CEF Radar

CEF Radar Investors API

The large investors who file notices about owning 5% or more of a fund, and those notices.

Documentation GitHub OpenAPI

Operations 5

GET /api/v1/campaigns Where the large investors hold stakes: one row per investor-and-fund, with the… #

GET /api/v1/activists The large investors we follow, with how many funds each is in now #

GET /api/v1/activists/{slug} One large investor: its funds, its recent notices, what it usually does #

GET /api/v1/filings The newest notices large investors filed about owning 5% or more of a fund, one… #

GET /api/v1/filings/{accession} One notice by its document number: who filed it, about which fund, the stake… #

Specifications

⚙

OpenAPI

https://artifacts.apis.io/cefradar-com/openapi/cefradar-com-investors-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: CEF Radar Investors API
  description: 'Everything CEF Radar says about a U.S. closed-end fund - who is targeting it, what it is asking holders to do and by when, what it costs, how much it borrows and what it holds - as plain JSON, read from public filings at the U.S. Securities and Exchange Commission. Every fact carries `as_of` and `source_url`; every answer carries a `notice` and a `Link: rel="terms-of-service"` header. Information, not advice. 100 requests a day per address without a key; `Authorization: Bearer ` raises the budget to the plan''s. Assistants have their own server (Model Context Protocol) at https://cefradar.com/mcp; a plain-text guide is at https://cefradar.com/llms.txt.'
  termsOfService: https://cefradar.com/terms#api
  contact:
    name: CEF Radar
    url: https://cefradar.com/for-developers
  license:
    name: CC BY 4.0 (the compiled data; text all rights reserved)
    url: https://creativecommons.org/licenses/by/4.0/
  version: 0.1.0
servers:
- url: https://cefradar.com
tags:
- name: Investors
  description: The large investors who file notices about owning 5% or more of a fund, and those notices.
paths:
  /api/v1/campaigns:
    get:
      tags:
      - Investors
      summary: 'Where the large investors hold stakes: one row per investor-and-fund, with the…'
      operationId: list_campaigns
      parameters:
      - name: status
        in: query
        required: false
        schema:
          type: string
          description: active | exited | all
          default: active
          title: Status
        description: active | exited | all
      - name: cef
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: 1 = closed-end funds only, 0 = non-CEF, omit = all
          title: Cef
        description: 1 = closed-end funds only, 0 = non-CEF, omit = all
      - name: activist
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: activist slug
          title: Activist
        description: activist slug
      - name: issuer
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: issuer ticker or slug
          title: Issuer
        description: issuer ticker or slug
      - name: page
        in: query
        required: false
        schema:
          type: integer
          minimum: 1
          default: 1
          title: Page
      - name: per_page
        in: query
        required: false
        schema:
          type: integer
          maximum: 200
          minimum: 1
          default: 50
          title: Per Page
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
                title: Response List Campaigns
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
  /api/v1/activists:
    get:
      tags:
      - Investors
      summary: The large investors we follow, with how many funds each is in now
      operationId: list_activists
      parameters:
      - name: page
        in: query
        required: false
        schema:
          type: integer
          minimum: 1
          default: 1
          title: Page
      - name: per_page
        in: query
        required: false
        schema:
          type: integer
          maximum: 200
          minimum: 1
          default: 100
          title: Per Page
      - name: cef_focus
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Cef Focus
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
                title: Response List Activists
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
  /api/v1/activists/{slug}:
    get:
      tags:
      - Investors
      summary: 'One large investor: its funds, its recent notices, what it usually does'
      operationId: get_activist
      parameters:
      - name: slug
        in: path
        required: true
        schema:
          type: string
          title: Slug
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
                title: Response Get Activist
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
  /api/v1/filings:
    get:
      tags:
      - Investors
      summary: The newest notices large investors filed about owning 5% or more of a fund, one…
      operationId: list_filings
      parameters:
      - name: since
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: YYYY-MM-DD (filed_at >= since)
          title: Since
        description: YYYY-MM-DD (filed_at >= since)
      - name: until
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: YYYY-MM-DD (filed_at <= until)
          title: Until
        description: YYYY-MM-DD (filed_at <= until)
      - name: form
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: SC 13D | SC 13D/A | SC 13G | SC 13G/A
          title: Form
        description: SC 13D | SC 13D/A | SC 13G | SC 13G/A
      - name: cef
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: 1 = closed-end fund subjects only
          title: Cef
        description: 1 = closed-end fund subjects only
      - name: activist
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: activist slug
          title: Activist
        description: activist slug
      - name: issuer
        in: query
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          description: issuer ticker
          title: Issuer
        description: issuer ticker
      - name: page
        in: query
        required: false
        schema:
          type: integer
          minimum: 1
          default: 1
          title: Page
      - name: per_page
        in: query
        required: false
        schema:
          type: integer
          maximum: 200
          minimum: 1
          default: 50
          title: Per Page
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
                title: Response List Filings
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
  /api/v1/filings/{accession}:
    get:
      tags:
      - Investors
      summary: 'One notice by its document number: who filed it, about which fund, the stake…'
      operationId: get_filing
      parameters:
      - name: accession
        in: path
        required: true
        schema:
          type: string
          title: Accession
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
                title: Response Get Filing
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
components:
  schemas:
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          type: array
          title: Detail
      type: object
      title: HTTPValidationError
    ValidationError:
      properties:
        loc:
          items:
            anyOf:
            - type: string
            - type: integer
          type: array
          title: Location
        msg:
          type: string
          title: Message
        type:
          type: string
          title: Error Type
        input:
          title: Input
        ctx:
          type: object
          title: Context
      type: object
      required:
      - loc
      - msg
      - type
      title: ValidationError