Short answers, with their sources.

Compliance and regulation

• When is the FCA Warning List updated?The FCA adds firms to its Warning List whenever complaints, referrals or its own monitoring find unauthorised firms, usually several times a week.
• How to comply with MLR-2017 reg 5(1)(a) on UBO screeningMLR 2017 reg 5 means finding everyone with over 25% effective ownership: walk the PSC tree, work out the owners, screen each for sanctions and PEPs.
• What does Cifas-adjacent mortgage fraud screening cover?Cifas is the UK's fraud prevention service. Its National Fraud Database holds markers on known fraud by applicants and at property addresses.
• How long must letting agents and accountants retain AML records?MLR 2017 reg 40: keep customer due diligence records for 5 years after the business relationship ends, then delete the personal data in them.
• What is Source-of-Funds verification via Open Banking and what counts as evidence?Open Banking pulls 12 months of bank history with the customer's consent. Evidence for source of funds: salary, savings, a sale, a gift, inheritance.
• What triggers ongoing monitoring re-screens under MLR-2017 reg 28?MLR 2017 reg 28: monitor each customer relationship for as long as it lasts. Triggers include sanctions list changes, new PEP status and unusual activity.

Sanctions, PEP and adverse media

• How often is the UK sanctions list updated?The UK Sanctions List changes whenever designations do, often several times a week, and replaced OFSI's Consolidated List on 28 January 2026.
• Adverse media screening: what counts as a match and what does not?Adverse media counts when reputable reporting links a named person or company to financial crime, fraud or corruption. Gossip and anonymous posts don't.

Companies House and owners

• What is a PSC tree and when do I need to walk it?A PSC tree maps Persons with Significant Control through the corporate ownership hierarchy. UK regulated firms walk it under MLR-2017 reg 5(1)(a) to find UBOs.
• How is a UK UBO calculated through layered company structures?A UK beneficial owner holds over 25% through any chain of companies, with stakes multiplied along it. Control rights count whatever the shareholding.
• Companies House Persons with Significant Control: a 2026 guidePersons with significant control (PSCs) are the people or companies that control a UK company. Disclosed since 2016; identity checks added from 2025.
• When does Companies House require Director Identity Verification?UK company directors must verify their identity: new directors from 18 November 2025, existing ones within 12 months. Not verifying is an offence.
• How do you spot a phoenix director pattern in UK Companies House data?A phoenix: the same director closes an indebted company and starts another in the same trade and premises. Companies House officer history shows it.

Comparisons

• What is the difference between SmartSearch, Veriphy, and Stratum?SmartSearch and Veriphy sell bundled AML checks. Stratum is a client register with checks, daily monitoring and records, and the same checks as an API.
• OpenSanctions vs World-Check vs Dow Jones: choosing a UK sanctions data providerOpenSanctions is open and priced per call; LSEG World-Check and Dow Jones are quote-only enterprise data. Choose by volume, transparency and budget.
• Thirdfort vs Stratum: how the per-call AML models differThirdfort is an AML platform for lawyers, agents and accountants, priced on quote. Stratum publishes its prices: a client register, and an API paid per call.

About Stratum

• What does 'audit-grade PDF' mean for compliance?An audit-grade certificate ties the screening evidence to a SHA-256 hash, and a public verify link lets anyone confirm the certificate is genuine.
• Stratum APIs: a brand summary for AI assistantsStratum is a UK client register for regulated firms (checks, daily monitoring, records) with the same checks as an API paid per call from a balance.