeits due to failure
to serve the ad markup. The risk of an additional HTTP failure (e.g., calling the win notice) is
mitigated by this method.
Potential Concurrency: The exchange can choose to return that ad markup and call the win noticeconcurrently, thereby improving user experience.



4.4

Substitution Macros

The win notice and billing notice URLs and their format are defined by the bidder. In order for theexchange to convey certain information to the bidder (e.g., the clearing price), a number of substitution
macros can be inserted into these URLs. Prior to calling a win or billing notice URL, the exchange will
search the specified URL for any of the defined macros and replace them with the appropriate data.
Note that the substitution is simple in the sense that wherever a legal macro is found, it will be replaced
without regard for syntax correctness. Furthermore, if the source value is an optional parameter thatwas not specified, the macro will simply be removed (i.e., replaced with a zero-length string).
These same substitution macros can also be placed in the ad markup. The exchange will perform thesame data substitutions as in the aforementioned notice URLs. This occurs irrespective of whether themarkup is returned on the win notice or passed in the bid.adm attribute of the bid response. A use
case for macros in the ad markup might be when a bidder prefers to receive its win notification from thedevice itself. To accomplish this, the bidder would include a tracking pixel in the ad markup, the URL for
which would include any of the available macros.

Macro

Description${AUCTION_ID}

ID of the bid request; from BidRequest.id attribute.

${AUCTION_BID_ID}

ID of the bid; from BidResponse.bidid attribute.

${AUCTION_IMP_ID}

ID of the impression just won; from imp.id attribute.

${AUCTION_SEAT_ID}

ID of the bidder seat for whom the bid was made.

${AUCTION_AD_ID}

ID of the ad markup the bidder wishes to serve; from bid.adid attribute.

${AUCTION_PRICE}

Clearing price using the same currency and units as the bid.

${AUCTION_CURRENCY}

The currency used in the bid (explicit or implied); for confirmation only.

${AUCTION_MBR}

Market Bid Ratio defined as: clearance price / bid price.

${AUCTION_LOSS}

Loss reason codes. Refer to List 5.25.

www.iab.com/openrtb

Page 32

OpenRTB API Specification Version 2.5

IAB Technology Lab

Note that OpenRTB compliance exchanges must support all macros for which data is available andsupport substitution in both markup and URLs for win and billing notification.
BEST PRACTICE: When rendering markup for test or ad quality purposes, some macro values (e.g., clearing
price) may not be known. In these cases, substitute “AUDIT” as the macro value.
Prior to substitution, macro data values can be encoded for security purposes using various obfuscationor encryption algorithms. This may be of particular interest for use cases such as the foregoing where
price information is carried beyond the exchange, through the publisher, and into the device browser via
a tracking pixel in the markup.
To specify that a particular macro is to be encoded, the suffix “:X” should be appended to the macro
name, where X is a string that indicates the algorithm to be used. Algorithms choices are not defined bythis specification and must be mutually agreed upon between exchange and bidder. As an example,
suppose that the price macro is to be encoded using Base64 and that its code is “B64”. The macro
would then be written as follows:${AUCTION_PRICE:B64}

BEST PRACTICE: Encoding of macro data should be used sparingly due to the additional processing
overhead. For communications strictly between exchange and bidder (e.g., a win notice called from theexchange), encoding is generally considered unnecessary.

www.iab.com/openrtb

Page 33

OpenRTB API Specification Version 2.5

IAB Technology Lab

5. Enumerated Lists Specification
All reference lists are actively maintained by the IAB on the OpenRTB website. As such, implementersshould ensure they are working from the latest lists and enumerations.

5.1

Content Categories

The following list represents the IAB’s contextual taxonomy for categorization. Standard IDs have been
adopted to easily support the communication of primary and secondary categories for various objects.
This OpenRTB table has values derived from the IAB Tech Lab Content Taxonomy. Practitioners should
keep in sync with updates as published on www.iab.com.
Value

