As filed with the Securities and Exchange Commission on September 28, 2018

Registration No. 333-          

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

MCDERMOTT INTERNATIONAL, INC.

(Exact name of registrant as specified in its charter)

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

John M. Freeman

Executive Vice President,

Chief Legal Officer & Corporate Secretary

757 N. Eldridge Parkway

Houston, Texas 77079

(281) 870-5000

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:

Ted W. Paris

James H. Mayor

Baker Botts L.L.P.

910 Louisiana Street

Houston, Texas 77002

(713) 229-1234

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box:  ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”), other than securities offered only in connection with dividend or interest reinvestment plans, check the following box:  ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ☒

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act (Check one):

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 7(a)(2)(B) of the Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

Prospectus

MCDERMOTT INTERNATIONAL, INC.

Senior Debt Securities

Subordinated Debt Securities

Common Stock

Preferred Stock

Warrants

Stock Purchase Contracts

Stock Purchase Units

The Offering

This prospectus describes some of the general terms that may apply to our securities. We will provide additional terms of our securities in one or more supplements to this prospectus. You should read this prospectus and the related prospectus supplement carefully before you invest in our securities. No person may use this prospectus to offer and sell our securities unless a prospectus supplement accompanies this prospectus.

Our common stock is listed on the New York Stock Exchange under the symbol “MDR.”

Investing in our securities involves risks that are referenced in the “Risk Factors” section on page 1 of this prospectus. In addition, risk associated with any investment in our securities may be described in the applicable prospectus supplement and our other filings with the Securities and Exchange Commission, as described in the “Risk Factors” section on page 1 of this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is September 28, 2018.

Table of Contents

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About This Prospectus

This prospectus is part of a registration statement that we have filed with the U.S. Securities and Exchange Commission (the “SEC”) using a “shelf” registration process. Under this shelf registration process, we may offer any combination of the securities this prospectus describes in one or more offerings. This prospectus provides you with a general description of the securities we may offer. Each time we use this prospectus to offer securities, we will provide a prospectus supplement that will describe the specific terms of the offering. The prospectus supplement may also add to, update or change the information contained in this prospectus. Please carefully read this prospectus and the prospectus supplement in addition to the information contained in the documents we refer to under the heading “Where You Can Find More Information.”

The Company

McDermott International, Inc. (“McDermott,” “MDR,” “we,” “our,” “us” or the “Company”), a corporation incorporated under the laws of the Republic of Panama in 1959, is a fully-integrated provider of engineering, procurement, construction and installation (“EPCI”) and technology solutions to the energy industry. On May 10, 2018, we completed our combination with Chicago Bridge & Iron Company N.V. (“CB&I”) through a series of transactions. We design and build end-to-end infrastructure and technology solutions, from the wellhead to the storage tank, to transport and transform oil and gas into a variety of products. Our proprietary technologies, integrated expertise and comprehensive solutions are utilized for offshore, subsea, power, liquefied natural gas (“LNG”) and downstream energy projects around the world. Our customers include national, major integrated and other oil and gas companies as well as producers of petrochemicals and electric power, and we operate in most major energy producing regions throughout the world. We execute our contracts through a variety of methods, principally fixed-price, but also including cost reimbursable, cost-plus, day-rate and unit-rate basis or some combination of those methods.

In this prospectus, unless the context otherwise indicates, “McDermott,” “we,” “us” and “our” mean McDermott International, Inc. and its consolidated subsidiaries. Our principal executive offices are located at 757 N. Eldridge Parkway, Houston, Texas 77079, and our telephone number at that location is (281) 870-5000.

Risk Factors

Investing in our securities involves risks. You should carefully consider the specific risks set forth under the caption “Risk Factors” in the applicable prospectus supplement, and under the caption “Risk Factors” in any of our filings with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), incorporated by reference in this prospectus, before making an investment decision. For more information, see “Where You Can Find More Information.”

Where You Can Find More Information

We file annual, quarterly and current reports, proxy statements and other information with the SEC. You can read and copy these materials at the SEC’s public reference room at 100 F Street, N.E., Washington, D.C. 20549. You can obtain information about the operation of the SEC’s public reference room by calling the SEC at 1-800-732-0330. The SEC also maintains a Web site that contains information we have filed electronically with the SEC, which you can access over the Internet at www.sec.gov. You can also obtain information about us at the offices of the New York Stock Exchange, 20 Broad Street, New York, New York 10005.

This prospectus is part of a registration statement we have filed with the SEC relating to the securities we may offer. As permitted by SEC rules, this prospectus does not contain all the information we have included in

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the registration statement and the accompanying exhibits we have filed with the SEC. You may refer to the registration statement and exhibits for more information about us and the securities. The registration statement and exhibits are available at the SEC’s public reference room or through its Web site.

The SEC allows us to “incorporate by reference” the information we have filed with it, which means that we can disclose important information to you by referring you to those documents. The information we incorporate by reference is an important part of this prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than information “furnished” and not “filed” with the SEC, unless we specifically provide that such “furnished” information is to be incorporated by reference) after the date of this prospectus and until the termination of this offering. The documents we incorporate by reference are:

You may request a copy of these filings, other than an exhibit to these filings unless we have specifically incorporated that exhibit by reference into the filing, at no cost, by writing to or telephoning us at:

McDermott International, Inc.

757 N. Eldridge Parkway

Houston, Texas 77079

Attention: Investor Relations

Telephone: (281) 870-5000

We have not authorized anyone to provide any information or to make any representations other than those contained or incorporated by reference in this prospectus, the prospectus supplement or any free writing prospectus prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not making an offer of the securities in any jurisdiction where the offer is not permitted. You should assume that the information in this prospectus, the prospectus supplement and any free writing prospectus is accurate only as of their respective dates and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference.

