Registries turn a brand into a legal entity with a number, dates, addresses, and named people. The thing nobody tells you first: registry structure varies enormously by jurisdiction, and that variance is the entire game. One country publishes full accounts, share registers, and directors' birth dates for free. Its neighbour publishes a name and a status code and charges for the rest. Your research strategy is not "look up the company" — it is "work out what this jurisdiction lets me see, then plan around the gap".

Second thing: search by company number, not name. The number is issued once and persists through renames, mergers, and dissolution. The name does not.

Registry-by-registry detail — what each exposes, its access model, and its identifier format: reference/registry-catalogue.md.

Filing types and how to read them: reference/filing-interpretation.md.

Beneficial ownership registers ask a company to declare the natural persons who ultimately own or control it above a threshold. The trajectory has broadly been registers opened to the public and then, in several jurisdictions, re-restricted to those who can show a legitimate interest, after legal challenge on privacy grounds. Assume access is conditional and check the current model before planning around it.

Four structural failure modes:

The correct output when you hit one of these is a documented terminus: "control traced to entity X in jurisdiction Y, whose register is not public; declared beneficial owner is Z, who also appears as declared owner of 40 unrelated entities and is assessed as a nominee." That is a finding.

Every jurisdiction requires a registered address, and a formation-agent industry exists to provide it. A single address hosting thousands of companies is completely normal. Before weighting it, identify what it is: a law firm or accountancy practice hosting clients is ordinary; a virtual-office provider is mildly interesting; a residential address with hundreds of companies is not ordinary. The useful signal is not the count but the overlap — which specific other entities at that address share officers, filing agents, or filing dates with yours. Same-day incorporations at the same address by the same agent is a batch, and batches are worth looking at.

Several jurisdictions publish essentially nothing: name and status, sometimes not even that, with officers and owners held only by the registered agent. For these, the ICIJ Offshore Leaks database is a legitimate and widely used research source. It aggregates entities, officers, intermediaries, and addresses from several journalistic investigations into offshore structures, and it is often the only public visibility into a closed register.

Use it correctly. It is a historical snapshot, not a live register, so absence means nothing and presence is as-of the leak. It records structures, not wrongdoing — offshore incorporation is lawful and ubiquitous. Names are as recorded in the leaked documents, with the transliteration inconsistencies that implies. Treat a hit as a lead requiring corroboration against a filing, a court record, or a contemporaneous document, and be careful how you characterise it in writing. OCCRP Aleph indexes leaks alongside registries and documents and is worth running the same names through.

The highest-value move available here. A person's directorship history across jurisdictions reveals prior ventures, dissolved companies, co-directors who recur, and business relationships that appear nowhere else.

Make it work: search the registry's normalised officer name form, not your preferred spelling. Try the surname alone in registries that allow it. Where the registry publishes a birth month and year, use it — it is the single best discriminator available for common names. Search former and married names. Account for transliteration: one person can appear under three romanisations of the same name across three registries, and no index links them.

Then verify. Two directorships under the same name are not one person. Confirm with a matching birth month/year, a matching service address, a matching co-director, or a corroborating source from . The officer pivot's false-positive rate on common names is the main way this technique produces confidently wrong network diagrams.

Dissolution removes an entity's legal personality; it does not usually remove its record. Most registries retain filings for years afterwards, and those filings are frequently the most informative in an investigation because they document a failure the principals would rather nobody found. Retention periods vary and some registries eventually purge, so archive dissolved-company filings when you find them. A director's trail of dissolved entities is one of the strongest single signals in corporate diligence.

Read the filing history chronologically before you read any individual document. The pattern carries information the documents do not:

Grade identity attribution separately from the record itself. A filing can be genuine and still not be your person.

Question: does the director of a UK supplier control other entities?

Most registry data is published for reuse, but conditions differ: several national registries impose licensing terms, attribution requirements, or rate limits, and several offer an official API or bulk product specifically so you do not scrape the web interface. Use them. Officer personal data is personal data — residential addresses and full dates of birth are protected in many registers, and deliberately circumventing a protected-address regime is an offence in some jurisdictions. Beneficial-ownership access may require you to assert a legitimate interest; assert one you actually have, in writing. Leak-derived datasets are lawful to research and are published by journalistic organisations for that purpose, but characterising a named person as wrongdoing on the basis of a leak entry alone is both an evidential and a defamation problem. Corroborate, and write carefully.