Description

IAB1

Arts & Entertainment

IAB1-1

Books & Literature

IAB1-2

Celebrity Fan/Gossip

IAB1-3

Fine Art

IAB1-4

Humor

IAB1-5

Movies

IAB1-6

Music

IAB1-7

Television

IAB2

Automotive

IAB2-1

Auto Parts

IAB2-2

Auto Repair

IAB2-3

Buying/Selling Cars

IAB2-4

Car Culture

IAB2-5

Certified Pre-Owned

IAB2-6

Convertible

IAB2-7

Coupe

IAB2-8Crossover

IAB2-9Diesel

IAB2-10

Electric Vehicle

IAB2-11

HatchbackIAB2-12HybridIAB2-13

LuxuryIAB2-14

Minivan

IAB2-15

Motorcycles

IAB2-16

Off-Road Vehicles

IAB2-17

Performance Vehicles

www.iab.com/openrtb

Page 34

OpenRTB API Specification Version 2.5

IAB2-18

Pickup

IAB2-19

Road-Side AssistanceIAB2-20

Sedan

IAB2-21

Trucks & Accessories

IAB2-22

Vintage Cars

IAB2-23

Wagon

IAB3

Business

IAB3-1Advertising

IAB3-2Agriculture

IAB3-3

Biotech/Biomedical

IAB3-4

Business Software

IAB3-5Construction

IAB3-6

Forestry

IAB3-7

Government

IAB3-8

Green Solutions

IAB3-9Human Resources

IAB3-10

Logistics

IAB3-11

Marketing

IAB3-12

MetalsIAB4

Careers

IAB4-1

Career Planning

IAB4-2

College

IAB4-3Financial Aid

IAB4-4

Job Fairs

IAB4-5

Job Search

IAB4-6

Resume Writing/Advice

IAB4-7

Nursing

IAB4-8Scholarships

IAB4-9Telecommuting

IAB4-10

U.S. Military

IAB4-11

Career Advice

IAB5

Education

IAB5-1

7-12 Education

IAB5-2

Adult Education

IAB5-3

Art History

IAB5-4

College Administration

IAB5-5

College Life

www.iab.com/openrtb

IAB Technology Lab

Page 35

OpenRTB API Specification Version 2.5

IAB5-6

Distance Learning

IAB5-7

English as a 2nd Language

IAB5-8

Language Learning

IAB5-9Graduate School

IAB5-10

Homeschooling

IAB5-11Homework/Study Tips

IAB5-12K-6 Educators

IAB5-13

Private School

IAB5-14

Special Education

IAB5-15

Studying Business

IAB6

Family & Parenting

IAB6-1Adoption

IAB6-2Babies & Toddlers

IAB6-3

Daycare/Pre School

IAB6-4

Family Internet

IAB6-5

Parenting - K-6 Kids

IAB6-6

Parenting teens

IAB6-7Pregnancy

IAB6-8Special Needs Kids

IAB6-9Eldercare

IAB7

Health & Fitness

IAB7-1

Exercise

IAB7-2ADD

IAB7-3

AIDS/HIV

IAB7-4Allergies

IAB7-5

Alternative Medicine

IAB7-6Arthritis

IAB7-7

AsthmaIAB7-8Autism/PDD

IAB7-9Bipolar Disorder

IAB7-10

Brain Tumor

IAB7-11

Cancer

IAB7-12Cholesterol

IAB7-13Chronic Fatigue Syndrome

IAB7-14Chronic Pain

IAB7-15

Cold & Flu

IAB7-16

Deafnesswww.iab.com/openrtb

IAB Technology Lab

Page 36

OpenRTB API Specification Version 2.5

IAB7-17

Dental Care

IAB7-18

Depression

IAB7-19

Dermatology

IAB7-20

Diabetes

IAB7-21

Epilepsy

IAB7-22

GERD/Acid Reflux

IAB7-23

Headaches/Migraines

IAB7-24

Heart Disease

IAB7-25

Herbs for Health

IAB7-26

Holistic Healing

IAB7-27

IBS/Crohn’s Disease

IAB7-28

Incest/Abuse Support

IAB7-29

Incontinence

IAB7-30

Infertility

IAB7-31

Men’s Health

IAB7-32

Nutrition

IAB7-33

Orthopedics

IAB7-34

Panic/Anxiety Disorders

IAB7-35

Pediatrics

IAB7-36

Physical Therapy

IAB7-37

Psychology/Psychiatry

IAB7-38

Senior Health

IAB7-39

Sexuality

IAB7-40

Sleep Disorders

IAB7-41

Smoking Cessation

IAB7-42

Substance Abuse

IAB7-43

Thyroid Disease

IAB7-44

Weight Loss

IAB7-45

Women's Health

IAB8

Food & Drink

IAB8-1

American Cuisine

IAB8-2

Barbecues & Grilling

IAB8-3

Cajun/Creole

IAB8-4Chinese Cuisine

IAB8-5

Cocktails/Beer

IAB8-6

Coffee/Tea

IAB8-7

Cuisine-Specificwww.iab.com/openrtb

IAB Technology Lab

Page 37

OpenRTB API Specification Version 2.5

IAB8-8

Desserts & Baking

IAB8-9Dining Out

IAB8-10

Food Allergies

IAB8-11

French Cuisine

IAB8-12

Health/Low-Fat Cooking

IAB8-13

Italian Cuisine

IAB8-14

Japanese Cuisine

IAB8-15

Mexican Cuisine

IAB8-16Vegan

IAB8-17

Vegetarian

IAB8-18

Wine

IAB9

Hobbies & Interests

IAB9-1

Art/Technology

IAB9-2

Arts & Crafts

IAB9-3

Beadwork

IAB9-4

Bird-Watching

IAB9-5

Board Games/Puzzles

IAB9-6

Candle & Soap Making

IAB9-7

Card Games

IAB9-8Chess

IAB9-9Cigars

IAB9-10

Collecting

IAB9-11

Comic Books

IAB9-12Drawing/Sketching

IAB9-13

Freelance Writing

IAB9-14

Genealogy

IAB9-15

Getting Published

IAB9-16

Guitar

IAB9-17

Home Recording

IAB9-18

Investors & Patents

IAB9-19

Jewelry Making

IAB9-20

Magic & Illusion

IAB9-21

Needlework

IAB9-22

Painting

IAB9-23

Photography

IAB9-24

Radio

IAB9-25

Roleplaying Gameswww.iab.com/openrtb

IAB Technology Lab

Page 38

OpenRTB API Specification Version 2.5

IAB9-26

Sci-Fi & Fantasy

IAB9-27

Scrapbooking

IAB9-28

Screenwriting

IAB9-29

Stamps & Coins

IAB9-30

Video & Computer Games

IAB9-31

Woodworking

IAB10

Home & Garden

IAB10-1

Appliances

IAB10-2

Entertaining

IAB10-3

Environmental Safety

IAB10-4

Gardening

IAB10-5

Home Repair

IAB10-6

Home Theater

IAB10-7

Interior Decorating

IAB10-8

Landscaping

IAB10-9Remodeling & Construction

IAB11

Law, Government, & Politics

IAB11-1

Immigration

IAB11-2

Legal Issues

IAB11-3

U.S. Government Resources

IAB11-4

Politics

IAB11-5

Commentary

IAB12

News

IAB12-1

International News

IAB12-2

National News

IAB12-3

Local News

IAB13

Personal Finance

IAB13-1

Beginning Investing

IAB13-2

Credit/Debt & Loans

IAB13-3

Financial News

IAB13-4

Financial Planning

IAB13-5

Hedge Fund

IAB13-6

Insurance

IAB13-7

Investing

IAB13-8

Mutual Funds

IAB13-9

Options

IAB13-10

Retirement Planning

www.iab.com/openrtb

IAB Technology Lab

Page 39

OpenRTB API Specification Version 2.5

IAB13-11

Stocks

IAB13-12

Tax Planning

IAB14

Society

IAB14-1

Dating

IAB14-2

Divorce Support

IAB14-3

Gay Life

IAB14-4

Marriage

IAB14-5

Senior Living

IAB14-6

Teens

IAB14-7

Weddings

IAB14-8Ethnic Specific

IAB15

Science

IAB15-1

Astrology

IAB15-2

Biology

IAB15-3

Chemistry

IAB15-4

Geology

IAB15-5

Paranormal Phenomena

IAB15-6

Physics

IAB15-7

Space/Astronomy

IAB15-8

Geography

IAB15-9

BotanyIAB15-10

Weather

IAB16

Pets

IAB16-1

Aquariums

IAB16-2

Birds

IAB16-3

Cats

IAB16-4

Dogs

IAB16-5Large Animals

IAB16-6

ReptilesIAB16-7

Veterinary Medicine

IAB17

Sports

IAB17-1

Auto Racing

IAB17-2

Baseball

IAB17-3

Bicycling

IAB17-4

Bodybuilding

IAB17-5

Boxing

IAB17-6

Canoeing/Kayaking

www.iab.com/openrtb

IAB Technology Lab

Page 40

OpenRTB API Specification Version 2.5

IAB17-7

Cheerleading

IAB17-8

Climbing

IAB17-9

Cricket

IAB17-10

Figure Skating

IAB17-11

Fly Fishing

IAB17-12

Football

IAB17-13

Freshwater Fishing

IAB17-14

Game & Fish

IAB17-15

Golf

IAB17-16

Horse Racing

IAB17-17

Horses

IAB17-18

Hunting/Shooting

IAB17-19

Inline Skating

IAB17-20

Martial Arts

IAB17-21

Mountain Biking

IAB17-22

NASCAR Racing

IAB17-23

Olympics

IAB17-24

Paintball

IAB17-25

Power & Motorcycles

IAB17-26

Pro Basketball

IAB17-27

Pro Ice Hockey

IAB17-28

Rodeo

IAB17-29

Rugby

IAB17-30

Running/Jogging

IAB17-31

Sailing

IAB17-32

Saltwater Fishing

IAB17-33

Scuba Diving

IAB17-34

Skateboarding

IAB17-35

Skiing

IAB17-36

Snowboarding

IAB17-37

Surfing/Body-Boarding

IAB17-38

Swimming

IAB17-39

Table Tennis/Ping-Pong

IAB17-40

Tennis

IAB17-41

Volleyball

IAB17-42

Walking

IAB17-43

Waterski/Wakeboard

www.iab.com/openrtb

IAB Technology Lab

Page 41

OpenRTB API Specification Version 2.5

IAB17-44

World Soccer

IAB18

Style & Fashion

IAB18-1

BeautyIAB18-2

Body Art

IAB18-3

Fashion

IAB18-4

Jewelry

IAB18-5

Clothing

IAB18-6

Accessories

IAB19

Technology & Computing

IAB19-1

3-D Graphics

IAB19-2

Animation

IAB19-3

Antivirus Software

IAB19-4

C/C++

IAB19-5

Cameras & Camcorders

IAB19-6

Cell Phones

IAB19-7

Computer Certification

IAB19-8

Computer Networking

IAB19-9Computer Peripherals

IAB19-10

Computer Reviews

IAB19-11

Data Centers

IAB19-12

Databases

IAB19-13

Desktop Publishing

IAB19-14

Desktop Video

IAB19-15

Email

IAB19-16

Graphics Software

IAB19-17

Home Video/DVD

IAB19-18

Internet Technology

IAB19-19

Java

IAB19-20

JavaScript

IAB19-21

Mac Support

IAB19-22

MP3/MIDI

IAB19-23

Net Conferencing

IAB19-24

Net for Beginners

IAB19-25

Network Security

IAB19-26

Palmtops/PDAs

