
Connect
About
Paul MacMahon is an Associate Professor of Law at the LSE Law School and the Director of the Executive LLM Programme. His primary interests are contracts, commercial law, and international arbitration. Before coming to the LSE, Paul taught at Harvard and Cambridge. He studied at Oxford (BA, BCL, DPhil) and Harvard (JD), and served as a law clerk in the United States for Judge Guido Calabresi and Judge John Gleeson. Paul also worked as a litigation lawyer in New York City and remains a member of the New York Bar. In addition to teaching at LSE, Paul is a regular Visiting Professor at Católica Global School of Law in Lisbon. His work has been cited in the English and Singapore Courts of Appeal, and he has served as an expert on English law in foreign court proceedings.
Research
Research Interests
- Contracts
- Commercial Law
- International Arbitration
Publications
- 'Constructing Frustration' in Paul Davies and Magda Raczynska, Contract Law and the Unexpected (Hart, forthcoming 2026)
- 'The Englishness of English Contract Law' European Review of Private Law (forthcoming 2026)
- 'The Effect of Prohibitions on Assignment on Attempts to Grant Charges' Journal of International Financial and Banking Law (forthcoming 2026)
- ‘Reliance’ in Mindy Chen-Wishart and Prince Saprai (eds), Research Handbook on the Philosophy of Contract Law (Elgar, 2025)
- 'Compensation After Cancellation for Sellers' Negligent Delay' [2025] Lloyd's Maritime and Commercial Law Quarterly 29
- 'The Costs of Contractual Uncertainty' (2024) Modern Law Review 404
- ‘Common law responses to the Unidroit Principles of International Commercial Contracts’ inKöhler, Gulati and Thomas, (eds.) The Elgar Companion to UNIDROIT. Elgar Companions to International Organisations series (Elgar, 2024)
- 'Conditional Agreements and Arbitration Law's Separability Principle' [2023] Lloyd's Maritime and Commercial Law Quarterly 1999
- 'Rethinking Assignability' (2020) 79 Cambridge Law Journal 288
- 'Contract Law's Transferability Bias' (2020) 95 Indiana Law Journal 485
- 'Conflict and Contract Law' Oxford Journal of Legal Studies (2018) 38, pp.270-298
- 'Soft Adjudication' Administrative Law Review (2017) 69 pp.529-584
- 'The Revolutionary War Prize Cases and the Origins of Diversity Jurisdiction' Buffalo Law Review 63 (2015): 477-547 (with Deirdre Mask)
- 'Good Faith and Fair Dealing as an Underenforced Legal Norm' Minnesota Law Review (2015) 99 (6) 2051-2110
- 'The Inquest and the Virtues of Soft Adjudication' Yale Law and Policy Review, 2015
- 'Proceduralism, Civil Justice, and American Legal Thought' 34 University of Pennsylvania Journal of International Law 545-610 (2013)
- 'Self-Service Search Warrants and International Terrorism' 1 Ir. L.J. 2 (2012)