Many fiduciaries, including advisors to plan sponsors, had PIMCO’s funds on a “watch list” even before Gross decided to leave the firm he co-founded, indicating their dissatisfaction with the funds’ performance and the news of turmoil among top management, according to Henry Yoshida, co-principal of the Maresh Yoshida Group and an advisor to 401(k) plans.

Yoshida told Bloomberg News that the announcement of Gross’ departure will have real consequences on 401(k) plans. “Our group and many others will begin making recommendations to map assets from PIMCO to another fixed-income fund,” said Yoshida.

In a conference call Monday with analysts, PIMCO CEO Douglas Hodge said the firm is expecting client redemptions on the news of Gross’ departure, but that it is too early to tell how significant. Hodge also said many of Pimco’s large clients, including Calpers, are sticking with the firm and that the new investment team led by Daniel Ivascyn has removed a lot of “uncertainty” for clients.

In a blog post, Brian Berglund, an ERISA attorney and partner at Bryan Cave, noted that PIMCOs Total Return Fund, previously managed by Gross, is a “pillar” of many 401(k) investment platforms.

“One thing is certain,” wrote Berglund, “Gross’ departure from PIMCO means that many 401(k) plan fiduciaries are, or soon will be, discerning how to react.”

Berglund suggested sponsors use the occasion to revisit core procedural prudence best practices.

Specifically, sponsors need to make sure their Investment Policy Statement is current, he said, particularly if investment managers and advisors are placing particular funds on a watch list.

He said that the larger sponsors his firm works with almost uniformly have an IPS in place.

“If the plan’s IPS contains a procedure for monitoring managers or placing them on a watch list, as most do, then the plan fiduciaries should follow such policy and document those actions,” said Berglund.

Only one thing exposes fiduciaries to more liability than not having an IPS in place, he said.

And that would be not being in compliance with their own best practices.

“That we’ve learned in litigation,” Berglund said.

Outflows at PIMCO and Janus have been sizeable for some time.

According to Morningstar, Denver-based Janus had outflows of $5.3 billion in the first eight months of the year, while outflows at PIMCO totaled $34.5 billion through Aug. 31.

Under Gross’ leadership, Janus’ fixed-income operations could grow to $65 billion to $70 billion from $31 billion, according to Craig Siegenthaler at Credit Suisse. He also wrote that Gross may “significantly improve” the fund group’s organic growth rate through higher bond inflows.

Morningstar ranked PIMCO as the fifth-largest fund group based on assets of $519 billion as of Aug. 31, while Janus came in 22nd with $102 billion.

On Monday, St. James’s Place Plc, a U.K. wealth firm that manages $80 billion, announced it was removing PIMCO’s mandate to run its Multi Asset fund. The decision was made before last week’s news.

The change will allow for “the potential for strong returns and greater capital protection over the medium term” and “a reduction in the external management charge,” Chris Ralph, chief investment officer of St. James’s Place, said in the statement.

Bloomberg News and ThinkAdvisor contribute to this report.