UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM SD

Specialized Disclosure Report

COHERENT, INC.

Check the appropriate box to indicate the rule pursuant to which this form is being filed, and provide the period to which the information in this form applies:

x Rule 13p-1 under the Securities Exchange Act (17 CFR 240.13p-1) for the reporting period from January 1 to December 31, 2017.

Section 1 - Conflict Minerals Disclosure

Item 1.01              Conflict Minerals Disclosure and Report

A copy of the Conflict Minerals Report of Coherent, Inc. (“Coherent”) is filed as Exhibit 1.01 hereto and is publicly available on Coherent’s website at: https://cohrcdn.azureedge.net/assets/pdf/Conflict_Minerals_Report_2017_Calendar_Year_End.pdf.

The full text of Coherent’s Conflict Minerals Policy is publicly available on Coherent’s website at https://cohrcdn.azureedge.net/assets/pdf/ConflictMinerals_Policy_Dec2013.pdf.

Any websites referenced in this Form SD and the information accessible through them are not incorporated in this Form SD.

Item 1.02              Exhibit

The Conflict Minerals Report required by Item 1.01 is filed as Exhibit 1.01 to this Form SD.

Section 2 - Exhibits

Item 2.01              Exhibits

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SIGNATURES

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 duly authorized undersigned.

COHERENT, INC.

(Registrant)

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