Chenco Engineering & Consulting GmbH v. Do-Fluoride New Materials Co. Ltd.
U.S. District Court, District of Idaho · D. Idaho · Idaho bar guidance
Verified May 5, 2026
- Citation
- Chenco Eng'g & Consulting GmbH v. Do-Fluoride New Materials Co. Ltd., No. 2:24-cv-00632-AKB, 2025 WL 2430556 (D. Idaho Aug. 22, 2025) (Brailsford, J.)
- Decided
- August 22, 2025
Summary
Defendant Do-Fluoride New Materials, opposing Chenco's motion to remand, moved for leave to file a surreply purporting to address "legal misstatements and omissions" in plaintiff's reply. Judge Amanda K. Brailsford reviewed the surreply brief and identified at least five purported direct quotations that did not appear anywhere in the cited cases, including fabricated quotes attributed to Jones Day v. Orrick, Herrington & Sutcliffe LLP, 42 F.4th 1131 (9th Cir. 2022), C.B.F. Industria de Gusa S/A v. AMCI Holdings, Inc., 850 F.3d 58 (2d Cir. 2017), National Aluminum Co. v. Peak Chemical Corp., 132 F. Supp. 3d 990 (N.D. Ill. 2015), and Infuturia Global Ltd. v. Sequus Pharmaceuticals, Inc., 631 F.3d 1133 (9th Cir. 2011), plus a citation to Int'l Trading & Indus. Inv. Co. v. DynCorp Aerospace Tech. for a proposition the case did not address. The court noted the irony that New Materials had "freely accused opposing counsel of misstating the law" while submitting non-existent quotes of its own.
- AI tool:
- Unspecified generative AI
What sanction did the court impose?
The court denied New Materials' motion for leave to file the surreply (Dkt. 34) and reminded counsel of their duties under Idaho Rule of Professional Conduct 3.3, citing United States v. Hayes (E.D. Cal. 2025) and Grant v. City of Long Beach (9th Cir. 2024) as cautionary precedent. No monetary sanction was imposed in this order. The court separately granted Chenco's motion to remand to Idaho state court.
Why does Chenco Engineering & Consulting GmbH v. Do-Fluoride New Materials Co. Ltd. matter for law firms using AI?
Chenco illustrates a softer judicial response to fabricated authority: the court caught five non-existent direct quotations in a surreply brief, denied the motion, and admonished counsel under Rule 3.3, but stopped short of monetary sanctions or a show-cause order. For a managing partner, the lesson is that judges in 2025 are now actively spot-checking quoted language against the underlying opinions, and that accusing opposing counsel of misstating the law while filing fabricated quotes is a particularly poor posture, here memorialized in a published opinion now indexed on Westlaw.
Sources
Primary sources
Further reading
Source PDF is a Westlaw printout mirrored from the Damien Charlotin hallucination database. We are working to add the underlying court docket (PACER, CourtListener, or court website) as a second source.
- The order does not name the AI tool used. The court invoked Hayes (which "suspected" AI) as cautionary authority, indicating an inference rather than an admission of AI use by counsel.
- No CourtListener docket URL was confirmed during verification; the Charlotin S3 mirror of the order is the cited source.