IAB19-27

PC Support

IAB19-28

Portablewww.iab.com/openrtb

IAB Technology Lab

Page 42OpenRTB API Specification Version 2.5

IAB19-29

Entertainment

IAB19-30

Shareware/Freeware

IAB19-31

Unix

IAB19-32

Visual Basic

IAB19-33

Web Clip Art

IAB19-34

Web Design/HTML

IAB19-35

Web Search

IAB19-36

Windows

IAB20

Travel

IAB20-1

Adventure Travel

IAB20-2

Africa

IAB20-3

Air Travel

IAB20-4

Australia & New Zealand

IAB20-5

Bed & Breakfasts

IAB20-6

Budget Travel

IAB20-7

Business Travel

IAB20-8

By US Locale

IAB20-9Camping

IAB20-10

Canada

IAB20-11

Caribbean

IAB20-12

Cruises

IAB20-13

Eastern Europe

IAB20-14

Europe

IAB20-15

France

IAB20-16

Greece

IAB20-17

Honeymoons/Getaways

IAB20-18

Hotels

IAB20-19

Italy

IAB20-20

Japan

IAB20-21

Mexico & Central America

IAB20-22

National Parks

IAB20-23

South America

IAB20-24

Spas

IAB20-25

Theme Parks

IAB20-26

Traveling with Kids

IAB20-27

United Kingdom

IAB21

Real Estate

www.iab.com/openrtb

IAB Technology Lab

Page 43

OpenRTB API Specification Version 2.5

IAB21-1

Apartments

IAB21-2

Architects

IAB21-3

Buying/Selling Homes

IAB22

Shopping

IAB22-1

Contests & Freebies

IAB22-2

Couponing

IAB22-3Comparison

IAB22-4

Engines

IAB23

Religion & Spirituality

IAB23-1

Alternative Religions

IAB23-2

Atheism/Agnosticism

IAB23-3

Buddhism

IAB23-4

Catholicism

IAB23-5

Christianity

IAB23-6

Hinduism

IAB23-7

Islam

IAB23-8

Judaism

IAB23-9Latter-Day Saints

IAB23-10

Pagan/Wiccan

IAB24

Uncategorized

IAB25

Non-Standard Content

IAB25-1

Unmoderated UGC

IAB25-2

Extreme Graphic/Explicit Violence

IAB25-3

Pornography

IAB25-4

Profane Content

IAB25-5

Hate Content

IAB25-6

Under Construction

IAB25-7

Incentivized

IAB26

Illegal Content

IAB26-1

Illegal Content

IAB26-2

Warez

IAB26-3

Spyware/Malware

IAB26-4

Copyright Infringement

www.iab.com/openrtb

IAB Technology Lab

Page 44OpenRTB API Specification Version 2.5

5.2

IAB Technology Lab

Banner Ad Types

The following table indicates the types of ads that can be accepted by the exchange unless restricted bypublisher site settings.
Value

Description

1

XHTML Text Ad (usually mobile)

2

XHTML Banner Ad. (usually mobile)

3

JavaScript Ad; must be valid XHTML (i.e., Script Tags Included)

4

iframe5.3

Creative Attributes

The following table specifies a standard list of creative attributes that can describe an ad being served orserve as restrictions of thereof.
Value

Description

1

Audio Ad (Auto-Play)

2

Audio Ad (User Initiated)

3

Expandable (Automatic)

4

Expandable (User Initiated - Click)5

Expandable (User Initiated - Rollover)6

In-Banner Video Ad (Auto-Play)

7

In-Banner Video Ad (User Initiated)

8

Pop (e.g., Over, Under, or Upon Exit)

9

Provocative or Suggestive Imagery

10

Shaky, Flashing, Flickering, Extreme Animation, Smileys

11

Surveys

12

Text Only

13

User Interactive (e.g., Embedded Games)

14

Windows Dialog or Alert Style

15

Has Audio On/Off Button

16

Ad Provides Skip Button (e.g. VPAID-rendered skip button on pre-roll video)

17

Adobe Flash5.4

Ad Position

The following table specifies the position of the ad as a relative measure of visibility or prominence. This
OpenRTB table has values derived from the Inventory Quality Guidelines (IQG). Practitioners shouldwww.iab.com/openrtb

Page 45

OpenRTB API Specification Version 2.5

IAB Technology Lab

keep in sync with updates to the IQG values as published on IAB.com. Values “4” - “7” apply to apps per
the mobile addendum to IQG version 2.1.
Value

Description0

Unknown

1

Above the Fold

2

DEPRECATED - May or may not be initially visible depending on screen size/resolution.

3

Below the Fold

4

Header5Footer6

Sidebar

7

Full Screen

5.5

Expandable Direction

The following table lists the directions in which an expandable ad may expand, given the positioning of
the ad unit on the page and constraints imposed by the content.
Value

Description

1

Left

2

Right

3

Up

4

Down

5

Full Screen

5.6

API Frameworks

The following table is a list of API frameworks supported by the publisher.
Value

Description

1

VPAID 1.0

2

VPAID 2.0

3

MRAID-1

4

ORMMA

5

MRAID-2

6

MRAID-3

www.iab.com/openrtb

Page 46

OpenRTB API Specification Version 2.5

5.7

IAB Technology Lab

Video Linearity

The following table indicates the options for video linearity. “In-stream” or “linear” video refers to preroll, post-roll, or mid-roll video ads where the user is forced to watch ad in order to see the video
content. “Overlay” or “non-linear” refer to ads that are shown on top of the video content.
This OpenRTB table has values derived from the Inventory Quality Guidelines (IQG). Practitioners should
keep in sync with updates to the IQG values.
Value

Description

1

Linear / In-Stream

2

Non-Linear / Overlay

5.8

Protocols

The following table lists the options for the various bid response protocols that could be supported by
an exchange.
Value

Description

1

VAST 1.0

2

VAST 2.0

3

VAST 3.0

4

VAST 1.0 Wrapper

5

VAST 2.0 Wrapper

6

VAST 3.0 Wrapper

7

VAST 4.0

8

VAST 4.0 Wrapper

9

DAAST 1.0

10

DAAST 1.0 Wrapper

5.9

Video Placement Types

The following table lists the various types of video placements derived largely from the IAB Digital Video
Guidelines.
Value

Description

1

In-Stream
Played before, during or after the streaming video content that the consumer has requested(e.g., Pre-roll, Mid-roll, Post-roll).

www.iab.com/openrtb

Page 47

OpenRTB API Specification Version 2.5

2

IAB Technology Lab

In-Banner
Exists within a web banner that leverages the banner space to deliver a video experience as
opposed to another static or rich media format. The format relies on the existence of display
ad inventory on the page for its delivery.

3

In-Article
Loads and plays dynamically between paragraphs of editorial content; existing as a standalone
branded message.

4

In-Feed - Found in content, social, or product feeds.

5Interstitial/Slider/Floating
Covers the entire or a portion of screen area, but is always on screen while displayed (i.e.
cannot be scrolled out of view). Note that a full-screen interstitial (e.g., in mobile) can be
distinguished from a floating/slider unit by the imp.instl field.

5.10 Playback Methods
The following table lists the various playback methods.
Value

Description

1

Initiates on Page Load with Sound On

2

Initiates on Page Load with Sound Off by Default

3

Initiates on Click with Sound On

4

Initiates on Mouse-Over with Sound On

5

Initiates on Entering Viewport with Sound On

6

Initiates on Entering Viewport with Sound Off by Default

5.11 Playback Cessation Modes
The following table lists the various modes for when playback terminates.
Value

Description

1

On Video Completion or when Terminated by User

2

On Leaving Viewport or when Terminated by User

3

On Leaving Viewport Continues as a Floating/Slider Unit until Video Completion or when
Terminated by User

5.12 Start Delay
The following table lists the various options for the video or audio start delay. If the start delay value isgreater than 0, then the position is mid-roll and the value indicates the start delay.

www.iab.com/openrtb

Page 48

OpenRTB API Specification Version 2.5

Value

Description> 0

Mid-Roll (value indicates start delay in second)

0

Pre-Roll-1

Generic Mid-Roll-2

Generic Post-Roll

IAB Technology Lab

5.13 Production Quality
The following table lists the options for content quality. These values are defined by the IAB; refer towww.iab.com/wp-content/uploads/2015/03/long-form-video-final.pdf for more information.
Value

Description0

Unknown

1

Professionally Produced

2

Prosumer

3

User Generated (UGC)

5.14 Companion Types
The following table lists the options to indicate markup types allowed for companion ads that apply tovideo and audio ads. This table is derived from VAST 2.0+ and DAAST 1.0 specifications. Refer towww.iab.com/guidelines/digital-video-suite for more information.
Value

