Audience Targeting in DOOH: The IAB Taxonomy, Segtax=600, and the Real Segments Buyers Actually Bid On

DOOH audience targeting used to mean "fitness centers in Houston" or "bars in Brooklyn between 6pm and 9pm." Geographic + venue. That was the whole stack.

The Trillboards audience layer is structurally different. Every impression carries the IAB Audience Taxonomy 1.1 segment array (segtax=4) alongside the Trillboards segtax=600 namespace for CV-unique signals. DSPs can target with two-namespace precision, "Pets owners at pet stores in California during weekend mornings" is a single OpenRTB predicate expressed across five fields. The demand-side benefit is cleaner attribution; the supply-side benefit is 20-40% premium clearing CPMs on inventory carrying the full signal payload.

This page is the consolidated reference for the audience targeting surface. The taxonomy package is open source (@trillboards/iab-taxonomy). The OpenRTB encoding is the standard user.data array with segtax markers. The per-segment observation data is published daily at /data/audiences/iab/ and /data/audiences/attributes/.

Live network data

The audience signal layer as of the latest snapshot:

• 26,269 active screens emitting the IAB Audience Taxonomy segment array
• 34 countries covered by the signal pipeline
• 60 venue categories with characteristic audience signatures
• IAB AT 1.1 dictionary: 230+ leaf segments, observation counts published daily

The two-namespace targeting stack

IAB Audience Taxonomy 1.1 (segtax=4)

The industry-standard segment library. Trillboards ships every leaf node that has been observed on the network in the last 30 days as a dedicated page at /data/audiences/iab/. Each leaf page shows:

• The full taxonomy path (root → branch → leaf)
• 30-day observation count across the Trillboards network
• Top 3-5 venue categories where the segment fires most often
• Top US cities for the segment
• Cross-references to the buyer-side documentation

High-volume segments observed across the network:

• Pets (IAB 690) , cross-references the pet-store venue category, veterinary clinics, and grooming services
• Auto Intender (IAB 688) , cross-references auto-repair shops, oil change shops, gas stations, and tire shops
• Sports Fans (IAB 686) , cross-references bars, restaurants, sports bars, and bowling alleys
• Foodies (IAB 692) , cross-references coffee shops, restaurants, and bakeries
• Tech Early Adopters (IAB 685) , cross-references coffee shops, coworking spaces, and airport lounges
• Health & Wellness (IAB 691) , cross-references fitness centers, gyms, and yoga studios
• Travel Enthusiasts (IAB 693) , cross-references airport lounges and hotel lobbies
• Beauty & Personal Care (IAB 694) , cross-references hair salons, barbershops, and nail salons

The complete IAB AT 1.1 leaf catalog with observation counts and venue co-occurrences is at /data/audiences/iab/.

Trillboards Segtax=600 Namespace

The Trillboards-specific namespace covers CV-unique signals that have no IAB equivalent. Every signal is constrained to a small enum to keep the bid-request payload size bounded and DSP-side decoding predictable:

audience_group_composition, describes the social structure in front of the screen at observation time. Enum values:

• solo , individual viewer
• pair , two viewers, often couple or friend-pair
• small_group , three to five viewers, often friend-group or family
• mixed_group , larger heterogeneous gathering
• family_unit , detected family pattern (parents + children)
• coworkers , business-attire group

audience_intent_stage, describes the inferred purchase journey position. Enum values:

• awareness , passive browsing
• consideration , comparison shopping
• decision , active purchase mode
• post_purchase , follow-up engagement
• unknown , signal not extractable

audience_attire_archetype, describes the dominant attire pattern. Enum values:

• business , business-formal or business-casual
• casual , everyday casual wear
• athleisure , athletic-leisure crossover
• formal , evening / event formalwear
• uniform , workplace uniforms
• streetwear , urban streetwear
• outdoor , outdoor / activewear

audience_activity_macro, describes the dominant activity context. Enum values:

• commuting , transit + commuter venues
• dining , food + beverage venues
• shopping , retail venues
• leisure , entertainment + recreation
• waiting , service queues (auto, medical, salon)
• working , coworking + office contexts
• transit , airport / station / hub

The full Trillboards attribute catalog with per-attribute, per-value observation counts is at /data/audiences/attributes/.

How the signals get into the bid request

The on-device CV pipeline runs continuously while the screen is active. It observes faces, attention vectors, group structures, and attire patterns, runs them through the Trillboards classification stack, and produces segment labels from the record it keeps for each person it detects.

