John is a solicitor qualified to practise in three jurisdictions: Northern Ireland, England and Wales and the Republic of Ireland. John is also admitted as a Barrister and an Attorney in Bermuda. With particular expertise in corporate, commercial and intellectual property matters, his career has included a number of years spent in private practice as well as in-house. John also has a particular interest in advising clients in the property, energy, retail, hospitality, sport and general contracting industries.
- Corporate law
- Commercial law
- Mergers and acquisitions
- Private equity
- Intellectual property
- Acted in the acquisition of a portfolio of commercial buildings in Belfast city centre for Kilmona Group.
- Advised on a new £100m health hub to be located at Kings Hall Belfast.
- Acted in the £34m acquisition of the business and assets of Straben Developments Limited for Straben Limited.
- Acted in the acquisition of a £180m distressed property development debt from Ulster Bank Limited.
- Acted in the acquisition of £90m of debt from Cerberus Capital Management owned spv for Rhino Investment Management LLP.
- Acted in the acquisition of Warner Chilcott plc for $3.1bn in December 2003.
- Advised on the sale of the entire issued share capital of Belfast Distillery Limited to a US-based purchaser.
- Advised Causeway Aero Limited on its £850,000 shareholder fundraising (during lockdown).
- Advised Kilmona Group on its £90m refinance with Fairfield real estate.
- Advised Straben Limited on its £30m refinance of Adelaide Exchange, Belfast with Danske Bank.
- Advised the estate of the late George Best on the protection and exploitation of its intellectual property including the registration of George Best trade marks and negotiated a commercial exploitation agreement with IMG.
- Advised Galgorm Castle Golf Club on the hosting of a European PGA Challenge Tour event – the NI Open.
Please note: The experience list above may include examples of work completed prior to joining Keystone Law.
Recognised by the Legal 500 2021 for Northern Ireland: Corporate and M&A
Recognised by the Legal 500 2020 for Northern Ireland: Corporate and M&A
“John McMahon has a wealth of experience and an eye for the commercial priorities in every transaction.” Legal 500 2020
“John McMahon and his team are experienced practitioners. They know what the issues are and flag them for discussion in advance. They are not “learning on the job” – they know the job inside out. Experience, locally, nationally and internationally, means that they don’t lead clients down cul-de-sacs.” Legal 500 2020
‘A very dedicated and capable team who integrate across various aspects of the business. Led by John McMahon, they are both pragmatic and commercial, and very focused on delivering for their clients.‘ Legal 500 2020
Recognised by the Legal 500 2018 for Northern Ireland: Corporate and Commercial and Northern Ireland: Commercial Property
John McMahon is recognised by the Legal 500 2017.
John qualified as a solicitor in 1993. Prior to joining Keystone Law in 2017, he worked at the following firms:
- McMahon McKay