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PUT /api/v2/buyer/advertisers/{advertiserId}/test-cohorts/{cohortId} Updates an existing test cohort. All body fields are optional — send only what you want to change; omitted fields keep their current values.

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Request

curl -X PUT https://api.interchange.io/api/v2/buyer/advertisers/12345/test-cohorts/cohort_abc123 \
  -H "Authorization: Bearer $SCOPE3_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "West Coast Treatment Group - Updated",
    "definition": {
      "type": "geo_region",
      "regions": ["US-CA", "US-OR", "US-WA", "US-NV"]
    },
    "estimatedSize": 62000
  }'

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Parameters

FieldTypeRequiredNotes
advertiserIdstringYesPath parameter — the owning advertiser
cohortIdstringYesPath parameter — the cohort ID
namestringNoCohort label (max 255)
descriptionstringNoFree-text description (max 1000)
cohortTypestringNoFree-form classification
roleenumNoTREATMENT, CONTROL, OBSERVATION
definitionobjectNoTargeting definition. type is required; additional fields vary by type
estimatedSizeintegerNoSize estimate for power analysis

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Response

{
  "id": "cohort_abc123",
  "advertiserId": "12345",
  "name": "West Coast Treatment Group - Updated",
  "description": null,
  "cohortType": "geographic",
  "role": "TREATMENT",
  "definition": { "type": "geo_region", "regions": ["US-CA", "US-OR", "US-WA", "US-NV"] },
  "estimatedSize": 62000,
  "isActive": true,
  "createdAt": "2026-01-15T10:30:00Z",
  "updatedAt": "2026-03-20T14:45:00Z"
}
Returns the full cohort after the update.

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Errors

  • 400 VALIDATION_ERROR — invalid role or a definition missing its type.
  • 404 NOT_FOUND — cohortId (or advertiserId) does not exist or is not visible to the authenticated customer.
See Errors for the full error contract.

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Get test cohort

Read the current cohort