Elsa Lourdeau
Business & SSE Lawyer in Lyon
Plexus Avocats is a law firm in Lyon based on a simple conviction: business law can be a tool, provided that it is handled rigorously and in the right direction.
A lawyer in Paris and then a member of the Lyon Bar since 2011, Elsa Lourdeau has built a unique firm at the intersection of business law, the Social and Solidarity Economy and dispute resolution. A tailored, long-term approach for business leaders and organizations that refuse to choose between legal rigor and impact-driven ambition.
What drives me? A commitment to rigor. A focus on the people behind the cases. And the conviction that the law must adapt to projects, not the other way around. Consistency, and depth.
Why "PLEXUS"?
A name that perfectly reflects the firm’s philosophy: bringing different worlds together, connecting different perspectives, and weaving legal solutions at the intersection of business law, the Social and Solidarity Economy, and impact-driven projects.
We hear the “plex” in complex, a nod to the philosophy of Edgar Morin, because the matters we advise on are often complex — and so is society itself. We can distinguish the “lex”, a subtle nod to the law. And we find the solar plexus: a central network of interconnected nerves in the human body, the seat of decision-making, and a point where energies converge. It is no coincidence that Plexus Avocats’ clients are leaders and builders.
A name that resonates with a working philosophy: network, cooperation, interconnection between the legal and the strategic. Between the structure and the project.
Associate Lawyer · Lyon Bar · Business Law & SSE
Elsa Lourdeau,
Background and Expertise
A lawyer since 2011, with over fifteen years of practice at the Paris and Lyon Bars, Elsa Lourdeau has built a strong practice in business law (commercial litigation, contract law, corporate law, and real estate law) before progressively specializing in advising impact-driven organizations and those operating in the Social and Solidarity Economy. Today, she advises both business leaders and cooperatives, associations, foundations, endowment funds, and founders of hybrid projects operating at the intersection of both profit and non-profit sectors.
Her skills brings together three areas of expertise that small, independent law firms rarely combine: strong technical expertise in business law, an in-depth understanding of SSE organizations and their legal and operational realities, and training in alternative dispute resolution methods, including settlement negotiations and mediation.
This combination is not a marketing positioning; it reflects the reality of the matters she handles, which often sit at the intersection of these three areas.
Education and Qualifications
Holding a Master II in Private International Law from Université Paris 1 Panthéon-Sorbonne and an LL.M. (Master of Laws) from King’s College London, one of the world’s most highly regarded law schools, Elsa Lourdeau‘s legal education was grounded from the outset in a demanding international environment. This background enables her to advise on matters involving foreign parties or international partners, with the same level of rigor in both French and English.
Trained in settlement negotiations in London and in mediation at the Centre Interprofessionnel de Médiation et d’Arbitrage de Lyon (CIMA, 2022), she considers alternative dispute resolution (ADR) an integral part of her practice, not as a last resort, but as a first-line option when appropriate.
Commitments
Elsa Lourdeau is a member of the SSE Commission of the Bar Association of Lyon and the Associations and Foundations Commission of the ACE (Association of Corporate Counsel).
These institutional roles are not merely honorary: they involve actively monitoring legislative and regulatory developments that directly affect the firm’s clients, including changes to the legal framework governing purpose corporations, developments in sponsorship and charitable giving tax rules, reforms to alternative dispute resolution mechanisms, and new forms of cooperative organization.
Participating in these professional bodies also means helping the legal world’s understanding of SSE structures and impact-driven bussinesses to evolve from within the profession.
Since March 2026, Elsa Lourdeau has also been a member of the jury of the AURA Regional Committee of France Active Investissement, contributing her expertise to support the wider movement of purpose-driven entrepreneurs.
Approach and Methodology
Elsa Lourdeau approaches conflicts as problems to be solved, not simply as proceedings to be litigated. Her approach: listen before advising, ask questions before drafting, then work with her clients to build the legal solution that truly fits their situation.
This approach is built on continuity in the client relationship. Plexus Avocats’ clients do not seek legal advice only when issues arise: they integrate legal counsel into their strategy, anticipate legal issues before they arise, and adapt their approach as their organization grows. The objective is to make the law a governance reflex, not an emergency intervention.
EXTENDED TEAM
Outsourced Administrative & Financial Director · Firma Mentum
Visnia BOCCON-GIBOD
A graduate of NEOMA Business School, Visnia Boccon-Gibod began her career as an auditor at Arthur Andersen before spending nearly twenty years as Finance and Administration Director for service-sector SMEs, and later as Secretary General of law firms including LexCase and DELSOL Avocats. In 2025, she founded Firma Mentum to put this expertise at the service of entrepreneurial lawyers.
Visnia works with Plexus Avocats on a part-time basis, overseeing the firm’s operations, cash-flow management, administrative matters, bookkeeping preparation, and day-to-day organization. Her experience as a CFO and her precise knowledge of the realities of law firms allow Elsa Lourdeau to focus on her core business with the serenity that only rigorous management can guarantee.