Onsite Mammography Data Breach

Attorneys working with ClassAction.org are looking into whether a class action lawsuit can be filed in light of the Onsite Mammography data breach.

As part of their investigation, they need to hear from individuals who received a notice stating they were impacted.

Onsite Mammography, LLC recently announced it experienced a data breach affecting 357,265 people. Onsite Mammography is located in Westfield, Massachusetts and provides specialized in-office breast health and imaging services.

The healthcare provider identified unusual activity involving an employee’s email account on October 4, 2024, and, after securing the email environment, engaged independent cybersecurity experts to investigate the incident. Investigators determined an unauthorized party briefly gained access to one employee’s email account but did not access any other company systems or networks.

Onsite Mammography also engaged a third-party data analytics firm to conduct a review of the affected files. The review concluded on February 21, 2025, finding that the compromised data included patients’ health information. 

According to a report submitted to the Texas Attorney General's Office, Social Security numbers and dates of birth may have also been exposed. 

Affected individuals are receiving personalized letters detailing the specific data elements, in addition to names, that were compromised in the Onsite Mammography data breach.

If your information was exposed in the data breach, attorneys want to hear from you. You may be able to start a class action lawsuit to recover compensation for loss of privacy, time spent dealing with the breach, out-of-pocket costs, and more.

A successful case could also force Onsite Mammography to ensure it takes proper steps to protect the information it was entrusted with.