Exclusively active in international disputes, Three Crowns LLP‘s London office acts for corporations in heavyweight investor-state proceedings brought against states, including matters that are not treaty-based. The team also defends states against claims. The practice is co-led by the ’extremely sharp and convincing’ Constantine Partasides KC, who regularly obtains multibillion-dollar awards and is increasingly involved in arbitration-related litigation; and Gaëtan Verhoosel, who has a strong track record in complex investment treaty cases. The team further showcases Middle Eastern disputes specialist Reza Mohtashami KC, who acts for oil supermajors, construction firms, sovereign states and state entities; Manish Aggarwal, an expert in investor-state arbitrations under both UNCITRAL and ICSID rules; and Leilah Bruton, who ‘has amazing attention to detail’. Other names to note are energy disputes practitioner Hamid AbdulkareemFarouk El-Hosseny, a specialist in commercial and investor-state disputes in the telecoms and oil and gas sectors; and Ridhi Kabra, who acts in investment treaty arbitrations in relation to taxation, infrastructure, telecoms, joint ventures, and oil and gas disputes. Carmen Martinez Lopez relocated to the firm’s Madrid office in October 2023.

Legal 500 Editorial commentary

Testimonials

Collated independently by Legal 500 research team.

  • ‘3C Law Firm has outstanding expertise in both commercial and investment arbitration - money well spent.’

  • ‘Three Crowns LLP's team composition and expertise are perfect for clients’ needs. The quality of work and submissions are excellent, and the integrity and style of the individuals is unprecedented and superb.’

  • ‘A strong team that includes young, but clearly very well-prepared, associates.’

  • ‘Very intelligent and practical - available when needed.’

  • ‘High level of partner availability - pragmatic advice and attention to cost control.’

  • ‘Constantine Partasides KC is a well known litigator, who is extremely sharp and convincing.’

  • ‘Gaëtan Verhoosel KC is a professional who is noted for his technical knowledge and agile responses, which constitute important support when making decisions.’

  • ‘Leilah Bruton has amazing attention to detail and writes beautifully.’

Key clients

  • ConocoPhillips
  • ContourGlobal
  • Elliot Associates
  • Eni
  • ExxonMobil
  • Kingdom of Bahrain
  • PETRONAS
  • Sultanate of Oman
  • Sacyr
  • TotalEnergies
  • Trafigura
  • TGF

Work highlights

  • Obtained a favourable and highly-publicised award on behalf of Elliott Associates in an investment treaty claim against the Republic of Korea, the dispute arising from a corruption scandal that led to the imprisonment of the then-President of Korea.
  • Acting for Eni in a high-stakes and politically-sensitive dispute against the Federal Government of Nigeria, involving allegations of corruption and claims under the Netherlands-Nigeria bilateral investment treaty.
  • Assisiting ConocoPhillips with the defence of a historic $8bn ICSID award against attempts by the Republic of Venezuela to have it annulled.

Lawyers

Hall of Fame
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Leading associates
Leading associates with regular involvement in their team's key work, and recognition from peers or clients as being ones to watch.
Leading partners
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Next Generation Partners
Junior partners with significant recognition from clients and peers in the market and key roles on multiple matters.

Practice head

The lawyer(s) leading their teams.

Constantine Partasides KC, Gaëtan Verhoosel KC

Other key lawyers

Reza Mohtashami KC, Manish Aggarwal, Leilah Bruton, Hamid Abdulkareem, Farouk El-Hosseny, Ridhi Kabra