Subjectum Company Registry KYB API

API ID 13807

Real-time company registry lookup and KYB verification for Czech Republic (ARES) and Slovakia (RPO) — normalized company data with automated risk flags (newly founded, liquidation, bankruptcy status).

API Documentation

Endpoints

Request
Simple health check endpoint to verify that the Subjectum API service is running and reachable. Returns HTTP 200 with basic service status. Useful for uptime monitoring before making authenticated lookup requests.
Endpoint ID: 31658
GET https://zylalabs.com/api/13807/subjectum+company+registry++kyb+api/31658/healthz
INPUT PARAMETERS

Free test requests remaining: 3 of 3.

This endpoint does not require any input parameters.

API EXAMPLE RESPONSE
JSON
{
    "status": "ok",
    "service": "Subjectum — Company Registry & KYB Verification API"
}
Healthz — CODE SNIPPETS

curl --location --request GET 'https://zylalabs.com/api/13807/subjectum+company+registry++kyb+api/31658/healthz' --header 'Authorization: Bearer YOUR_API_KEY' 


    
Request
Looks up a company by registration number (IČO) in the official Czech (ARES) or Slovak (RPO) business registry and returns normalized company data, statutory representatives, and automated KYB risk flags (newly founded, liquidation, bankruptcy status).
Endpoint ID: 31660
GET https://zylalabs.com/api/13807/subjectum+company+registry++kyb+api/31660/lookup-company
INPUT PARAMETERS

lookup-company — Endpoint Features

Object Description
ico Required Company registration number (IČO), e.g. 27074358
country Optional Country registry to query: CZ or SK. If omitted, the API attempts to guess it from the IČO format.

Free test requests remaining: 3 of 3.


INPUT PARAMETERS

ico
country
API EXAMPLE RESPONSE
JSON
{
    "query": {
        "ico": "27074358",
        "country_hint": "CZ"
    },
    "company": {
        "name": "Asseco Central Europe, a.s.",
        "ico": "27074358",
        "dic": "CZ27074358",
        "ic_dph": "CZ27074358",
        "legal_form": "Akciová spoločnosť",
        "address": {
            "street": "Budějovická 778",
            "city": "Praha",
            "zip": "14000",
            "country": "Česká republika"
        },
        "founded_date": "2003-08-06",
        "status": "ACTIVE",
        "statutory_representatives": []
    },
    "risk_flags": {
        "newly_founded": false,
        "recent_address_change": false,
        "recent_representative_change": false,
        "insolvency_related": false,
        "risk_score": 0
    },
    "metadata": {
        "data_source": "ARES",
        "source_last_updated": "2026-09-03",
        "confidence_score": 1,
        "country": "CZ"
    }
}
Lookup-company — CODE SNIPPETS

curl --location --request GET 'https://zylalabs.com/api/13807/subjectum+company+registry++kyb+api/31660/lookup-company?ico=27074358&country=CZ' --header 'Authorization: Bearer YOUR_API_KEY' 


    

API Access Key & Authentication

After signing up, every developer is assigned a personal API access key, a unique combination of letters and digits provided to access to our API endpoint. To authenticate with the Subjectum Company Registry KYB API simply include your bearer token in the Authorization header.

Headers
Header Description
Authorization Required Should be Bearer access_key. See "Your API Access Key" above when you are subscribed.

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Overview

Subjectum is a headless REST API for Know Your Business (KYB) verification and company registry lookups across Central Europe.

Send a company registration number (IČO) and receive normalized, structured data pulled directly from official government registries — no manual searching, no scraping, no inconsistent formats across countries.

Currently supported:
- Czech Republic — via ARES (Administrativní registr ekonomických subjektů), the official Czech business registry
- Slovakia — via RPO (Register právnických osôb), the official Slovak business registry

Every response includes:
- Normalized company data: legal name, registration number, tax ID (DIČ/IČ DPH), legal form, registered address, founding date, and current legal status
- Statutory representatives where available from the source registry
- Automated risk flags: newly founded company (under 6 months), liquidation status, bankruptcy status, and confidence scoring
- Explicit data source attribution and last-updated timestamp for every lookup, so you always know exactly where the data came from and how fresh it is

Use cases: automated KYB/AML onboarding checks, vendor and supplier due diligence, B2B fraud prevention, CRM enrichment, and compliance workflows that need verified company data instead of self-reported information.

Support for Poland and Hungary is planned for a future release via commercial data partners. Requests for those countries currently return a clear, machine-readable "not yet supported" response rather than failing silently.

Built on FastAPI with strict schema validation — every response is guaranteed to match the documented structure.

Subjectum Company Registry KYB API FAQs

The API returns normalized company data, including legal name, registration number, tax ID, legal form, registered address, founding date, and current legal status. It also provides statutory representatives and automated risk flags indicating newly founded status, liquidation, and bankruptcy.

Key fields in the response include "name," "ico," "dic," "legal_form," "address," "founded_date," "status," and "risk_flags." Each field provides essential information about the company and its legal standing.

The response is structured in a JSON format with distinct sections: "query" for input parameters, "company" for company details, "risk_flags" for risk assessments, and "metadata" for data source and confidence scoring. This organization facilitates easy parsing and utilization.

The data is sourced directly from official government registries: ARES for the Czech Republic and RPO for Slovakia. This ensures that the information is accurate and up-to-date, reflecting the latest legal statuses.

Data accuracy is maintained through direct integration with official registries, ensuring real-time updates. Each response includes a "source_last_updated" timestamp, allowing users to verify the freshness of the data.

Typical use cases include automated KYB/AML onboarding checks, vendor and supplier due diligence, B2B fraud prevention, and CRM enrichment. The API provides verified company data essential for compliance workflows.

Users can customize requests by specifying the company registration number (IČO) and optionally providing a "country_hint" to indicate the desired registry. This allows for targeted lookups in the Czech Republic or Slovakia.

If a lookup returns no results, the API will provide a clear response indicating that the company was not found. Users should implement checks for empty results to handle such scenarios gracefully in their applications.

General FAQs

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