Marshfield Clinic Health System has been informed by Welltok, Inc., a vendor that provides mailing services, that Welltok experienced a security incident that impacted some of our patients' personal information. Welltok will be reaching out to patients affected. Welltok is communicating directly with patients by letter about the situation and next steps. The letter from Welltok is not a scam. This incident did not impact systems at Marshfield Clinic. If you have questions, visit www.welltok.com for more information about the incident to view this notice.