Blog

OpenRTB news and analysis

What changed in the spec, what IAB Tech Lab is shipping, and what each development means for the people who maintain bid streams. Reference material lives in the docs; this is the timely layer on top. RSS feed.

CTV

Fraudulent CTV bundle IDs mimic each platform's ID grammar. OpenRTB validates shape, not spoof.

Analysis of the 50 highest-traffic fraudulent CTV bundle IDs finds brand spoofing on Roku, ASIN-style mimicry on Fire TV, numeric ID mimicry on Samsung, and mobile bundles in CTV streams. A well-formed app.bundle passes schema checks while the identity claim is false.

CTV

A CTV app delisted from the store can still bid. The auction keys on bundle ID, not shelf status.

Pixalate's August 2026 CTV pre-bid blocklist flags apps removed from stores that continue generating programmatic traffic. Impression-level IVT does not catch that gap; app-level exclusion does, because OpenRTB never carries whether the store still lists the bundle.

Agentic

OpenRTB has two JSON encodings, and ARTF's own sample corpus uses both

The OpenRTB specification types 28 flag fields as integers. The IAB OpenRTB protobuf schema declares those same fields bool. Both encodings are in the wild, a payload valid in one is invalid in the other, and two of the five ARTF reference samples cannot be parsed by the protobuf JSON parser the framework runs on.

Supply chain

SupplyChain v1.1 adds nodes that never touch the money. Most schain checks assume those cannot exist.

The proposed upgrade puts technical custody entities into the main chain with hp=0, bumps ver, and reworks what complete means. Public comment closes August 21. What that does to hop counting, sellers.json cross-checks, and every validator that treats hp=1 as an invariant.

Agentic

The agentic protocols shipped a version handshake. A bid request still has nowhere to say which OpenRTB it is.

AdCP 3.1 puts a version on every request and response, advertises supported releases, and returns a typed error when a buyer pins one the seller does not serve. AAMP 2.3 added trust verification on price-moving paths. OpenRTB, ten dated snapshots into 2.6, still agrees its version in an onboarding document.

CTV

CTV runs at 65 percent of commercial capacity. Part of that gap is demand that could not read the request.

Omdia's July 29 benchmark puts ad-supported CTV at 65 percent of commercial capacity and prescribes a bigger advertiser base. A seller's fill rate cannot tell a buyer who passed from a buyer who filtered the request before pricing it, and the CTV fields most likely to be wrong are the pod fields carrying the unsold slots.

Spec release

AdCOM 1.0-202607: new enums, five redefined playback methods, and two releases carrying the wrong field names

The July 16 AdCOM release adds the CTV Ad Portfolio enumerations, quietly rewords five existing playback methods, and ships a Content object whose field names were renamed by accident in March and reverted on main a week after the tag. What that does to anything generated from a tagged release.

Agentic

ARTF lets agents rewrite the bid request in flight. Nothing in it checks the result.

The Agentic RTB Framework specifies mutations against a live OpenRTB payload: eight intents, three operations, a path, and a typed payload. Every one of them can produce a request that is no longer valid for the version the exchange is running. What each intent touches, and where to put the check.

CTV

Live event ad insertion: a burst, not a stream, and the OpenRTB fields that carry it

A live break is thousands of impression opportunities released on one cue, with a hard deadline set by the transport stream. Which OpenRTB fields describe that, which one changed meaning in June 2026, and what a bid request for a live pod should actually look like.

Standards

Redefining Media Types: eight new claims, and the bidstream fields they land on

The IAB RMT Standard is in public comment until August 8, 2026 and is designed to be encoded directly into OpenRTB bid requests. Its eight impression-level attributes map onto fields that already exist and are already populated inconsistently. What to audit before the classification lands on top.

Revenue

Bid request quality is a revenue line: the auction economics of broken fields

Every malformed or missing field in a bid request removes bidders, and every removed bidder lowers the clearing price. How field-level breakage turns into CPM decay, QPS deprioritization, and unauditable revenue.

Protocol

What happens when your stack doesn't support an OpenRTB version? Nothing. That's the problem.

VAST has error 102 for version mismatches. OpenRTB has silence: unknown fields are ignored by design, and the version travels in an optional HTTP header. Where the signal actually drops, and how to catch it.

Privacy

What is bidstream data? Everything a bid request broadcasts, field by field

Regulators now use the word bidstream in enforcement orders. What it means at the protocol level: which OpenRTB fields carry location, identifiers, and context, who receives them, and what the spec can and cannot do about it.

Protocol

Will AI agents replace OpenRTB? Why the bid stream is the stable layer

Agentic advertising is reframing how media gets bought, but OpenRTB is not going away. Why both agent stacks build on the bid stream, what actually changes, and why validation matters more, not less.

Spec release

OpenRTB 2.6-202606, field by field: live content and discount macros

The June 2026 dated snapshot added content.realtime and content.firstbroadcast, redefined content.livestream, and added two discount macros. What changed and the migration it forces.

Agentic

AAMP, AdCP, and the bid stream: where agentic advertising actually touches OpenRTB

IAB Tech Lab's AAMP and AAO's AdCP both claim the agentic future. Where each one touches the bid stream, and the OpenRTB 2.6-202606 fields that shipped meanwhile.

CTV

CTV pod bidding grows up: duration floors, guaranteed deals, and live sports

The 2.6 pod bidding toolkit (podid, rqddurs, durfloors, mincpmpersec) was built for the live-sports CTV surge now underway. What sellers actually ship in 2026.

Spec release

OpenRTB 2.6-202505: what changed and what to do about it

A field-by-field look at the May 2025 OpenRTB update and the integration work it creates for exchanges and bidders, centered on the new data.cids field.

Signals

The User-Agent string is going away: sua, client hints, and what to send now

Chrome UA reduction froze device.ua years ago. How the structured device.sua object (UserAgent, BrandVersion) works, and why bidders should parse it first.

Privacy

DSA transparency in OpenRTB: where enforcement stands in 2026

The regs.ext.dsa and bid.ext.dsa extension two years into EU Digital Services Act enforcement: who requires it, what dsarequired values mean in practice.

Video

Three years of plcmt: the state of the placement migration

OpenRTB 2.6-202303 deprecated video.placement for plcmt in April 2023. Three years on, why dual-sending both fields is still the norm, not the exception.

Protocol

OpenRTB 3.0 and ads.cert in 2026: still waiting, still worth watching

Eight years after 3.0 went final, the layered protocol and its signed supply chain remain mostly unadopted. What would have to change, and what to do now.

Privacy

GPP in OpenRTB: regs.gpp, gpp_sid, and the 2026 state sections

Every GPP section id bid requests carry in 2026, what regs.gpp and regs.gpp_sid must contain per OpenRTB 2.6-202211, and the half-pair mistakes validators keep flagging.

Spec release

No more 2.7: how OpenRTB ships now, and why your parser should care

Since 2.6-202211, OpenRTB version numbers only move on breaking changes; everything else lands as dated snapshots. What that means for validation.

Spec release

OpenRTB 2.6-202501 in review: the January update, field by field

OpenRTB 2.6-202501 added content.gtax and content.genres for CTV genre signaling. What changed, who is affected, and how to check your fixtures against it.

IAB

What the IAB Tech Lab 2026 roadmap means for OpenRTB

IAB Tech Lab's 2026 roadmap is mostly agentic advertising. Its one OpenRTB post covers gtax, genres, and a Curation object excluded from OpenRTB itself.