Overview

The DPH registry (Dan z pridane hodnoty -- Value Added Tax) is the authoritative public register of VAT-registered entities in the Czech Republic, maintained and operated by the Czech Financial Administration (Financni sprava Ceske republiky) under the Ministry of Finance. The registry operates under the legal framework established by Act No. 235/2004 Coll., on Value Added Tax (Zakon o dani z pridane hodnoty), as amended, and provides real-time verification of VAT registration status for all taxable persons operating within the Czech tax jurisdiction.

The DPH registry serves a dual purpose in Czech business intelligence. First, it provides standard VAT number validation, confirming whether a given DIC (Danove identifikacni cislo -- Tax Identification Number, format CZxxxxxxxx) corresponds to a valid, active VAT registration. Second, and more critically for risk assessment purposes, it maintains the "Nespolehlivy platce DPH" (Unreliable VAT Payer) designation -- a publicly accessible flag indicating that a taxpayer has committed serious VAT compliance failures as defined in Section 106a of the VAT Act.

The unreliable payer designation carries significant legal consequences under Czech law. When a business transacts with an entity designated as an unreliable VAT payer, the business partner assumes joint and several liability (ruceni prijemce zdanitelneho plneni) for any unpaid VAT on that transaction under Section 109 of the VAT Act. This joint liability mechanism makes the DPH registry check not merely a best practice but a legal necessity for any entity conducting business with Czech counterparties. Failure to verify a supplier's DPH status before payment can result in the purchasing entity being held directly liable for the supplier's VAT obligations.

The Czech Financial Administration designates an entity as an unreliable VAT payer when it demonstrates patterns of serious VAT non-compliance, including systematic failure to file VAT returns, repeated failure to pay VAT obligations, or deliberate participation in VAT fraud schemes. Once designated, the flag remains public and is accessible to all business partners as a risk signal. The designation can be appealed and removed if the entity demonstrates sustained compliance improvement, but the historical fact of designation remains a significant risk indicator.

Data Sources and Coverage

The DPH registry provides several distinct data categories, each serving specific verification and compliance use cases.

Data Category	Description	Legal Basis
VAT Registration Status	Active, suspended, or cancelled registration	Section 94-95 VAT Act
DIC Number	Tax identification number (CZxxxxxxxx format)	Section 130 VAT Act
Unreliable Payer Flag	Designation as unreliable VAT payer	Section 106a VAT Act
Published Bank Accounts	Registered accounts for VAT payments	Section 96 VAT Act
Registration Date	Date of VAT registration and status changes	Administrative records
Group Registration	VAT group membership details	Section 95a-95b VAT Act
Effective Date	Date from which current status applies	Administrative records

Geographic and Temporal Scope

The DPH registry covers all VAT-registered entities operating in the Czech Republic, including Czech companies, foreign entities registered for Czech VAT, and VAT groups. The registry provides current-state data (not historical snapshots), meaning queries return the entity's status as of the moment of the query. For historical VAT status tracking, integration with the ARES historical data feed is required.

The registry also interfaces with the EU-wide VIES (VAT Information Exchange System) operated by the European Commission, enabling cross-border VAT number validation for all EU member states. Czech DIC numbers validated through VIES are confirmed against the DPH registry in real-time.

Czech Legal Context

The unreliable payer mechanism was introduced into Czech law on January 1, 2013, as part of anti-fraud measures targeting VAT carousel schemes. The mechanism creates a powerful economic incentive for business partners to verify VAT status: if a purchaser pays to a bank account that is not published in the DPH registry, or transacts with an unreliable payer without taking appropriate precautions, the purchaser becomes jointly liable for the unpaid VAT. This joint liability exposure can be substantial, particularly in high-value B2B transactions.

Legal Instrument	Relevance
Act No. 235/2004 Coll.	Primary VAT legislation establishing registration requirements
Section 106a	Unreliable payer designation criteria and procedures
Section 109	Joint liability for VAT when transacting with unreliable payers
Section 96	Published bank account requirements
Act No. 280/2009 Coll.	Tax Procedure Code governing administrative processes
EU VAT Directive 2006/112/EC	EU framework for VAT administration

Technical Architecture

The DPH registry is accessible through a public XML web service operated by the Czech Financial Administration at https://adisreg.mfcr.cz/adistc/. The service provides SOAP-based endpoints for individual DIC lookups and unreliable payer status checks.

Service Endpoints

Endpoint	Method	Description
`/adistc/DphReg`	SOAP/XML	VAT registration status lookup
`/adistc/NesijPlatci`	SOAP/XML	Unreliable payer status check
`/adistc/UctyDPH`	SOAP/XML	Published bank accounts lookup
VIES API	SOAP	EU-wide VAT validation via European Commission

Data Formats

The primary data format is XML over SOAP, with responses structured according to the Financial Administration's published schema. The VIES integration uses the European Commission's standard SOAP interface. No REST/JSON API is officially provided, though the Prismatic adapter normalizes all responses to JSON for platform integration.