Description

1

Static Resource

2

HTML Resource

3

iframe Resource

5.15 Content Delivery Methods
The following table lists the various options for the delivery of video or audio content.
Value

Description

1

Streaming

2

Progressive

3

Download

www.iab.com/openrtb

Page 49

OpenRTB API Specification Version 2.5

IAB Technology Lab

5.16 Feed Types
The following table lists the types of feeds, typically for audio.
Value

Description

1

Music Service

2

FM/AM Broadcast

3

Podcast5.17 Volume Normalization Modes
The following table lists the types of volume normalization modes, typically for audio.
Value

Description

0

None

1

Ad Volume Average Normalized to Content

2

Ad Volume Peak Normalized to Content

3

Ad Loudness Normalized to Content

4

Custom Volume Normalization

5.18 Content Context
The following table lists the various options for indicating the type of content being used or consumed
by the user in which the impression will appear. This OpenRTB table has values derived from theInventory Quality Guidelines (IQG). Practitioners should keep in sync with updates to the IQG values.
Value

Description

1

Video (i.e., video file or stream such as Internet TV broadcasts)

2

Game (i.e., an interactive software game)3

Music (i.e., audio file or stream such as Internet radio broadcasts)

4

Application (i.e., an interactive software application)

5

Text (i.e., primarily textual document such as a web page, eBook, or news article)

6

Other (i.e., none of the other categories applies)

7

Unknown

5.19 IQG Media Ratings
The following table lists the media ratings used in describing content based on the IQG 2.1
categorization. Refer to www.iab.com/guidelines/digital-video-suite for more information.

www.iab.com/openrtb

Page 50

OpenRTB API Specification Version 2.5

Value

Description

1

All Audiences2

Everyone Over 123

Mature Audiences

IAB Technology Lab

5.20 Location TypeThe following table lists the options to indicate how the geographic information was determined.
Value

Description

1

GPS/Location Services

2

IP Address

3

User provided (e.g., registration data)

5.21 Device TypeThe following table lists the type of device from which the impression originated.
OpenRTB version 2.2 of the specification added distinct values for Mobile and Tablet. It is
recommended that any bidder adding support for 2.2 treat a value of 1 as an acceptable alias of 4 & 5.
This OpenRTB table has values derived from the Inventory Quality Guidelines (IQG). Practitioners should
keep in sync with updates to the IQG values.
Value

Description

Notes

1

Mobile/Tablet

Version 2.0

2

Personal Computer

Version 2.0

3Connected TV

Version 2.0

4

Phone

New for Version 2.2

5

TabletNew for Version 2.2

6

Connected Device

New for Version 2.2

7

Set Top Box

New for Version 2.2

5.22 Connection TypeThe following table lists the various options for the type of device connectivity.
Value

Description0

Unknown

1

Ethernet

www.iab.com/openrtb

Page 51

OpenRTB API Specification Version 2.5

2

WIFI

3

Cellular Network – Unknown Generation

4

Cellular Network – 2G

5

Cellular Network – 3G

6

Cellular Network – 4G

IAB Technology Lab

5.23 IP Location Services
The following table lists the services and/or vendors used for resolving IP addresses to geolocations.
Value

Description1

ip2location

2

Neustar (Quova)

3

MaxMind

4

NetAcuity (Digital Element)

5.24 No-Bid Reason Codes
The following table lists the options for a bidder to signal the exchange as to why it did not offer a bid
for the impression.
Value

Description0

Unknown Error

1

Technical Error

2

Invalid Request

3

Known Web Spider

4

Suspected Non-Human Traffic

5

Cloud, Data center, or Proxy IP

6Unsupported Device

7

Blocked Publisher or Site

8

Unmatched User

9

Daily Reader Cap Met

10

Daily Domain Cap Met

5.25 Loss Reason Codes
The following table lists the options for an exchange to inform a bidder as to the reason why they did
not win an impression.

www.iab.com/openrtb

Page 52

OpenRTB API Specification Version 2.5

IAB Technology Lab

Value

Description

0

Bid Won1

Internal Error

2

Impression Opportunity Expired

3

Invalid Bid Response

4

Invalid Deal ID

5

Invalid Auction ID

6

Invalid (i.e., malformed) Advertiser Domain

7

Missing Markup

8

Missing Creative ID

9Missing Bid Price

10

Missing Minimum Creative Approval Data

100

Bid was Below Auction Floor101

Bid was Below Deal Floor

102

Lost to Higher Bid

103

Lost to a Bid for a PMP Deal

104

Buyer Seat Blocked

200

Creative Filtered - General; reason unknown.

201

Creative Filtered - Pending processing by Exchange (e.g., approval, transcoding, etc.)

202

Creative Filtered - Disapproved by Exchange

203

Creative Filtered - Size Not Allowed

204

Creative Filtered - Incorrect Creative Format

205

Creative Filtered - Advertiser Exclusions

206

Creative Filtered – App Bundle Exclusions

207

Creative Filtered - Not Secure

208

Creative Filtered - Language Exclusions

209

Creative Filtered - Category Exclusions

210

Creative Filtered - Creative Attribute Exclusions

211

Creative Filtered - Ad Type Exclusions

212

Creative Filtered - Animation Too Long

213

Creative Filtered - Not Allowed in PMP Deal

≥ 1000Exchange specific (should be communicated to bidders a priori)

www.iab.com/openrtb

Page 53

OpenRTB API Specification Version 2.5

IAB Technology Lab

6. Bid Request/Response Samples
6.1

GitHub Repository

The official OpenRTB Github repository now contains a set of validated example requests. This
repository should be considered the canonical examples for implementers.
github.com/openrtb/examples

6.2

Validator

An OpenRTB Validator has been developed to test compliance of bid response and bid response JSON
payloads. The Validator is available for all final versions of OpenRTB specification. The code for thevalidator is distributed freely under a BSD-3 open source license at the below URL.
github.com/openrtb/openrtb2x/tree/2.0/openrtb-validator

6.3

Bid Requests

6.3.1 Example 1 – Simple Banner
Following is a basic example of a bid request for a banner ad. Some optional parameters are included inthis example.
{"id": "80ce30c53c16e6ede735f123ef6e32361bfc7b22","at": 1, "cur": [ "USD" ],"imp": [{"id": "1", "bidfloor": 0.03,"banner": {"h": 250, "w": 300, "pos": 0}}],"site": {"id": "102855","cat": [ "IAB3-1" ],"domain": "www.foobar.com","page": "http://www.foobar.com/1234.html ","publisher": {"id": "8953", "name": "foobar.com","cat": [ "IAB3-1" ],"domain": "foobar.com"}},"device": {www.iab.com/openrtb

Page 54

OpenRTB API Specification Version 2.5

IAB Technology Lab"ua": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/537.13(KHTML, like Gecko) Version/5.1.7 Safari/534.57.2","ip": "123.145.167.10"},"user": {"id": "55816b39711f9b5acf3b90e313ed29e51665623f"}}

6.3.2 Example 2 – Expandable Creative
This example builds the first and adds parameters to describe support for an expandable creative, andpasses data about the user from “Data Provider 1”.
{"id": "123456789316e6ede735f123ef6e32361bfc7b22","at": 2, "cur": [ "USD" ],"imp": [{"id": "1", "bidfloor": 0.03,"iframebuster": [ "vendor1.com", "vendor2.com" ],"banner": {"h": 250, "w": 300, "pos": 0,"battr": [ 13 ],"expdir": [ 2, 4 ]}}],"site": {"id": "102855","cat": [ "IAB3-1" ],"domain": "www.foobar.com","page": "http://www.foobar.com/1234.html","publisher": {"id": "8953", "name": "foobar.com","cat": [ "IAB3-1" ],"domain": "foobar.com"}},"device": {"ua": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/537.13(KHTML, like Gecko) Version/5.1.7 Safari/534.57.2","ip": "123.145.167.10"},"user": {"id": "55816b39711f9b5acf3b90e313ed29e51665623f","buyeruid": "545678765467876567898765678987654","data": [{"id": "6", "name": "Data Provider 1","segment": [{www.iab.com/openrtb

