Nov 14, 2025 3:31 PM Eastern Standard Time Hagens Berman: Consumers Sue Costco Alleging Kirkland Signature Tequila is a Sham Share Retail giant accused of knowingly selling adulterated tequila containing "significant presence of non-agave sugars†SEATTLE--(BUSINESS WIRE)--Costco is in the crosshairs of a new class-action lawsuit filed by Seattle-based consumer-rights law firm Hagens Berman, accusing the retailer of knowingly selling adulterated tequila that contains "significant presence of non-agave sugar ...