At least 5.6 million people had their names, addresses, dates of birth, and Social Security numbers stolen in a data breach at 700Credit, a company that runs credit checks and identity verification services for auto dealerships across the United States.

In a statement on its website, the Michigan-based company blamed the October data breach on an unidentified bad actor.

According to Michigan’s attorney general, the hacker stole personal data collected from dealers between May and October 2025.

The company said it was now sending letters by mail to individuals whose information had been stolen in the data breach, which offers credit monitoring services.

“If you get a letter from 700Credit, don’t ignore it,” said Michigan attorney general Dana Nessel. “It is important that anyone affected by this data breach takes steps as soon as possible to protect their information. A credit freeze or monitoring services can go a long way in preventing fraud, and I encourage Michiganders to use the tools available to keep their identity safe.”