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Enforceability of Civil Liabilities

We are a corporation organized under the laws of the Republic of Panama, and a substantial amount of our assets are or may be located in jurisdictions outside the United States. Accordingly, it may be difficult or impossible to enforce judgments against us, including judgments predicated on the civil liability provisions of the federal securities laws of the United States. Because a substantial amount of our assets are located outside the United States, any judgment obtained in the United States against us may not be fully collectible in the United States. In addition, treaties may not exist in all cases for the recognition of the enforcement of a judgment or order of a foreign court. We have been advised by our counsel in the Republic of Panama, Arias, Fabrega and Fabrega, that courts in the Republic of Panama will enforce a foreign judgment for a liquidated amount in civil matters, subject to obtaining a writ from the Supreme Court of Panama, which would require the satisfaction of certain conditions and exceptions, including that: (1) the foreign court that granted the judgment grants reciprocity to the enforcement of judgments of courts of the Republic of Panama (which, in practice, the Supreme Court of Panama will presume to be the case, unless proved otherwise); (2) the party against whom the judgment was rendered, or its agent, was personally (not by mail) served in such action; (3) the judgment arises out of a personal action (i.e., not an “in rem” action) against the defendant; (4) the obligation in respect of which the judgment was rendered is lawful in the Republic of Panama and does not contradict the public policy of Panama; (5) the judgment is properly authenticated by diplomatic or consular officers of the Republic of Panama or pursuant to the 1961 Hague Convention Abolishing the Requirement of Legalisation of Foreign Public Documents; and (6) a copy of the final judgment is translated into Spanish by a licensed translator in Panama. Subject to customary assumptions, Arias, Fabrega and Fabrega has advised us that they know of no current public policy that would prevent or hinder the enforcement of such a final judgment in the Republic of Panama. Courts in the Republic of Panama will not enforce in original actions liabilities predicated solely on the United States federal securities laws.

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Forward-Looking Statements

This prospectus, including the documents incorporated by reference in this prospectus, contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may include projections and estimates concerning the scope, execution, timing and success of specific projects and our future RPOs, revenues, income and capital spending. Forward-looking statements are generally accompanied by words such as “achieve,” “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “seek,” “should,” “strategy” or other words that convey the uncertainty of future events or outcomes. Sometimes we will specifically describe a statement as being a forward-looking statement and refer to this cautionary statement. In addition, various statements in this prospectus, including those that express a belief, expectation or intention, as well as those that are not statements of historical fact, are forward-looking statements. These forward-looking statements include, but are not limited to, statements that relate to, or statements that are subject to risks, contingencies or uncertainties that relate to:

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These forward-looking statements speak only as of the date of this prospectus; we disclaim any obligation to update these statements unless required by securities law, and we caution you not to rely on them unduly. We have based these forward-looking statements on our current expectations and assumptions about future events. While our management considers these expectations and assumptions to be reasonable, they are inherently subject to significant business, economic, competitive, regulatory and other risks, contingencies and uncertainties, most of which are difficult to predict and many of which are beyond our control. These risks, contingencies and uncertainties relate to, among other matters, the following:

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We believe the items we have outlined above are important factors that could cause estimates in our financial statements to differ materially from actual results and those expressed in a forward-looking statement made in this prospectus, any prospectus supplement, the documents incorporated herein by reference or elsewhere by us or on our behalf. We have discussed many of these factors in more detail elsewhere in the documents we have incorporated by reference and may discuss these factors in more detail in any prospectus supplement. These factors are not necessarily all the factors that could affect us. Unpredictable or unanticipated factors we have not discussed in this prospectus could also have material adverse effects on actual results of matters that are the subject of our forward-looking statements. We do not intend to update our description of important factors each time a potential important factor arises, except as required by applicable securities laws and regulations. We advise investors that they should (1) be aware that factors not referred to above could affect the accuracy of our forward-looking statements and (2) use caution and common sense when considering our forward-looking statements.

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Use of Proceeds

Unless we inform you otherwise in a prospectus supplement, we expect to use the net proceeds from the sale of the securities under this prospectus for general corporate purposes. These purposes may include the repayment or refinancing of indebtedness and funding for acquisitions, working capital requirements, capital expenditures and repurchases and redemptions of securities. Pending any specific application, we may initially invest funds in short-term marketable securities or apply them to the reduction of short-term indebtedness.

Ratios of Earnings to Fixed Charges and Earnings

to Combined Fixed Charges and Preferred Stock Dividends

Our ratios of earnings to fixed charges and earnings to combined fixed charges and preferred stock dividends for each of the periods indicated, in each case determined on a total enterprise basis, are as follows:

For purposes of this table, “earnings” consist of pre-tax income from continuing operations before provision for noncontrolling interest, interest expense and our portion of rents representative of the interest factor. “Fixed charges” consist of interest expensed and capitalized and our portion of rents representative of the interest factor.

We had no preferred stock outstanding for any period presented in the table above so, accordingly, our ratio of earnings to combined fixed charges and preferred stock dividends is the same as our ratio of earnings to fixed charges.

Description of Debt Securities

The debt securities this prospectus covers will be our general unsecured obligations. The debt securities will be either senior debt securities or subordinated debt securities. We will issue the debt securities under one or more separate indentures between us and a trustee that we will name in the prospectus supplement. Senior debt securities will be issued under a senior indenture, and subordinated debt securities will be issued under a subordinated indenture. In this description, we sometimes call the senior indenture and the subordinated indenture the “indentures.”

We have summarized the provisions of the indentures and the debt securities below. You should read the indentures for more details regarding the provisions described below and for other provisions that may be important to you. We have filed the forms of indentures with the SEC as exhibits to the registration statement, and we will include the applicable final indenture and any other instrument establishing the terms of any debt securities we offer as exhibits to a filing we will make with the SEC in connection with that offering. See “Where You Can Find More Information.”

In this summary description of the debt securities, all references to “McDermott,” “we” or “us” mean McDermott International, Inc. only, unless we state otherwise or the context clearly indicates otherwise.

General

The senior debt securities will constitute our senior debt and will rank equally with all of our unsecured and unsubordinated debt. The subordinated debt securities will be subordinated to, and thus have a position junior to,

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any senior debt securities and all our other senior debt. The indentures will not limit the amount of debt we may issue under the indentures, and, unless we inform you otherwise in the prospectus supplement, they will not limit the amount of other unsecured debt or securities we may incur or issue. We may issue debt securities under either indenture from time to time in one or more series, each in an amount we authorize prior to issuance.

