09 Mar 2026
Squair strengthens its teams with the addition of two new partners
"Squair hires Marie Coussi as partner in Paris for its public law practice (environment and energy) and Jean‑Mathieu Luciani as partner in Aix‑en‑Provence for its corporate/M&A practice."
Marie Coussi practices environmental and energy law. She advises and represents private and public actors facing complex regulatory issues in both advisory and pre‑litigation or litigation contexts. Her work covers industrial environmental law (ICPE, contaminated sites and soils, chemical products, carbon quotas, sale and reconversion of industrial sites), the circular economy (waste, extended producer responsibility), biodiversity and protection of natural habitats (water, protected species, pollution control), and energy law (renewables, self‑consumption, energy efficiency). She also structures and secures projects contributing to the energy and ecological transition and advises organisations on social and environmental responsibility matters (CSRD, duty of vigilance, misleading commercial practices). In addition, she handles general administrative litigation, notably in regulated activities and immigration law. A member of the Paris Bar since 2020, Marie Coussi was previously a collaborator at international firms A&O Shearman and Eversheds Sutherland LLP. During her career she worked on a draft international treaty on environmental rights and was a finalist of the first Prix Badinter in 2025 on the subject of environmental democracy.
Jean‑Mathieu Luciani specialises in corporate law and M&A, advising managers and shareholders with a deal‑oriented practice covering audit and structuring, negotiation, drafting and securing transactional documents (agreements, warranties, shareholders’ agreements) and governance matters. He supports start‑ups, scale‑ups, SMEs and investors (business angels, investment funds/VC) on fundraisings and LBOs, including choice of instruments (preference shares, BSA, convertible bonds, etc.), structuring equity entry, negotiating rights in shareholders’ agreements and implementing incentive mechanisms (management packages) to align founders, managers and investors. He advises clients across France, combining local anchoring with market standards. Active in advising SMEs/ETI and investors since 2015 with an operational and pragmatic approach, Jean‑Mathieu Luciani joins Squair as a partner after practicing at the leading business firm Bignon Lebray, where he developed a demanding transactional practice serving French and international companies.