Description of securities

Exhibit 4.2

DRIL-QUIP, INC.

DESCRIPTION OF SECURITIES

DESCRIPTION OF CAPITAL STOCK

The common stock of Dril-Quip, Inc. (“we,” “us” and “our”) is listed on the New York Stock Exchange (the “NYSE”) under the symbol “DRQ.” Our authorized capital stock consists of 100,000,000 shares of common stock, par value $0.01 per share, and 10,000,000 shares of preferred stock, par value $0.01 per share.

The following summary of the material terms of our capital stock, Restated Certificate of Incorporation (the “certificate of incorporation”) and Amended and Restated Bylaws (the “bylaws”) does not purport to be complete and is qualified in its entirety by reference to the provisions of applicable law and to our certificate of incorporation and bylaws.

Common Stock

Each share of common stock entitles the holder to one vote on all matters on which holders are permitted to vote, including the election of directors. There are no cumulative voting rights. Accordingly, holders of a majority of the total votes entitled to vote in an election of directors will be able to elect all of the directors standing for election. Subject to preferences that may be applicable to any outstanding preferred stock, the holders of the common stock will share equally on a per share basis any dividends when, as and if declared by the board of directors out of funds legally available for that purpose. If we are liquidated, dissolved or wound up, the holders of our common stock will be entitled to a ratable share of any distribution to stockholders, after satisfaction of all of our liabilities and of the prior rights of any outstanding class of our preferred stock. Our common stock has no preemptive or conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to our common stock. All outstanding shares of our common stock are fully paid and nonassessable.

Preferred Stock

Under the terms of our certificate of incorporation, our board of directors has the authority, without stockholder approval, to issue shares of preferred stock from time to time in one or more series, and to fix the number of shares and terms of each such series. The board may determine the designation and other terms of each series, including the following:

The issuance of preferred stock, while providing us with flexibility in connection with possible acquisitions and other transactions, could adversely affect the voting power of holders of our common stock. It could also affect the likelihood that holders of our common stock will receive dividend payments and payments upon liquidation.

The issuance of shares of preferred stock, or the issuance of rights to purchase shares of preferred stock, could be used to discourage an attempt to obtain control of our company. For example, if, in the exercise of its fiduciary obligations, our board of directors were to determine that a takeover proposal was not in the best interest of our stockholders, the board could authorize the issuance of a series of preferred stock containing class voting rights that would enable the holder or holders of this series to prevent a change of control transaction or make it more difficult. Alternatively, a change of control transaction deemed by the board to be in the best interest of our stockholders could be facilitated by issuing a series of preferred stock having sufficient voting rights to provide a required percentage vote of the stockholders.

Anti-Takeover Effects of Provisions of Our Certificate of Incorporation and Our Bylaws

Certain provisions of our certificate of incorporation and our bylaws, as described below, could have the effect of delaying, deterring or preventing another party from acquiring or seeking to acquire control of us. These provisions are intended to discourage certain types of coercive takeover practices and inadequate takeover bids and to encourage anyone seeking to acquire control of us to negotiate first with our board of directors. However, these provisions may also delay, deter or prevent a change in control or other takeover of Dril-Quip, Inc. that our stockholders might consider to be in their best interests, including transactions that might result in a premium being paid over the market price of our common stock and also may limit the price that investors are willing to pay in the future for our common stock. These provisions may also have the effect of preventing changes in our management. We believe that the benefits of increased protection give us the potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us, and that the benefits of this increased protection outweigh the disadvantages of discouraging those proposals, because negotiation of those proposals could result in an improvement of their terms.

Election and Removal of Directors

Our board of directors must consist of between three and 12 directors. The exact number of directors is fixed from time to time by resolution of the board. Our board of directors is divided into three classes serving staggered three-year terms, with only one class being elected each year by our stockholders. At each annual meeting of stockholders, directors will be elected to succeed the class of directors whose terms have expired. This system of electing and removing directors may discourage a third party from making a tender offer or otherwise attempting to obtain control of us because it generally makes it more difficult for stockholders to replace a majority of the directors. In addition, no director may be removed except for cause, and directors may be removed for cause only by the affirmative vote of shares representing a majority of the shares then entitled to vote at an election of directors. Any vacancy occurring on the board of directors and any newly created directorship may only be filled by the affirmative vote of a majority of the remaining directors in office.

