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London

Founded in 2012, Signature Litigation has grown into one of London’s pre-eminent specialist dispute resolution practices. From the outset, we set out to do things differently: a conflict-free, disputes-only platform designed to give clients the undivided focus and strategic agility that complex, high-stakes matters demand.

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Gibraltar

Established in 2017, Signature Litigation's Gibraltar office was founded to address growing demand for specialist expertise in commercial litigation and private wealth disputes on the Rock.

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Paris

Signature Litigation AARPI houses one of France’s most enviable product liability practices, with the team also handling commercial and corporate litigation, insurance and reinsurance, toxic tort and ESG, civil fraud and asset tracing, international arbitration, administrative and public law.

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Frankfurt

Frankfurt has emerged as one of Europe's foremost financial and commercial centres and, increasingly, as a bridge between European and Asian markets. With that growth comes an increasing demand for sophisticated dispute resolution. Signature Litigation established its Frankfurt office to meet this need, bringing our conflict-free, disputes-only platform to the German market.

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Duncan Grieve

Partner

In his own words:
In his own words:

Duncan brings exceptional intellect and a ‘go above and beyond’ attitude while managing multijurisdictional cases.

– Chambers UK 2027

Duncan Grieve is a go-to for complex, multijurisdictional investigations. He does the full gambit of financial crime across sectors. I think he’s a very astute tactician.

– Chambers UK 2027

Duncan brings a wealth of experience to large, complex investigations and has an exceptional talent for problem‑solving.

– Chambers UK 2027

Duncan’s knowledge of the law is excellent and he is always very commercial. He is very personable and hard-working and goes the extra miles for clients.

– Chambers UK 2027

Duncan Grieve is an outstanding professional with deep technical knowledge and extensive experience.

– Chambers UK 2027

Duncan is brilliant with clients and brings a wealth of experience to bear complex cases with difficult tactical and strategic issues. I would unhesitatingly recommend him.

– Chambers UK 2027

Duncan has unparalleled experience in managing enforcement actions by multiple regulators and a phenomenal track record of achieving strong outcomes for clients. He is an expert on Latin American matters and is a very astute tactician.

– Chambers UK 2027

Duncan Grieve is an outstanding professional with deep technical knowledge and extensive experience in matters involving Brazil. He combines a strong understanding of Brazilian legal, regulatory, and cultural nuances with a pragmatic and commercially focused approach, which consistently adds value to complex cross-border matters.

– Chambers UK 2027

Duncan is a Partner at our London office specialising in investigations and white collar crime.

He is regularly instructed to represent companies, boards and individuals on cross-border investigations involving issues in foreign jurisdictions and has advised on many of the major multinational cases of the last 15 years.

He has market-leading experience in Brazil, Portugal and Lusophone Africa and has also handled major matters involving Russia, China, India, South Africa, Ecuador, Kazakhstan, Saudi Arabia, Germany, Greece, Romania, the Czech Republic, Canada and Japan.

A fluent Portuguese speaker, Duncan spent two years in Brazil advising clients in investigations stemming from Lava Jato (Operation Car Wash), including the negotiation of novel leniency agreements with Brazilian prosecuting authorities and regulatory agencies. His combination of fifteen years cross-border investigations experience, on-the-ground experience in Brazil and fluency in Portuguese is unique in the London market.

Duncan represents individual clients subject to internal, regulatory and criminal investigation. He advises on all sensitivities and risks arising from such matters including legal, reputational and privacy issues and is attuned to the need to maintain relationships with government and regulatory authorities. He has acted for numerous clients in relation to public enquiries and Parliamentary Select Committee appearances.

Duncan also advises on financial sanctions and trade embargoes. He provides counsel to clients on the application of UK sanctions across a range of sectors and assists clients to comply with reporting obligations to the UK authorities, as well as handling investigations into potential sanctions breaches.

He provides expert support to General Counsel, Chief Compliance Officers and boards in relation to broader compliance issues. He leads major integrity initiatives, for example, conducting a global compliance integration for a multinational manufacturing conglomerate following a USD 5.1 billion acquisition. He regularly handles pre-acquisition anti-corruption due diligence in relation to investments into foreign jurisdictions.