We derive substantially all of our operating income from, and hold substantially all our assets through, our subsidiaries. As a result, we will depend on distributions of cash flow and earnings of our subsidiaries in order to meet our payment obligations under any debt securities we offer under this prospectus and our other obligations. These subsidiaries are separate and distinct legal entities and will have no obligation to pay any amounts due on our debt securities or to provide us with funds for our payment obligations, whether by dividends, distributions, loans or otherwise. In addition, provisions of applicable law, such as those limiting the legal sources of dividends, could limit their ability to make payments or other distributions to us and they could agree to contractual restrictions on their ability to make distributions. In addition, holders of the debt securities will have a junior position to the claims of creditors of our subsidiaries on their assets and earnings.

Our right to receive any assets of any subsidiary, and therefore the right of the holders of our debt securities to participate in those assets, will be effectively subordinated to the claims of that subsidiary’s creditors, including trade creditors. In addition, even if we are a creditor of any subsidiary, our rights as a creditor would be subordinate to any security interest in the assets of that subsidiary and any indebtedness of that subsidiary senior to that held by us.

We may issue the debt securities of any series in definitive form or as a book-entry security in the form of a global security registered in the name of a depositary we designate.

We may issue the debt securities in one or more series with various maturities, and we may sell those debt securities at par, at a premium or with an original issue discount.

Terms

A prospectus supplement relating to any series of debt securities being offered will specify whether the debt securities are senior debt securities or subordinated debt securities and will include specific terms relating to the offering. These terms will include some or all of the following:

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If we sell any of the debt securities for any foreign currency or currency unit or if payments on the debt securities are payable in any foreign currency or currency unit, we will describe in the prospectus supplement the restrictions, elections, tax consequences, specific terms and other information relating to those debt securities and the foreign currency or currency unit.

Subordination

Under the subordinated indenture, payment of the principal, interest and any premium on the subordinated debt securities will generally be subordinated and junior in right of payment to the prior payment in full of all Senior Debt (as defined below). Unless we inform you otherwise in the prospectus supplement, we may not make any payment of principal, interest or any premium on the subordinated debt securities if:

Unless we inform you otherwise in the prospectus supplement, a covenant default will prevent us from making payments on the subordinated debt securities only for up to 179 days after holders of the Senior Debt give the trustee for the subordinated debt securities notice of the covenant default.

The subordination provisions will not affect our obligation, which will be absolute and unconditional, to pay, when due, principal of, premium, if any, and interest on the subordinated debt securities. In addition, the subordination provisions will not prevent the occurrence of any default under the subordinated indenture.

Unless we inform you otherwise in the prospectus supplement, the subordinated indenture will not limit the amount of Senior Debt that we may incur. As a result of the subordination of the subordinated debt securities, if we become insolvent, holders of subordinated debt securities may receive less on a proportionate basis than our other creditors.

Unless we inform you otherwise in the prospectus supplement, “Senior Debt” will mean all notes or other indebtedness, including guarantees, of McDermott for money borrowed and similar obligations, unless the indebtedness states that it is not senior to the subordinated debt securities or our other junior debt.

Consolidation, Merger and Sale of Assets

The indentures generally will permit a consolidation, amalgamation or merger between us and another entity. They also will permit the sale by us of our assets substantially as an entirety. The indentures will provide,

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however, that we may consolidate or amalgamate with another entity to form a new entity or merge into any other entity or transfer or dispose of our assets substantially as an entirety to any other entity only if:

On the assumption by the successor of the obligations under the indenture, the successor will be substituted for us, and we will be relieved of any further obligation under the indenture and the debt securities.

Events of Default

Unless we inform you otherwise in the prospectus supplement, the following will be events of default with respect to a series of debt securities:

A default under one series of debt securities will not necessarily be a default under another series. The trustee may withhold notice to the holders of the debt securities of any default or event of default, except in any payment on the debt securities, if the trustee in good faith determines that withholding notice is in the interest of the holders of the debt securities.

If an event of default for any series of debt securities occurs and is continuing, the trustee or the holders of at least 25% in principal amount of the outstanding debt securities of the series affected by the default, or, in some cases, 25% in principal amount of all senior debt securities or subordinated debt securities affected, voting as one class, may declare the principal of and all accrued and all unpaid interest on those debt securities to be immediately due and payable. If an event of default relating to events of bankruptcy, insolvency or reorganization occurs, the principal of and all accrued and unpaid interest on all the debt securities will become immediately due and payable without any action on the part of the applicable trustee or any holder. The holders of a majority in principal amount of the outstanding debt securities of the series affected by the default, or of all senior debt securities or subordinated debt securities affected, voting as one class, may in some cases rescind this accelerated payment requirement. Depending on the terms of our other indebtedness, an event of default under either of the indentures may give rise to cross defaults on our other indebtedness.

A holder of a debt security of any series will be able to pursue any remedy under the applicable indenture only if:

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This provision will not, however, affect the right of a holder of a debt security to sue for enforcement of any overdue payment.

In most cases, holders of a majority in principal amount of the outstanding debt securities of a series, or of all debt securities affected, voting as one class, will be able to direct the time, method and place of:

Each indenture will require us to file with the trustee each year a written statement as to our compliance with the covenants contained in that indenture.

Modification and Waiver

We may amend or supplement either indenture if the holders of a majority in principal amount of the outstanding debt securities of all series issued under the applicable indenture and affected by the amendment or supplement, acting as one class, consent to it. Without the consent of the holder of each debt security affected, however, no amendment or supplement may:

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We and the applicable trustee may agree to amend or supplement either indenture or waive any provision of either indenture without the consent of any holders of debt securities in some circumstances, including:

The holders of a majority in principal amount of the outstanding debt securities of any series, or of all senior debt securities or subordinated debt securities affected, voting as one class, may waive any existing or past default or event of default with respect to those debt securities. Those holders may not, however, waive any default or event of default in any payment on any debt security or compliance with a provision that cannot be amended or supplemented without the consent of each holder affected.

