Althéo Partners

Overview

Althéo Partners is a French Société par actions simplifiée with €10,000 in capital and registration with the Paris RCS under SIREN 810 662 841.¹ The firm works with families, patrimonial companies, congregations and foundations in France and internationally.¹⁴ It is a member of the Association Française du Family Office and follows its ethics charter.¹³

History

Alexandre Boissarie is identified as the firm’s founder and Family Partner.²⁴ The firm states that its operating partners own the business.¹¹

Leadership

Alexandre Boissarie is listed as Family Partner and Founder.²⁴ Bérengère Garand-Clavel and Olivier Roux de Bézieux are listed as Family Partners.²⁵ Domitille Dufour and Malo Legouin are listed as Family Officers. Lucie Landowski is listed as Real Estate Officer. Agnès de Mortemart is listed as Family Lifestyle Manager.²⁶ Alexandre Boissarie is also named publication director and a Mandataire d’intermédiaire en opérations de banque et en services de paiement.²⁴

Services

Investment management covers listed assets, real estate, private equity, tangible assets, art, forests and vineyards, with portfolio monitoring, allocation reviews and regular reporting.¹⁷¹⁸

Wealth planning and administration include patrimonial audits, strategy work, legal and administrative assistance, investment formalities, household employee management and insurance administration.¹⁶¹⁹

Governance and philanthropy work includes succession planning for family businesses, next generation projects, mediation and family relationship support.²⁰

Real estate assistance covers purchases and sales, residences, investment property, rental oversight, works monitoring and DPE formalities. The firm describes access to properties in Paris, elsewhere in France and internationally.²¹²²

What the firm offers

• Investment management
• Financial planning
• Estate planning
• Philanthropy
• Family governance and education
• Administration and bill pay
• Risk and insurance
• Private and alternative investments
• Cross-border planning

Client focus

Althéo Partners serves entrepreneurs, heirs, holding companies, foundations and associations.¹⁴ Its work also covers families, patrimonial companies, congregations and foundations across France and international settings.¹⁴ The Paris and Brussels team works with lawyers, notaries and other recognized experts.²⁷

Investment philosophy and approach

The firm says its work emphasizes rigor, transparency, confidentiality, independence, responsiveness and alignment of interests.²³ It presents its role as coordinating financial, legal, tax, real estate, asset, liability, philanthropy and collections matters for families and related organizations.¹⁴ Althéo Partners identifies as a Conseil en Investissements Financiers registered with ORIAS and affiliated with ANACOFI CIF.⁵ It also identifies as an insurance intermediary and broker, and as an IOBSP operating under a client mandate.⁷⁸

FAQs

Related resources

• LocationMultifamily offices in Paris

  This page helps readers compare multifamily offices serving Paris and nearby clients. It can support questions about investment management, estate planning, family governance, and administration when considering a firm with teams in Paris and Brussels and clients that include families, entrepreneurs, heirs, and holding companies.

• Network siteOffshoreTrusts.com

  These guides explain how offshore and international trusts may fit into cross-border asset planning. They give families, entrepreneurs, and heirs topics to discuss with advisers about ownership structures, succession, tax coordination, and philanthropy across France, Belgium, and other jurisdictions.

• Network siteFamilyOffices.com

  FamilyOffices.com offers resources and a community focused on single family offices and wealthy families. Readers can use it to consider governance, education, reporting, administration, and investment oversight when assessing how a multifamily office might support a family, foundation, association, or business owning household.

• GuideHow multifamily offices invest

  This resource outlines common ways multifamily offices approach portfolios, including public markets, private investments, alternatives, liquidity planning, and risk controls. It can help a business owner or family prepare questions about investment management, wealth planning, and how portfolio decisions connect with longer term family objectives.

• Similar firmsAltride Family Office
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  Profiles of Altride Family Office, B. Durand Capital Partners, and Côme Maison Financière provide nearby points of comparison on this site. Reviewing these firms can help readers organize questions about client types, investment management, estate planning, cross-border needs, family governance, and administrative support.

Sources

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Claim or correct this profile

This profile is a factual summary written in our own words from public sources. It is for information only. It is not an endorsement, rating, ranking or recommendation, and it is not investment advice. MultiFamilyOffices.com is not affiliated with the SEC or with this firm unless stated. Form ADV figures are self-reported by the firm.