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): November 5, 2018

Diamond Offshore Drilling, Inc.

(Exact name of registrant as specified in its charter)

15415 Katy Freeway

Houston, Texas 77094

(Address of principal executive offices, including Zip Code)

(281) 492-5300

(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:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

On November 5, 2018, Diamond Offshore Drilling, Inc. (the “Company”) issued a press release announcing its financial results for the fiscal quarter ended September 30, 2018. A copy of the press release is furnished herewith as Exhibit 99.1.

Earnings Conference Call

A conference call to discuss the Company’s earnings results has been scheduled for 8:00 a.m. Central Time on November 5, 2018. The information for accessing the conference call is included in the press release.

Rig Status Report

The Company hereby incorporates by reference into this Item 7.01 the summary report of the status, as of November 5, 2018, of the Company’s offshore drilling rigs attached as Exhibit 99.2.

The information contained in Items 2.02 and 7.01 and Exhibits 99.1 and 99.2 to this report shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and shall not be incorporated by reference into any previous or future registration statement filed under the Securities Act of 1933, as amended (the “Securities Act”), unless specifically identified therein as being incorporated by reference.

Statements in this report, statements in the press release furnished as Exhibit 99.1 to this report or the rig status report furnished as Exhibit 99.2 to this report, and statements made during the conference call described in this report, in each case that are not historical facts are “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Such statements include, but are not limited to, statements concerning future contract effectiveness and estimated duration; expectations regarding rig dayrates, downtime, reactivation, surveys, retirement, availability, utilization and scrapping; expectations regarding future impairments; expectations of future backlog and revenue expected to result from backlog; expectations of future revenue, operating costs and performance; future liquidity, financial condition, market conditions, commodity prices and strategic opportunities; contract noncompliance by customers and other third parties; rights, obligations and future actions under letters of intent; outcomes of customer discussions; future impact of regulations; future outcome of litigation; and other statements that are not of historical fact. Forward-looking statements are inherently uncertain and subject to a variety of assumptions, risks and uncertainties that could cause actual results to differ materially from those currently anticipated or expected by management of the Company. A discussion of certain of the risk factors and other considerations that could materially impact these matters as well as the Company’s overall business and financial performance can be found in the Company’s reports filed with the Securities and Exchange Commission, and readers of this report are urged to review those reports carefully when considering these forward-looking statements. These risk factors include, among others, risks associated with worldwide demand for drilling services, level of activity in the oil and gas industry, renewing or replacing expired or terminated contracts, contract

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cancellations and terminations, maintenance and realization of backlog, competition and industry fleet capacity, litigation and disputes, operating risks and various other factors, many of which are beyond the Company’s control. Given these risk factors and other considerations, investors and analysts should not place undue reliance on forward-looking statements. Each forward-looking statement speaks only as of the date of such statement, and the Company expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statement to reflect any change in the Company’s expectations with regard thereto or any change in events, conditions or circumstances on which any forward-looking statement is based.

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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 undersigned hereunto duly authorized.

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