Discharge and Defeasance

We will be discharged from all obligations under the applicable indenture with respect to any series of debt securities, except for surviving obligations relating to any conversion rights and to register the transfer or exchange of the debt securities, if:

To exercise our right to be discharged, we must deliver to the applicable trustee an opinion of counsel and an officers’ certificate stating that all conditions precedent to the satisfaction and discharge of the applicable indenture have been complied with.

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In addition to our right of discharge described above, if we deposit with the applicable trustee funds or government securities sufficient to make payments on the debt securities of a series on the dates those payments are due and payable, then, at our option, either of the following will occur:

If we defease a series of debt securities, the holders of the debt securities of the series affected will not be entitled to the benefits of the applicable indenture, except for our obligations to:

Unless we inform you otherwise in the prospectus supplement, we will be required to deliver to the applicable trustee an opinion of counsel that the deposit and related defeasance would not cause the holders of the debt securities to recognize income, gain or loss for United States federal income tax purposes. If we elect legal defeasance, that opinion of counsel must be based on a ruling from the United States Internal Revenue Service or a change in law to that effect.

Governing Law

New York law will govern the indentures and the debt securities.

Trustee

Wells Fargo Bank, National Association, is the trustee under each of the indentures.

If an event of default occurs and is continuing, the trustee must use the degree of care and skill of a prudent person in the conduct of his own affairs. The trustee will become obligated to exercise any of its powers under the indentures at the request of any of the holders of any debt securities only after those holders have offered the trustee indemnity satisfactory to it.

Each indenture will limit the right of the trustee, if it becomes one of our creditors, to obtain payment of claims or to realize on certain property received for any such claim, as security or otherwise. The trustee may engage in other transactions with us. If it acquires any conflicting interest, however, it must eliminate that conflict or resign.

Form, Exchange, Registration and Transfer

We will issue the debt securities in registered form, without interest coupons. We will not charge a service charge for any registration of transfer or exchange of the debt securities. We may, however, require the payment of any tax or other governmental charge payable for that registration.

Debt securities of any series will be exchangeable for other debt securities of the same series with the same total principal amount and the same terms but in different authorized denominations in accordance with the applicable indenture. Holders may present debt securities for registration of transfer at the office of the security registrar or any transfer agent we designate. The security registrar or transfer agent will effect the transfer or exchange when it is satisfied with the documents of title and identity of the person making the request.

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Unless we inform you otherwise in the prospectus supplement, we will appoint the trustee under each indenture as security registrar for the debt securities we issue under that indenture. If the prospectus supplement refers to any transfer agent initially designated by us, we may at any time rescind that designation or approve a change in the location through which any transfer agent acts. We will be required to maintain an office or agency for transfers and exchanges in each place of payment. We may at any time designate additional transfer agents for any series of debt securities or rescind the designation of any transfer agent.

In the case of any redemption, neither the security registrar nor the transfer agent will be required to register the transfer or exchange of any debt security:

Payment and Paying Agent

Unless we inform you otherwise in the prospectus supplement, we will make payments on the debt securities in U.S. dollars at the office of the applicable trustee or any paying agent we designate. At our option, we may make payments by check mailed to the holder’s registered address or, with respect to global debt securities, by wire transfer. Unless we inform you otherwise in the prospectus supplement, we will make interest payments to the person in whose name the debt security is registered at the close of business on the record date for the interest payment.

Unless we inform you otherwise in the prospectus supplement, we will designate the trustee under each indenture as our paying agent for payments on debt securities we issue under that indenture. We may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts.

Subject to the requirements of any applicable abandoned property laws, the trustee and paying agent will repay to us upon written request any funds held by them for payments on the debt securities that remain unclaimed for two years after the date upon which that payment has become due. After repayment to us, holders entitled to those funds must look only to us for payment.

Book-Entry Debt Securities

We may issue the debt securities of a series in the form of one or more global debt securities that would be deposited with a depositary or its nominee identified in the prospectus supplement. We may issue global debt securities in either temporary or permanent form. We will describe in the prospectus supplement the terms of any depositary arrangement and the rights and limitations of owners of beneficial interests in any global debt security.

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Description of Capital Stock

Our authorized capital stock consists of:

Each authorized share of common stock has a par value of $1.00. Each authorized share of preferred stock has a par value of $1.00. As of September 28, 2018, 180,574,259 shares of common stock were issued and outstanding, and 2,838,749 shares of common stock were held as treasury stock. As of September 28, 2018, no shares of our preferred stock were issued and outstanding.

In the discussion that follows, we have summarized the material provisions of our amended and restated articles of incorporation, as amended (our “articles of incorporation”), and amended and restated by-laws (our “by-laws”) relating to our capital stock. This discussion is subject to the relevant provisions of Panamanian Law and is qualified in its entirety by reference to our articles of incorporation and by-laws. You should read the provisions of our articles of incorporation and by-laws as currently in effect for more details regarding the provisions described below and for other provisions that may be important to you. We have filed copies of those documents with the SEC, and they are incorporated by reference as exhibits to the registration statement. See “Where You Can Find More Information.”

Common Stock

Each share of common stock has one vote in the election of each director and on all other matters voted on generally by the stockholders. No share of common stock has any cumulative voting rights. This means that the holders of a majority of the voting power of the shares voting for the election of directors can elect all directors to be elected if they choose to do so. Our board of directors may grant holders of preferred stock, in the resolutions creating the series of preferred stock, the right to vote on the election of directors or any questions affecting us.

The presence at a meeting of our stockholders, in person or by proxy, of holders of a majority of the outstanding shares of common stock as of the record date for that meeting will constitute a quorum. Some business combination transactions require more than a simple majority vote. We have described these business combination transactions below under “—Other Matters—Business Combination Transactions Requiring More Than a Majority Vote.” Otherwise, stockholder approvals generally require the affirmative vote of a majority of the outstanding shares of common stock present in person or represented by proxy at the meeting and entitled to vote and actually voting on the matter.

