Press Release

January 6, 2011

Authentidate Holding Corp. (Nasdaq: ADAT), a worldwide provider of secure health information exchange, workflow management services and telehealth solutions, today announced that in accordance with its terms, the company’s current contract with the United States Postal Service® (USPS®) for the use of the USPS Electronic Postmark® (USPS EPM®) brand has been allowed to expire as of December 31, 2010. The USPS has notified the company that it hopes to develop a revised framework for the next generation of the USPS EPM and may revamp the program in the future. The USPS and the company will endeavor to work together to ensure a smooth transition from the USPS EPM brand, which includes a verification service for existing USPS EPMs for the required seven-year period.

Mr. Ben Benjamin, President of Authentidate, stated, “We plan to support the USPS as they determine what their business strategy going forward will be for the USPS EPM. We will continue to provide our customers with uninterrupted content authentication and time and date stamping services under the Authentidate brand as we transition from the USPS brand. In addition, this transition will not impact the performance or capabilities of our other products and solutions, including our suite of Incsrybe® offerings and the telehealth services provided through Express MD^TM Solutions. We appreciate the long-term business relationship that we have enjoyed with the USPS and we plan on working with them to insure a smooth transition for our mutual customers and on the future of the USPS EPM.”