The federal judge overseeing a mountain of military earplug litigation against 3M has ordered the company and plaintiffs to reacommence settlement talks.

The ruling comes after 3M failed last week to move resolution of more than 220,000 military earplug cases from a U.S. District Court in Florida to a bankruptcy court. Plaintiffs — all active or retired military members — claim the earplugs were defective, causing hearing damage.

Within 30 days, attorneys for 3M and plaintiffs must attend a multi-day mediation session held by a court-appointed special master, said a Tuesday order from Casey Rodgers, the U.S. District Court judge in northern Florida presiding over the military earplug lawsuits.

The time "could not be riper" for a mediated settlement, Rodgers wrote. "This is in everyone's best interests."

Both parties must operate in "good faith," she added.

Rodgers had ordered a mediation session in mid-July, but it went nowhere. In late July — after 3M tried initiated its bankruptcy court gambit— Rodgers said she would look into whether 3M "proceeded in good faith" during the earlier mediation.

Maplewood-based 3M put its Aearo Technologies subsidiary into Chapter 11 bankruptcy protection, automatically freezing litigation against Aearo. The subsidiary is also named as a defendant in the earplug suits against 3M.

Aearo asked the U.S. Bankruptcy Court in Indianapolis to extend the litigation freeze — or "automatic stay" — to 3M itself, a controversial move. Settling the earplug cases in bankruptcy court would likely be less costly for 3M, and would avoid thousands of jury trials in federal court.

But on Friday, U.S. Bankruptcy Court Judge Jeffrey Graham in the Southern District of Indiana declined to extend the litigation freeze to 3M. That decision will be appealed, but for now the next move for the lawsuits is back in Rodgers' court.

And after "significant developments" in the earplug case over the past month, "both sides are now highly motivated and committed" to reaching a settlement, Rodgers wrote Tuesday.

The wave of lawsuits against 3M came after the company in 2018 settled a government whistleblower suit regarding the earplugs. It claimed Aearo, which 3M bought in 2007, knew about "dangerous design defects" in its earplugs in 2000.

The military earplug suits were roped together in a "multi-district litigation" — or MDL — case presided over by Rodgers. MDLs are used in the federal court system for complex product liability matters with many separate claims.

The earplug litigation is the largest MDL ever; 3M has said it is "broken beyond repair."

MDLs commonly feature bellwether trials that are supposed to set a tone for settling all claims. Plaintiffs won 10 of 16 earplug bellwether cases against 3M; juries awarded them nearly $300 million.

Stock analysts have estimated 3M's total earplug liabilities could be in the tens of billions of dollars.