Holders of common stock will be entitled to dividends in such amounts and at such times as our board of directors in its discretion may declare out of funds legally available for the payment of dividends. We generally do not pay cash dividends, and we intend to retain future earnings to provide funds for use in the operation and expansion of our business. In addition, the payment of dividends on the common stock may be limited by obligations we may have to holders of any preferred stock or by the provisions of the terms of the loan agreements, indentures and other agreements we may enter into from time to time.

If we liquidate or dissolve our business, the holders of common stock will share ratably in all assets available for distribution to stockholders after our creditors are paid in full and the holders of all series of our outstanding preferred stock, if any, receive their liquidation preferences in full.

The common stock has no preemptive rights and is not convertible or redeemable or entitled to the benefits of any sinking or repurchase fund. All issued and outstanding shares of common stock are fully paid and nonassessable. Any shares of common stock we may offer and sell under this prospectus will also be fully paid and nonassessable.

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Our outstanding shares of the common stock are listed on the New York Stock Exchange and trade under the symbol “MDR.” Any additional shares of common stock we may offer and sell under this prospectus will also be listed on the New York Stock Exchange.

The transfer agent and registrar for the common stock is Computershare Trust Company, N.A.

Preferred Stock

At the direction of our board of directors, without any action by the holders of our common stock, we may issue one or more series of preferred stock from time to time. Our board of directors can determine the number of shares of each series of preferred stock and, subject to some limitations our articles of incorporation set forth, the voting powers, designations, preferences and relative, participating, optional or other special rights, and the qualifications, limitations or restrictions applicable to any of those rights, including dividend rights, conversion or exchange rights, terms of redemption and liquidation preferences, of each series.

The prospectus supplement relating to any series of preferred stock we offer will include specific terms relating to the offering. These terms will include some or all of the following:

Any preferred stock we offer and sell under this prospectus will be fully paid and nonassessable.

The registration statement will include the certificate of designation as an exhibit or will incorporate the certificate of designation by reference. You should read that document for provisions that may be important to you.

The existence of undesignated preferred stock may enable our board of directors to render more difficult or to discourage an attempt to obtain control of us by means of a tender offer, proxy contest, merger or otherwise, and thereby to protect the continuity of our management. The issuance of shares of preferred stock may adversely affect the rights of the holders of common stock. For example, any preferred stock issued may rank prior to the common stock as to dividend rights, liquidation preference or both, may have full or limited voting rights and may be convertible into shares of common stock. As a result, the issuance of shares of preferred stock may discourage bids for common stock or may otherwise adversely affect the market price of the common stock or any existing preferred stock.

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Limitation on Directors’ Liability

Our articles of incorporation limit the liability of the members of our board of directors by providing that no director will be personally liable to us or our stockholders for monetary damages for any breach of the director’s fiduciary duty as a director, except for liability:

This provision could have the effect of reducing the likelihood of litigation against our directors and may discourage or deter our stockholders or management from bringing a lawsuit against our directors for breach of their duty of care, even though such an action, if successful, might otherwise have benefited us and our stockholders. Our by-laws provide indemnification to our officers and directors and other specified persons with respect to their conduct in various capacities.

Other Matters

Some of the provisions of our articles of incorporation and by-laws and Panamanian laws discussed below may have the effect, either alone or in combination, of making more difficult or discouraging a tender offer, proxy contest, merger or other takeover attempt that our board of directors opposes but that a stockholder might consider to be in its best interest.

Action by Written Consent

Under Panamanian Law, our stockholders may act by written consent without a meeting. However, any such consent must be either: (1) signed by all our stockholders or their respective representatives or proxies; or (2) signed by the holders of at least a majority of our outstanding shares of capital stock entitled to vote (or, in the case of an amendment to the provisions of our articles of incorporation described below relating to business combination transactions or the number, election and classification of directors, the holders of at least two-thirds of our outstanding shares of capital stock entitled to vote) or their respective representatives or proxies, provided that written waivers of a meeting are obtained by all stockholders who have not signed the written consent (which waivers may be obtained after the consents have been obtained). The practical effect of these provisions is that our stockholders cannot take action by written consent without unanimous concurrence by the stockholders in the action to be taken.

Business Combination Transactions Requiring More Than a Majority Vote

Under our articles of incorporation, whenever applicable law requires the vote or consent of our stockholders to authorize or approve a sale, lease or exchange of all or substantially all our property or assets or to adopt or approve an agreement of merger or consolidation of our company with or into any other corporation or to merge any other corporation into our company, the vote of at least two-thirds of our outstanding capital stock entitled to vote on that transaction is required for any such authorization, adoption or approval.

The super-majority requirement described above could:

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Filling Vacancies on our Board of Directors

Although members of our board of directors may be removed by a majority vote of our stockholders entitled to vote in the election of directors and actually voting on the matter, our articles of incorporation provide that any vacancies will be filled only by the affirmative vote of a majority of our remaining directors, even if less than a quorum. Therefore, without an amendment to our articles of incorporation, our board of directors could prevent any stockholder from removing directors or enlarging our board of directors and filling the vacancies with that stockholder’s own nominees.

Stockholder Board Nominations and Other Proposals

Our by-laws establish an advance-notice procedure for stockholders to make nominations of candidates for election as directors or to bring other business before a meeting of our stockholders. Our by-laws provide that, at any meeting of our stockholders, only such business may be conducted as shall have been brought before the meeting by or at the direction of our board of directors or by a stockholder who has given timely written notice meeting the requirements we describe below and who is a stockholder of record as of the time such stockholder gives that notice and will be entitled to vote at the meeting.

Under these provisions, for notice of stockholder director nominations or proposals to be made at an annual meeting to be timely, the notice must generally be received by us:

Under the by-laws, a stockholder’s notice to us proposing to nominate an individual for election as a director or relating to the conduct of business other than the nomination of directors at a meeting must contain specified information, including:

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The chairman of the meeting may refuse to permit any business to be brought before a meeting by a stockholder if that business was not brought before the meeting in compliance with the advance-notice provisions.

The advance-notice procedure may have the effect of precluding a contest for the election of directors or the consideration of stockholder proposals if the proper procedures are not followed, and of discouraging or deterring a third party from conducting a solicitation of proxies to elect its own slate of directors or to approve its own proposal, without regard to whether consideration of those nominees or proposals might be harmful or beneficial to our company and our stockholders.

