Private EquityRIA · CRD 147353SEC-RegisteredPrivate Fund Adviser

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Flexstone Partners

Flexstone Partners is an SEC-registered investment adviser in New York, NY, registered since 2008.

Flexstone Partners

Flexstone Partners is an SEC-registered investment adviser in New York, NY, registered since 2008. The firm manages $5.3 billion in assets, with $1.9 billion on a discretionary basis. It has 28 employees and 9 investment advisers.

General information

Firm type

Private Equity

Year founded

AUM

$12.4 billion (per the firm, January 2026)

Location

Region

North America

Country

United States

City

New York

Corporate office

575 Fifth Avenue, 22nd Floor, New York, NY 10017, USA

Additional offices

Paris, France · Geneva, Switzerland · Singapore

Sector focus

Private EquityReal EstatePrivate CreditInfrastructure

Frequently asked questions

How does Flexstone Partners source its small- and mid-cap deal flow?

Flexstone’s team of over 65 professionals reviews 600-plus investment opportunities globally each year, according to the firm. Presence in New York, Paris, Geneva, and Singapore provides local origination networks in North America, Europe, and Asia. Deal flow comes from long-standing general partner relationships and direct prospecting in the sub-$1 billion fund market.

Is Flexstone Partners an independent firm or part of a larger financial group?

It operates as an affiliate of Natixis Investment Managers, one of the world’s largest asset managers, which provides access to global resources and infrastructure. Despite the parent-subsidiary relationship, Flexstone maintains an entrepreneurial investment culture and autonomy in manager selection. The firm’s structure separates investment decision-making from the parent’s balance sheet.

What is Flexstone’s approach to ESG integration?

Flexstone has been a signatory to the United Nations Principles for Responsible Investment since 2014, per its website. It seeks to invest in managers and companies that manage environmental impact, adhere to fair labor standards, and follow sustainable business practices. ESG analysis is part of its manager due-diligence and ongoing monitoring processes.

Does Flexstone manage commingled funds or only separate accounts?

Flexstone tailors portfolios to the distinct mandates of each client, as stated in its materials. This typically involves building customized separate accounts with specific allocations to private equity, real estate, private debt, or infrastructure. The firm does not market standard commingled products as its primary vehicle.

What types of private investments does Flexstone target?

The firm invests across private equity, real estate, private debt, and infrastructure. Its specialization lies in the small- and mid-cap segment, which it identifies as a hard-to-access area offering greater inefficiencies. Exposure is built through primary fund commitments, co-investments, and secondary transactions globally.

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