Plymouth-based hearing aid company Miracle-Ear Inc. said Friday that 554 patient records tied to its Coon Rapids location were compromised in a security breach to its e-mail system.

The incident occurred Oct. 24, when “an unknown and unauthorized intruder” gained access to the e-mail account of an employee in the legal department of Miracle-Ear’s parent company, Amplifon, which handles accounts and administrative work.

The privacy breach was discovered the next morning.

Miracle-Ear officials said no Social Security numbers or financial information were exposed by the incident, which company spokeswoman Andi Ruth-Negrini described as the work of outside hackers.

The compromised e-mail account included a spreadsheet with “excerpts” of patient records from the Best Hearing branch in Coon Rapids. The spreadsheet contained names, addresses, birthdays, dates of hearing aid purchase, hearing test results and contact information.

The company sent letters on Tuesday to those affected. Asked why it took two months to alert their clients, Ruth-Negrini said the breach needed to be fully investigated to determine its scale and scope. She did not know whether law enforcement was involved.

“We understand that this situation may upset or pose an inconvenience to our customers and sincerely apologize and regret this occurrence,” Miracle-Ear officials said in a statement.

Federal law requires that businesses and vendors of personal health records provide notification following a breach of unsecured protected health information. Specifically, notifications must be sent “without reasonable delay and in no case later than 60 days following the discovery of a breach.”

Miracle-Ear is one of the best-known hearing aid brands in the nation. It operates a network of franchised and corporate-owned retail stores at more than 1,400 U.S. locations.

Those with questions may contact Miracle-Ear by e-mail at and at a dedicated toll-free line at 877-778-5416.

Individuals may also write to Miracle-Ear Inc., Attn: Customer Care Team, 5000 Cheshire Pkwy. N., Plymouth, MN 55446.