In what is only the latest outrageous ruling by a California judge so far this year, Starbucks and a handful of other coffee chains lost a yearslong legal battle against a consumer advocacy group trying to force coffee companies to attach cancer warnings to their packaging, according to Reuters.

The Council for Education and Research on Toxics (CERT) sued 90 coffee retailers on the grounds they were in violation of a state law requiring companies to warn consumers about potentially cancerous chemicals in their products. Several defendants settled before the final decision and agreed to post the signage and pay millions in fines.

A chemical called acrylamide, which is one of the byproducts of roasting coffee beans, is present in brewed coffee and is listed as a potential carcinogen. CERT's lawsuit was filed back in 2010.

Per Reuters, Los Angeles Superior Court Judge Elihu Berle ruled in a decision dated Wednesday that the defendants in the lawsuit had failed to prove that coffee isn't a carcinogen.

Of course, Starbucks' lawyers aren't the only ones having difficulty proving this.

Research shows that coffee can lower the incidence of diabetes and liver disease - and even prolong life. The World Health Organization removed coffee from its "possible carcinogen" list in 2016.

One professional researcher contacted by CBS said there's not enough evidence, in his opinion, to warrant such a warning label on coffee. Coffee companies have said removing acrylamide from brewed coffee would make it implausibly expensive and difficult to prepare in stores.

Others have said that if the potato chip industry was able to remove acrylamide from its product (which it did after being sued by CERT), Big Coffee could also accomplish it.

But regardless of whether a warning is truly warranted, many California coffee shops already hang warnings advising customers about the dangers of acrylamide.

But what's worse for companies like Starbucks is that if the industry loses the inevitable appeal (companies have already said they're "considering it"), the judge could impose a stiff civil penalty. By law, it could be as high as $2,500 per person exposed and per incident over the span of eight years. That could be an astronomical figure in California, the most populous state in the US, with 40 million residents.

If the ruling does stand, coffee companies might decide it's easier and cheaper to print warnings on all of their packaging - rather than producing separate packaging just for California.

So once again, the impact of a California judge's ruling will be felt across the entire country.