According to the Basel Committee's Customer Due Diligence for Banks paper, one of the essential elements of a sound KYC programme is customer identification. This includes obtaining sufficient information to understand the nature and purpose of the customer relationship, the source of funds, and the beneficial ownership and control structure of the customer1. For corporate business entities, this means that a bank needs to have an understanding of the structure of the company, such as its legal form, its ownership, its directors, its line of business, and its geographical locations2. This will help the bank to assess the risk profile of the customer, to verify its identity and legitimacy, and to monitor its transactions for any suspicious activities.
References:
1: Customer due diligence for banks, Basel Committee on Banking Supervision, October 2001, Section III.2 2:
General Guide to Account Opening and Customer Identification, Basel Committee on Banking Supervision, February 2003, Section 2.2.1 Reference: https://www.bis.org/publ/bcbs77.pdf

Explanation/Reference: https://ico.org.uk/for-organisations/guide-to-freedom-of-information/receiving-a-request/

The potential client is attempting to commit the illegal activity of using insider information to trade securities.
Insider information is any material, non-public information that could affect the price or value of a security, such as earnings reports, mergers, acquisitions, or regulatory actions. Insider trading is the act of buying or selling securities based on insider information, which gives the trader an unfair advantage over other investors who do not have access to such information. Insider trading violates the principles of market integrity, fairness, and transparency, and can undermine investor confidence and trust. Insider trading is also a form of market abuse and financial crime, and is subject to civil and criminal penalties.
References:
ACAMS Study Guide for the CAMS Certification Examination - 6th Edition, Chapter 1: Risks and Methods of Money Laundering and Terrorism Financing, Section 1.3: Financial Crime, Subsection
1.3.3: Market Abuse, pp. 25-26
ACAMS CAMS Certification Video Training Course, Module 1: Risks and Methods of Money Laundering and Terrorism Financing, Lesson 1.3: Financial Crime, Sublesson 1.3.3: Market Abuse, Video Time: 2:00-3:30 Exam CAMS: Certified Anti-Money Laundering Specialist (the 6th edition), Question 12, Answer C

The USA PATRIOT Act is a comprehensive legislation that was enacted in 2001 to enhance the powers and tools of the US authorities to combat money laundering, terrorist financing, and other threats to the national security and the integrity of the financial system. The USA PATRIOT Act contains several provisions that affect the relationship between US banks and foreign banks that maintain correspondent accounts in the US.
One of these provisions is Section 319, which allows the US authorities to seize the funds of a foreign bank held with a US bank, if the foreign bank refuses to comply with a subpoena or a request for records related to the correspondent account. This provision is intended to prevent foreign banks from using their correspondent accounts in the US to facilitate transactions involving tainted funds, such as proceeds of crime, funds intended to support terrorism, or funds subject to sanctions or asset freezing orders. Section 319 also requires US banks to maintain records of the owners and agents of foreign banks that have correspondent accounts with them, and to terminate such accounts if requested by the US authorities.
Therefore, if a foreign bank maintains a correspondent account in the US, and the US authorities find out that the account has been used to facilitate a transaction involving tainted funds, the US authorities can seize the funds of the foreign bank held with the US bank, under the authority of the USA PATRIOT Act.
References:
CAMS Study Guide - 6th Edition, Chapter 1, Section 1.2, page 10
USA PATRIOT Act, Section 319, page 55-57
The USA PATRIOT Act: A Legal Analysis, Section III, page 9-10
[The USA PATRI
Reference:
https://www.fincen.gov/fact-sheet-section-312-usa-patriot-act-final-regulation-and-notice-proposed-rulemaking