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Fietta LLP is a unique law firm, specialising in public international law. Since its launch in 2015, Fietta has grown to 13 fee-earners, all of whom are specialists in public international law and international investment disputes.

The firm: Fietta brings together a team of true PIL experts at the forefront of their fields and an impressive track record of winning cases. At all levels of the firm, its lawyers have broad-based experience advising States, international organisations, private clients and individuals across a range of international law matters. Fietta lawyers have acted as counsel on some of the largest and most important PIL disputes of the past two decades, across a multitude of international court and tribunal settings. The firm’s advisory practice for State clients has encompassed some of the most sensitive PIL issues.

All of Fietta’s lawyers have previously practised at leading global or ‘Magic Circle’ firms. Most of its lawyers have also worked within governments, international courts or intergovernmental organisations and have postgraduate degrees in public international law. The firm regularly works as co-counsel with leading global firms, local and regional firms around the world and members of the public international law Bar.

Types of work undertaken: The firm’s experience includes investor-State dispute settlement; maritime, sovereignty and land boundary disputes; international environmental law; international organisations; and human rights.

Disputes: Fietta’s lawyers have represented clients in State-to-State, investor-State and other international law disputes for more than 20 years, at the pinnacle of PIL practice. Fietta’s lawyers have acted successfully as counsel to both investors and States in investment treaty arbitrations under all major institutional rules, winning some of the most substantial or notable awards in recent history; in State-to-State boundary and sovereignty disputes; and in leading human rights, environmental, sovereign immunity and other cases before the European Court of Human Rights, international and domestic courts.

Advisory: Fietta’s lawyers have advised States, international organisations, multinational corporations, NGOs and private individuals on public international law questions, including: treaty negotiation, interpretation and application; land sovereignty and maritime boundary negotiations; bilateral and multilateral investment treaties (including the Energy Charter Treaty); human rights; international environmental law; diplomatic and sovereign immunity; State succession; transboundary pipelines; and economic sanctions.

  • Number of UK partners: 2
  • Number of other UK fee-earners: 11
  • Breakdown of work %
  • Public international law - advisory: 30
  • Public international law and international arbitration - contentious: 70

  • Languages
  • French
  • Spanish
  • Italian
  • Russian
  • Bulgarian

Above material supplied by Fietta LLP.

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