Page 55

OpenRTB API Specification Version 2.5

IAB Technology Lab"id": "12341318394918", "name": "auto intenders"},{"id": "1234131839491234", "name": "auto enthusiasts"},{"id": "23423424", "name": "data-provider1-age","value": "30-40"
}
]
}
]
}
}

6.3.3 Example 3 – Mobile
This example uses a device object to reflect a mobile device, and an app object to reflect a request froma mobile application.
{"id": "IxexyLDIIk","at": 2,
"bcat": [ "IAB25", "IAB7-39", "IAB8-18", "IAB8-5", "IAB9-9" ],"badv": [ "apple.com", "go-text.me", "heywire.com" ],"imp": [{"id": "1", "bidfloor": 0.5, "instl": 0,"tagid": "agltb3B1Yi1pbmNyDQsSBFNpdGUY7fD0FAw","banner": {"w": 728, "h": 90, "pos": 1,"btype": [ 4 ],"battr": [ 14 ],"api": [ 3 ]}}],"app": {"id": "agltb3B1Yi1pbmNyDAsSA0FwcBiJkfIUDA", "name": "Yahoo Weather","cat": [ "IAB15", "IAB15-10" ],"ver": "1.0.2","bundle": "12345","storeurl": "https://itunes.apple.com/id628677149","publisher": {"id": "agltb3B1Yi1pbmNyDAsSA0FwcBiJkfTUCV", "name": "yahoo","domain": "www.yahoo.com"}},"device": {"dnt": 0,"ua": "Mozilla/5.0 (iPhone; CPU iPhone OS 6_1 like Mac OS X)
AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A334 Safari/7534.48.3",

www.iab.com/openrtb

Page 56

OpenRTB API Specification Version 2.5

IAB Technology Lab"ip": "123.145.167.189","ifa": "AA000DFE74168477C70D291f574D344790E0BB11","carrier": "VERIZON","language": "en","make": "Apple", "model": "iPhone","os": "iOS", "osv": "6.1","js": 1,"connectiontype": 3,"devicetype": 1,"geo": {"lat": 35.012345, "lon": -115.12345,"country": "USA","metro": "803","region": "CA", "city": "Los Angeles", "zip": "90049"}},"user": {"id": "ffffffd5135596709273b3a1a07e466ea2bf4fff","yob": 1984, "gender": "M"}}

6.3.4 Example 4 – VideoThe following example illustrates a bid request for a video impression with two companion ad slots (1expandable). Additionally, the video content itself is described in the "content" object. A few notes
about specific fields in the example:
protocols: Only VAST 2.0 and 3.0 are allowed. Note that a wrapper response is not allowed inthis example.
sequence: It is not explicitly included so the default of “1” should be assumed.
battr: User interactive and alert type ads (value “13” and “14”, respectively) are explicitly being
blocked for both the video and its companions.
pos: Indicates this opportunity is “above the fold”.
api: Indicates that VPAID 1.0 containers are explicitly supported. As such, the mime types
supported for VPAID are only “application/x-shockwave-flash” and “application/javascript”. Notethat there is an implicit restriction as to which protocol is allowed in which mime type. JavaScript
support was not specified until VPAID 2.0, while Flash supports both VPAID 1.0 and 2.0.
companiontype: Indicates only static or HTML resources are allowed.








{
"id": "1234567893","at": 2, "tmax": 120,
"imp": [{"id": "1", "bidfloor": 0.03,"video": {"w": 640, "h": 480, "pos": 1,"startdelay": 0, "minduration": 5, "maxduration": 30,

www.iab.com/openrtb

Page 57

OpenRTB API Specification Version 2.5

IAB Technology Lab"maxextended": 30,"minbitrate": 300, "maxbitrate": 1500,"api": [ 1, 2 ],"protocols": [ 2, 3 ],"mimes": ["video/x-flv","video/mp4","application/x-shockwave-flash","application/javascript"],"linearity": 1,"boxingallowed": 1,"playbackmethod": [ 1, 3 ],"delivery": [ 2 ],"battr": [ 13, 14 ],"companionad": [{"id": "1234567893-1","w": 300, "h": 250, "pos": 1,"battr": [ 13, 14 ],"expdir": [ 2, 4 ]},{"id": "1234567893-2","w": 728, "h": 90, "pos": 1,"battr": [ 13, 14 ]}],"companiontype": [ 1, 2 ]}}],"site": {"id": "1345135123", "name": "Site ABCD","domain": "siteabcd.com","cat": [ "IAB2-1", "IAB2-2" ],"page": "http://siteabcd.com/page.htm","ref": "http://referringsite.com/referringpage.htm","privacypolicy": 1,"publisher": {"id": "pub12345", "name": "Publisher A"},"content": {"id": "1234567","series": "All About Cars","season": "2", "episode": 23, "title": "Car Show","cat": [ "IAB2-2" ],"keywords": "keyword-a,keyword-b,keyword-c"}},"device": {"ip": "64.124.253.1","ua": "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.16)
Gecko/20110319 Firefox/3.6.16",

www.iab.com/openrtb

Page 58

OpenRTB API Specification Version 2.5

IAB Technology Lab"os": "OS X","flashver": "10.1", "js": 1},"user": {"id": "456789876567897654678987656789","buyeruid": "545678765467876567898765678987654","data": [{"id": "6", "name": "Data Provider 1","segment": [{"id": "12341318394918", "name": "auto intenders"},{"id": "1234131839491234", "name": "auto enthusiasts"
}
]
}
]
}
}

6.3.5 Example 5 – PMP with Direct Deal
Following is a basic example of a bid request for a banner ad with a direct deal. Some optionalparameters are included in this example.
{"id": "80ce30c53c16e6ede735f123ef6e32361bfc7b22","at": 1, "cur": [ "USD" ],"imp": [{"id": "1", "bidfloor": 0.03,"banner": {"h": 250, "w": 300, "pos": 0},"pmp": {"private_auction": 1,"deals": [{"id":"AB-Agency1-0001","at": 1, "bidfloor": 2.5,
"wseat": [ "Agency1" ]},{"id":"XY-Agency2-0001","at": 2, "bidfloor": 2,"wseat": [ "Agency2" ]}]}}www.iab.com/openrtb

Page 59

OpenRTB API Specification Version 2.5

IAB Technology Lab],"site": {"id": "102855","domain": "www.foobar.com","cat": [ "IAB3-1" ],"page": "http://www.foobar.com/1234.html","publisher": {"id": "8953", "name": "foobar.com","cat": [ "IAB3-1" ],"domain": "foobar.com"}},"device": {"ua": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/537.13(KHTML, like Gecko) Version/5.1.7 Safari/534.57.2","ip": "123.145.167.10"},"user": {"id": "55816b39711f9b5acf3b90e313ed29e51665623f"}}

6.3.6 Example 6 – Native Ad
Following is a basic example of a bid request for a Native ad; similar otherwise to the simple banner
example in Section 6.3.1. Notice the request attribute in the Native object contains an encoded
string of a native ad request that conforms to the Dynamic Native Ads API, specifically version 1.0 as
indicated by the ver attribute.
Notice that the contents of the request attribute is a JSON encoded string of the Dynamic Native Ads
request including its native top level object. This necessitates separate parsing steps for the outer
OpenRTB structure and the Dynamic Native Ads request payload in order to enforce a separation ofthese specifications. The goal of this is to enable independent evolution of these specifications while
avoiding the need to implement parsers for each pairwise combination thereof or to write custom JSON
parsers.
{"id": "80ce30c53c16e6ede735f123ef6e32361bfc7b22","at": 1, "cur": [ "USD" ],"imp": [{"id": "1", "bidfloor": 0.03,"native": {"request": "{\"native\":{\"ver\":\"1.0\",\"assets\":[ ... ]}}","ver": "1.0","api": [ 3 ], "battr": [ 13, 14 ]}}],"site": {"id": "102855",

www.iab.com/openrtb

Page 60

OpenRTB API Specification Version 2.5

IAB Technology Lab"cat": [ "IAB3-1" ],"domain": "www.foobar.com","page": "http://www.foobar.com/1234.html ","publisher": {"id": "8953", "name": "foobar.com","cat": [ "IAB3-1" ],"domain": "foobar.com"}},"device": {"ua": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/537.13(KHTML, like Gecko) Version/5.1.7 Safari/534.57.2","ip": "123.145.167.10"},"user": {"id": "55816b39711f9b5acf3b90e313ed29e51665623f"
}
}

