Housing an ‘responsive, practical, and solutions-focused’ group, Mason Hayes & Curran LLP is recognised for its market-leading capability in executing complex, high-stakes disputes, drawing on its deep bench of expertise across the financial services, tech, life sciences, built environment and energy sectors. Jointly leading the group is Maurice Phelan, a ’commercially astute’ litigator who is noted for handling high-value shareholder, contractual and tortious disputes, alongside Gerard Kelly, who maintains a strong reputation in the IP space, handling patent, passing off, trade mark, copyright and design litigation. Declan Black is a key contact for business disputes, while Colin Monaghan frequently handles multi-party disputes before the High Court. Liam Guidera is skilled in investigations and white-collar crime matters, and Peter Johnston is well-equipped to act on matters involving financial services litigation and shareholder disagreements. Norman Fitzgerald joined the team in September 2025 from Eversheds Sutherland.
Legal 500 Editorial commentary
Testimonials
Collated independently by Legal 500 research team.
- ‘Conor O'Leary is a pleasure to work with and is particularly skilled in managing complex, multi-party litigation. Conor has a great understanding of the client's needs and of the litigation strategy required to achieve the best outcome for the client.'
- ‘Lisa Joyce and Domhnall Breathnach are two stand out partners in MHC. I have worked with them in a vast array of difficult cases. They show immense dedication to their work and bring a calm, organised, focused, strategic and clear approach to the difficult cases they manage to ensure that their clients achieve the very best outcomes.'
- ‘I work regularly with Colm Farrell who is simply a pleasure to deal with. His advice is commercially focused, delivered ahead of time and always tailored to fit with our company's agenda. He is an asset to have on your team and we are so lucky to work with him.'
- ‘Maurice Phelan and any of the partners I interacted with from Mason Hayes Curran all displayed a remarkable ability to quickly grasp the “big picture” holistic overview of complex commercial situations whilst simultaneously retaining meticulous attention to detail.'
- ‘Good, commercially sound firm. Good strength in depth from Maurice Phelan, James Morrin, Judith Riordan, Declan Black and Peter Johnston.'
- ‘Maurice Phelan is extremely assured, commercially astute and provides market leading, client focused service.’
- ‘Stand out cross-department collaboration from Brian Johnston and Lisa Joyce, where matters require both advisory and contentious advice to be delivered with a single united 'voice'. As a client I have deep confidence and trust in the expertise of Brian and Lisa, who are highly valued counsellors by me and the wider in-house legal function.’
- ‘Colin Monaghan was the lead on my case and again was adept at gathering enough knowledge to understand the issues at hand. He was very accessible and prompt at dealing with the evolving case.'
- ‘Colin Monaghan and Anthony Strogen are both very pragmatic, calm and excellent to deal with. Peter Johnson is intelligent and commercially minded.'
Key clients
- CDB Aviation Lease Finance DAC
- Meta Platforms Ireland Limited
- SIS Media Limited
- Mitsui Sumitomo Insurance Company
- WhatsApp Ireland Limited
- William Hill Organisation Limited
- Coillte
Work highlights
Acted for CDB Aviation in its claim seeking an indemnity from 21 different insurers arising from losses sustained from the leasing of nine aircraft to various Russian airlines.
Acting for Meta in statutory appeal and judicial review proceedings before the Irish High Court challenging an enforcement notice issued by the Irish Data Protection Commission.
Acted for (i) SIS, and (ii) William Hill in Commercial Court proceedings against two individuals.
Lawyers
Leading partners
The strongest partners in their field, leading on market-leading deals and endorsed by peers and clients alike.
Practice head
Maurice Phelan; Gerard Kelly
Other key lawyers
Declan Black; Colin Monaghan; Liam Guidera; Peter Johnston; Anthony Strogen; Conor O’Leary; James Morrin; Judith Riordan; Peter Johnston; Colm Farrell; Lisa Joyce; Domhnall Breathnach; Nicholas Metcalfe; Norman Fitzgerald