WASHINGTON (Reuters) -The state of California announced a lawsuit against three major plastic bag producers and reached a settlement with four other manufacturers on Friday after concluding an investigation into their false claims that these bags were recyclable.

California Attorney General Rob Bonta announced a lawsuit against Novolex Holdings LLC, Inteplast Group Corp, and Mettler Packaging LLC alleging violations of California's Environmental Marketing Claims Act, False Advertising Law, and Unfair Competition Law.    

Bonta also announced a settlement with four plastic bag producers, Revolution Sustainable Solutions LLC (Revolution), Metro Poly Corp. (Metro Poly), PreZero US Packaging LLC (PreZero), and Advance Polybag, Inc. (API), resolving their alleged violations of those same laws.

"The consequences of these violations are severe: Billions of plastic carryout bags end up in landfills, incinerators, and the environment instead of being recycled as the bags proclaim. Our legal actions today make it clear: No corporation is above the law," Bonta said in a statement.

The actions come nearly three years after Bonta launched an investigation into plastic bag producers in which he requested they substantiate claims that their bags are recyclable.

That investigation came after the California Statewide Commission on Recycling Markets and Curbside Recycling had asked the attorney general and regulator CalRecycle to crack down on what it claimed was illegal labeling that was undermining the state's efforts to tackle plastic pollution.

The sale of these thicker recycled plastic bags emerged from what critics said became a loophole in California's 2017 ban on single-use shopping bags that enabled retailers to sell reusable plastic bags for a minimum of 10 cents each if the bags can be recycled in California.

As part of the settlement, the four companies agreed to halt plastic bag sales in California and pay a total of $1.8 million to the state.