State Street Corporation (NYSE:STT) today announced the expansion of its nearly 40-year relationship with Thornburg Investment Management, Inc, providing end-to-end servicing support for Thornburg’s new ETF share classes as the firm broadens access to its active, high-conviction investment strategies.

Thornburg is a privately owned, global investment firm managing approximately $57 billion in client assets1 as of March 31, 2026. Headquartered in Santa Fe, New Mexico, the firm is known for its disciplined, research-driven approach across equity, fixed income, multi-asset, and alternative strategies, serving institutions, financial professionals, and investors worldwide.

Under the expanded mandate, State Street will deliver comprehensive ETF servicing for Thornburg’s new share classes, including custody, accounting, ETF basket creation, create-and-redeem order management, ETF settlement, transfer agency, and reporting. The announcement marks only the second active ETF share-class servicing mandate in the US, with State Street serving as provider, underscoring momentum among active managers seeking greater flexibility in how they deliver their strategies to investors.

The expansion builds on a relationship that began in 1987. Today, State Street provides full-service support across Thornburg’s product lineup, including mutual funds, ETFs, closed-end funds, and UCITS vehicles.

“Thornburg has a long history of delivering differentiated, actively managed strategies, and we’re proud to support the continued evolution of their ETF platform,” said Donna Milrod, chief product officer at State Street. “Our role is to provide the operational scale and flexibility that allows clients to focus on investment outcomes, while ensuring a consistent and seamless experience across fund structures.”

Thornburg first partnered with State Street to launch its initial suite of active ETFs in January 2025. The introduction of ETF share classes represents a natural extension of that platform, reflecting growing investor demand for choice and flexibility in accessing active strategies.

“State Street has been a trusted partner to Thornburg for decades,” said Mark Zinkula, CEO of Thornburg. “Their deep experience across fund structures and their ability to support the full ETF lifecycle positions them well to help us meet evolving client needs.”