Pleion Wealth Partners and Probus Group have combined to form an independent business with CHF4bn (£3.18bn, $4.38bn, €3.7bn) of assets under management and 200 employees worldwide.
Patrick Héritier, currently chief executive of Pleion, will take over the management of the newly established firm in Switzerland, subject to regulatory approval.
All group companies will be brought together under the current Swiss holding company Probus Holding, while the wealth management company Probus Compagnie will be merged into Pleion.
The business will have six offices in Switzerland in Geneva, Bern, Nyon, Sion, Verbier and Zurich, as well as an extensive international presence in Bangkok, Dubai, Luxembourg, Mauritius, Monaco and Moscow through group entities.
It will have four main shareholders; Georges de Preux and Bernard Bonvin, from Probus, and Antoine Darioli and Héritier from Pleion.
The transaction remains subject to the approval of Swiss Financial Market Supervisory Authority (Finma) and regulators.