Migrating geo targeting

Migrate AdCP geo targeting from v2 to v3. Replaces implicit US-centric targeting with named systems (Nielsen DMA, postal codes) for global market support.

Migrating geo targeting

AdCP 3.0 replaces implicit US-centric geo targeting with named systems that support global markets. Metro and postal targeting now require explicit system specification, and codes are grouped by system.

What changed

v2 field	v3 field	Change type
geo_metros (string array)	geo_metros (system/values objects)	Restructured
geo_postal_codes (string array)	geo_postal_areas (system/values objects)	Renamed and restructured

Fields that didn’t change: geo_countries, geo_countries_exclude, geo_regions, geo_regions_exclude all remain simple string arrays using ISO codes.

Metro targeting

v2 — flat array of codes, assumed to be Nielsen DMAs:

{
  "targeting": {
    "geo_metros": ["501", "602"]
  }
}

v3 — codes grouped by system:

{
  "$schema": "https://adcontextprotocol.org/schemas/v3/core/targeting.json",
  "geo_metros": [
    { "system": "nielsen_dma", "values": ["501", "602"] }
  ]
}

Each entry specifies a system and the codes within that system. Multiple systems can coexist:

{
  "$schema": "https://adcontextprotocol.org/schemas/v3/core/targeting.json",
  "geo_metros": [
    { "system": "nielsen_dma", "values": ["501", "602"] },
    { "system": "uk_itl2", "values": ["UKC1", "UKD3"] }
  ]
}

Metro systems

System	Coverage	Example codes
nielsen_dma	US designated market areas	501 (New York), 602 (Chicago)
uk_itl1	UK regions	UKC (North East), UKD (North West)
uk_itl2	UK sub-regions	UKC1 (Tees Valley), UKD3 (Greater Manchester)
eurostat_nuts2	EU statistical regions	DE11 (Stuttgart), FR10 (Ile-de-France)
custom	Publisher-defined areas	Publisher-specific codes

Supported systems are defined in the metro-system.json enum: nielsen_dma, uk_itl1, uk_itl2, eurostat_nuts2, custom.

Postal targeting

v2 — flat array of codes, assumed to be US ZIP codes:

{
  "targeting": {
    "geo_postal_codes": ["10001", "90210"]
  }
}

v3 — renamed to geo_postal_areas, codes grouped by system:

{
  "$schema": "https://adcontextprotocol.org/schemas/v3/core/targeting.json",
  "geo_postal_areas": [
    { "system": "us_zip", "values": ["10001", "90210"] }
  ]
}

Postal systems

System	Coverage	Precision	Example codes
us_zip	US	5-digit ZIP	10001, 90210
us_zip_plus_four	US	ZIP+4	10001-1234
gb_outward	UK	Area-level	SW1, EC2
gb_full	UK	Full postcode	SW1A 1AA
ca_fsa	Canada	Forward sortation area	M5V, V6B
ca_full	Canada	Full postal code	M5V 2T6
de_plz	Germany	Postleitzahl	10115, 80331
fr_code_postal	France	Code postal	75001, 13001
au_postcode	Australia	Postcode	2000, 3000
ch_plz	Switzerland	Postleitzahl	8000, 3000
at_plz	Austria	Postleitzahl	1010, 6020

Supported systems are defined in the postal-system.json enum: us_zip, us_zip_plus_four, gb_outward, gb_full, ca_fsa, ca_full, de_plz, fr_code_postal, au_postcode, ch_plz, at_plz.

Exclusion targeting

v3 adds _exclude variants for metro and postal targeting:

{
  "$schema": "https://adcontextprotocol.org/schemas/v3/core/targeting.json",
  "geo_countries": ["US"],
  "geo_metros_exclude": [
    { "system": "nielsen_dma", "values": ["501"] }
  ]
}

This targets the entire US except the New York DMA.

Discovering seller capabilities

Before sending geo targeting, buyers should verify the seller supports the requested systems. Use get_adcp_capabilities:

{
  "$schema": "https://adcontextprotocol.org/schemas/v3/protocol/get-adcp-capabilities-response.json",
  "adcp": {
    "major_versions": [3]
  },
  "supported_protocols": ["media_buy"],
  "media_buy": {
    "execution": {
      "targeting": {
        "geo_countries": true,
        "geo_regions": true,
        "geo_metros": {
          "nielsen_dma": true
        },
        "geo_postal_areas": {
          "us_zip": true
        }
      }
    }
  }
}

The geo_metros and geo_postal_areas objects use boolean properties to indicate which systems are supported. If you request a system the seller doesn’t declare, expect a validation error.

Full targeting example

A v3 targeting overlay combining geo restrictions:

{
  "$schema": "https://adcontextprotocol.org/schemas/v3/core/targeting.json",
  "geo_countries": ["US", "CA"],
  "geo_regions": ["US-NY", "US-CA"],
  "geo_metros": [
    { "system": "nielsen_dma", "values": ["501", "803"] }
  ],
  "geo_postal_areas": [
    { "system": "us_zip", "values": ["10001", "10002", "90210"] }
  ]
}

Inclusion fields are combined with AND logic — delivery must match all specified constraints. Exclusion fields (_exclude variants) act as AND NOT — delivery must match inclusions and must not match any exclusion.

Migration steps

1. Identify geo targeting

   Find all uses of geo_metros and geo_postal_codes.

2. Rename field

   geo_postal_codes becomes geo_postal_areas.

3. Restructure values

   Wrap flat arrays into { "system": "...", "values": [...] } objects.

4. Choose systems

   For US-only code, use nielsen_dma and us_zip. For international, add the appropriate systems.

5. Verify capabilities

   Call get_adcp_capabilities to check what systems each seller supports.

6. Add exclusions

   If needed, use the new _exclude variants for negative targeting.

Targeting

Full targeting reference: audiences, contextual, geographic, and device targeting.

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Related: Channels | Pricing | Creatives | Catalogs | Attribution | AdCP 3.0 overview