NEWP Newport Corp.

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
To Be Held on April 27, 2016

To the Stockholders of Newport Corporation:

        NOTICE IS HEREBY GIVEN that a special meeting of stockholders of Newport Corporation (" Newport ") will be held at our corporate headquarters, located at 1791 Deere Avenue, Irvine, California 92606 on April 27, 2016 at 9:00 a.m., local time, to consider and act on the following proposals at the special meeting:

        1.     To adopt and approve the Agreement and Plan of Merger, dated as of February 22, 2016 (the " Merger Agreement "), by and among Newport, MKS Instruments, Inc., a Massachusetts corporation (" Parent "), and PSI Equipment, Inc., a Nevada corporation and a newly formed, wholly owned subsidiary of Parent (" Merger Sub "), and the transactions contemplated thereby, including the merger of Merger Sub with and into Newport (the " Merger "), with Newport surviving the Merger as a wholly owned subsidiary of Parent (the " Merger Proposal "). Pursuant to the terms of the Merger Agreement, each share of Newport common stock issued and outstanding immediately prior to the effective time of the Merger (other than shares held in the treasury of Newport or shares owned, directly or indirectly, by Parent, Merger Sub or any wholly owned subsidiary of Newport, Parent or Merger Sub immediately prior to the effective time of the Merger) will be cancelled and converted into the right to receive $23.00 in cash, without interest and subject to deduction for any required withholding tax;

        2.     To approve the postponement or adjournment of the special meeting to solicit additional proxies if there are not sufficient votes to approve the Merger Proposal, if deemed necessary or appropriate by the board of directors of Newport (the " Adjournment Proposal "); and

        3.     To approve on a non-binding, advisory basis, certain compensation that will or may become payable to our named executive officers that is based on or otherwise relates to the Merger (the " Merger-Related Named Executive Officer Compensation Proposal "), as disclosed pursuant to Item 402(t) of Regulation S-K in " The Merger—Interests of Our Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to Our Named Executive Officers " beginning on page 60 of the accompanying proxy statement.

        No other business may be transacted at the special meeting.

        The accompanying proxy statement and its annexes, including all documents incorporated by reference into the accompanying proxy statement, more fully describe these items of business. We urge you to read this information carefully.

         The board of directors of Newport unanimously recommends that you vote (1) "FOR" the Merger Proposal; (2) "FOR" the Adjournment Proposal; and (3) "FOR" the Merger-Related Named Executive Officer Compensation Proposal. The approval by Newport stockholders of the Merger Proposal is required to complete the Merger described in the accompanying proxy statement.

        Only holders of record of shares of our common stock at the close of business on March 21, 2016, the record date for the special meeting, are entitled to notice of and to vote at the special meeting and any adjournments or postponements of the special meeting. If you have any questions concerning the Merger, the special meeting or the accompanying proxy statement, need help voting your shares of Newport common stock, or would like additional copies, without charge, of the enclosed proxy

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statement or proxy card, please contact Newport's proxy solicitor, MacKenzie Partners, Inc., using the information below:

Call Collect: (212) 929-5500
Toll Free: (800) 322-2885
Email to: proxy@mackenziepartners.com
Address: 105 Madison Avenue, New York, New York 10016

         Your vote is very important.     It is important that your shares be represented and voted whether or not you plan to attend the special meeting in person. You may vote by completing and mailing the proxy card enclosed with the proxy statement, or you may grant your proxy electronically via the Internet or by telephone by following the instructions on the proxy card. Submitting a proxy over the Internet, by telephone or by mailing a proxy card will ensure your shares are represented at the special meeting. If your shares are held in "street name," which means your shares are held of record by a broker, bank or other nominee, you should instruct your broker, bank or other nominee how to vote your shares using the voting instruction form furnished by your broker, bank or other nominee. If you do not vote or do not instruct your broker, bank or other nominee how to vote, it will have the same effect as voting against the Merger Proposal.

Irvine, California
March 29, 2016

EVEN IF YOU PLAN TO ATTEND THE SPECIAL MEETING, PLEASE VOTE BY PROXY PRIOR TO THE SPECIAL MEETING. IF YOU CHOOSE TO VOTE BY MAIL, PLEASE DO SO PROMPTLY TO ENSURE YOUR PROXY ARRIVES IN SUFFICIENT TIME.

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QUESTIONS AND ANSWERS ABOUT THE MERGER
AND THE SPECIAL MEETING

         The following questions and answers briefly address some questions you may have regarding the special meeting and the proposed merger. These questions and answers may not address all questions that may be important to you as a stockholder of Newport Corporation. Please refer to the more detailed information contained elsewhere in this proxy statement, the annexes to this proxy statement and the documents referred to in this proxy statement. We encourage you to read this proxy statement, including the annexes, in its entirety because it explains the proposed merger, the documents related to the merger and other related matters. In this proxy statement, the terms "the Company," "we," "our," "ours," "us" and "Newport" refer to Newport Corporation. We refer to MKS Instruments, Inc. as "Parent" and PSI Equipment, Inc. as "Merger Sub."

