MARTA said the personal information, including Social Security numbers and dates of birth, of 785 of its employees was mailed to the wrong addresses because of an equipment malfunction.

The glitch occurred June 8 and was discovered June 12, MARTA said in a news release issued Wednesday. The employees were notified June 16.

The information was sent out during enrollment for critical care insurance.

In a statement, MARTA said that it “regrets any inconvenience this may have caused affected employees. This incident represents a very limited breach related solely to employee personally identifiable information and had no impact on our customers.”

MARTA said that in response to the information compromise, it is providing the employees with a year of free credit monitoring. It also said it will train or re-train employees responsible for distributing information.