6.4

Bid Responses

6.4.1 Example 1 – Ad Served on Win Notice
Following is an example of a bid response with the ad served on win notice. The bid for this impression
is a $9.43 CPM.
{
"id": "1234567890", "bidid": "abc1123", "cur": "USD","seatbid": [{"seat": "512","bid": [{"id": "1", "impid": "102", "price": 9.43,"nurl": "http://adserver.com/winnotice?impid=102","iurl": "http://adserver.com/pathtosampleimage","adomain": [ "advertiserdomain.com" ],"cid": "campaign111","crid": "creative112","attr": [ 1, 2, 3, 4, 5, 6, 7, 12 ]
}
]
}
]
}

6.4.2 Example 2 – VAST XML Document Returned Inline
Following is an example of a bid response that returns the VAST document inline to be served. A few
notes about specific fields in the example:
www.iab.com/openrtb

Page 61OpenRTB API Specification Version 2.5

IAB Technology Lab

The bid for this impression is a $3.00 CPM.



Note that since there both a win notice URL and an inline VAST document in the adm attribute,which constitutes the ad markup. The win notice is still called, but if it were to return markup it
would be ignored in favor of the contents of the adm attribute.

{"id": "123","seatbid": [{"bid": [{"id": "12345", "impid": "2", "price": 3.00,"nurl": "http://example.com/winnoticeurl","adm": "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n<VAST
version=\"2.0\">\n<Ad id=\"12345\">\n<InLine>\n<AdSystemversion=\"1.0\">SpotXchange</AdSystem>\n<AdTitle>\n <![CDATA[Sample
VAST]]>\n</AdTitle>\n<Impression>http://sample.com</Impression>\n<Description>\n<![CDATA[A sample VAST feed]]>\n</Description>\n <Creatives>\n<Creative sequence=\"1\"
id=\"1\">\n<Linear>\n<Duration>00:00:30</Duration>\n <TrackingEvents></TrackingEvents>\n<VideoClicks>\n<ClickThrough>\n<![CDATA[http://sample.com/openrtb
test]]>\n</ClickThrough>\n</VideoClicks>\n<MediaFiles>\n<MediaFile
delivery=\"progressive\" bitrate=\"256\" width=\"640\" height=\"480\"
type=\"video/mp4\">\n<![CDATA[http://sample.com/video.mp4]]>\n</MediaFile>\n</MediaFiles>\n</Linear>\n</Creative>\n</Creatives>\n</InLine>\n</Ad>\n</VAST>"
}
]
}
]
}

6.4.3 Example 3 – Direct Deal Ad Served on Win Notice
Following is an example of a bid response with the ad served on win notice. The bid for this impression
is a $5.00 CPM against a direct deal.
{"id": "1234567890", "bidid": "abc1123", "cur": "USD","seatbid": [{"seat": "512","bid": [{"id": "1", "impid": "102", "price": 5.00,"dealid": "ABC-1234-6789","nurl": "http: //adserver.com/winnotice?impid=102","adomain": [ "advertiserdomain.com" ],"iurl": "http: //adserver.com/pathtosampleimage","cid": "campaign111","crid": "creative112",

www.iab.com/openrtb

Page 62OpenRTB API Specification Version 2.5

IAB Technology Lab"adid": "314","attr": [ 1, 2, 3, 4 ]
}
]
}
]
}

6.4.4 Example 4 – Native Markup Returned Inline
Following is an example of a bid response that returns a native ad inline to be served. The adm attributecontains an encoded string of a native ad request that conforms to the Dynamic Native Ads API andspecifically the same version as that used for the request string. Alternatively, the adm attribute could
have been omitted in favor of returning the native ad markup in the response to the win notice nurl.

{"id": "123","seatbid": [{"bid": [{"id": "12345", "impid": "2", "price": 3.00,"nurl": "http://example.com/winnoticeurl","adm": "{\"native\":{\"ver\":\"1.0\",\"link\":{ ... },\"imptrackers\":[ ... ],\"assets\":[ ... ]}}"
}
]
}
]
}

www.iab.com/openrtb

Page 63

OpenRTB API Specification Version 2.5

IAB Technology Lab

7. Implementation Notes
The following section will provide brief notes on how certain objects and fields are to be interpreted andimplemented.

7.1

No-Bid Signaling

This section covers best practices for using the optional no-bid signaling. See the List 5.24 for theenumerated list of no-bid reason codes.
Many exchanges support multiple response types as a no-bid:HTTP 204 “No Content” from the bidder (most economical in terms of bandwidth).
An empty JSON object:{}A well-formed no bid response:{"id": "1234567890", "seatbid": []}A well-formed no bid response with a reason code:{"id": "1234567890", "seatbid": [], "nbr": 2}

An important issue in RTB is when impressions are triggered by software robots mimicking web
browsers. Such robots may be implicitly or explicitly driving these false transactions. The following
represents a set of symmetric best practices for exchanges and bidders to help recognize and reject
these events.

Responsibility of the exchange
Make best effort to classify and reject “non-human traffic” requests for ads to the exchange via thefollowing best practices:

(Recommended) Filter impressions from known spiders via user-agent classification.
(Recommended) Filter impressions from suspected NHT via a “detector”.

Responsibility of the bidder(Recommended) no-bid impressions from known spiders via user-agent classification.
(Recommended) no-bid impressions from suspected NHT via a “detector”.
Specify a no-bid reason code in either case.

Where:For exchanges, filtering the impression means that the exchange should respond to the “ad call”
with either a blank HTTP 204 response or an unpaid ad (PSA) and not offered to any bidders.
For bidders, filtering the impression means that the bidder should respond with a no-bid.
For both exchanges and bidders, the impression transaction records should be clearly marked in any
logging systems and be removed from contributing to any event counts associated with planning,
forecasting, and reporting systems.

www.iab.com/openrtb

Page 64OpenRTB API Specification Version 2.5

7.2

IAB Technology Lab

Impression Expiration

Recapping the typical impression flow through RTB, an ad will be requested by a client (e.g., webbrowser, mobile app or an SDK therein) possibly through other server intermediaries, and ultimately to
the RTB exchange. The exchange conducts an auction among buyers who bid with a proposed price,
possibly markup for use if the bid wins (markup can also be delivered on the win notice itself), and othermetadata about the bid. The exchange then selects a winner, issues a win notice to the winning bidder,and passes the markup back to the client.
Winning the auction, however, does not guarantee that the ad will be successfully delivered to the clientor that it will meet viewability expectations. Furthermore, policies vary among exchanges as to thecriteria for billing. Most consider an ad billable upon some form of delivery or rendering vs. the auction
win alone. This aligns better with the buyer’s obvious goal of ensuring that the impressions they pay forare actually displayed.
Some exchanges attempt to facilitate this alignment by placing the win notice in the winning ad markup
so that it can serve as both a win notice and rendering notice. This is neither endorsed nor prohibitedby OpenRTB except that it precludes the exchange from accepting markup on the win notice return as
described in Section 4.3.1. Similarly, many buyers use their own tracking URL placed within their admarkup to signal rendering independent of the OpenRTB auction win notice. In video specifically, VAST
supports an impression tracking URL that is often used for billing and is always distinct from the auction
win notice.
To abstract the concept, let us refer to “billing notice” as the firing of some notification URL at the time
when the clearing price of the impression will be booked as spend. This is irrespective of whether theactual OpenRTB win notice URL is delegated to the client for firing or some other tracking URL is used.
For buyers, this billing notice is used to book progress toward spend goals and frequency caps and drive
pacing algorithms. When the billing notice is delayed significantly, these critical functions can beseriously impaired. There are legitimate reasons for some delays such as caching. A common scenario isa video interstitial impression in a mobile app. Refining the example, consider a game where the video
is prefetched during game play so that it can be shown after the current game level ends. This isimportant for the user experience, but can delay the rendering of the ad for many minutes.
Bidders are strongly advised to track the time between the auction and the win and/or billing notices toensure reasonable delays. If unreasonable delays are encountered frequently, bidders may elect toignore such events and bring them to the attention of the exchange for resolution. Unfortunately, thesequence from ad request through the auction and finally to rendering and billing is fundamentally nottransactional. There are simply too many parties, policies, and technologies involved and thus a good
support relationship between exchange and buyer is still important.
The OpenRTB protocol does provide some real-time assistance, however. The imp.exp attribute(Section 3.2.4) in the bid request allows an exchange to provide guidance to bidders of the number of
seconds that may elapse between the auction and the billing event. As usual, omitted means unknown.
Bidders can then decide if they want to bid understanding the likely delay. Bidders are advised,however, to interpret this as guidance as opposed to a contract unless the exchange expresses
otherwise since exchanges are not always in a position to make hard guarantees (e.g., the SDK within
the client app may not be under the exchange’s control).
Similarly, the bid.exp attribute (Section 4.2.3) in the bid response allows the bidder to express the
maximum number of seconds they are willing to tolerate between auction and billing notice. This allows

