Mitra Mirage v. Costco Wholesale Corporation

What did the court warn about?

Judge Anne Hwang denied the motion to remand, holding that Costco is incorporated and has its principal place of business in Washington, that the plaintiff is a California resident, and that the "minimum contacts" analysis the plaintiff relied on governs personal jurisdiction, not citizenship for diversity purposes. On the citation, the court stated: "Plaintiff is admonished that any future citations to authority that do not appear to exist will result in the Court setting an order to show cause re why sanctions should not be imposed." The order imposes no sanction, requires no response or declaration, and makes no referral; the admonishment is the only consequence. The court also declined to rule on Costco's objections to the plaintiff's exhibits because it did not rely on them.

Why does Mitra Mirage v. Costco Wholesale Corporation matter for law firms using AI?

Mirage is a short admonishment inside a routine remand ruling. Costco removed a slip-and-fall case on diversity grounds, and the plaintiff’s motion to remand rested in part on a personal-jurisdiction theory that, the court explained, does not determine citizenship. At the end of its discussion, Judge Hwang noted that the motion and reply cited a case “purported to be Martinez v. Ford Motor Co.” that the court could not find.

The court connected the citation to its own standing order rather than making a finding about how the citation arose. It wrote that “[t]o the extent that Plaintiff has relied on artificial intelligence,” the plaintiff had not complied with the standing order’s requirement of a separate declaration disclosing AI use and certifying that the filer reviewed the sources and verified the content. The order does not say AI was used.

The consequence was a warning: future citations to authority that does not appear to exist will lead to an order to show cause re sanctions. Firms documenting compliance may wish to consider that, here, the judge’s AI disclosure standing order supplied the framework the court used, so a filing that relied on AI without the required declaration would have been out of compliance independently of the citation itself. The judge’s standing order was reissued on September 25, 2026 without the declaration requirement.