The 401(k) Fight Now Starts Before the Recordkeeper Is Chosen

The fight for the 401(k) plan now starts before a recordkeeper is picked. One August week produced two examples. OpenArc, an open-architecture retirement advisory firm, launched a recordkeeper search practice that acts as an independent fiduciary for plan sponsors. Mesirow agreed to buy flexPATH Strategies' 3(38) fiduciary book, its second acquisition of that kind in 2026. OpenArc is building the top of the funnel itself. Mesirow is buying it. In both cases an adviser with fiduciary standing sits between the sponsor and the recordkeeper before the provider contract is signed.

OpenArc's new service handles request-for-proposal and request-for-information work for sponsors running 401(k), equity compensation, and health savings account plans. The firm takes no proprietary products and no revenue-sharing model. That absence is the pitch. A search run by a firm with no financial stake in which recordkeeper wins can present itself as the cleaner comparison. OpenArc argues the same position extends naturally to the ongoing fiduciary oversight that follows the search.

A search is a door. The firm running the request-for-proposal sits with the sponsor while the plan's investment menu, fee schedule, and service model are still open. That is where 3(38) oversight gets sold, and OpenArc says plainly that the search feeds its fiduciary business. The recordkeeper selection sets the platform the plan will run on for years. Win the search and you win the next conversation.

Mesirow's flexPATH purchase is the same trade from the other side. flexPATH's book is plan-level 3(38) business, where the adviser holds discretion over the investment menu. It folds into a $164 billion fiduciary platform. Mesirow is buying relationships where it already controls the menu; the assets under administration are secondary. This is its second fiduciary acquisition of 2026, and the pace suggests Mesirow is deliberately assembling plan relationships.

The mechanics differ. OpenArc is adding a service line with no disclosed acquisition cost. Mesirow is paying for an established book. The destination is the same, though. The adviser owns the relationship with the sponsor, not the recordkeeper, and that relationship now begins at the selection stage.

Recordkeeper searches have long been procurement work, handled by benefits consultants or run through the incumbent's own RFP response. Making the search itself an independent fiduciary service changes the sequence. The adviser now shows up while the sponsor is choosing which platform will hold the assets for the next contract cycle, not after the recordkeeper has installed the plan.

That sequencing carries the tension. A search firm with no proprietary products and no revenue sharing has one set of incentives. A search firm that later wins the 3(38) mandate has another. Whether sponsors get a better outcome from that handoff is still open. OpenArc's launch doesn't settle it, but the structure puts the question front and center.

The revenue-sharing point changes the economics of the search. Recordkeepers commonly pay revenue to plan advisers. A search firm that refuses those payments can compare providers without that bias. The sponsor then asks a new question: if the search firm also wants the 3(38) mandate, is the comparison still clean? The answer depends on how the firm sequences the search and the fiduciary work.

Mesirow's path is different. Buying a 3(38) book puts it directly into the ongoing fiduciary role. The flexPATH plans arrive with relationships already in place, and those relationships were built around discretion over the menu. A $164 billion platform gives Mesirow scale to negotiate with recordkeepers, but the sponsor relationship is the more durable asset. Plan sponsors rarely change recordkeepers without a reason. Holding the fiduciary mandate is the stickiest seat in the plan.

PWD's deal log lists the OpenArc launch and the Mesirow-flexPATH announcement on August 14. The same-day timing doesn't prove coordination. It does show the market's attention moving to the start of the plan lifecycle. The date matters less than the direction.

The menu is the asset in a defined-contribution plan. The recordkeeper holds the dollars and runs the platform. The fiduciary that selects and replaces the funds controls what participants can buy and what sponsors pay. That is why the fight is moving to plan design. OpenArc's search practice and Mesirow's book put advisers in the room when the menu is being written, not after it has been set.

For plan sponsors, the choice is sharper than it looks. A search firm with no revenue-sharing model may produce a more objective recordkeeper comparison. But if that same firm then becomes the 3(38) fiduciary, the sponsor has given the person who chose the provider the power to oversee the menu. There is no conflict on its face. That may be the point. The question is whether the two roles are disclosed and priced separately.

The next test is conversion. If OpenArc turns search mandates into 3(38) relationships, and if Mesirow keeps buying fiduciary books at this pace, the recordkeeper's role in plan design shrinks further. The recordkeeper will still run the platform. The adviser will own the decisions. That is the trade August put on the table.