API Integration

defmodule PrismaticOsint.Adapters.Dph do
  @moduledoc """
  Czech VAT Payer Registry (DPH) adapter for VAT verification,
  unreliable payer checks, and published bank account validation.
  Integrates with both the Czech Financial Administration SOAP
  service and the EU VIES system.
  """

  @behaviour PrismaticOsint.Adapter

  @doc """
  Comprehensive VAT status check for a Czech entity.
  Returns registration status, unreliable payer flag,
  and published bank accounts.
  """
  def check(dic) do
    with {:ok, status} <- check_registration(dic),
         {:ok, unreliable} <- check_unreliable(dic),
         {:ok, accounts} <- get_published_accounts(dic) do
      {:ok, %{
        dic: dic,
        registration: status,
        unreliable_payer: unreliable,
        published_accounts: accounts,
        joint_liability_risk: assess_liability_risk(unreliable),
        checked_at: DateTime.utc_now()
      }}
    end
  end

  @doc """
  Check VAT registration status.
  """
  def check_registration(dic) do
    case soap_call(:dph_reg, %{dic: normalize_dic(dic)}) do
      {:ok, response} ->
        {:ok, %{
          dic: dic,
          status: parse_status(response),
          registered_since: parse_date(response, :registration_date),
          vat_group: parse_group(response)
        }}

      {:error, reason} ->
        {:error, reason}
    end
  end

  @doc """
  Check if entity is designated as unreliable VAT payer.
  """
  def check_unreliable(dic) do
    case soap_call(:nesij_platci, %{dic: normalize_dic(dic)}) do
      {:ok, response} ->
        {:ok, %{
          dic: dic,
          is_unreliable: parse_unreliable_flag(response),
          designation_date: parse_date(response, :designation_date),
          reason: parse_reason(response)
        }}

      {:error, reason} ->
        {:error, reason}
    end
  end

  @doc """
  Get published bank accounts for VAT payments.
  """
  def get_published_accounts(dic) do
    case soap_call(:ucty_dph, %{dic: normalize_dic(dic)}) do
      {:ok, response} ->
        accounts = parse_accounts(response)
        {:ok, %{dic: dic, accounts: accounts, count: length(accounts)}}

      {:error, reason} ->
        {:error, reason}
    end
  end

  @doc """
  Validate VAT number through EU VIES system.
  """
  def vies_validate(vat_number) do
    {country_code, number} = split_vat_number(vat_number)
    case PrismaticOsint.Vies.check_vat(country_code, number) do
      {:ok, result} ->
        {:ok, %{
          vat_number: vat_number,
          valid: result.valid,
          name: result.name,
          address: result.address,
          country: country_code
        }}

      {:error, reason} ->
        {:error, reason}
    end
  end

  defp assess_liability_risk(%{is_unreliable: true}), do: :critical
  defp assess_liability_risk(_), do: :none
end

Bulk Compliance Screening Pipeline

defmodule PrismaticCompliance.Czech.VatScreener do
  @moduledoc """
  Bulk VAT compliance screening for Czech business partner portfolios.
  Checks registration status, unreliable payer flags, and bank account
  validity for all counterparties.
  """

  def screen_portfolio(entities) do
    results = entities
    |> Task.async_stream(fn entity ->
      with {:ok, dph} <- Dph.check(entity.dic),
           {:ok, ares} <- Ares.get_basic(entity.ico) do
        %{
          entity: entity,
          vat_status: dph.registration.status,
          unreliable: dph.unreliable_payer.is_unreliable,
          published_accounts: dph.published_accounts.accounts,
          liability_risk: dph.joint_liability_risk,
          company_name: ares.nazev
        }
      end
    end, max_concurrency: 5, timeout: 15_000)
    |> Enum.to_list()

    {:ok, %{
      screened: length(results),
      unreliable_payers: Enum.count(results, &match?({:ok, %{unreliable: true}}, &1)),
      high_risk: Enum.filter(results, &match?({:ok, %{liability_risk: :critical}}, &1)),
      screened_at: DateTime.utc_now()
    }}
  end
end

Use Cases

Mandatory Pre-Transaction Verification

Czech law effectively mandates DPH registry verification before any significant B2B transaction. Businesses must verify that their supplier is not designated as an unreliable VAT payer and must confirm that payments are directed to published bank accounts to avoid joint liability exposure. This verification should be performed at the point of invoice receipt, before payment authorization.

Supplier Portfolio Compliance Screening

Organizations with large supplier portfolios conduct periodic bulk screening of all active counterparties against the DPH registry. This screening identifies newly designated unreliable payers, expired VAT registrations, and changes in published bank accounts that could create compliance exposure. The screening frequency depends on risk appetite, but quarterly screening is considered minimum best practice.

M&A Due Diligence

During acquisition due diligence, the target company's complete supplier and customer portfolio is screened for DPH compliance risks. Active relationships with unreliable payers represent contingent liabilities that must be quantified and disclosed. Historical unreliable payer designations on the target company itself represent significant reputation and compliance risk.

