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Katten Muchin Rosenman UK LLP

Work 020 7776 7620
Fax 020 7776 7621

John Ahern

Work +44 (0) 20 7770 5253
Katten Muchin Rosenman LLP

Work Department

Financial Services


John Ahern, partner at Katten Muchin Rosenman UK LLP and head of the London Financial Services group, focuses his practice on banking and financial services regulation with a strong focus on the UK and European financial markets and related regulations. His background in private practice and as in-house counsel at a global investment bank provides him with a perspective on the unique regulatory issues facing the wholesale and private banking sectors. John advises multilateral trading facilities, broker-dealers and banks on trading, clearing and settlement as well as client money and custody of securities—both physical and dematerialized. He has a particular focus on regulatory capital, and advises a number of banks and other authorized firms on the requirements and implications of the prudential regime. John counsels asset managers and investment advisors on the regulation of alternative funds in Europe.

John assists clients in navigating the regulatory system and counsels them in documenting a range of customer relationships, including the preparation of client agreements, inter-group arrangements, trading platform rulebooks and related compliance documentation.

John is a frequent speaker at seminars and conferences and has written a number of articles for well-respected publications on financial services regulations.

London: Corporate and commercial

Financial services

Within: Financial services

'A leading firm in the area of derivatives financial regulation', Katten Muchin Rosenman UK LLP is 'able to provide a bridge between UK/EU law as it applies to firms in the US and to explain the UK/EU rules in a manner that the US entities understand'. Dual US and UK-qualified 'industry veteranNathaniel Lalone has an excellent reputation among clearing firms and 'is able to compare the two regimes (US and EU/UK) and explain the differences in a way that is clear, concise and simple, yet also factually correct and legally sound'. The 'extremely responsive, practical and commercialNeil Robson has a strong reputation among buy-side entities, including hedge and private equity fund managers, on the ongoing regulatory issues affecting their businesses including as it relates to AIFMD and MiFID ii. David Brennand and US-qualified  Carolyn Jackson are also recommended and the firm also hired John Ahern  in early 2018 to head its London financial services group. Ahern focuses his practice on banking and financial services regulation

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