Cyber Security Event
Date: 01-02-2026
Mid Michigan Medical Billing Service, Inc. (“MMMBS”) is a revenue cycle management company that provides billing support to healthcare organizations. MMMBS is providing notice of an event that may affect the security of certain data MMMBS received from its business partners. This notice provides information about the event, MMMBS’s response to date, and the resources available to individuals to help protect their information from possible misuse, should they feel it appropriate to do so.
What Happened? MMMBS became aware of suspicious activity involving its IT network. MMMBS promptly took systems offline and began an investigation. The investigation determined that the network had been accessed by an unknown actor on March 27, 2025, and during this time files were copied and potentially viewed. As a result, MMMBS conducted a detailed review of the files to determine the type of information present and to whom it relates. MMMBS notified the entities associated with this information and worked with them to provide notice to potentially impacted individuals. This process was completed on or around December 2, 2025.
What Information was Involved? The types of information identified through our review varies by individual and MMMBS client but includes name, date of birth, driver’s license or government issued identification number, Medicare/Medicaid identification number, diagnosis/treatment information, medical record number/patient account number, health insurance information, payment card number, employer identification number, passport number, treating/referring provider name, biometric data, and in limited circumstances a Social Security number.
What MMMBS Is Doing. We take this event and the security of information in its care very seriously. We moved quickly to respond and investigate the activity, assess and secure our network, and notify potentially impacted entities and individuals. As part of our ongoing commitment to information security, we are reviewing our existing policies and procedures and enhancing our security measures as appropriate to further protect the security of information in our possession. We also notified federal law enforcement and relevant regulators.
What You Can Do. In general, individuals should remain vigilant against incidents of identity theft and fraud by reviewing account statements, explanation of benefits statements, and monitoring free credit reports for suspicious activity and to detect errors. Suspicious activity should be promptly reported to relevant parties including an insurance company, health care provider, and/or financial institution. Additional information and resources may be found below in the Steps You Can Take to Protect Personal Information section of this notice.
For More Information. For questions on this notice you may contact our dedicated assistance line at 833-303-3875 8:00 a.m. – 8:00 p.m. Eastern Time, Monday through Friday, excluding U.S. holidays.
Monitor Accounts
Under U.S. law, a consumer is entitled to one free credit report annually from each of the three major credit reporting bureaus, Equifax, Experian, and TransUnion. To order a free credit report, visit www.annualcreditreport.com or call, toll-free, 1-877-322-8228. Consumers may also directly contact the three major credit reporting bureaus listed below to request a free copy of their credit report.
Consumers have the right to place an initial or extended “fraud alert” on a credit file at no cost. An initial fraud alert is a one-year alert that is placed on a consumer’s credit file. Upon seeing a fraud alert display on a consumer’s credit file, a business is required to take steps to verify the consumer’s identity before extending new credit. If consumers are the victim of identity theft, they are entitled to an extended fraud alert, which is a fraud alert lasting seven years. Should consumers wish to place a fraud alert, please contact any of the three major credit reporting bureaus listed below.
As an alternative to a fraud alert, consumers have the right to place a “credit freeze” on a credit report, which will prohibit a credit bureau from releasing information in the credit report without the consumer’s express authorization. The credit freeze is designed to prevent credit, loans, and services from being approved in a consumer’s name without consent. However, consumers should be aware that using a credit freeze to take control over who gets access to the personal and financial information in their credit report may delay, interfere with, or prohibit the timely approval of any subsequent request or application they make regarding a new loan, credit, mortgage, or any other account involving the extension of credit. Pursuant to federal law, consumers cannot be charged to place or lift a credit freeze on their credit report. To request a credit freeze, individuals may need to provide some or all of the following information:
- Full name (including middle initial as well as Jr., Sr., II, III, etc.);
- Social Security number;
- Date of birth;
- Addresses for the prior two to five years;
- Proof of current address, such as a current utility bill or telephone bill;
- A legible photocopy of a government-issued identification card (state driver’s license or ID card, etc.); and
- A copy of either the police report, investigative report, or complaint to a law enforcement agency concerning identity theft if they are a victim of identity theft.
Should consumers wish to place a credit freeze or fraud alert, please contact the three major credit reporting bureaus listed below:
| Equifax | Experian | TransUnion |
| https://www.equifax.com/personal/credit-report-services/ | https://www.experian.com/help/ | https://www.transunion.com/credit-help |
| 1-888-298-0045 | 1-888-397-3742 | 1-833-799-5355 |
| Equifax Fraud Alert, P.O. Box 105069 Atlanta, GA 30348-5069 | Experian Fraud Alert, P.O. Box 9554, Allen, TX 75013 | TransUnion Fraud Alert, P.O. Box 2000, Chester, PA 19016 |
| Equifax Credit Freeze, P.O. Box 105788 Atlanta, GA 30348-5788 | Experian Credit Freeze, P.O. Box 9554, Allen, TX 75013 | TransUnion Credit Freeze, P.O. Box 160, Woodlyn, PA 19094 |
Additional Information
Consumers may further educate themselves regarding identity theft, fraud alerts, credit freezes, and the steps they can take to protect your personal information by contacting the consumer reporting bureaus, the Federal Trade Commission, or their state Attorney General. The Federal Trade Commission may be reached at: 600 Pennsylvania Avenue NW, Washington, D.C. 20580; www.identitytheft.gov; 1-877-ID-THEFT (1-877-438-4338); and TTY: 1-866-653-4261. The Federal Trade Commission also encourages those who discover that their information has been misused to file a complaint with them. Consumers can obtain further information on how to file such a complaint by way of the contact information listed above. Consumers have the right to file a police report if they ever experience identity theft or fraud. Please note that in order to file a report with law enforcement for identity theft, consumers will likely need to provide some proof that they have been a victim. Instances of known or suspected identity theft should also be reported to law enforcement and the relevant state Attorney General.