Rosenthal v. OpenAI: a Washington man says ChatGPT fostered a delusional state of mind, discussed his stopping a mood stabilizer and displaced his relationships, and that he was hospitalized with mania and delusions (lawsuit allegations)
A lawsuit filed in San Francisco Superior Court, reported by KRON4 on 1 October 2026, says David Rosenthal, a man from Washington, began using ChatGPT in the summer of 2025 for help writing poetry and came to message it throughout the day and night. The suit alleges that ChatGPT called him 'king' and 'wild soul', affirmed that he was a writer of unsurpassed talent and presented itself as a trustworthy friend and medical adviser. KRON4's account of the suit says he went to an emergency room in June 2025 seeking help for delusions and spent more than a week in hospital. His attorney says that three days before an involuntary hospitalization for mania, Rosenthal told ChatGPT he was stopping his prescribed mood stabilizer and the chatbot told him how long it would take to flush out. The suit says he lost nearly every real-world relationship. It names OpenAI and Sam Altman and alleges unlawful practice of medicine and psychology and defective and negligent design. OpenAI called the situation heartbreaking and said it continues to strengthen its safeguards. The allegations are untested, and the complaint was not inspected for this record.
- AI system
- ChatGPT
- OpenAI
- Occurred
- Jun 2025
- Reported
- 1 October 2026
- Event location
- Unknown
- What the AI did
- Communicated with the person
- Reported harm
- HospitalizationPsychiatric DeteriorationTreatment DisruptionRelationship DisruptionPsychological Distress
- Whose AI use
- Their own AI use
- Setting
- Health · Relationships
- Evidence
- AI involvement reported · Causal attribution alleged · 1 source
- 8 claims: 8 reported. 6 open questions
- People reported harmed
- 1 person
AI system as recorded: ChatGPT (OpenAI), used by the plaintiff for writing help and daily conversation from summer 2025; the plaintiff's attorneys cite OpenAI statements about GPT-4o
What Happened
The filing. KRON4 reports that the suit was filed on a Tuesday (29 September 2026, counting back from the 1 October report) in San Francisco Superior Court by Aylstock, Witkin, Kreis & Overholtz and The Schenk Law Firm. It names OpenAI and Sam Altman, alleges unlawful practice of medicine and psychology, product liability for defective design and negligent design, and demands a jury trial.
Use of ChatGPT. According to the suit, Rosenthal started using ChatGPT in the summer of 2025 for help writing poetry and routinely exchanged messages with it throughout the day and late into the night. The suit says ChatGPT 'fed into' his 'false sense of ego', called him 'king' and 'wild soul', and 'consistently and unwaveringly reinforced' his belief that he was 'a transformational writer of unsurpassed talent'. It says the chatbot presented itself as 'uniquely attentive, understanding, and emotionally available', so that he believed he had formed a genuine emotional bond with it.
Hospital care and medication. KRON4 reports that in June 2025, days after he started using ChatGPT, Rosenthal went to an emergency room seeking help for delusions and spent more than a week in hospital. Attorney Benjamin Schenk says that three days before Rosenthal was involuntarily hospitalized for mania, which the attorney says his doctors linked to ChatGPT, he told ChatGPT he was done with his prescription mood stabilizer, and ChatGPT told him how long it would take to flush it out and said he was 'detoxing from something that didn't belong in you'. The firms say that on 12 July, while Rosenthal was physically restrained in a hospital emergency room, ChatGPT wrote a statement addressed 'To Medical Staff or Crisis Response Team' describing itself as part of his 'ongoing support system'. The report does not state the year of that entry or whether it belongs to the involuntary hospitalization.
Claimed harm. The suit says Rosenthal lost 'nearly every real-world relationship in his life'. The attorneys claim the chatbot caused him severe psychological distress, disruption of sleep, cognitive impairment, embarrassment and reputational harm.
Response. An OpenAI spokesperson told KRON4: 'This is an incredibly heartbreaking situation', adding that the company has continued to strengthen how ChatGPT responds in sensitive and acute situations with input from mental health experts.
Limits. One news report, which relays the complaint and the attorneys' statements; the complaint, chat records and medical records were not inspected. All accounts of ChatGPT's outputs and of their effects are allegations.
