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Incident Tracker / United States (state)

Kleyman Law Group, P.C. v. Kaloidis, Index No. 502644/2025 (N.Y. Sup. Ct., Kings County)

·Supreme Court of the State of New York, Kings County·US-STATESanctions

In a fee suit against a client's estate, the Supreme Court of New York, Kings County, found that plaintiff-lawyer Alex Kleyman had cited 23 nonexistent decisions and misrepresented 83 real ones across 19 filings drafted with Claude and other AI tools. After a sanctions hearing the court imposed about USD 46,500 and referred him to the grievance committee.

Court
Supreme Court of the State of New York, Kings County
Date
2026-08-04
Who used the AI
Lawyer
AI tool
Claude and other generative AI platforms (per hearing testimony)
Conduct
Attorney Alex I. Kleyman, suing a former client's estate for about USD 1.246 million in fees, filed 19 submissions containing 23 fictitious decisions, fabricated quotations and materially misstated holdings of at least 83 real decisions, and did not verify them even after opposing counsel challenged them.
Outcome
Sanctions
Penalty
US$46,511
Regulatory outcome
Attorney Grievance Committee (New York): The order refers Alex I. Kleyman to the State of New York Grievance Committee for the Second, Eleventh and Thirteenth Judicial Districts, the court finding a substantial likelihood of substantial violations of the Rules of Professional Conduct. The USD 46,511 comprises a USD 10,000 sanction payable to the Lawyers' Fund for Client Protection and USD 36,511.35 in attorneys' fees and costs (order read 3 Sep 2026). No Grievance Committee disposition on record. (2026-08-04)
Status
Verified against listed sources
Last checked
2026-09-03

What was fabricated or misused

  • twenty-three fictitious decisions cited on forty-seven occasions; Appendix A listing them was not available in the fetched order
  • holdings in at least eighty-three genuine decisions materially misstated across nineteen submissions
  • fabricated citations and misquoted citations in submissions prepared from April 2025 to December 2025 using Claude and other GenAI platforms

What the court said

“Cumulatively, Kleyman cited twenty-three fictitious decisions and misrepresented the holdings in at least eighty-three genuine decisions across those nineteen separate submissions.”
Supreme Court of the State of New York, Kings County, 2026 WL 2324499, *1
“He conceded that he could have attempted to verify the cited decisions through a free Internet search engine or research service and did not do so.”
Supreme Court of the State of New York, Kings County, 2026 WL 2324499, *1
“After defense counsel brought the issue to light in their cross-motion, Kleyman returned to the same AI platform that had generated the citations and relied on its assurance that the authorities were valid.”
Supreme Court of the State of New York, Kings County, 2026 WL 2324499, *5
“The Court therefore concludes that referral to the AGC is required.”
Supreme Court of the State of New York, Kings County, 2026 WL 2324499, *6

Timeline

  1. Kleyman Law Group commenced the fee action.
  2. Defendant raised the false-authority issue in an affirmation.
  3. Court found frivolous conduct and set a sanctions hearing.
  4. Court held the sanctions hearing.
  5. Court imposed $10,000, fee shifting of $36,511.35 and AGC referral.

Why this case matters

Kleyman extends the New York sequence from Mata v Avianca and Deutsche Bank v LeTennier. The volume was larger than most records: nineteen submissions, twenty-three fictitious decisions, forty-seven uses, and at least eighty-three misstated real decisions. The order also involved a lawyer litigating for his own firm, so the court did not weigh a separate client harmed by counsel's AI use. Even so, it imposed the maximum single-occurrence sanction, full fee shifting and AGC referral because the false material continued after notice.

Practice note

When opposing counsel flags a citation, stop using AI to verify AI output. Open the cited case in Lexis, Westlaw, a free court database, or another primary source and compare the holding to the proposition in the filing. Do that for every affected submission before filing another paper, and tell the court what was checked.

Primary sources for this incident

Related regulation records for this incident

No related regulation record has been linked to this incident yet.

Similar incidents on the record

Cite this record

SafeLegalAI Global Legal AI Incident Tracker, “Kleyman Law Group, P.C. v. Kaloidis, Index No. 502644/2025 (N.Y. Sup. Ct., Kings County)”, safelegalai.com/tracker/kleyman-law-group-v-kaloidis (accessed 2026-10-07). Data: CC BY 4.0.

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