Client Due Diligence API for Accounting and Law Firms

Accounting firms, bookkeepers, gestorías and asesorías in Spain, expert-comptables in France, law firms, company-formation agents and trust or company service providers are obliged entities under the UK Money Laundering Regulations 2017, Spain's Ley 10/2010, France's Code monétaire et financier, and — from 10 July 2027 — the EU Anti-Money-Laundering Regulation. Most of these firms have no developer on staff and no budget for a platform built for banks. Prometiam gives them two ways to run the same client check: a REST API for firms with a developer, and a Model Context Protocol (MCP) server for firms without one.

Two ways in

With a developer: GET /companies/search resolves a client by NIF, SIREN/SIRET, company_number or name; GET /companies/{id} returns status, address, capital and officers, with include=risk_flags for Spain's AEAT large-debtor flag and include=insolvency for an insolvency block; GET /people/search covers officers and UK Persons with Significant Control; GET /sanctions/screen is beta, with PEP screening beta and Spain-only; GET /search covers Spanish concursal notices and POST /insolvency/check covers corporate insolvency in nine other markets; GET /vat/{vatNumber} validates a VAT number against VIES; POST /monitor keeps a Spanish, Irish or Polish client under ongoing watch. Without a developer: run npx -y prometiam-risk-mcp in Claude Desktop or Cursor with the same API key, and ask for the check in plain language instead of writing one.

Honest limits

Prometiam verifies the company and its filed officers — it does not check a person's identity document. Beneficial ownership is exposed only for the UK, through the PSC register; every other country returns officers and directors, which is not the same thing. Ireland and Poland are company-level with no officer data yet, and Norway has no corporate-event stream. Insolvency notices are corporate only. Sanctions screening is beta; PEP screening is beta, Spain-only, and never includes relatives or close associates. None of this is legal advice — it produces a dated record for the file, not a compliance determination.

A firm with a few hundred business clients, checked at onboarding and re-checked yearly with monthly screening, typically fits the free tier or Starter; a few thousand clients fits Professional. Read the full pattern · Get a free API key

Frequently asked questions

Do I need a developer to run these checks?
No. The MCP server runs in Claude Desktop or Cursor with the same API key a developer would use — a partner just asks for the check in plain language. REST is the other option if you have a developer.
Does this verify the identity of the people behind the company?
No. Prometiam verifies the company and its filed officers; it does not check a photo ID or confirm who you are actually dealing with.
Does it cover beneficial ownership, not just directors?
Only for the UK, through Persons with Significant Control. Every other registry returns officers and directors, which is not the same thing as beneficial ownership.
What does a client due diligence check actually record?
A timestamped registry answer, the current officers where held, a sanctions result with its match score and threshold, and an insolvency answer. Not a legal opinion or a compliance certificate.
What will this cost a small firm?
A firm with a few hundred clients, checked at onboarding and re-checked yearly with monthly screening, typically stays inside the free tier or Starter (€9.99/month). A few thousand clients usually fits Professional (€29.99/month).