LOS ANGELES — A group of California homeowners is taking on insurance companies that they say illegally coordinated to deny coverage to fire-prone areas, leaving thousands of displaced residents drastically underinsured as they fight for funding to rebuild.

The homeowners, many of whom were affected by the recent wildfires that torched large swaths of Los Angeles, have filed a lawsuit alleging that California insurance companies colluded in a “nefarious conspiracy” to shut out high-risk homeowners from the insurance market.

The complaint, filed Friday in Los Angeles County, accuses dozens of major insurance companies and their subsidiaries of collaborating in a “group boycott” of certain areas to eliminate competition and force homeowners toward the state’s insurer of last resort, a program known as the California FAIR Plan.

The lawsuits name California’s largest home insurers, including State Farm, Farmers, Berkshire Hathaway, Allstate and Liberty Mutual. None of them have provided a comment on the allegations.

The FAIR Plan has its own reserves and is intended to provide basic insurance to residents who cannot find a policy through the private marketplace. While it was created by the governor and the Legislature, and the state’s insurance commissioner has oversight, it is not a public program. The insurance companies named in the lawsuit jointly own and operate the FAIR plan, offering terms that limit their risk and place a higher burden on policyholders.

“They knew that they could force people, by dropping insurance, into that plan which had higher premiums and far lower coverages,” Robert Ruyak, an attorney with Larson LLP, the law firm that brought the complaint, said. “They realized that they could take this device, which is to protect consumers, and turn it into something that protected them.”

Ruyak argues the insurance companies knew they could limit their liability by directing policyholders onto the FAIR Plan, which allows companies to recoup up to half of their losses through premium increases, by agreeing that no company would insure high-risk areas.

“All of these insurance companies participate in the California FAIR Plan. They own it and manage it. It is not a California entity, it is not even a separate entity … the only way this scheme would work is if no one would pick up a dropped policy at any price, on any terms. And that’s what happened.”

Millions of U.S. homeowners have in recent years struggled to buy property insurance as companies have increasingly declined to offer coverage to people who live in high-risk areas, particularly as climate change has supercharged some natural disasters. An NBC News analysis in 2023 found that a quarter of all U.S. homes may be at risk of a climate-induced insurance shock.

California has been among the hardest hit by what some have called an “insurance crisis.” The state’s FAIR Plan, meanwhile, has been the subject of growing scrutiny and frustration from insurance regulators and customers.

The plaintiffs are asking for a jury trial and seeking payment for three times their damages. 

A separate class-action lawsuit filed Friday makes similar allegations.