FONS Family Office Network Service

FONS Family Office Network Service

FONS Family Office Network Service was established in 2004 by Olivier Brunisholz. The firm grew from the legal and fiduciary practices of its founding partners, whose professional earnings form the core of the client capital it now oversees. FONS allocates across real estate, infrastructure, hedge funds and secondaries. It executes direct co-investments and participates in seed through Series C rounds. Confirmed holdings include mixed-use properties in France, the JR art collection managed through Unframed SA, and European Property Holdings positions. Activity spans Europe and North America. The firm lists no disclosed AUM figure and maintains a Geneva headquarters with no additional offices reported. Olivier Brunisholz also serves on the board of Valartis Group, where he collaborates with chairman Gustav Stenbolt. Guillaume Lejoindre, a former Société Générale Private Banking executive, sits on the FONS board. Philanthropic vehicles include the LINK & FILM FOUNDATION and Bureau Central d'Aide Sociale. FONS operates through a network of Swiss legal and banking relationships rather than a single-family mandate. This structure allows it to serve multiple entrepreneurial families while retaining control over cross-border succession and art-related intellectual property vehicles.