> ## Documentation Index > Fetch the complete documentation index at: https://docs.particle.pro/llms.txt > Use this file to discover all available pages before exploring further. # List publishers for a sponsor > Returns the podcast publishers a sponsor advertises across, ordered by podcast coverage (the count of distinct publisher podcasts where the sponsor appears). Surfaces the bundle-buy signature: a sponsor showing 60–100% coverage on multiple publishers is doing network buys, not per-show buys. ## OpenAPI ````yaml /openapi.json get /v1/podcasts/advertising/sponsors/{id}/publishers openapi: 3.1.0 info: description: Public API for Particle — news intelligence, financial data, and analysis. title: Particle API version: 0.1.0 servers: - url: https://api.particle.pro security: - ApiKeyHeader: [] - BearerAuth: [] paths: /v1/podcasts/advertising/sponsors/{id}/publishers: get: tags: - Podcast Advertising - tier:premium summary: List publishers for a sponsor description: >- Returns the podcast publishers a sponsor advertises across, ordered by podcast coverage (the count of distinct publisher podcasts where the sponsor appears). Surfaces the bundle-buy signature: a sponsor showing 60–100% coverage on multiple publishers is doing network buys, not per-show buys. operationId: list-sponsor-publishers parameters: - description: Results per page explode: false in: query name: limit schema: default: 25 description: Results per page format: int64 maximum: 100 minimum: 1 type: integer - description: Opaque pagination cursor from previous response explode: false in: query name: cursor schema: description: Opaque pagination cursor from previous response type: string - description: >- Sponsor ID, company ID, company domain, or company slug. When the value resolves to a company (not a specific sponsor), the response aggregates across every sponsor linked to that company — the canonical 'where does this advertiser buy?' view. When it resolves to a sponsor ID, the response is scoped to that single deduped sponsor. in: path name: id required: true schema: description: >- Sponsor ID, company ID, company domain, or company slug. When the value resolves to a company (not a specific sponsor), the response aggregates across every sponsor linked to that company — the canonical 'where does this advertiser buy?' view. When it resolves to a sponsor ID, the response is scoped to that single deduped sponsor. type: string responses: '200': content: application/json: schema: $ref: '#/components/schemas/PageSponsorPublisherEntry' description: OK default: content: application/problem+json: schema: $ref: '#/components/schemas/PlatformError' description: Error x-codeSamples: - label: cURL lang: curl source: |- curl -H "X-API-Key: $PARTICLE_API_KEY" \ "https://api.particle.pro/v1/podcasts/advertising/sponsors/{id}/publishers?limit=25" components: schemas: PageSponsorPublisherEntry: additionalProperties: false properties: cursor: description: Pass to next request for more results type: string data: description: List of results items: $ref: '#/components/schemas/SponsorPublisherEntry' type: - array - 'null' has_more: description: Whether more results exist type: boolean required: - data - has_more type: object PlatformError: additionalProperties: false properties: detail: description: >- A human-readable explanation specific to this occurrence of the problem. examples: - Property foo is required but is missing. type: string error_code: type: string errors: description: Optional list of individual error details items: $ref: '#/components/schemas/ErrorDetail' type: - array - 'null' instance: description: >- A URI reference that identifies the specific occurrence of the problem. examples: - https://example.com/error-log/abc123 format: uri type: string resolve: $ref: '#/components/schemas/ErrorResolve' status: description: HTTP status code examples: - 400 format: int64 type: integer title: description: >- A short, human-readable summary of the problem type. This value should not change between occurrences of the error. examples: - Bad Request type: string type: default: about:blank description: A URI reference to human-readable documentation for the error. examples: - https://example.com/errors/example format: uri type: string type: object SponsorPublisherEntry: additionalProperties: false properties: ad_count: description: Ads from this sponsor on the publisher's catalog format: int64 type: integer coverage_share: description: >- podcast_coverage / publisher.total_podcasts (0..1). A sponsor with coverage_share >= 0.25 on a publisher is doing a network buy across the catalog. format: double type: number episode_reach: description: Distinct episodes featuring the sponsor on the publisher's catalog format: int64 type: integer first_seen_at: description: Earliest detected ad appearance format: date-time type: string last_seen_at: description: Most recent ad appearance format: date-time type: string podcast_coverage: description: Distinct podcasts in the publisher where the sponsor appears format: int64 type: integer publisher: $ref: '#/components/schemas/PodcastPublisherCompact' description: Publisher reference publisher_podcast_count: description: Total podcasts in the publisher's catalog format: int64 type: integer required: - publisher - publisher_podcast_count - ad_count - podcast_coverage - coverage_share - episode_reach type: object ErrorDetail: additionalProperties: false properties: location: description: >- Where the error occurred, e.g. 'body.items[3].tags' or 'path.thing-id' type: string message: description: Error message text type: string value: description: The value at the given location type: object ErrorResolve: additionalProperties: false properties: action: type: string endpoint: type: string message: type: string method: type: string url: type: string required: - message type: object PodcastPublisherCompact: additionalProperties: false properties: id: description: Publisher ID type: string name: description: Publisher name type: string slug: description: >- Human-readable slug identifier (e.g., 'goalhanger', 'iheartpodcasts'). When present, accepted in place of the ID anywhere a publisher reference is taken in the API. Occasionally absent on publishers whose name doesn't slugify (e.g., scripts not representable in ASCII URL slugs). type: string required: - id - name type: object securitySchemes: ApiKeyHeader: description: Pass your API key in the X-API-Key header (recommended). in: header name: X-API-Key type: apiKey BearerAuth: description: Pass your API key as a Bearer token in the Authorization header. scheme: bearer type: http ````