Mesirow buys flexPATH's 3(38) book in second fiduciary deal

Mesirow Fiduciary Solutions, the outsourced fiduciary arm of Chicago-based Mesirow, has agreed to buy flexPATH Strategies' plan-level 3(38) investment management business. The deal is expected to close in the fourth quarter of 2026, InvestmentNews reported. It is the firm's second acquisition in the outsourced fiduciary market this year.

The purchase covers a book of work built on custom portfolio construction at the level of the individual plan. Under ERISA, a 3(38) fiduciary takes discretionary authority over a plan's investment decisions, and a meaningful layer of fiduciary liability moves off the plan sponsor and its adviser. What remains for the adviser is the relationship work: plan design, participant education, and the client conversations that sit around the money.

flexPATH's franchise grew at the point where that compliance structure meets personalized portfolio construction. Its portfolios are built for each plan rather than pulled from a shared model lineup. That suits sponsors who want bespoke strategies without surrendering the liability transfer a 3(38) arrangement provides.

Earlier in 2026 Mesirow bought Precision Fiduciary Partners, a platform with $23 billion in assets. Mesirow Fiduciary Solutions already ran $141 billion on its own. Together the two businesses oversee roughly $164 billion in assets under management and advisement. The combined platform supports about 10,000 financial advisers nationwide. The flexPATH acquisition extends that reach further into the defined contribution market as sponsor demand for outsourced fiduciary services continues to rise.

Michael Annin, president of Mesirow Fiduciary Solutions, described the purchase as a combination of flexPATH's specialized portfolio line with the platform's infrastructure. "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," he said.

InvestmentNews frames the transaction as part of a consolidation wave across retirement plan services. Plan sponsors face mounting regulatory scrutiny and expect more accountability from providers. That has made outsourced fiduciary models attractive to buyers and sellers alike. Mesirow's two purchases in one year put it on the buying side of that wave.

For plan sponsors, the deal turns one independent 3(38) specialist into part of a larger platform. Mesirow becomes a bigger presence in a consolidating market. The integration work starts at closing: folding flexPATH's plan-by-plan portfolio construction into a business built for institutional scale, and showing a 10,000-adviser distribution channel how to sell a bespoke product line.