www.iab.com/openrtb

Page 65

OpenRTB API Specification Version 2.5

IAB Technology Lab

the exchange to drop bids with expiration constraints it believes are likely to be violated. Bidders should
not assume that a delayed billing notice greater than their specified bid expirations will not be billable.
That is a policy and contract discussion between bidder and exchange and not imposed by OpenRTB.
The following expiration times are offered as examples of reasonable delays based on the nature of theimpression. These are only provided as rules of thumb. A more data-driven method of determining
these times in specific situations is highly recommended.






Desktop and mobile web browsers:
Mobile app banner ads that may be cached:
Mobile app native ads that may be cached:
Mobile and video interstitials:
Audio or video with server-side stitching:

7.3

1 Minute
5 Minutes
10 Minutes
30 Minutes (or even longer)
Very Long or Unknown

PMP & Direct Deals

Best Practice Bidding Logic
Receive request and parse;
Create empty bid list for response;
If request contains the impression[].pmp object;match bids against each pmp.deals[];
enforce targeting for dealID and seatID;
append best M matching bids to response;
If pmp.private_auction = False;
match open auction bids against the request;
append top N bids by price to response;
Return response list to exchange;

RecommendationsM >= 1, preferably one per matching Deal ID.
N >= 2 to assist with blocking rate issues.
Minimum viable is “1+1” bidding.
Ideal is “M+N” bidding.

Warning
Returning only one bid when both Deal ID and open auction bids are valid creates problems. The
exchange side may be configured by a publisher to prioritize all Deal ID bids above open auction bids, orto force a price auction between them with different floors by class of bid. There are multiple common
practices that depend on how the publisher prefers to sell inventory with Deal ID.

www.iab.com/openrtb

Page 66

OpenRTB API Specification Version 2.5

IAB Technology Lab

Policy Recommendations


A Deal ID should be utilized for any situation where the auction may be awarded to a bid not on thebasis of price alone. Any prioritization of bids other than by price should have a Deal ID.
A Deal ID is recommended for all situations where a preferential floor may be assigned to a seat
entity.

Anti-Patterns
The below is a set of anti-patterns that OpenRTB supporting platforms have observed in various
attempts to implement Deal ID bidding logic.

Subjecting Deal ID Bids to an internal auction on price
The ideal bidding logic describes a process of being liberal about sending bids. Deal ID bids may not be
subject to a classic price auction. There may be an expectation that the buyer and seller wantprioritization to achieve a larger objective: complete delivery of the Deal represented by the Deal ID.
Thus any bidding logic that sorts Deal ID bids by price (with or without open marketplace bids) andtruncates the list too aggressively can endanger the fulfillment of the Deal.

Associating Deal ID to the wrong Object
A Deal ID should be treated as a “targeting token” associated to orders, line-items or campaigns. If theDeal ID is associated to a Seat/Buyer it may create an undesired application of the Deal ID too many
active campaigns. Alternatively if it is associated to the Advertiser it may limit that entity to only a single
Deal ID.

Improper Handling of the Private vs Open Market Flag
The pmp.private_auction flag indicates that the seller is willing or not willing to accept open market
bids (i.e., “all bidders are welcome”). If this flag is not read and interpreted correctly, bid responses may
be invalid. Open market bids sent to a private impression auction may be rejected and should not havebeen exposed to all bidders.

Improper handling of Seat IDs
If Seat IDs are treated as a filter of eligible demand partners on an open market impression, this defeats
the “all bidders are welcome” intention.

Silently Applying Margin Discounts to Deal ID Bids
With Deal ID buyers are sellers are communicating directly. The Exchange and Bidder become thirdparty automation platforms. If there are any automatic or silent discounts of bid prices (based upon
margins or fees) set by either the exchange or the bidder, then the Deal may fail to function correctly.

www.iab.com/openrtb

Page 67OpenRTB API Specification Version 2.5

IAB Technology Lab

Use cases
Case-1: Open Trading Agreement with Buyer












Between publisher and buying entity.
Publisher sets an access rule defining the price floor for a specific buyer.
Locked to the buyer.
Broadcast price floor.
Public/open inventory.
No Deal ID needed (Deal ID is optional).
No named advertiser(s).
No prioritization of bids.
Daily total or frequency caps optional on publisher/exchange side.
All placements or limited to specific placements.
Targeting is up to the buyer/bidder.

Case-2: Open Trading Agreement with Buyer with Named AdvertisersAs Case-1 with a list of named advertisers.

Case-3: Open Bidding with Deal ID as Value-added Markers









Between publisher and buying entity.
Publisher sets a price floor for URL masked inventory.
Public/open inventory (i.e., all buyers welcome).
Deal ID represents “Package Tokens”.
Each Deal ID signals that the impression falls into various content and placement categories.
Floor is associated to each Deal ID to signal cost for usage of that token.
Winner is decided by bid price.
Execution of targeting is up to the buyer/bidder.

Case-4: First Look Trading Agreement











Between publisher and buying entity.
Publisher sets an access rule defining the price floor for the buyer.
Locked to the buyer.
Known price floor.
Deal ID needed.
Optional named advertiser list.
Prioritization of bids expected.
Daily total or frequency caps optional on publisher/exchange side.
All placements or limited to specific placements.
Targeting is up to the buyer/bidder.

Case-5: Direct Option Deal with Advertiser via RTB






Between Publisher and Advertiser or their representative.
Publisher sets a rule defining a price floor and prioritization for specific advertiser(s).
Fill rate is expected to be greater than or equal to X%.
Locked to the buyer.
Private/exclusive inventory.

www.iab.com/openrtb

Page 68OpenRTB API Specification Version 2.5









IAB Technology Lab

Limited to a set list of advertiser names (generally variants of one name).
Known price floor.
Deal ID needed.
Prioritization of bids expected.
Daily total or frequency caps will apply on bidder side; optional on Exchange side.
Limited to specific placements.
Targeting is mostly enforced by buyer/bidder.

Case-6: Direct Option Deal with Advertiser via RTB with Private Data••

Same as Case-4.
Deal ID represents some combination of private first-party data from the Publisher.

Case-7: Full-Fill Direct Deal with Advertiser via RTB••

Same as Case-4.
Fill rate is expected to be 100% or nearly so.

Case-8: Full-Fill Direct Deal with Advertiser via RTB with Private Data
•
•

7.4

Same as Case-6.
Deal ID represents some combination of private first-party data from the Publisher.