Duncan advises clients on issues relating to broader governance and risk issues including non-financial misconduct, environmental breaches and in other areas where the regulatory landscape is rapidly evolving.

Duncan is ranked in the Chambers UK 2027 Guide for both Financial Crime: Individuals and Corporate Crime & Investigations, recognising his experience in handling international investigations and regulatory proceedings for both corporates and individuals. Duncan is described as “a go-to for complex, multi-jurisdictional investigations”, with a commentator noting that he is “an expert on Latin American matters and is a very astute tactician.” He is also commended for his “‘go above and beyond’ attitude to managing multi-jurisdictional cases” and “exceptional talent for problem‑solving.”

Duncan is recommended in The Legal 500 UK 2027 Guide for Regulatory Investigations and Corporate Crime. In The Legal 500, he is praised for being an “extremely clever lawyer, focused and strategic with excellent commercial acumen.” He is known in the market for having “unparalleled experience in managing simultaneous enforcement actions by multiple international regulators and achieving successful outcomes for his clients.” In previous Guides, he is further described as an “astute tactician”, and “a star.” He was listed in Global Investigations Review’s “40 under 40” in 2024.

He regularly delivers presentations on bribery, corruption, governance and effective compliance strategies, and lectures and publishes on these topics in the UK and Brazil. He co-authors the Brazil chapter of the American Bar Association International Guide to Corporate Internal Investigations.

Prior to joining Signature, Duncan was a Partner in the White Collar Defense and Investigations team at Cadwalader, Wickersham & Taft in London.

Governmental / Regulatory Corporate Investigations

  • Led global investigation linked to the Luanda Leaks Investigation. Representing multinational consulting client in interactions with UK, U.S., Portuguese and Angolan authorities. Resulted in favourable declination in August 2024.
  • 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.
  • Representing 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).
  • Representing concessionaire in investigation initiated by a multilateral development bank into a significant Brazilian infrastructure project.
  • Advising a leading technology company on a multi-faceted investigation involving criminal proceedings in the Czech Republic.

Internal Investigations

  • Internal investigation for multinational client in the pharmaceutical sector responding to multiple whistleblowing allegations involving Germany, Kazakhstan and Saudi Arabia.
  • Multiple 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 a multinational technology company into embezzlement and corruption in Romania and Austria.

Monitorships

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

Sanctions / Export Controls

  • Advising multinational financial institutions, fund managers and lenders on sanctions compliance and the exclusion of designated persons/ entities from fund structures.
  • Advising and assisting clients with the application of UK Russian sanctions to transactions in the oil and gas sector.
  • Representing a natural resources company on potential sanctions breaches in the shipping sector.
  • Advising a multi-billion dollar asset management firm on the application of UK Russian sanctions to individual investors.

Anti-Bribery and Corruption Due Diligence

  • During a nine-month, full-time client secondment, led the global compliance integration of newly acquired company purchased for US USD 5.1 billion by a NASDAQ-listed conglomerate.
  • Advising on anti-corruption risks relating to an investment into a Brazilian multinational’s mining operation in Mozambique.
  • Anti-corruption due diligence on a USD 500 million international investment into the Brazilian mining sector.

Individual Representations

  • Representing a senior executive in SFO and DOJ investigation into alleged bribery in the Ecuadorian state insurance market. The investigation was dropped against client pre-charge.
  • Representing a senior executive in SFO and DOJ investigations and civil claims relating to the “Tuna Bonds” case involving multi-billion dollar infrastructure investments in Mozambique.
  • Representing individuals under potential criminal investigation by HMRC. The criminal tax investigation was dropped.
  • Representing 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.
  • Representing General Counsel in numerous investigations including into high-profile accounting irregularities at a major retailer.
  • Representing 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.
  • Preparing senior executives for appearances before UK Parliamentary Select Committees.
  • Representing 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.
  • Representing clients in relation to the negotiation of individual leniency agreements with the Brazilian Ministério Público Federal (MPF).

