Agency Echelon
Reference

Standards

The technical specifications and measurement definitions that digital advertising runs on. Most are published by the IAB Tech Lab and the Media Rating Council; the rest come from the platforms that control a layer of the stack.

StandardPublished byWhat it does
OpenRTBIAB Tech LabProtocol for bid requests and responses in real-time bidding. Version 2.6 is the deployed standard; 2.6 added CTV and podcast fields and the durable identifier extensions. Every programmatic transaction on the open web is an OpenRTB conversation.
VAST 4.xIAB Tech LabXML template for delivering video ads to players, with tracking events, media files, and support for server-side ad insertion, mezzanine files, and Open Measurement. VPAID is deprecated; SIMID replaces it for interactive video.
Open Measurement (OMID)IAB Tech LabSDK and interface that lets verification vendors measure viewability and invalid traffic in apps and CTV without vendor-specific code.
ads.txt and app-ads.txtIAB Tech LabPublisher-published list of authorized sellers, checked by buyers to reject unauthorized inventory and spoofed domains.
sellers.json and SupplyChain objectIAB Tech LabSeller-published identification of every party they represent, and the OpenRTB object that carries the full path of intermediaries in each bid request.
Transparency and Consent Framework 2.2IAB EuropeStandard for capturing GDPR consent and transmitting it through the supply chain as a TC String. Required by Google for EEA and UK monetization.
Global Privacy PlatformIAB Tech LabSingle string carrying privacy signals across US state laws, Canada, and the European TCF section. Successor to the US Privacy String.
Global Privacy ControlGPC working groupBrowser signal for opting out of sale and sharing, legally binding under California and several other state laws.
IAB Content Taxonomy 3.0IAB Tech LabStandard categories for classifying content, used for contextual targeting and brand suitability.
Audience Taxonomy 1.1IAB Tech LabStandard categories for describing audience segments across data providers.
Fixed and Flexible Ad SpecificationsIAB Tech LabStandard display ad sizes, aspect ratios, and file weight limits (the LEAN principles).
MRC Viewable Impression GuidelinesMedia Rating CouncilDefinition of a viewable impression: 50 percent of pixels for one continuous second (display) or two seconds (video); 100 percent for large canvas units.
MRC Invalid Traffic Detection and Filtration GuidelinesMedia Rating CouncilStandards for detecting and removing general and sophisticated invalid traffic from counted impressions.
GARM Brand Safety Floor and Suitability FrameworkWorld Federation of AdvertisersCommon definitions of unsafe content categories and four risk levels for suitability. GARM itself was discontinued in 2024; the framework remains in use by verification vendors and platforms.
IAB/4A's Standard Terms and Conditions 3.0IAB and 4A'sDefault contract terms for US digital media insertion orders: cancellation, discrepancies, makegoods, data use, and payment.
SKAdNetwork and AdAttributionKitApplePrivacy-preserving install attribution for iOS; postbacks are delayed, aggregated, and limited in detail.
Privacy Sandbox APIsGoogleTopics, Protected Audience, and Attribution Reporting APIs in Chrome; Privacy Sandbox on Android. Scope reduced after Google dropped third-party cookie deprecation in 2025.
Unified ID 2.0The Trade Desk (open source)Email- and phone-based encrypted identifier for addressable advertising without third-party cookies.
Prebid.jsPrebid.orgOpen-source header bidding wrapper and the de facto standard for publisher-side auctions.
Ad Product Taxonomy and Ad Management APIIAB Tech LabStandards for describing ad products and creative approval workflows between DSPs and SSPs.

Terms used above are defined in the infrastructure section of the glossary.

Reference

A reference library for digital advertising, written and reviewed by the Agency Echelon team. Free to read. No advertising, no sponsorship, no affiliate links, no email gate.

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Reviewed September 23, 2026. Reference text is licensed CC BY 4.0. Privacy