City of Hope Data Breach Investigation

Stueve Siegel Hanson, a national leader in data breach and privacy cases, is investigating potential claims against City of Hope resulting from a data breach that exposed patients’ sensitive personal and health information.

If you receive a notification that your information may have been compromised in this breach, please fill out a contact form below.

City of Hope Data Breach

City of Hope is a California-based cancer treatment and research center with a national network of hospitals and clinical locations across the United States.

On April 2, 2024, City of Hope filed a notice with the Attorney General of Maine describing a cybersecurity incident affecting patients nationwide. According to the notice, the data breach occurred between September 19, 2023, and October 12, 2023, impacting over 820,000 patients.


The stolen information includes names, contact information (e.g., email address, phone number), dates of birth, Social Security numbers, driver’s licenses or other government identification, financial details (e.g., bank account number and/or credit card details), health insurance information, medical records, medical history and/or associated conditions, and/or unique identifiers to associate individuals with City of Hope (e.g., medical record number).


If you receive a notification that your personal information may have been compromised in this breach, please contact our team by filling out the form below.


Stueve Siegel Hanson attorneys have represented data breach victims in many of the nation’s largest data breach class actions, including cases against EquifaxT-Mobile, Capital One and many others – securing much-needed relief for millions of affected consumers.

The firm’s Data Breach and Privacy class action practice has received local and national recognition, including being named a Cybersecurity & Privacy Practice Groups of the Year by Law360, which recognizes practice groups that “worked on the biggest deals or achieved the biggest wins in the most important cases.”

City of Hope Data Breach Lawsuit Investigation

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