Strauss Borrelli PLLC, a leading data breach law firm, is investigating Marin Cancer Care (“MCC”) regarding its recent data breach. The MCC data breach involved sensitive personal information and protected health information belonging to an undetermined number of individuals.
ABOUT MARIN CANCER CARE:
MCC is a cancer treatment center based in California. Founded in 1978, MCC provides a range of cancer treatment services to patients, including medical oncology, radiation oncology, hematology, clinical trials, and more.2,3 Headquartered in Greenbae, California, MCC employs over 10 individuals.3
WHAT HAPPENED?
Recently, MCC announced that it had experienced a data breach in which sensitive personal identifiable information and protected health information in its care may have been compromised. According to the breach notice shared on its website, on or about December 8, 2025, MCC learned that its computer network was accessed without permission and that certain files may have been copied and taken from the network.1 As a result, MCC launched an investigation to determine the nature of the incident.
Through its investigation, MCC confirmed that sensitive personal information in its network may have been accessed and acquired by an unauthorized third party between November 22 and December 6, 2025. As a result, MCC began a review of the data to determine what information had been impacted as well as identify the specific individuals affected. While the information impacted varies depending on the individual, the type of information potentially exposed includes:
- Name
- Medical information
- Health insurance information
On February 6, 2026, MCC posted notice of the breach on its website and filed official notice of the data breach with the U.S. Department of Health and Human Services’ Office for Civil Rights.4 Based on the website breach notice, MCC is providing affected individuals with a list of the specific types of sensitive information impacted and complimentary credit monitoring services. A link to the website breach notice is below.
If you believe you have been affected by the Marin Cancer Care breach:
We would like to speak with you about your rights and potential legal remedies in response to this data breach. Please fill out the form, below, or contact us at 872.263.1100 or sam@straussborrelli.com.
