Duncan Grieve 

Partner – London
T.+44 (0) 20 7170 8579
100 Bishopsgate
London EC2N 4AG
United Kingdom V-CARD

Duncan Grieve is a partner in Cadwalader’s White Collar Defense and Investigations Practice, resident in the London office.

Duncan advises a range of organizations, including multinationals, both on internal corporate investigations and during investigation or prosecution by regulatory bodies including the Serious Fraud Office (SFO), the Financial Conduct Authority (FCA), the Office of Financial Sanctions Implementation (OFSI), the U.S. Department of Justice (DOJ) and the U.S. Securities and Exchange Commission (SEC). He has deep experience in dealing with international investigations involving issues in foreign jurisdictions, including Brazil, Portugal and Lusophone Africa as well as Russia, China, India, Romania, the Czech Republic, Canada and Japan.

Duncan advises clients on financial sanctions and trade embargoes. He provides counsel on the application of UK sanctions to corporate / fund structures and transactions in various sectors. He also assists clients to comply with reporting obligations to the UK sanctions authorities and handles investigations into possible sanctions breaches.

Duncan also represents individuals subject to internal, regulatory and criminal investigation. He has acted for clients in relation to Parliamentary Select Committee appearances.

In addition to contentious work, Duncan has extensive experience in anti-corruption compliance in an M&A context. During a secondment to a multinational client, he led the global compliance integration of newly acquired company which was purchased for US$5.1 billion. He regularly conducts pre-acquisition anti-corruption due diligence in relation to investments into foreign jurisdictions.

Duncan is a member of Cadwalader’s Environmental, Social, and Governance (ESG) taskforce and advises clients on compliance with rapidly-evolving regulatory obligations and investigations relating to these areas.

Duncan speaks fluent Portuguese and spent two years in Brazil working with a Brazilian law firm where he advised corporate and individual clients in investigations stemming from Lava Jato (Operation Car Wash), including the negotiation of leniency agreements with Brazilian prosecuting authorities and regulatory agencies (MPF, CADE, CGU, TCU).

Duncan was named to GIR’s “40 under 40” global list of next generation investigations specialists in 2024 and in Who’s Who Legal – Future Leaders 2020-2024. He was also listed as a Global Leader in 2021 and 2022 as ”A great name for Brazil-related investigations" and "…outstanding on criminal defence and investigations matters”. He was listed in GIR 100 2020, a guide to the world’s leading cross-border investigations practices. He is also listed as a “Key Lawyer” in the 2021 and 2022 Legal 500 UK in the areas of Regulatory Investigations and Corporate Crime (Advice to Corporates) and White Collar Crime (Advice to Individuals) “representing individual clients in multijurisdictional investigations, with a particular niche in cases involving Latin American jurisdictions”.

He regularly delivers presentations on bribery, corruption, ESG and effective compliance strategies, and has lectured and published on these topics in the UK and Brazil.

Duncan is admitted to practice in England and Wales.

Representative Matters

Sanctions / Export Controls

  • Advised a multinational financial institution on the exclusion of designated persons/ entities from fund structures.
  • Assisted clients with the application of UK Russian sanctions to transactions in the oil and gas sector.
  • Represented a natural resources company on potential sanctions breaches in the shipping sector.
  • Advised a multi-billion dollar asset management firm on the application of UK Russian sanctions to individual investors.

Governmental / Regulatory Investigations

  • Global investigation linked to the Luanda Leaks ICIJ Investigation. Representing multinational client in interactions with UK, U.S., Portuguese and Angolan authorities.
  • First external lawyer on the ground at the commencement of a major, multijurisdictional investigation into the pharmaceutical sector. Successful negotiation of corporate resolution and dialogue with investigating authorities in the UK, U.S., Switzerland and Greece.
  • Represented numerous infrastructure-sector clients in investigations stemming from Lavo Jato including the negotiation of novel corporate leniency agreements with Brazilian prosecuting authorities and regulatory agencies (MPF, CADE, CGU, TCU).
  • Represented concessionaire in investigation initiated by a multilateral development bank into a significant Brazilian infrastructure project.
  • Advised a leading technology company on a multi-faceted investigation involving criminal proceedings in the Czech Republic.

Internal Investigations

  • Numerous internal investigations worldwide. Numerous representations relating to infrastructure projects in Brazil, South America and Africa including interviews, site visits and remedial actions.
  • Workplace misconduct investigation for multinational, automotive-sector client involving the UK, Switzerland and Romania.
  • Investigation and subsequent demerger of a technology joint venture located in Tatarstan, Russia.
  • Investigation for multinational technology company into embezzlement and corruption in Romania.


  • Acted for DOJ-appointed independent monitor of a Brazil-headquartered international conglomerate operating in engineering, infrastructure and petrochemicals sectors.

Individual Representations

  • Regular representation of individual clients in proceedings and interviews with the UK Financial Conduct Authority, the UK Serious Fraud Office, the London Metals Exchange, the U.S. Department of Justice, SEC, CFTC and FBI.
  • Acted for general counsel in numerous investigations including into high-profile accounting irregularities at a major retailer.
  • Acted for numerous senior executives and traders during the investigation and subsequent criminal proceedings relating to LIBOR, EURIBOR, the FX market, the gold/ silver fix and the aluminium market.
  • Prepared senior executives for appearances before UK Parliamentary Select Committees.
  • Acted for a senior executive during the investigation and criminal proceedings relating to phone hacking at the News of the World newspaper.
  • Advising on a private criminal prosecution brought against a Lebanese financial institution.
  • Acted for clients in relation to the negotiation of individual leniency agreements with the Brazilian Ministério Público Federal (MPF).

Anti-Bribery and Corruption Due Diligence

  • Led the global compliance integration of newly acquired company purchased for US$5.1 billion by a NASDAQ-listed conglomerate.
  • Advised on anti-corruption risks relating to an investment into a Brazilian multinational’s mining operation in Mozambique.
  • Anti-corruption due diligence on a $500m international investment into the Brazilian mining sector.


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Duncan Grieve 


  • England & Wales


  • University of York
  • BPP Law School, Manchester
  • BPP Law School, Manchester