US wealth manager enters Luxembourg in bid to create world’s largest family office

A US financial outfit is buying a pair of well known European rivals in a deal that the companies say will create the world’s largest multi-family office and one of the most formidable competitors in the Grand Duchy.

Corient, an American wealth management firm with $214 billion (€185 billion) in client assets globally, has said it would acquire Stonehage Fleming, a multi-family office and corporate services provider, and Stanhope Capital, a wealth management and investment advisory firm. It will be Corient’s first presence outside the US and will roughly double its total client assets.

After the deal closes, Stonehage Fleming and Stanhope Capital will rebrand under the Corient name and become its international operations, according to Hélie de Cornois, head of the family office division in Luxembourg at Stonehage Fleming.

The “transaction will create one of the world’s leading independent advisory firms and multi-family offices focused on the holistic needs of ultra and high-net-worth families and wealth creators,” de Cornois told the Luxembourg Times.

What does a family office do?

Family offices handle the investment and administrative affairs of wealthy individuals and families, often coordinating the services of other professionals such as bankers, lawyers and property managers.

Single family offices are dedicated to and controlled by one high-net-worth family, do not require a separate authorisation from the Grand Duchy’s financial regulator, the CSSF.

Multi-family offices are external service providers which look after several wealthy families and do require specific authorisation.

In an interview, de Cornois said it would be the world’s largest multi-family office, a claim Corient likewise made in a press release.

The takeover requires regulatory approvals in the 14 jurisdictions where Stonehage Fleming operates, de Cornois said. The firm is not speculating on when the acquisition might be finalised.

The value of the transaction has not been disclosed.

More than 80 staff in Luxembourg

The two European firms have a notable footprint in the Grand Duchy. London-headquartered Stanhope Capital Group merged with Luxembourg-based family office and wealth management advisory Arche in 2023.

Stanhope Capital’s Luxembourg business booked total turnover of €6 million, including €1.6 million in family office fees, according to its latest annual financial report. The firm posted total net profit of €1 million and had 20 staff members as of 31 December 2024.

Globally, Stonehage Fleming had $29.7 billion in assets under management, as of 30 September 2025, and $175 billion in assets under administration, as of 30 June 2025, de Cornois said.

Stonehage Fleming is headquartered in Jersey and has been operating in the Grand Duchy since 2011.

In the year to 31 March 2024, Stonehage Fleming’s Luxembourg business booked total net turnover of €7.3 million and posted a €1.3 million loss for the accounting year, including a €1 million write-down in assets.

Stonehage Fleming picked up a sizable amount of business when it acquired Maitland Luxembourg’s family office portfolio in 2022. It grew from seven employees five years ago to 62 this month, de Cornois stated.

Luxembourg family office business

“This is an extraordinary opportunity to create the world’s largest non-bank wealth management firm and multi-family office focused on high-net-worth and ultra-high-net-worth clients,” said de Cornois, speaking about the Corient acquisition with the Luxembourg press for the first time.

High-net-worth-individuals typically have a minimum of €1 million in liquid assets and ultra-high-net-worth clients generally have at least €30 million in investable assets.

De Cornois said Corient was a cultural fit with Stonehage Fleming and the deal “maintains the alignment of interests with the clients we serve.”

Corient said in the press release that it would extend its “private partnership model” and after the integration “more than 300” equity partners would “own and operate the firm.”

Corient will “complement our local offering with new services, particularly in the area of investment, to provide a one-stop shop in Luxembourg,” de Cornois said.

Transatlantic links

Having a presence in both Europe and US is increasingly important in de Cornois’s view, since there are “many European entrepreneurs who have succeeded in the US, but also many American families wishing to relocate to Europe or having European assets.”

The tie-up will help Stonehage Fleming expand its “cross-border support capability for families and entrepreneurs between the US and Europe,” he said.

De Cornois does expect further consolidation in the European family office sector. “Multi-family offices in Continental Europe are relatively recent. The oldest structures were created around twenty years ago, and their number has multiplied recently with the creation of numerous small boutiques,” he said.

“The main objective of a family office is to support families over time, across generations, with the necessary perspective and experience. The centuries-old experience of the Anglo-Saxon world, which originated these services, is a considerable and undeniable advantage for families. Few structures can ensure the necessary sustainability to support families over time; the IT challenges, data security, and cross-sector and cross-border expertise require a certain size.”

One reason the family office segment has been growing overall is because more professionals are moving across jurisdictions and moving more frequently during their working lives. Increased mobility is good for family office growth, he said.

“Changes of residence raise numerous new questions, ranging from choosing and enrolling children in school to civil and tax implications. Placements often need to be considered in light of the new country of residence. The jurisdiction of both the country of origin and the country of destination is crucial for coordinating the entire process. Experience gained from these situations provides valuable support to families facing such changes.”