San Mateo County Transit District (SMCTD) notified individuals of a data security incident on May 23, 2022. On June 2, 2021, SMCTD detected unusual activity in its email environment and launched an investigation. The investigation determined that unauthorized access occurred to certain employee email accounts. A comprehensive analysis concluded on March 2, 2022, that some individuals' personal information (names and other variable data) resided in the accessed accounts. SMCTD stated there is no evidence the information itself was accessed without authorization or misused. The organization secured its email environment, implemented enhanced security measures, notified the FBI, and offered one year of complimentary identity monitoring and protection services through IDX.