Amendments to Articles of Incorporation and By-Laws

An amendment to our articles of incorporation generally requires the approval of the holders of a majority of our outstanding capital stock entitled to vote and actually voting on the amendment. However, the affirmative vote of two-thirds of our outstanding capital stock entitled to vote is required to amend, alter, change or repeal the provisions of our articles of incorporation regarding:

Our board of directors may amend, alter or repeal our by-laws and adopt new by-laws. In addition to requiring compliance with the advance-notice provisions described above, our by-laws provide that the vote of the holders of at least two-thirds of the voting power of the then outstanding shares of our capital stock entitled to vote is required for stockholders to amend, alter or repeal certain provisions of our by-laws relating to the powers and composition of our board of directors.

Panamanian Regulation of Acquisitions of Control

We are registered with the Panamanian National Securities Commission (the “PNSC”) and, as a result, we are subject to Decree No. 45 of December 5, 1977, of the Republic of Panama, as amended (the “Decree”). The Decree imposes certain restrictions on offers to acquire voting securities of a company registered with the PNSC if, following such an acquisition, the acquiror would own directly or indirectly more than 5% of the outstanding voting securities (or securities convertible into voting securities) of such company, with a market value of at least five million Balboas (approximately $5.0 million). Under the Decree, any such offeror would be required to provide McDermott with a declaration stating, among other things, the identity and background of the offeror, the source and amount of funds to be used in the proposed transaction and the offeror’s plans with respect to McDermott. In that event, the PNSC may, at our request, hold a public hearing as to the adequacy of the disclosure provided by the offeror. Following such a hearing, the PNSC would either determine that full and fair disclosure had been provided and that the offeror had complied with the Decree or prohibit the offeror from proceeding with the offer until it has furnished the required information and fully complied with the Decree. Under the Decree, such a proposed transaction cannot be consummated until 45 days after the delivery of the required declaration prepared or supplemented in a complete and accurate manner, and our board of directors may, in its discretion, within 15 days of receiving a complete and accurate declaration, elect to submit the transaction to a vote of our stockholders. In that case, the transaction could not proceed until approved by the holders of at least two-thirds of the voting power of the shares entitled to vote at a meeting held within 30 days of the date it is called. If such a vote is obtained, the shares held by the offeror would be required to be voted in the same proportion as all other shares that are voted in favor of or against the offer. If the stockholders approved the transaction, it would have to be consummated within 60 days following the date of that approval. The Decree provides for a civil right of action by stockholders against an offeror who does not comply with the provisions of the Decree. It also provides that certain persons, including brokers and other intermediaries who participate with the offeror in a transaction that violates the Decree, may be jointly and severally liable with the offeror for damages that arise from a violation of the Decree. We have a long-standing practice of not requiring a

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declaration under the Decree from passive investors who do not express any intent to exercise influence or control over our company and who remain as passive investors, so long as they timely file appropriate information on Schedule 13D or Schedule 13G under the Securities Exchange Act of 1934. This practice is consistent with advice we have received from our Panamanian counsel to the effect that our Board of Directors may waive the protection afforded by the Decree and not require declarations from passive investors who invest in our common stock with no intent to exercise influence or control over our company.

We believe these provisions protect our stockholders from coercive or otherwise unfair takeover tactics by requiring potential acquirors to negotiate with our board of directors and by providing our board of directors with more time to assess any acquisition proposal, and are not intended to make our company immune from takeovers. However, these provisions apply even if the offer may be considered beneficial by some stockholders and could delay or prevent an acquisition that our board of directors determines is not in the best interests of our company and our stockholders.

Description of Warrants

We may issue warrants to purchase debt securities, common stock, preferred stock or other securities. We may issue warrants independently or together with other securities. Warrants issued with other securities may be attached to or separate from those other securities. If we issue warrants, we will do so under one or more warrant agreements between us and a warrant agent that we will name in the prospectus supplement.

If we offer any warrants, we will file the forms of warrant certificate and warrant agreement with the SEC, and you should read those documents for provisions that may be important to you.

The prospectus supplement relating to any warrants being offered will include specific terms relating to the offering. These terms will include some or all of the following:

Warrant certificates will be exchangeable for new warrant certificates of different denominations at the office indicated in the prospectus supplement. Prior to the exercise of their warrants, holders of warrants will not have any of the rights of holders of the securities subject to the warrants.

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Modifications

We may amend the warrant agreements and the warrants without the consent of the holders of the warrants to cure any ambiguity, to cure, correct or supplement any defective or inconsistent provision, or in any other manner that will not materially and adversely affect the interests of holders of outstanding warrants.

We may also modify or amend various other terms of the warrant agreements and the warrants with the consent of the holders of not less than a majority in number of the then outstanding unexercised warrants affected. Without the consent of the holders affected, however, no modification or amendment may:

Enforceability of Rights

The warrant agent will act solely as our agent and will not assume any agency or trust obligation or relationship for or with any holder or beneficial owner of warrants. The warrant agent will not have any duty or responsibility if we default under the warrant agreements or the warrant certificates. A warrant holder may, without the consent of the warrant agent, enforce by appropriate legal action on its own behalf the holder’s right to exercise the holder’s warrants.

Description of Stock Purchase Contracts

and Stock Purchase Units

We may issue stock purchase contracts, including contracts obligating holders to purchase from us, and obligating us to sell to the holders, a specified number of shares of common stock at a future date or dates. We may fix the price per share of common stock and the number of shares of common stock at the time the stock purchase contracts are issued or by reference to a specific formula set forth in the stock purchase contracts. We may issue the stock purchase contracts separately or as part of units, which we refer to as “stock purchase units,” consisting of a stock purchase contract and our debt securities or debt obligations of third parties, including U.S. treasury securities, which may secure the holders’ obligations to purchase the common stock under the stock purchase contracts. The stock purchase contracts may require holders to secure their obligations under the stock purchase contracts in a specified manner. The stock purchase contracts also may require us to make periodic payments to the holders of the stock purchase units or vice versa, and such payments may be unsecured or refunded on some basis.

