Cytek Biosciences Data Breach Exposes Social Security Numbers

On Dec. 22, 2025, Cytek Biosciences, Inc., which specializing in flow cytometry equipment and solutions, disclosed a data breach that exposed sensitive consumer information. So far, at least 331 individuals have been impacted by the cybersecurity incident, including eight residents of Massachusetts and one of Maine.

The breach exposed a wide array of sensitive information including personally identifiable information (PII) such as names, contact information (postal address, email address, phone number), dates of birth, Social Security numbers, driver’s license numbers, government-issued ID numbers, citizenship status, signatures, financial account and compensation information, as well as Cytek employee account usernames and passwords. In addition, protected health information (PHI) such as health and medical records was also involved.

On Dec. 22, 2025, the company disclosed the data breach to the Attorney Generals' offices in Maine and Massachusetts. Impacted individuals have been notified by mail.

Cytek Biosciences' response

In response to the breach, Cytek has taken several steps to support affected individuals. The company is offering 24 months of complimentary identity protection and credit monitoring services through Experian IdentityWorks. This service includes daily credit report monitoring, identity restoration assistance, and up to $1 million in identity theft insurance. Affected individuals can enroll in these services until April 30, 2026, and do not need to provide a credit card for enrollment.

Those impacted are encouraged to remain vigilant by regularly reviewing account statements and credit reports for suspicious activity. Cytek has also provided a dedicated toll-free response line at 833-918-1243 for questions and support, available Monday through Friday from 8 a.m. to 8 p.m. Central time, excluding major U.S. holidays.

Given the nature of the information exposed, including Social Security numbers, financial account data, and health records, affected individuals should consider placing a security freeze or fraud alert on their credit files. The official notice provides detailed instructions on how to do so, as well as contact information for the three major credit bureaus.