Mesirow Fiduciary Solutions, the outsourced fiduciary arm of Chicago-based Mesirow, has struck a deal to acquire the plan-level 3(38) investment management business of flexPATH Strategies. The transaction, announced this week, is slated to close in the fourth quarter of 2026, marking Mesirow's second acquisition in the outsourced fiduciary space this year.
The move expands Mesirow's footprint in the defined contribution market, where demand for outsourced fiduciary services continues to climb amid heightened regulatory scrutiny. Upon completion, the combined entity will oversee roughly $164 billion in assets under management and advisement, including $141 billion from Mesirow Fiduciary Solutions and $23 billion from Precision Fiduciary Partners, which Mesirow acquired earlier in 2026. The platform supports approximately 10,000 financial advisors nationwide.
What flexPATH brings
flexPATH has built a specialized book of business centered on custom portfolio construction at the plan level—a niche that sits at the intersection of ERISA fiduciary compliance and personalized investment strategy. Under ERISA, a 3(38) fiduciary assumes discretionary authority over a plan's investment decisions, relieving plan sponsors and their advisors of a significant layer of liability. Advisors can offload investment management responsibilities to the fiduciary manager, freeing them to focus on participant education, plan design, and client relationship management.
Michael Annin, CFA, president of Mesirow Fiduciary Solutions, said the deal is designed to broaden what the firm can deliver to advisors and their plan sponsor clients. "By combining flexPATH's established custom portfolio business with Mesirow's institutional scale, technology infrastructure and fiduciary expertise, we are further enhancing our ability to deliver differentiated retirement solutions," Annin said.
A year of fiduciary consolidation
The flexPATH acquisition reflects a broader consolidation trend across the retirement plan services landscape. As plan sponsors face mounting regulatory pressure and demand greater accountability from service providers, outsourced fiduciary models have attracted significant interest from both buyers and sellers. Mesirow's two deals in 2026 signal a deliberate growth strategy aimed at capturing that demand.
"The acquisition of flexPATH's plan-level 3(38) fiduciary business marks our second acquisition in the outsourced fiduciary space this year, demonstrating our bullish view of the outsourced fiduciary space," said Ketan Shah, chief strategy officer and general counsel at Mesirow.
The consolidation of fiduciary service providers raises practical questions about continuity, service levels, and the direction of fees, particularly as larger platforms absorb smaller, more specialized players. Mesirow, founded in 1937 and still employee-owned, has positioned itself as a firm with the institutional infrastructure to absorb these businesses without disrupting service to existing advisor relationships.
For advisors, the deal underscores the growing importance of fiduciary services that extend beyond investment management into areas like provider searches. It also comes as inflation prompts more workers to delay retirement, adding pressure on plan sponsors to deliver robust retirement outcomes. Meanwhile, the broader RIA M&A environment remains active, with deals like Aspen Standard Wealth's acquisition of Denver Private Wealth highlighting continued consolidation across wealth management.