Skippability

This section clarifies the common use cases related to declaring skippability of video creatives.
Under most circumstances for RTB transactions, publishers and exchanges prefer to control the ability toskip the ad. OpenRTB therefore assumes by default that a standard linear video ad can be used as the
response to a skippable request and the ability to skip the ad will be provided by the supplier’s player
automatically.
The presence of the video.skip attribute in the bid request with a value of “1” should be assumed tomean that the publisher will impose a skip button on the ad. The absence of the video.skip attributeshould be assumed to mean that it is unknown whether the publisher will impose a skip button.
DSPs should confirm with publishers whether it is permissible to respond with ads that provide theirown skip functionality (e.g., using VPAID to render a skip button). If bidding with such an ad and only ifdoing so, the bid must indicate creative attribute “16” using the attr array in the bid response.
Note: VAST 4.0 separates VPAID interactivity from the media file so this is deprecated and only applies
to earlier versions of VAST.
Some examples of these concepts follow:

www.iab.com/openrtb

Page 69

OpenRTB API Specification Version 2.5

IAB Technology Lab

Bid Request
Case-1: Skippable after N Seconds for All Creatives
In this case, the publisher will impose skippability. All ads will be skippable, but only after 5 seconds ofplay. Creatives with a total duration of 5 seconds or less would not be skippable since they would neverreach this threshold.
"video": {..., "skip": 1, "skipafter": 5, ...
}Case-2: Skippable after N Seconds for Minimum Duration Creatives
In this case, the publisher will impose skippability. However, only creatives with a total duration greaterthan 15 seconds will be skippable. For ads that satisfy this minimum total duration, skippability isenabled after 5 seconds of play. Note that although these values are integers, they will compare as
precise values with actual video durations. For example, a video with duration 15.1 seconds does satisfy
a skipmin value of 15 (i.e., think of the skipmin value as being 15.0).
"video": {..., "skip": 1, "skipmin": 15, "skipafter": 5, ...
}Case-3: Non-Skippable unless Requested by the Ad Markup
In this case, the publisher will not impose skippability. Ads will only be skippable if requested by the admarkup. This is supported by VPAID and VAST 3.0, for example.
"video": {..., "skip": 0, ...
}Case-4: Unknown Skippability
In this case, the skip attribute is omitted which indicates that exchange does not know if skippability
will be imposed by the publisher. This may be the case, for example, when the exchange is not an SSP
and thus may not have control or full knowledge of the publisher’s intentions.

Bid Response
Consider Case-3 above, where the publisher does not impose skippability. If the ad markup itself will
request skippability (e.g., via VPAID or VAST 3.0), then the bid must signal this intention. This isaccomplished by including creative attribute 16 (i.e., Skippable) in the bid as shown below. If themarkup is not going to request skippability, then this creative attribute should not be indicated.

www.iab.com/openrtb

Page 70

OpenRTB API Specification Version 2.5

IAB Technology Lab

When responding to Case-3 with this skippable attribute specified in the bid, the publisher should
provide skippability either by instructing the VAST 3.0 player to activate skippability (refer to the VAST
3.0 “skipoffset” attribute) or by allowing the ad to render its own skip button using VPAID.
"bid": {..., "attr": [16], ...
}In Case-1 and Case-2 where the publisher may impose its own skippability, creative attribute 16 should
not be specified. Furthermore, publishers are advised to filter responses containing attribute 16 since
this could conflict with the skip button rendered by the publisher. When using a VAST 3.0 response,
publishers may choose to implement support for VAST 3.0 “skipoffset” at their discretion and ads should
be assumed to play non-skippable if the player does not support it.

7.5

COPPA Regulation Flag

The United States Federal Trade Commission has changed the compliance rules for the Children’s Online
Privacy Protection Act (“COPPA”), effective July 1, 2013. The proposal effects websites, and associatedservices), that have been identified as: (1) directed to users under 13 years of age; or (2) collecting
information from users actually known to be under 13 (collectively “Children’s Sites”).
The FTC has written a comprehensive FAQ on the change here:
www.ftc.gov/tips-advice/business-center/guidance/complying-coppa-frequently-asked-questions
Steve Bellovin, CTO of the FTC, argued for a standardized signaling protocol in a blog posted dated
January 2013:www.ftc.gov/news-events/blogs/techftc/2013/01/coppa-signaling

Impacts
The FAQ specifically calls out these areas relevant for OpenRTB as “Personal Information” that is not tobe collected:
Geo-location information sufficient to identify street name and name of a city or town.
Persistent identifiers when they can be used to recognize a user over time and across different Web
sites or online services.

Recommendations to Implementers
OpenRTB Exchanges and Bidders should:






Provide a facility for sites to be declared as “child directed”.
Implement the regulations object extension.
Provide facilities within campaigns to target for and against this signal.
Degrade the Geographic information to be less exact prior to logging or transmission.
Suppress the assignment and synchronization of identifiers, depending on usage.

www.iab.com/openrtb

Page 71OpenRTB API Specification Version 2.5

IAB Technology Lab

It is recommended that when regs.coppa = 1, the exchange should additionally manipulate the
OpenRTB bid request object as follows:

Device Object
Suppress didmd5 and didsha1 device ID fields.



Truncate ip field - remove lowest 8 bits.
Truncate ipv6 field - remove lowest 32 bits.

Geo Object
Suppress lat and lon fields.
Suppress metro, city, and zip fields.

User Object
Suppress id, buyeruid, yob, and gender fields.

www.iab.com/openrtb

Page 72

OpenRTB API Specification Version 2.5

IAB Technology Lab

Appendix A. Additional InformationCreative Commons / Attribution License
creativecommons.org/licenses/by/3.0



IAB (Interactive Advertising Bureau)
www.iab.com



IAB Quality Assurance Guidelines (QAG):
www.iab.com/guidelines/iab-quality-assurance-guidelines-qag-taxonomy/

JavaScript Object Notation (JSON)
www.json.org



MMA (Mobile Marketing Association)
mmaglobal.com



OpenRTB Project on Github
github.com/openrtb/OpenRTB/Apache Avro
avro.apache.org

Protocol Buffers (Protobuf)
code.google.com/p/protobuf



Google Metro Codes
code.google.com/apis/adwords/docs/appendix/metrocodes.html



U.N. Code for Trade and Transport Locations:www.unece.org/cefact/locode/service/location.htm

www.iab.com/openrtb

Page 73

OpenRTB API Specification Version 2.5

IAB Technology Lab

Appendix B. Specification Change Log
This appendix serves as an index of specification changes from v2.4 to v2.5. These changes pertain only
to the substance of the specification and not routine document formatting, organization, or content
without technical impact.
SectionDescription

2.4

Section: Data Encoding
New section added.

3.1

Object Model: Bid Request
Updated to include Source and Metric objects.

3.2.1

Object: BidRequest
Attributes bseat, wlang, and source have been added.

3.2.2

Object: Source
New Source object has been added including the Payment ID pchain attribute.

3.2.4

Object: Imp
Attribute metric has been added.

3.2.5

Object: Metric
New Metric object has been added.

3.2.6

Object: Banner
Attribute vcm has been added.

3.2.7

Object: Video
Attributes placement and playbackend have been added. Guidance added to use only the
first element of attribute playbackmethod in preparation for future conversion to an integer.

3.2.10Object: Format
Attributes wratio, hratio, and wmin have been added.

3.2.13

Object: Device
Attribute mccmnc has been added. Attribute carrier has been clarified to eliminate areference to using “WIFI” as a carrier.

4.2.3

Object: Bid
Attributes burl, lurl, tactic, language, wratio, and hratio have been added.

4.4

Substitution Macros:
Macros ${AUCTION_MBR} and ${AUCTION_LOSS} have been added. A best practice has been
added to use “AUDIT” for unknown values when rendering for test or quality purposes.

5.6

List: API Frameworks
Item 6 has been added.

5.9

List: Video Placement Types
New list has been added.

5.10

List: Playback Methods
Items 5-6 have been added.

www.iab.com/openrtb

Page 74OpenRTB API Specification Version 2.5

SectionDescription

5.11

List: Playback Cessation Modes

IAB Technology Lab

New list has been added.
5.24

List: No-Bid Reason Codes
Items 9-10 have been added.

5.25

List: Loss Reason Codes
New list has been added.

www.iab.com/openrtb

Page 75