When the device fires its periodic OpenRTB 2.6 bid request to the Trillboards SSP, the signals ride the standard user.data array:

user: {
  data: [
    {
      id: "iab-at-1.1",
      ext: { segtax: 4 },
      segment: [
        { id: "690", value: "Pets" },
        { id: "692", value: "Foodies" }
      ]
    },
    {
      id: "trillboards-600",
      ext: { segtax: 600 },
      segment: [
        { id: "audience_group_composition:family_unit" },
        { id: "audience_intent_stage:decision" },
        { id: "audience_activity_macro:shopping" }
      ]
    }
  ]
}

DSPs reading the bid request use the segtax extension to disambiguate. A DSP that understands only IAB AT 1.1 reads the segtax=4 entry and ignores the segtax=600 entry. A DSP that understands both reads them both. Backward compatibility is guaranteed by the OpenRTB extension mechanism, older DSPs see standard fields, newer DSPs see the full matrix.

What sits under the segments

Every segment is read from per-person records. The screen keeps one for each person its camera detects: estimated age range, gender, dominant emotion, dwell time and the time spent looking at the screen.

• On screens running the full sensing profile the screen also computes a face-identity template, a vector of 512 numbers that Trillboards uses to recognise the same person across screens and days. Trillboards links each person to the device keys of the phones seen with them and to mobile advertising IDs.
• Selected camera frames go to a cloud model that estimates ethnicity, age band, gender, social composition, purchase-intent stage, activity, attire, carried items, lifestyle segments and mood. Trillboards keeps those frames for 400 days.
• The bid request carries the segments with the screen's IP address, its location and its live audience measurements.
• Trillboards sells and shares audience measurement and location data with its data partners, including 375ai and Intuizi.

The /data/* pages publish the counts: every segment and attribute value with its 30-day observation count.

Audience targeting across the venue topology

The audience-segment × venue-category cross-correlation is the heart of the targeting surface. The patterns are stable across the network:

At coffee shops: Foodies (IAB 692) fires on 78% of impressions; Tech Early Adopters (IAB 685) fires on 31%; audience_attire_archetype=casual fires on 64%; audience_activity_macro=working fires on 42%.

At bars and sports bars: Sports Fans (IAB 686) fires on 56% of impressions; Foodies (IAB 692) fires on 38%; audience_group_composition=small_group fires on 47%; audience_activity_macro=leisure fires on 71%.

At fitness centers and gyms: Health & Wellness (IAB 691) fires on 89% of impressions; Sports Fans (IAB 686) fires on 43%; audience_attire_archetype=athleisure fires on 83%.

At pet stores and veterinary clinics: Pets (IAB 690) fires on 91% of impressions; audience_group_composition= family_unit fires on 38%; audience_intent_stage=decision fires on 47%.

At auto-repair shops and oil change shops: Auto Intender (IAB 688) fires on 73% of impressions; audience_activity_macro= waiting fires on 81%; audience_intent_stage=consideration fires on 52%.

At hair salons and barbershops: Beauty & Personal Care (IAB 694) fires on 84% of impressions; audience_activity_macro= waiting fires on 78%.

At airport lounges and hotel lobbies: Travel Enthusiasts (IAB 693) fires on 67% of impressions; Tech Early Adopters (IAB 685) fires on 41%; audience_attire_archetype=business fires on 54%.

Geographic concentration of audience signals

Audience segments cluster geographically. Pets (IAB 690) over-indexes in California, Texas, Florida, and the Pacific Northwest. Tech Early Adopters (IAB 685) over-indexes in Bay Area cities, Boston, Seattle, Austin, and New York. Sports Fans (IAB 686) over-indexes in markets with active major-league teams.

The full geographic × segment cross-correlation is computed daily and published via the per-segment pages at /data/audiences/iab/, each of which lists its top 5-10 US cities by observation count. The per-state DOOH market data is at /data/locations/ with one page per US state and one page per top-500 US city.

Frequently asked questions

The FAQ block above covers the buyer-side and operator-side questions most relevant to audience targeting. For the underlying programmatic mechanics (OpenRTB protocol, waterfall, settlement), see the Programmatic DOOH hub page. For the venue-side perspective on what signals each venue category naturally emits, see the venue catalog.

Related Trillboards data surfaces

• IAB segment dictionary , 230+ IAB AT 1.1 leaf segments observed across the network
• Trillboards attributes , segtax=600 attire / intent / activity / group composition
• Venue catalog, every venue with characteristic audience signature
• Location atlas, state and city DOOH market data
• Demand ecosystem, DSP
  • SSP support for the audience taxonomy
• Audience signals workflow , how signals flow from device to DSP
• Brand-safety categories , IAB content category controls (orthogonal to audience targeting)
• State of DOOH 2026: Audience Archetypes , the annual research chapter on audience patterns