Credit Risk Assessment

An entity's DPH status is a strong signal in credit risk models. Entities designated as unreliable VAT payers have demonstrated inability or unwillingness to meet tax obligations, which correlates strongly with broader financial distress. Combined with Insolvency Register data and Executors enforcement proceedings, DPH status provides a comprehensive credit risk profile.

Bank Account Verification for Payment Security

The published bank accounts feature of the DPH registry serves as an anti-fraud measure. Before processing payments, finance departments verify that the destination bank account appears in the DPH registry for the invoicing entity. Payments to non-published accounts can trigger joint liability under Section 109 and may also indicate invoice fraud or business email compromise.

Data Quality and Reliability

Quality Dimension	Assessment	Notes
Authority	Authoritative	Official government register; definitive legal status
Currency	Real-time	Status changes reflected immediately upon administrative decision
Accuracy	Very High	Direct from Czech Financial Administration databases
Completeness	Complete for registered entities	All Czech VAT-registered entities included
Historical Data	Current state only	No historical status tracking in DPH alone
Availability	High	Government service with good uptime; occasional maintenance windows

Limitations

The DPH registry provides current-state data only. To determine whether an entity was an unreliable payer at a specific historical date, integration with external monitoring or ARES historical feeds is required. The SOAP-based interface lacks modern API conventions (REST, JSON), requiring specialized adapter implementation. Published bank account data may not cover all accounts used by an entity, only those specifically registered for VAT purposes.

Platform Integration

Within the Prismatic Platform, the DPH registry is a core compliance verification source integrated into the Czech entity analysis pipeline. Every Czech company profile is automatically enriched with VAT status and unreliable payer flags during the standard entity resolution workflow.

The DPH adapter cross-references published bank accounts with payment records and triggers real-time alerts when a business partner's status changes to unreliable. Integration with ARES provides the entity resolution layer (mapping ICO to DIC), while integration with Hlidac statu provides additional analytics on entities with compliance concerns.

NABLA Compliance

NABLA Axiom	Compliance	Implementation
Signal Plurality	Compliant	DPH status cross-referenced with ARES, VIES, and Hlidac statu data
Contradiction Preservation	Compliant	Discrepancies between DPH and VIES status are flagged
Absence Informative	Compliant	Missing DPH registration for entity claiming VAT status flagged as anomaly
Time Decay	Compliant	All checks timestamped; stale status flags require re-verification
Unknown Valid	Compliant	SOAP service errors reported as unknown rather than assumed clear
Source Independence	Compliant	Direct government source independent of commercial data providers
Provenance Mandatory	Compliant	All results traced to specific SOAP response with timestamp

Performance Metrics

Metric	Value	Notes
Response Time	500ms-2s	SOAP service typical response time
Rate Limit	No official limit	Fair use expected; bulk queries should be throttled
Data Freshness	Real-time	Administrative decisions reflected immediately
Coverage	All CZ VAT entities	Complete coverage of registered taxpayers
VIES Integration	All 27 EU states	Cross-border validation available
Availability	~99%	Government service with scheduled maintenance
Data Format	XML/SOAP	Normalized to JSON by Prismatic adapter

ARES - Czech business registry that aggregates DPH data alongside company information
RZP - Trade Licensing Register for complementary entity verification
CNB - Czech National Bank regulated entities registry
Hlidac statu - Government watchdog with company analytics and risk scoring
Justice.cz - Commercial Register for company details and beneficial ownership
EU Sanctions - EU sanctions screening complementing VAT compliance checks
Insolvencni rejstrik - Insolvency data for entities with VAT compliance issues

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Created by Tomáš Korcak (korczis) | Open Source under GHL

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DPH

Capabilities

Try DPH

Overview

Data Sources and Coverage

Geographic and Temporal Scope

Czech Legal Context

Technical Architecture

Service Endpoints

Data Formats

API Integration

Bulk Compliance Screening Pipeline

Use Cases

Mandatory Pre-Transaction Verification

Supplier Portfolio Compliance Screening

M&A Due Diligence

Credit Risk Assessment

Bank Account Verification for Payment Security

Data Quality and Reliability

Limitations

Platform Integration

NABLA Compliance

Performance Metrics

Connect & Contribute

Intelligence Network

Related Content

Agent Ecosystem

Applications

Doctrine

DPH

Capabilities

Try DPH

Overview

Data Sources and Coverage

Geographic and Temporal Scope

Czech Legal Context

Technical Architecture

Service Endpoints

Data Formats

API Integration

Bulk Compliance Screening Pipeline

Use Cases

Mandatory Pre-Transaction Verification

Supplier Portfolio Compliance Screening

M&A Due Diligence

Credit Risk Assessment

Bank Account Verification for Payment Security

Data Quality and Reliability

Limitations

Platform Integration

NABLA Compliance

Performance Metrics

Related Resources

Connect & Contribute

Intelligence Network

Related Content

Agent Ecosystem

Applications

Doctrine