The applicable prospectus supplement will describe the terms of the stock purchase contracts or stock purchase units. The description in the prospectus supplement will not necessarily be complete, and reference will be made to the stock purchase contracts and, if applicable, collateral or depositary arrangements relating to the stock purchase contracts or stock purchase units. The applicable prospectus supplement will also describe material U.S. federal income tax considerations applicable to the stock purchase units and the stock purchase contracts.

Plan of Distribution

We may sell the securities in and outside the United States through underwriters or dealers, directly to purchasers or through agents, or through a combination of any such methods of sale.

Sale Through Underwriters or Dealers

If we use underwriters in the sale of the offered securities, the underwriters will acquire the securities for their own account. The underwriters may resell the securities from time to time in one or more transactions,

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including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Underwriters may offer securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. Unless we inform you otherwise in the prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to several conditions, and the underwriters will be obligated to purchase all the offered securities if they purchase any of them. The underwriters may change from time to time any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers.

During and after an offering through underwriters, the underwriters may purchase and sell the securities in the open market. These transactions may include overallotment and stabilizing transactions and purchases to cover syndicate short positions created in connection with the offering. The underwriters may also impose a penalty bid, whereby selling concessions allowed to syndicate members or other broker-dealers for the offered securities sold for their account may be reclaimed by the syndicate if such offered securities are repurchased by the syndicate in stabilizing or covering transactions. These activities may stabilize, maintain or otherwise affect the market price of the offered securities, which may be higher than the price that might otherwise prevail in the open market. If commenced, these activities may be discontinued at any time.

If we use dealers in the sale of securities, we will sell the securities to them as principals. They may then resell those securities to the public at varying prices determined by the dealers at the time of resale. The dealers participating in any sale of the securities may be deemed to be underwriters within the meaning of the Securities Act of 1933, as amended (the “Securities Act”), with respect to any sale of those securities. We will include in the prospectus supplement the names of the underwriters, dealers or agents, as well as any commissions payable by us to such underwriters, dealers or agents, and the terms of the transaction.

Direct Sales and Sales Through Agents

We may sell the securities directly. In that event, no underwriters or agents would be involved. We may also sell the securities through agents we designate from time to time. In the prospectus supplement, we will name any agent involved in the offer or sale of the offered securities, and we will describe any commissions payable by us to the agent. Unless we inform you otherwise in the prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those securities. We will describe the terms of any such sales in the prospectus supplement.

Delayed Delivery Contracts

If we so indicate in the prospectus supplement, we may authorize agents, underwriters or dealers to solicit offers from various types of institutions to purchase securities from us at the public offering price under delayed delivery contracts. These contracts would provide for payment and delivery on a specified date in the future. The contracts would be subject only to those conditions the prospectus supplement describes. The prospectus supplement will describe the commission payable for solicitation of those contracts.

General Information

We may have agreements with the agents, dealers and underwriters to indemnify them against civil liabilities, including liabilities under the Securities Act, or to contribute with respect to payments that the agents, dealers or underwriters may be required to make. Agents, dealers and underwriters may be customers of, engage in transactions with or perform services for us in the ordinary course of their businesses.

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Legal Matters

Baker Botts L.L.P., Houston, Texas, our outside counsel, will issue an opinion about the legality of any securities we offer through this prospectus. Arias, Fabrega and Fabrega, our Panamanian counsel, will pass upon some matters for us relating to Panamanian law. Any underwriters will be advised about issues relating to any offering by their own legal counsel.

Experts

The consolidated financial statements, incorporated in this prospectus by reference from the Company’s Current Report on Form 8-K filed on July 31, 2018, and the effectiveness of McDermott International, Inc.’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports, which are incorporated herein by reference. Such consolidated financial statements have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

The consolidated financial statements of CB&I appearing in CB&I’s Annual Report (Form 10-K) for the year ended December 31, 2017, and the effectiveness of CB&I’s internal control over financial reporting as of December 31, 2017 have been audited by Ernst & Young LLP, an independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference to the Company’s Current Report on Form 8-K filed on May 11, 2018. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The following table sets forth expenses payable by McDermott in connection with the issuance and distribution of the securities being registered. All the amounts shown are estimates.

Item 15. Indemnification of Directors and Officers.

Panama Law

Under the Civil Code of the Republic of Panama, an agent is indemnified against liability incurred in acting without fault or imprudence on behalf of the agent’s principal. This provision would apply to indemnify directors and officers against liability incurred in connection with the performance of their duties. According to Arias, Fabrega and Fabrega, our Panamanian counsel, Panamanian law does not recognize the concept of actions brought by stockholders in the right of the corporation against directors or officers (i.e., derivative actions). Directors can be held liable to the corporation or stockholders only on demand made by resolution of the stockholders, which McDermott believes is difficult to achieve in a public company.

Articles of Incorporation and By-Laws

Article VI of our by-laws provides for the indemnification of officers and directors as follows:

ARTICLE VI

Indemnification

Section 1. Each person (and the heirs, executors and administrators of such person) who is or was a director and/or officer of the Company, whether elected or appointed (each such person being an “Indemnitee”), shall in accordance with Section 2 of this Article VI be indemnified and held harmless by the Company to the fullest extent permitted by applicable law in effect on the date of amendment and restatement of these By-Laws, and to such greater extent as applicable law may thereafter permit, including against any and all losses, liabilities, costs, damages and reasonable expenses that may be paid or incurred by such Indemnitee in connection with or

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resulting from any actual or threatened claim, action, suit or proceeding (whether brought by or in the right of the Company or otherwise), civil, criminal, administrative or investigative, or in connection with an appeal relating thereto, in which such Indemnitee may become involved, as a party or otherwise, by reason of such Indemnitee being or having been a director or officer of the Company or, if such Indemnitee shall be serving or shall have served in such capacity at the request of the Company, as a director, officer, employee or agent of another corporation or any partnership, joint venture, trust or other entity whether or not such Indemnitee continues to be such at the time such liability or expense shall have been paid or incurred, provided such Indemnitee acted, in good faith, in a manner he or she reasonably believed to be in or not opposed to the best interest of the Company and in addition, in criminal actions or proceedings, had no reasonable cause to believe that his or her conduct was unlawful. As used in this ARTICLE VI, the terms, “liability” and “expense” shall include, but shall not be limited to, counsel fees and disbursements and amounts of judgments, fines or penalties against, and amounts paid in settlement by, such director or officer. The termination of any actual or threatened claim, action, suit or proceeding, civil, criminal, administrative, or investigative, by judgment, settlement (whether with or without court approval), conviction or upon a plea of guilty or nolo contendere, or its equivalent, shall not create a presumption that such Indemnitee did not meet the standards of conduct set forth in this Section 1.

