Someone broke into an office building February 4 and took the laptops. They were password protected and the data was in a format that could not be easily read by someone outside the hospital.
Nevertheless, nearly 5,500 patients have been sent letters to tell them that their personal information may have been compromised.
"We've giving them information on how to put a fraud alert on their credit report to alert the credit monitoring companies if any unusual activity takes place, then they will notify the patient," John Muir spokesperson Hala Helm said.
In addition, the hospital is working with a credit reporting agency to give the patients a year's free access to their credit reports.