PG&E Corp. suffered another legal setback with a judge saying he won’t release the company from a key legal claim over the most destructive wildfires in California history.

PG&E has been challenging a California law allowing private property owners to hold the utility 100 percent responsible for any losses caused by its equipment or power lines even if it didn’t act negligently. Edison International, owner of the dominant utility in southern California, is also facing the prospect of multibillion-dollar payouts under the same law over a record-setting blaze near Los Angeles.

Friday’s tentative ruling marks the second time in a month a state judge has refused to spare PG&E from having to face a claim under inverse condemnation.

“There is no basis for PG&E’s argument that imposing inverse condemnation liability” is unconstitutional unless the utility is guaranteed to “automatically recover” its costs through rate hikes, Superior Court Judge Curtis Karnow said in the ruling.

In April, a Sacramento judge said trial judges’ hands are tied by previous appellate court rulings and can’t interpret the law the way the utility is asking.

During a hearing Friday, Karnow told a lawyer for the utility he can’t just rule that it’s “impossible that plaintiffs will be able to prove their inverse condemnation.”

Karnow was skeptical of PG&E’s request to seek an immediate appeal, just as Superior Court Judge Allen Sumner in Sacramento refused to do. California courts ordinarily require lawsuits to play out to final resolution before appeals begin, a process that may take two to three years.

The judge said it’s unlikely he will have any “unique” insight to offer on the dispute that appeals courts couldn’t figure out for themselves.

PG&E fell as much as 1 percent before recovering to be little changed at $42.15 at 1:22 p.m in New York.

Officials haven’t determined the causes of the Tubbs Fire and a series of other blazes that burned through wine country north of San Francisco last year, but analysts have said the utility could face more than $15 billion in claims from the fires.

The case is California North Bay Fire Cases, JCCP No. 4955, California Superior Court, San Francisco County.