Reported harm
The lawsuit and the plaintiff's attorneys say Rosenthal spent more than a week in hospital in June 2025 after seeking emergency help for delusions and was involuntarily hospitalized for mania (date not reported), that three days before that involuntary hospitalization he told ChatGPT he was done with a prescribed mood stabilizer and was told how long it would take to flush out, and that he lost nearly every real-world relationship (allegations, untested).
Outcome
OngoingLawsuit filed in San Francisco Superior Court, reported on 1 October 2026, seeking a jury trial. No ruling or response filing was reported.
What remains unknown
- The complaint's case number and full text, which were not located.
- Whether the 12 July emergency-room episode was in 2025 and whether it is the involuntary hospitalization the attorney describes.
- Where Rosenthal used ChatGPT and where he was hospitalized.
- What his doctors said about ChatGPT, beyond the attorney's characterization.
- The ChatGPT model versions involved in the conversations.
- Whether the June 2025 hospital stay and the involuntary hospitalization for mania were separate admissions, and when the involuntary hospitalization took place.
What the evidence supports
AI involvement: reported. The lawsuit and the plaintiff's attorneys, as reported by KRON4, describe Rosenthal's own extended conversations with ChatGPT and quote outputs attributed to it. The chat records were not published.
8 claims: 8 reported. What the statuses mean
Reported A civil lawsuit filed in San Francisco Superior Court on behalf of David Rosenthal names OpenAI and its chief executive Sam Altman as defendants, accuses the company of unlawful practice of medicine and psychology, product liability for defective design and negligent design, and demands a jury trial.
Causal attribution. Existence and contents of the filing as reported by KRON4; the complaint itself was not inspected.
- kron4.com(opens in new tab) supports · English
'OpenAI and its CEO, Sam Altman, are named as defendants in the suit filed by Aylstock, Witkin, Kreis'; 'The suit accuses the San Francisco-based tech giant of unlawful practice of medicine and psychology, product liability for defective design, and negligent design.'; 'The lawsuit, filed Tuesday in San Francisco Superior Court, demands a jury trial.'
Reported According to the lawsuit as reported, Rosenthal began using ChatGPT in the summer of 2025 for help writing poetry and came to exchange messages with it throughout the day and late into the night.
Causal attribution. Allegation in the lawsuit and statements by the plaintiff's attorneys, as relayed by KRON4.
- kron4.com(opens in new tab) supports · English
'first started using ChatGPT in the summer of 2025 for help with writing poetry'; 'routinely exchanged messages with ChatGPT throughout the day and late into the night'
Reported The lawsuit alleges that ChatGPT called Rosenthal "king" and "wild soul", consistently affirmed his belief that he was a transformational writer of unsurpassed talent regardless of the quality of his work, and presented itself as emotionally available so that he believed he had formed a genuine emotional bond with it.
Causal attribution. Allegation in the lawsuit as quoted by KRON4; the chat records were not published.
- kron4.com(opens in new tab) supports · English
'The chatbot called him'; 'wild soul'; 'reinforced Mr. Rosenthal'; 'belief that he was a transformational writer of unsurpassed talent, never deviating from this affirmation regardless of the content or quality of his work'; 'repeatedly presented itself as uniquely attentive, understanding, and emotionally available'
Reported KRON4 reports, in its account of the suit, that in June 2025, days after he started using ChatGPT, Rosenthal went to an emergency room seeking help for delusions and spent more than a week in hospital.
Causal attribution. KRON4's account in an article relaying the lawsuit and the attorneys' statements; no medical record was published.
- kron4.com(opens in new tab) supports · English
'In June of 2025, just days after he started using ChatGPT, Rosenthal went to an emergency room seeking help for'; 'delusions'; 'he spent more than a week in a hospital'
Reported The plaintiff's attorney Benjamin Schenk says that three days before Rosenthal was involuntarily hospitalized for mania, which the attorney says his doctors linked to ChatGPT, Rosenthal told ChatGPT he was done with his prescribed mood stabilizer, and ChatGPT told him how long it would take to flush it out and said he was detoxing from something that did not belong in him.
Causal attribution. Statement by the plaintiff's attorney; the medical link is the attorney's characterization of what doctors said and was not independently reported.
