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In re Zimmer M/L Taper Hip Prosthesis (McMillian v. Zimmer US, Inc.)

U.S. District Court, Southern District of New York · S.D.N.Y. · New York bar guidance

Court sanction

Verified April 26, 2026

Citation
In re Zimmer M/L Taper Hip Prosthesis Prods. Liab. Litig., No. 18-MD-2859 (JMF) (S.D.N.Y. Dec. 16, 2025) (Furman, J.) (relating to McMillian v. Zimmer US, Inc., No. 20-CV-2358)
Decided
December 16, 2025

Summary

In the Zimmer M/L Taper Hip Prosthesis multidistrict litigation (18-MD-2859), Judge Jesse M. Furman ordered sanctions against plaintiff's counsel in the member case McMillian v. Zimmer US, Inc., 20-CV-2358, after counsel conceded that papers filed on December 4, 2025 (ECF Nos. 100 through 103, opposing defendants' summary judgment and Daubert motions) contained AI-generated hallucinations and inaccuracies. The order required plaintiff to file corrected versions with redlines by December 22, 2025, and directed defendants to file revised reply briefs by January 14, 2026.

AI tool:
Unspecified generative AI
Sanction amount:
$9,000
This case summary is informational only. Verify the underlying opinion or order against the primary source before relying on it in any filing or client matter.

What sanction did the court impose?

Plaintiff's counsel ordered to reimburse defendants for fees and costs incurred as a result of the defective filings, with the parties first directed to confer on the amount and, absent agreement, defendants to submit a fee letter supported by contemporaneous billing records by January 21, 2026. Reporting indicates the resulting fee award totaled approximately $9,000, though the December 16, 2025 order itself does not fix a sum.

Why does In re Zimmer M/L Taper Hip Prosthesis (McMillian v. Zimmer US, Inc.) matter for law firms using AI?

McMillian is the relatively rare MDL-context AI-hallucination sanction, and the procedural posture is instructive: the defective filings were the plaintiff’s opposition to summary judgment and Daubert motions, meaning the hallucinated authority went to dispositive issues rather than a routine motion. For a managing partner, the order’s structure also illustrates a now-common judicial reflex, fee-shifting calibrated to the actual cost imposed on the opposing party rather than a flat penalty, with the amount fixed only after the parties confer on contemporaneous billing.

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.

Unverified claims:
  • The $9,000 monetary figure is from the Charlotin candidate row and presumably reflects the post-conferral fee award; the December 16, 2025 order itself sets a fee-shifting framework but does not state a dollar amount. The follow-on order quantifying fees was not retrieved.
  • The specific generative AI tool used by plaintiff's counsel is not identified in the order.