Don Julio Lawsuit: Claims, Products Named, and How to Join

The Don Julio lawsuit is a set of proposed class actions accusing Diageo North America of falsely marketing Don Julio tequila as “100% Blue Weber Agave” when, according to laboratory testing cited by the plaintiffs, the bottles allegedly contain significant amounts of alcohol made from sugarcane or corn. Cases have been filed in New York, Florida, California, and Quebec. Diageo denies the allegations and has moved to dismiss. As of mid-2026, no court has ruled on the merits, no class has been certified, and there is no settlement or claims process to join.1Hagens Berman. Casamigos Don Julio Tequila

What the Lawsuit Claims

The core allegation is simple. Don Julio is sold at a premium price on the promise that it is made exclusively from Blue Weber agave, as both U.S. and Mexican law require for anything labeled “100% agave.”2Consejo Regulador del Tequila. Our Tequila The plaintiffs say independent testing shows that isn’t true, and that consumers paid more than they would have if the labels reflected what was actually in the bottle.1Hagens Berman. Casamigos Don Julio Tequila

The evidence they rely on is carbon isotope ratio analysis, which the complaints say can distinguish alcohol fermented from agave (a CAM plant) from alcohol fermented from C4 plants like sugarcane and corn.3Mezcalistas. Tequila Lawsuit Lab Tests4KTLA. Casamigos Don Julio Lawsuits5Mezcalistas. Casamigos Lawsuit If those numbers are accurate, the majority of the alcohol in those bottles would come from something other than agave.

The California filing goes further than the others, alleging violations of the federal Racketeer Influenced and Corrupt Organizations Act (RICO). It accuses Diageo, its Mexican subsidiary, and the Consejo Regulador del Tequila (CRT, the Mexican body that certifies tequila) of operating what plaintiffs call an “Adulterated Tequila Enterprise” involving mail fraud, wire fraud, and false advertising. The complaints allege the CRT has a conflict of interest because its board includes representatives from the producers it regulates, including a Diageo subsidiary.6KQED. Diageo Class Action Complaint

Which Don Julio Products Are Named

The New York complaint specifically names Don Julio 1942.7BevLaw. Diageo Suit Complaint The California filing covers a much broader list: Don Julio Blanco, Reposado, Añejo, 70 Cristalino, Alma Miel, Rosado, Ultima Reserva, and Primavera.6KQED. Diageo Class Action Complaint The Quebec filing similarly names a broad range of Don Julio variants.8Lambert Avocats. Class Action Diageo Casamigos, also owned by Diageo, is a defendant in the same cases.

Where the Cases Have Been Filed

Four separate actions were on file as of mid-2026:

How Diageo Is Responding

Diageo has denied every allegation and moved to dismiss in both the New York and Florida cases in late October and early November 2025.12The Drinks Business. Diageo Moves to Dismiss Implausible 100% Agave Tequila Lawsuit A company spokesperson said: “We are confident in our defence as all bottled Casamigos and Don Julio tequilas labelled as ‘100% agave’ are just that — proudly made from 100% blue weber agave.”13Drinks Intel. Diageo Seeks Dismissal of Casamigos Don Julio Tequila US Class Action

The company’s legal arguments run on two tracks. On the science, Diageo calls the isotope testing “scientifically unvalidated” and says it was performed by a single European laboratory on a handful of samples, none of which the plaintiffs themselves purchased. In its New York motion, Diageo described the evidence as “partial and unintelligible results from five unidentified samples” extrapolated to more than 73 bottles named in the complaint.14The Spirits Business. Diageo Doubles Down on Defence of 100% Agave Tequilas Its Florida filing compared the plaintiffs’ testing theory to “the equivalent of someone claiming the earth is flat because he saw a ‘test’ result somewhere that says his neighbour’s backyard is level.”15The Drinks Business. Diageo Rejects Flat Earth Tequila Purity Claims

On the regulatory side, Diageo says its tequilas undergo “multiple layers of verification,” are certified annually by the CRT, and carry labels approved by the U.S. Alcohol and Tobacco Tax and Trade Bureau. It called the Florida complaint “copycat conjecture” filed only after those plaintiffs learned of the New York suit.11The Spirits Business. Diageo Moves to Dismiss Tequila Class Action

The Science the Case Turns On

Whether the case survives will depend heavily on the reliability of carbon isotope testing. Peer-reviewed research supports the general principle that isotope values can confirm the sugar source in tequila, and Thermo Fisher Scientific has described GC-IRMS (Gas Chromatography Isotope Ratio Mass Spectrometry) as a “reliable method” for detecting beverage adulteration.16PMC. Stable Isotope Analysis of Tequila17Thermo Fisher Scientific. GC-IRMS Carbon Oxygen Tequila Application Note

The same peer-reviewed study also noted that isotope analysis works best as an “additional parameter” and has limitations. One paper cited in the complaint itself acknowledged that certain isotope techniques, including SNIF-NMR, are “not reliable” in some circumstances because chemical manipulation of ethanol can let adulterated beverages pass as legitimate.16PMC. Stable Isotope Analysis of Tequila Those limitations are the core of Diageo’s motion to dismiss.

Current Status and How To Join

The litigation is still in its early stages. In the lead New York case, Diageo’s October 31, 2025 motion to dismiss remains pending, with a status conference set for June 17, 2026.18PACER Monitor. Pusateri et al v. Diageo North America, Inc. In May 2026, Diageo asked the court to stay the proceedings while the motions are decided, and the plaintiffs opposed the request.1Hagens Berman. Casamigos Don Julio Tequila

There is no settlement in any of the cases. No class has been formally certified. No claims process exists, no administrator has been appointed, and no deadlines have been set for consumers to file anything.1Hagens Berman. Casamigos Don Julio Tequila

If you bought Don Julio in the United States and want to be kept informed, Hagens Berman, one of the firms leading the New York case, accepts contact through an online form. The firm says class members are never asked to pay out-of-pocket costs, and any attorney fees would be set by the court if a settlement is reached.1Hagens Berman. Casamigos Don Julio Tequila In Quebec, residents who bought the named products since May 20, 2022 are automatically part of the proposed class if authorization is granted; no sign-up is needed.8Lambert Avocats. Class Action Diageo Anywhere else, there is nothing yet to join.