

Public International Law
Allen & Overy advises national and international corporations, financial institutions, international organisations, governments and States on all contentious and non-contentious aspects of public international law. Our market-leading practice includes specialists in environmental law, regulatory compliance and risk management, dispute resolution, anti-bribery and corruption, anti-money laundering, public law, human rights and sanctions.
A&O’s public international law advisory work includes:
- The drafting and interpretation of international treaties and conventions
- Maritime, territorial and boundary rights
- State succession
- International sanctions regimes
- Privileges and immunities of States and international organisations
- Recognition of States and State succession
- Title to natural resources and international environmental law
- Use of force and international humanitarian law
- Space law
- Trade law
We also advise on contentious Public International Law matters, including State-to-State disputes under public international law, including boundary disputes, and have a market-leading investment treaty arbitration practice.
Our experts have acted as counsel before international courts and special tribunals, such as the Iran-US Claims Tribunal, and advised states on out-of-court strategies for dispute resolution, including before UN fora. We are also one of only a handful of law firms with experience of contentious World Trade Organisation proceedings.
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News & insights

Publications: 26 OCTOBER 2020
U.S. Commodity Futures Trading Commission issues final position limits rule
On October 15, 2020, the U.S. Commodity Futures Trading Commission (“CFTC” or “Commission”) voted to approve a final rule on position limits for commodity derivatives (“Final Rule”).
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Publications: 20 OCTOBER 2020
Germany is taking another step on the road to mandatory human rights due diligence legislation. In July, two federal ministries published a Term Sheet for a German “Federal Bill on the Strengthening…
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Publications: 12 MAY 2020
23 EU Member States sign an agreement to terminate intra-EU bilateral investment treaties
Further to the decision of the Court of Justice of the European Union (the Court) in Case C-284/16 Slowakische Republic v Achmea BV on 6 March 2018 (previously reported on here) (Achmea), 23 EU Member…
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Publications: 17 FEBRUARY 2020
U.S. Treasury implements Final FIRRMA Regulations
This week, new regulations promulgated by the U.S. Department of the Treasury (the Treasury) went into effect to finalize and comprehensively implement the Foreign Investment Risk Review Modernization…
Read moreAwards and achievements
- Tier One, Public International Law, Legal 500 UK 2019
- Band 1, Dispute Resolution, Global-wide, Chambers Global 2019
- International Arbitration Firm of the Year, Benchmark Litigation Asia-Pacific Awards 2019
- Best Arbitration Team of the Year in Spain and Portugal, 2019
Recognition
Allen & Overy LLP has superlative expertise across the full spectrum of public international law and related matters… Its 'outstanding and hardworking' team is experienced in state-to-state disputes before the International Court of Justice and tribunals under the jurisdiction of the Permanent Court of Arbitration, ICSID, the United Nations Convention for the Law of the Sea and other ad hoc bodies.
Legal 500 UK 2019, Public International Law
Has a great deal of experience acting for both claimants and respondents in investment treaty disputes…Wins further recognition for its thriving sanctions practice and expert advice on sovereign immunity, Energy Charter Treaty claims, WTO matters and EU law.
Chambers Global 2020, Public International Law
Highly regarded for its expertise in investment treaty arbitrations. Experienced in arbitrations acting both for and against sovereign states and government bodies.
Chambers Asia-Pacific 2020, International Arbitration, China
Highly rated for its skilful handling of investment treaty disputes on behalf of both sovereigns and investors.
Chambers Global 2019, Public International Law
They have a very strong practice and a deep bench of talent.
Chambers Global 2018, Public International Law
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Recent developments and emerging trends in international arbitration law and policy