Stockholder Meetings

Our certificate of incorporation and our bylaws provide that special meetings of our stockholders may be called only by the chairman of our board of directors, the chief executive officer, the president or the board pursuant to a resolution approved by the affirmative vote of a majority of the entire board of directors.

Stockholder Action by Written Consent

Our certificate of incorporation provides that any action required or permitted to be taken by the stockholders of our company must be effected at an annual or special meeting of stockholders and may not be effected by any consent in writing by such stockholders.

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Amendment of Bylaws

Our bylaws may generally be altered, amended or repealed, and new bylaws may be adopted, by:

Other Limitations on Stockholder Actions

Our bylaws also impose some procedural requirements on stockholders who wish to:

Under these procedural requirements, in order to bring a proposal before a meeting of stockholders, a stockholder must deliver timely notice of a proposal pertaining to a proper subject for presentation at the meeting to our corporate secretary along with the information required under our bylaws, including the following:

A stockholder providing notice of business proposed to be brought before a meeting shall further update and supplement such notice, if necessary, so that the information provided or required to be provided in such notice shall be true and correct as of the record date for the meeting and as of the date that is ten business days prior to the meeting or any adjournment or postponement thereof.

To be timely, a stockholder’s notice must generally be delivered to, or mailed and received at, our principal executive offices:

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In order to submit a nomination for our board of directors, a stockholder must also submit any information with respect to the nominee that we would be required to include in a proxy statement, as well as some other information. If a stockholder fails to follow the required procedures, the stockholder’s proposal or nominee will be ineligible and will not be voted on by our stockholders.

Limitation on Liability of Directors

Our certificate of incorporation provides that no director will be personally liable to us or our stockholders for monetary damages for breach of fiduciary duties as a director, except as required by applicable law, as in effect from time to time. Currently, Delaware law requires that liability be imposed for the following:

Our bylaws provide that, to the fullest extent permitted by law, we will indemnify any officer or director of our company against all damages, claims and liabilities arising out of the fact that the person is or was our director or officer, or served any other enterprise at our request as a director, officer, employee, agent or fiduciary. We will reimburse the expenses, including attorneys’ fees, incurred by a person indemnified by this provision when we receive an undertaking to repay such amounts if it is ultimately determined that the person is not entitled to be indemnified by us. Amending this provision will not reduce our indemnification obligations relating to actions taken before an amendment.

Transactions and Corporate Opportunities

In order to approve certain transactions involving related persons, our certificate of incorporation requires the affirmative vote of the holders of (1) not less than 80% of the then outstanding voting stock held by stockholders voting together as a single class and (2) not less than 66 2/3% of the then outstanding voting stock not beneficially owned, directly or indirectly, by the related person. These transactions include:

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A related person is a person or entity who or which (1) is the beneficial owner of 10% or more of the aggregate voting power of all of our outstanding stock; (2) is one of our affiliates and at any time within the two-year period immediately prior to the date in question was the beneficial owner of 10% or more of the aggregate voting power of all of our outstanding stock; or (3) is an assignee of or has otherwise succeeded to any shares of our stock that were at any time within the two-year period immediately prior to the date in question beneficially owned by any related person, if such assignment or succession shall have occurred in the course of a privately negotiated transaction rather than an open market transaction.

These voting requirements do not apply, however, to a business combination if:

Anti-Takeover Effects of Delaware Law

We are a Delaware corporation and are subject to Section 203 of the DGCL. Section 203 provides that we may not engage in a broad range of “business combinations” with any “interested stockholder” for a three-year period following the time that the person became an interested stockholder unless:

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Generally, a business combination includes a merger, consolidation, asset or stock sale or other transaction resulting in a financial benefit to the interested stockholder. Subject to certain exceptions, an interested stockholder is a person who, together with that person’s affiliates and associates, owns, or within the previous three years owned, 15% or more of our voting stock. Under Section 203, the restrictions described above also do not apply to specific business combinations proposed by an interested stockholder following the announcement or notification of designated extraordinary transactions involving the corporation and a person who had not been an interested stockholder during the previous three years or who became an interested stockholder with the approval of a majority of the corporation’s directors, if such extraordinary transaction is approved or not opposed by a majority of the directors who were directors prior to any person becoming an interested stockholder during the previous three years or were recommended for election or elected to succeed such directors by a majority of such directors.

Section 203 could prohibit or delay mergers or other takeover or change in control attempts with respect to us and, accordingly, may discourage attempts to acquire us.

Transfer Agent and Registrar

Computershare Shareowner Services LLC is the transfer agent and registrar for our common stock.

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