Section 2. Every Indemnitee shall be entitled to indemnification under Section 1 of this ARTICLE VI with respect to any claim, action, suit or proceeding of the character described in such Section 1 in which he or she may become in any way involved as set forth in such Section 1, if (i) he or she has been wholly successful on the merits or otherwise in respect thereof, or (ii) the Board of Directors acting by a majority vote of a quorum consisting of directors who are not parties to (or who have been wholly successful with respect to) such claim, action, suit or proceeding, finds that such Indemnitee has met the standards of conduct set forth in such Section 1 with respect thereto, or (iii) a court determines that he or she has met such standards with respect thereto, or (iv) independent legal counsel (who may be the regular counsel of the Company) deliver to the Company their written advice that, in their opinion, he or she has met such standards with respect thereto.

Section 3. For every such Indemnitee who has become or been threatened to become, a party to any actual or threatened claim, action, suit or proceeding of any kind that might give right to such Indemnitee to indemnification under Section 1 of this Article VI (each, a “Matter”), the Company will advance all expenses reasonably incurred by or on behalf of that Indemnitee in connection with that Matter, provided that that Indemnitee shall have delivered an undertaking by or on behalf of that person to repay to the Company any expenses so advanced if it is ultimately determined that that Indemnitee is not entitled to be indemnified by the Company under that Section 1 in respect of those expenses. The Company will accept any such undertaking of any such Indemnitee without regard to the financial ability of such Indemnitee to make such payment. Notwithstanding the foregoing, this Section 3 will not require the Company to advance expenses with respect to any Matter initiated by or on behalf of any such Indemnitee against the Company or any of its subsidiaries, whether as an initial action or by counter or similar claim, without the prior approval of the Board of Directors. The provisions of this Section 3 shall inure to the benefit of the heirs, executors and administrators of any person entitled to the benefits of this Section 3. No amendment to this Section 3, directly or by amendment to any other provision of these By-Laws, shall have any retroactive effect with respect to any Matter arising from or based on any act or omission to act by any person which occurs prior to the effectiveness of that amendment.

Section 4. The Company, by adoption of a resolution of the Board of Directors, may indemnify and advance expenses to a person who is an employee, agent or fiduciary of the Company including any such person who is or was serving at the request of the Company as a director, officer, employee, agent or fiduciary of any other corporation or any partnership, joint venture, trust or other entity to the same extent and subject to the same conditions under which it may indemnity and advance expenses to an Indemnitee under this ARTICLE VI.

Section 5. The rights of indemnification under this ARTICLE VI shall be in addition to any rights to which any such Indemnitee may otherwise be entitled by contract or as a matter of law.

Section 6. If any provision or provisions of this ARTICLE VI shall be held to be invalid, illegal or unenforceable for any reason whatsoever, the validity, legality and enforceability of the remaining provisions

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shall not in any way be affected or impaired thereby; and, to the fullest extent possible, the provisions of this ARTICLE VI shall be construed so as to give effect to the intent manifested by the provision held invalid, illegal or unenforceable.

Additionally, our articles of incorporation contain a provision that eliminates the personal liability of each director to the Company or its stockholders for monetary damages for breach of the director’s fiduciary duty as a director, except for liability for (1) any breach of the director’s duty of loyalty to the Company or its stockholders, (2) acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (3) unlawful payment of dividends or an unlawful stock purchase or redemption or (4) any transaction from which that director derived an improper personal benefit. As a result, stockholders may be unable to recover monetary damages against directors for negligent or grossly negligent acts or omissions in violation of their duty of care.

Indemnification Agreements and Insurance

Agreements McDermott may enter into with underwriters, dealers and agents who participate in the distribution of securities of McDermott may contain provisions relating to the indemnification of McDermott’s officers and directors.

McDermott also maintains directors’ and officers’ liability insurance for its directors and officers that protects them from certain losses arising from claims or charges made against them in their capacities as directors or officers of McDermott.

McDermott maintains insurance policies under which its directors and officers are insured, within the limits and subject to the limitations of the policies, against certain expenses in connection with the defense of actions, suits or proceedings, and certain liabilities which might be imposed as a result of such actions, suits or proceedings, to which they are parties by reason of being or having been such directors or officers.

Item 16. Exhibits.*

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Item 17. Undertakings

(a) The undersigned Registrant hereby undertakes:

provided, however, that paragraphs (1)(i), (1)(ii) and (1)(iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

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The undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to the registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, McDermott International, Inc. certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of London, England, on September 27, 2018.

POWER OF ATTORNEY

Each person whose signature appears below appoints David Dickson, Stuart Spence and John Freeman, and each of them, severally, as his or her true and lawful attorney or attorneys-in-fact and agent or agents, each of whom shall be authorized to act with or without the other, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead in his or her capacity as a director or officer or both, as the case may be, of McDermott International, Inc., to sign any and all amendments (including post-effective amendments) to this Registration Statement, and all documents or instruments necessary or appropriate to enable McDermott International, Inc. to comply with the Securities Act of 1933, as amended, and to file the same with the Securities and Exchange Commission, with full power and authority to each of said attorneys-in-fact and agents to do and perform in the name and on behalf of each such director or officer, or both, as the case may be, each and every act whatsoever that is necessary, appropriate or advisable in connection with any or all of the above-described matters and to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them or their substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities indicated on September 27, 2018.