Costco seared consumer claims made in a lawsuit about alleged preservatives in its popular $5 rotisserie chicken, according to a recent legal filing.

Two Costco customers in California argued in a proposed class action complaint filed in January that the Kirkland Signature Seasoned Rotisserie Chicken contains preservatives carrageenan and sodium phosphate, despite company advertising that claims the opposite.

But Charles Sipos, the attorney representing the Issaquah-based warehouse club, called the plaintiffs’ argument about false advertising “fatally flawed” because carrageenan and sodium phosphate are not categorized as preservatives by the U.S. Food and Drug Administration’s regulations. Instead, he said they’re listed as ingredients that are part of the roasted bird’s seasoning.

Carrageenan is an additive made of seaweed that thickens and preserves processed foods. Sodium phosphate is another additive in processed foods, used for thickening, curing, leavening and emulsifying.

Costco is asking the U.S. District Court for the Southern District of California to dismiss the complaint, according to the motion filed Thursday.

Sipos didn’t immediately respond to a request for comment.

In the proposed class action lawsuit, attorneys representing the shoppers claim that Costco violated Washington’s Consumer Protection Act and California’s Consumers Legal Remedies Act, along with other California statutes.

They’re pressing Costco to stop marketing the chicken as free of preservatives and for customers in the U.S. who have purchased the product to join in a class-action lawsuit. The attorneys are also seeking monetary damages.

The Almeida Law Group, which is representing the California plaintiffs, didn’t immediately respond to a request for comment.

Sipos said the lawsuit fails to pinpoint any clear injury in the proposed class action.

“They allege that Costco’s ‘No Preservatives’ statement enabled the company

to charge more for Rotisserie Chicken,” he wrote in the motion.

“Yet, the Amended Complaint does not identify a single ‘competitor’ who prices a whole rotisserie chicken for sale for less than $4.99.”

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