openapi: 3.2.0
info:
  title: ATF eRegulations Notices API
  version: '2026-09-05'
  summary: Read-only JSON API over ATF's eRegulations platform (27 CFR Parts 447, 478, 479, 555, 646, 771).
  description: Machine-readable description of the public JSON API served at https://regulations.atf.gov/api/.
  contact:
    name: Bureau of Alcohol, Tobacco, Firearms and Explosives
    url: https://www.atf.gov/contact
  license:
    name: U.S. Government Work (17 U.S.C. 105)
    url: https://www.usa.gov/government-works
servers:
- url: https://regulations.atf.gov/api
  description: ATF eRegulations production API (anonymous, no key)
tags:
- name: Notices
  description: Federal Register notices that amend the ATF parts.
paths:
  /notice:
    get:
      operationId: listNotices
      tags:
      - Notices
      summary: List Federal Register notices affecting the ATF parts
      parameters:
      - name: part
        in: query
        required: false
        description: Restrict to notices touching one CFR part (e.g. 478).
        schema:
          type: string
          examples:
          - '478'
      responses:
        '200':
          description: Notice list
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/NoticeList'
  /notice/{documentNumber}:
    get:
      operationId: getNotice
      tags:
      - Notices
      summary: Retrieve one Federal Register notice with its amendment instructions
      parameters:
      - name: documentNumber
        in: path
        required: true
        description: Federal Register document number, e.g. 2026-01141.
        schema:
          type: string
          examples:
          - 2026-01141
      responses:
        '200':
          description: Notice detail
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Notice'
components:
  schemas:
    Amendment:
      type: object
      properties:
        instruction:
          type: string
          description: The verbatim Federal Register amendment instruction.
        cfr_part:
          type: string
        authority:
          type: string
    Notice:
      type: object
      required:
      - document_number
      - cfr_parts
      - fr_url
      properties:
        document_number:
          type: string
        title:
          type: string
        cfr_title:
          type: integer
        cfr_parts:
          type: array
          items:
            type: string
        fr_citation:
          type: string
        fr_volume:
          type: integer
        fr_url:
          type: string
          format: uri
        publication_date:
          type: string
          format: date
        effective_on:
          type: string
          format: date
        comments_close:
          type: string
          format: date
        primary_agency:
          type: string
        primary_docket:
          type: string
        dockets:
          type: array
          items:
            type: string
        regulation_id_numbers:
          type: array
          items:
            type: string
        versions:
          type: object
          additionalProperties: true
        amendments:
          type: array
          items:
            $ref: '#/components/schemas/Amendment'
        section_by_section:
          type: array
          items:
            type: object
            additionalProperties: true
        supporting_documents:
          type: array
          items:
            type: object
            additionalProperties: true
        footnotes:
          type: object
          additionalProperties: true
        meta:
          type: object
          additionalProperties: true
    NoticeSummary:
      type: object
      required:
      - document_number
      - fr_url
      - publication_date
      properties:
        document_number:
          type: string
          examples:
          - 2019-06266
        effective_on:
          type: string
          format: date
        publication_date:
          type: string
          format: date
        fr_url:
          type: string
          format: uri
          description: Canonical federalregister.gov URL for the notice.
    NoticeList:
      type: object
      required:
      - results
      properties:
        results:
          type: array
          items:
            $ref: '#/components/schemas/NoticeSummary'
x-generated-from: live probe of https://regulations.atf.gov/api/* on 2026-09-05
x-api-evangelist-modeled: true
x-upstream-project: https://github.com/atfweb/regulations-core