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Simmons & Simmons

Work +44 20 7628 2020
Fax +44 20 7628 2070

Charles Mayo

Work 020 7825 4410
Simmons & Simmons

Work Department

Corporate/corporate and commercial.


Charles advises a wide range of leading listed companies, investment banks and brokers. He specialises in public/private partnerships, equity capital markets, and mergers and acquisitions transactions. Charles regularly advises on the listing, disclosure, prospectus and transparency rules and participates in a series of workshops on these rules with the Financial Services Authority and the London Stock Exchange. Charles also specialises in advising on the legal aspects of corporate governance and compliance, including advising on the Bribery Act. He also has particular experience in the life sciences, aerospace and defence and transport sectors. Charles’s recent experience includes: advising the Ministry of Defence on the public/private partnership with Carlyle in relation to QinetiQ, including the £1.3bn IPO of QinetiQ on the Official List, the first UK Government IPO for nearly a decade; advising the selling shareholders of Specifar Pharmaceuticals S.A., a generic drug developer, on the US$562m acquisition of the company by Watson Pharmaceuticals Inc.; advising on the ‘virtual’ acquisitions and AIM IPOs of Center Parcs and of Anker and on the IPOs of Plethora (UK), Endace (NZ) and Asian Citrus (China), Sinclair Pharma on its Main Market listings in London and Paris, Japaninvest on its Tokyo listing and CLSA as sponsor of the Hong Kong listing of RCG, the first Hong Kong Stock Exchange listing of an AIM-traded company; and advising the UK Government on the Energy Technology Institute, a not-for-profit public/private partnership to research lower carbon energy to help tackle climate change. Charles and Nick Benwell (litigation partner) led the team that won the Innovation in Anti-bribery and Corruption award at the Financial Times European Innovative Lawyers Awards 2011. Charles was also behind the firm winning the 2011 Best Regulatory Law Firm of the Year Award at the Thomson Reuters Accelus 7th Annual Compliance Awards. The Legal 500 UK highlighted Charles as a ‘Leading Individual’ in the pharmaceutical and biotechnology sector.


Partner 1992; Hong Kong office 2007-09; member CBI Companies Committee and Primary Markets Group of the London Stock Exchange; recently appointed member Legal Experts Network of the Association of the British Pharmaceutical Industry.

London: Corporate and commercial

Flotations: small and mid-cap

Within: Flotations: small and mid-cap

Simmons & Simmons' AIM work has been on the increase since the arrivals in 2014 of Patrick Graves and Jocelyn Ormond from Osborne Clarke and DAC Beachcroft LLP respectively. Although the firm is particularly well-known for its work in the Main Market arena, it is equally as active in AIM transactions. Chris Horton leads the team, which has a strong focus on acting for companies, NOMADs and brokers in matters connected with the TMT (including fintech) and healthcare/life sciences  sectors. In 2017, Ormond, supervising associate Dan Whitewood and others acted for the shareholders of Intelligent Ultrasound in the disposal of the company to AIM-listed entity MedaPhor Group Plc. Charles Mayo advised Stifel Nicolaus Europe (as NOMAD and joint broker) and WG Partners (as joint broker) on the dual-listing on AIM of international diagnostics company Novacyt (which was already listed on the Euronext Growth Market). Other clients include 1PM, Rex Bionics Plc, Numis Securities and Petards Group. Managing associate Stephanie Featherstone is recommended.

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London: Public sector


Within: Healthcare

Simmons & Simmons¬† handles complex corporate healthcare transactions and advisory work for asset management and private healthcare providers. The team has a ‚Äėhuge depth of experience‚Äô whole and practice head Jocelyn Ormond¬†is noted for his ‚Äėexcellent knowledge of the healthcare market and the legal and contractual frameworks‚Äô, his recent instructions include advising Intelligent Ultrasound and Weight Partners Capital on complex M&A matters. Corporate partner Charles Mayo¬† is highly recommended for public/private partnership arrangements.

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London: TMT (technology, media and telecoms)

Pharmaceuticals and biotechnology

Within: Pharmaceuticals and biotechnology

Simmons & Simmons is 'jam-packed full of the highest-calibre individuals' in the areas of transactions, patent litigation and regulations. Michael Gavey leads the team and is particularly prominent in handling the IP aspects of transactions. Charles Mayo is also a key figure and highly experienced in M&A and capital markets transactions. Other key members of the team include Scott Parker, who is an expert in patent litigation, and transactions specialist Lydia Torne. Rowan Freeland has retired.

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