Article: Crypto that could be criminal – New Law Journal – 22 October 2026

Article: Record of £4.7 million Russian sanctions penalty signals new OFSI enforcement landscape – Thomson Reuters Regulatory Intelligence – 15 October 2026

Article: OFSI’s largest Russian sanctions penalty: Takeaways and practical tips – Global Relay Intelligence & Practice – 6 October 2026

Article: UK’s new cryptoasset regulations: FCA significantly expands remit, enforcement powers – Thomson Reuters Regulatory Intelligence – 15 September 2026

Article: Crypto meets criminal law: The UK’s new regulatory regime – Global Relay Intelligence & Practice – 11 September 2026

Article: FCA signals tougher approach to individual fines in enforcement shake-up – Financial Reporter – 16 July 2026

Article: Bigger fines, bigger risks: what UK FCA’s penalty reforms mean for individuals – Thomson Reuters Regulatory Intelligence (CUBE) – 10 July 2026

Article: FCA moves to reform policy on penalties for individuals – Global Relay Intelligence & Practice – 2 July 2026

Article: SFO Plan Focuses On Resilience But Funding Doubts Persist – Law360 – 6 May 2026

Article: Legal advice privilege and intra-client documents: widening the scope – Thomson Reuters PLC Magazine – 30 April 2026

Article: Organised crime risk and capital markets: what the Banco Master fallout means for foreign investors – Thomson Reuters Regulatory Intelligence – 12 March 2026

Article: Odebrecht in Peru: why the latest criminal charges matter for every arbitration user – Financial Regulation International – November 2025

Article: What the SFO’s new Corporate Compliance guidance means in practice –Thomson Reuters Regulatory Intelligence – 19 December 2025

Article: Collateral consequences: corruption’s ripple effect on arbitration – Litigation Finance Insider – 7 December 2025

Article: Lingering shadows: when corruption scandals generate a second wave of arbitration claims – Thomson Reuters Regulatory Intelligence – 27 November 2025

Press Quote: U.K. enforcement appetite over off-channel comms grows as U.S. wanes – Compliance Week – 1 October 2025

Article: Criminal charges in Peru matter for everyone – The Law Society Gazette – 26 September 2025

Press Quote: HSBC Using AI To Fight Fraud Under ‘Failure To Prevent’ Law – Law360 – 24 September 2025

Article: What UK’s New Prosecution Guidance Means For Compliance – Law360 – 18 September 2025

Article: Failure to prevent fraud: key takeaways for directors – Business & Accountancy Daily – 15 September 2025

Article: ANALYSIS: SFO-CPS issue corporate prosecution guidance – Thomson Reuters Regulatory Intelligence – 2 September 2025

Press Quote: Prosecutors Warn Companies Ahead Of UK Fraud Offense – Law360 – 26 August 2025

Press Quote: Financial services firms dealt tens of millions in regulatory fines – City AM – 17 July 2025

Press Quote: Signature Launches White Collar Crime and Investigations Practice with New Partner Team Hire – Corporate Counsel Business Journal – 14 July 2025

Press Quote: Mark Beardsworth and Duncan Grieve join Signature Litigation – Litigation Finance Insider – 14 July 2025

Press Quote: Revolving Doors: Linklaters adds eight-lawyer Paris team as Goodwin hires in London and Broadfield recruits from Sidley and Kirkland – Legal Business – 11 July 2025

Press Quote: The Revolving Door: Goodwin Nabs Debt Pro From Kirkland – Law360 – 11 July 2025

Press Quote: Dynamic Duo Putting a Signature on White Collar Crime – Edward Fennell’s Legal Diary – 11 July 2025

Press Quote: Signature makes twin London partner hire to launch white-collar crime practice – The Global Legal Post – 11 July 2025

Press Quote: Signature Hires 2 Pros For New White-Collar Crime Practice – Law360 – 10 July 2025

Press Quote: Signature launches new practice with white-collar duo – CDR News – 10 July 2025

Press Quote: Goodwin and Cadwalader Partners Leave to Launch Signature’s White Collar Practice – Law.com International – 10 July 2025