UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15 (d)

OF THE SECURITIES EXCHANGE ACT OF 1934

DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): March 18, 2015

AUTHENTIDATE HOLDING CORP.

(Exact name of registrant as specified in its charter)

COMMISSION FILE NUMBER: 0-20190

Connell Corporate Center

300 Connell Drive, 5^th Floor

Berkeley Heights, New Jersey 07922

(Address and zip code of principal executive offices)

(908) 787-1700

(Registrant’s telephone number, including area code

CHECK THE APPROPRIATE BOX BELOW IF THE FORM 8-K FILING IS INTENDED TO SIMULTANEOUSLY SATISFY THE FILING OBLIGATION OF THE REGISTRANT UNDER ANY OF THE FOLLOWING PROVISIONS:

On March 18, 2015, Authentidate Holding Corp. (the “Company”) hosted a conference call regarding recent corporate developments and the Company’s plans. A copy of the prepared remarks of the Company’s Chief Executive Officer is filed as Exhibit 99.1 to this Current Report on Form 8-K.

In accordance with General Instruction B.2. of Form 8-K, this information, including Exhibit 99.1 furnished herewith, is furnished pursuant to Item 7.01 and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be incorporated by reference into a filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act. The information in this Item 7.01 of this Current Report on Form 8-K (including the exhibits hereto) will not be deemed an admission as to the materiality of any information required to be disclosed solely to satisfy the requirements of Regulation FD.

“Safe Harbor” Statement under the Private Securities Litigation Reform Act of 1995:

Certain statements in this Current Report on Form 8-K and the exhibit attached hereto are “forward-looking” statements within the meaning of the Private Securities Litigation Reform Act of 1995 with respect to future events and financial performance. When used in this report and the exhibit, the words “believe,” “anticipate,” “think,” “intend,” “plan,” “will be,” “expect,” and similar expressions identify such forward-looking statements. Such statements regarding future events and/or the future financial performance of the Company are subject to certain risks and uncertainties, which could cause actual events or the actual future results of the Company to differ materially from any forward-looking statement. Such risks and uncertainties are described in the Company’s press releases and filings with the Securities and Exchange Commission and include, among other things, the availability of any needed financing, the Company’s ability to implement its business plan for various applications of its technologies, the impact of competition, the management of growth. In light of the significant risks and uncertainties inherent in the forward-looking statements included herein, the inclusion of such statements should not be regarded as a representation by the Company or any other person that the objectives and plans of the company will be achieved. The Company undertakes no obligation to update any forward looking statement.

The following exhibit is attached to this Form 8-K:

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.

Date: March 18, 2015

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EXHIBIT INDEX

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