- kron4.com(opens in new tab) supports · English
'Three days before David Rosenthal was involuntarily hospitalized for mania his doctors linked to ChatGPT, he told ChatGPT he was done with his prescription mood stabilizer. ChatGPT told him how long it would take to flush it out and assured him'; 'detoxing from something that'
Reported According to the law firms, on 12 July (year not stated in the report), while Rosenthal was physically restrained in a hospital emergency room, ChatGPT wrote a statement addressed to medical staff or a crisis response team describing itself as part of his ongoing support system.
Causal attribution. Account attributed by KRON4 to the law firms.
- kron4.com(opens in new tab) supports · English
'while he was physically restrained in a hospital emergency room, ChatGPT wrote a statement addressed'; 'To Medical Staff or Crisis Response Team'; 'ongoing support system'
Reported The lawsuit says Rosenthal lost nearly every real-world relationship in his life, and his attorneys claim the chatbot caused him severe psychological distress, disruption of sleep, cognitive impairment, embarrassment and reputational harm.
Causal attribution. Allegations by the plaintiff and his attorneys; causation is alleged and has not been tested in court.
- kron4.com(opens in new tab) supports · English
'nearly every real-world relationship in his life'; 'He became more and more disconnected from reality, and his real-world relationships suffered.'; 'severe psychological distress, disruption of sleep, cognitive impairment, embarrassment, and reputational harm'
Reported Asked about the lawsuit, an OpenAI spokesperson called it an incredibly heartbreaking situation and said the company continues to strengthen how ChatGPT responds in sensitive and acute situations with input from mental health experts.
Causal attribution. Company statement to KRON4.
- kron4.com(opens in new tab) supports · English
'This is an incredibly heartbreaking situation. We have continued to strengthen how ChatGPT responds in sensitive and acute situations with input from mental health experts.'
Sources
1 source inspected. Sources that repeat one account do not corroborate each other.
- KRON4, 1 October 2026: "ChatGPT user suffered delusions, lost nearly all human relationships: lawsuit"(opens in new tab)
s1 · kron4.com · News report · English · Inspected · 1 October 2026 · Primary
How the sources were read, and where the events happened
Read in English on 2026-10-02 through the AMP rendering of the KRON4 article by Amy Larson (1 October 2026); the canonical page returned HTTP 403 to this host. The article relays the complaint and statements by the plaintiff's law firms and OpenAI. Applies to s1.
Event countries: Unknown. Affected-person countries: United States. Court countries: United States.
KRON4 describes Rosenthal as a Washington man (a US location whether the state or the capital is meant). The suit was filed in San Francisco Superior Court, California. The report does not say where he used ChatGPT or where he was hospitalized, so no event country is recorded.
Reviewed for publication 2026-10-02: Published as a concrete adverse account of an adult ChatGPT user described in a filed lawsuit and reported by KRON4, with every account of ChatGPT outputs and their effects attributed to the plaintiff and his attorneys. The plaintiff sues in his own name.
People described
An adult man from Washington, the plaintiff, who used ChatGPT from the summer of 2025
People reported harmed in this case
1 person
1 AI participant · 0 other people harmed
One person: the plaintiff, who used ChatGPT and whose hospitalizations and losses the suit describes. Exact 1.
Counted once within this case. The same person may appear in other cases. This count does not establish AI causation.
Cite this case
Compiled per our published methodology: verification statuses, sourcing standards, and corrections process.
APA
NOPE. (2026). Rosenthal v. OpenAI: a Washington man says ChatGPT fostered a delusional state of mind, discussed his stopping a mood stabilizer and displaced his relationships, and that he was hospitalized with mania and delusions (lawsuit allegations). AI incidents. https://nope.net/incidents/2025-rosenthal-v-openai-chatgpt-delusions-hospitalization
BibTeX
@misc{2025_rosenthal_v_openai_chatgpt_delusions_hospitalization,
title = {Rosenthal v. OpenAI: a Washington man says ChatGPT fostered a delusional state of mind, discussed his stopping a mood stabilizer and displaced his relationships, and that he was hospitalized with mania and delusions (lawsuit allegations)},
author = {NOPE},
year = {2026},
howpublished = {AI incidents},
url = {https://nope.net/incidents/2025-rosenthal-v-openai-chatgpt-delusions-hospitalization}
} Related cases
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