Seller-defined audiences (SDA) let publishers declare who their audience is in the bid request, without user identifiers. The Cookieless Audience database provides credible audience data at the domain level for 102 million domains, with every attribute aligned to IAB Audience Taxonomy 1.1 — so the crosswalk from data to declaration is direct.
The SDA framework, standardized by IAB Tech Lab, lets sellers attach audience meaning to inventory using shared taxonomies. With Safari, Firefox and iOS blocking cookies, 40%+ of traffic is cookieless — SDA works there natively.
Most publishers can only describe registered or subscribed users. The long tail of ad networks and multi-site sellers has no first-party evidence at all. Domain-level data provides a pre-computed audience profile for every property, in coded attributes the taxonomy already speaks.
Declarations carry taxonomy segment IDs, not user identifiers. Buyers interpret them consistently across sellers — and the seller never touches PII to produce them.
// OpenRTB bid request fragment — SDA declaration // segtax 4 = IAB Audience Taxonomy 1.1 "user": { "data": [{ "name": "yourdomain-sda", "ext": { "segtax": 4 }, "segment": [ { "id": "<node-id: Interest | Cycling>" }, { "id": "<node-id: Demographic | 35-44>" } ] }] } // Segment IDs come from your licensed copy of // Audience Taxonomy 1.1; declaration happens in // your own SSP, wrapper or ad server.
Our vocabularies were built aligned with IAB Audience Taxonomy 1.1, so each family of attributes has a natural home in the taxonomy’s three branches. The full field reference is on the taxonomy page.
8 age brackets, 5-point gender skew, 6 income bands, 7 education levels, 14 life stages, household composition, employment, home ownership and urbanicity crosswalk to the taxonomy’s demographic nodes.
INT.* → Interest branch29 interest groups and 285 sub-interests — INT.sports.cycling, INT.tech_computing.artificial_intelligence — map onto the taxonomy’s interest hierarchy node by node.
PI.* → Purchase Intent branch34 intent groups and 283 segments — PI.travel.hotels_and_resorts, PI.auto_ownership.new_vehicles — crosswalk to the purchase-intent branch, the commercially valuable end of an SDA declaration.
Five steps, with the declaration itself always happening in your own stack — the database supplies the mapping, your SSP or wrapper supplies the bid request.
Pull the database rows for your domains (or query the API) to get coded demographics, interests, intent and personas per property.
Keep attributes banded medium or high confidence — declare only what the evidence supports.
Map each retained attribute to its IAB Audience Taxonomy 1.1 node using the alignment built into the vocabularies.
Configure your SSP, wrapper or ad server to emit the segment IDs in OpenRTB user.data with ext.segtax: 4.
Publish the segment definitions and their evidence basis so DSP and agency buyers can evaluate — and pay for — the declaration.
A multi-site seller wants to declare a “cycling enthusiasts” audience across the cycling-adjacent portion of its network. The database rows for its domains supply the evidence; the crosswalk turns them into a declarable segment.
| Database attribute (code) | Reads as | Crosswalks to (Audience Taxonomy 1.1) |
|---|---|---|
INT.sports.cycling | Cycling interest | Interest › Sports › Cycling |
PI.sporting_goods.outdoor_recreation_equipment | Outdoor recreation equipment intent | Purchase Intent › Sporting Goods |
age_bracket = 35_44, gender_skew = male_lean | 35–44, male-leaning readership | Demographic › Age / Gender nodes |
income_level = upper_middle | Upper-middle income | Demographic › Income node |
confidence = high (interest), medium (intent) | Evidence strength per attribute | Governs what gets declared at all |
segtax: 4 on bid requests from its qualifying cycling domains, and publishes a one-page segment definition citing the underlying attributes and confidence bands. Buyers see a standardized, taxonomy-coded audience on inventory that never had cookies to begin with. The exact node IDs come from the seller’s licensed copy of Audience Taxonomy 1.1 — the placeholders above mark where they slot in.| Registered first-party data | Contextual signals only | Domain-level audience data (this dataset) | |
|---|---|---|---|
| Coverage of your traffic | Logged-in share only — often single digits | All pages, but describes content, not audience | Every domain in the corpus, audience-described |
| Taxonomy fit | Needs manual mapping to Audience Taxonomy 1.1 | Maps to Content Taxonomy, not Audience | Vocabularies aligned with Audience Taxonomy 1.1 by design |
| Long-tail / network sellers | Rarely available | Available but audience-blind | 102M-domain coverage, head to tail |
| Privacy posture | Consent-dependent PII | No PII | No PII anywhere in the pipeline |
| Best use | Premium logged-in segments | Adjacency and suitability | Audience declarations at property scale — and the three combine well |
SDA is an IAB Tech Lab framework that lets sellers declare audience segments on their own inventory inside OpenRTB bid requests, using standardized taxonomy segment IDs instead of user identifiers. The segtax extension identifies which taxonomy the IDs come from — 4 designates IAB Audience Taxonomy 1.1 — so any buyer can interpret the declaration the same way, from any seller.
Because it removes the translation step. Our demographic fields, INT.* interests and PI.* purchase-intent segments were built aligned with Audience Taxonomy 1.1, so each attribute has a corresponding taxonomy branch and node. Instead of inventing a mapping from proprietary segments to the taxonomy, you crosswalk directly — and the fixed v1.0 vocabularies mean the crosswalk stays stable across quarterly refreshes.
No. The database describes domains and the real-time API describes pages, for planning, analysis and segment construction. Your SSP, wrapper or ad server emits the actual SDA declaration at request time from the mapping you configured. We deliberately do not claim impression-level pre-bid classification — the value here is credible, taxonomy-aligned evidence for what you declare.
Yes. Start with domain-level records for property-wide segments, then use the real-time API to profile representative URLs per section — the sports vertical of a general news site can declare different segments than its finance vertical. Both layers use the same vocabularies, so section-level and domain-level declarations stay consistent.
Package the same audience meaning behind Deal IDs.
The buy-side view of the same domain-level audience data.
Turn declared segments into sales-ready audience stories.
Find the advertisers your declared audiences are worth to.
Look up your properties in the audience demo, or license the domain file and build your first taxonomy-aligned SDA segments this quarter.
Open the audience demo See database pricing