Q:

Why am I receiving this proxy statement and proxy card?

A:

You are receiving this proxy statement and proxy card because, as of March 21, 2016, the record date for the determination of stockholders entitled to notice of and to vote at the special meeting (the " Record Date "), you owned shares of our common stock, par value $0.1167 per share (" Company Common Stock "). We have entered into the Agreement and Plan of Merger, dated as of February 22, 2016 (the " Merger Agreement "), by and among Newport, Parent, and Merger Sub. Pursuant to the Merger Agreement, subject to the adoption and approval of the Merger Agreement and the Merger (as defined below) by our stockholders and the satisfaction of other conditions to the completion of the transactions specified in the Merger Agreement, Merger Sub will merge with and into Newport (the " Merger "), with Newport surviving the Merger as a wholly owned subsidiary of Parent, and Company Common Stock will be delisted from NASDAQ Global Select Market (" NASDAQ "). A copy of the Merger Agreement is attached to this proxy statement as Annex A.

In order to complete the Merger, our stockholders must vote to approve the Merger Proposal (as defined below). We will hold a special meeting of our stockholders to obtain this approval. Our board of directors (the " Company Board ") is providing this proxy statement to give you information for use in determining how to vote on the proposals submitted to the stockholders at the special meeting. You should read this proxy statement and the annexes carefully. The enclosed proxy card and voting instructions allow you, as a Newport stockholder, to have your shares voted at the special meeting without attending the special meeting. Your proxy is being solicited by the Company Board.

Your vote is very important. If you do not vote or do not instruct your broker, bank or other nominee how to vote, it will have the same effect as voting "AGAINST" the Merger Proposal (as defined below). We encourage you to submit your proxy as soon as possible.

Q:

When and where is the special meeting?

A:

The special meeting of our stockholders will be held on April 27, 2016, at 1791 Deere Avenue, Irvine, California 92606, at 9:00 a.m. local time.

Q:

What will happen in the Merger?

A:

Merger Sub will be merged with and into the Company, and the separate corporate existence of Merger Sub will cease. The Company will survive the Merger as a wholly owned subsidiary of Parent, and Company Common Stock will be delisted from NASDAQ.

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Q:

As a holder of shares of Company Common Stock, what will I receive in the Merger?

A:

Upon the completion of the Merger, each share of Company Common Stock issued and outstanding immediately prior to the effective time of the Merger (other than shares held in the treasury of Newport, or shares owned, directly or indirectly, by Parent, Merger Sub or any wholly owned subsidiary of Newport, Parent or Merger Sub immediately prior to the effective time of the Merger (collectively, the " Excluded Shares ")), will be automatically cancelled and converted into the right to receive $23.00 in cash, without interest, and subject to deduction for any required withholding tax. For example, if you own 100 shares of Company Common Stock, you will be entitled to receive $2,300.00 in cash, without interest, and subject to deduction for any required withholding tax, in exchange for your shares. Any withheld amounts will be treated for all purposes as having been paid to the holder of Company Common Stock in respect of whose shares the withholding was made.

Q:

What will holders of Newport equity awards receive in the Merger?

A:

Restricted Stock Units.     At the effective time of the Merger, each restricted stock unit (each, a " Company RSU ") granted under any stock option or equity compensation plan, arrangement or agreement of the Company (" Company Equity Plans ") that is outstanding immediately prior to the effective time of the Merger and as to which shares of Company Common Stock will not have been fully distributed in connection with the closing of the Merger will be assumed by Parent, and will continue to have and be subject to the same terms and conditions (including the same vesting conditions) as were in effect for such Company RSU immediately prior to the effective time of the Merger, except that such Company RSU will become an award for a number of shares of common stock, no par value, of Parent (" Parent Common Stock ") equal to the number of shares of Company Common Stock subject to such Company RSU multiplied by a fraction (the " Equity Award Exchange Ratio "), the numerator of which will be the merger consideration of $23.00 per share and the denominator of which will be the average of the volume weighted average price per share of Parent Common Stock on NASDAQ over the five consecutive trading days ending on the second complete trading day preceding the closing date for the Merger (with the result rounded down to the nearest whole share).

Stock Appreciation Rights.     At the effective time of the Merger, each stock appreciation right granted under a Company Equity Plan (each, a " Company SAR "), whether vested or unvested, that is outstanding immediately prior to the effective time of the Merger will be assumed by Parent, and will continue to have and be subject to the same terms and conditions (including vesting schedule) as were in effect for such Company SAR immediately prior to the effective time of the Merger, except that such Company SAR will become an award for a number of shares of Parent Common Stock equal to the number of shares of Company Common Stock subject to such Company SAR multiplied by the Equity Award Exchange Ratio (rounded down to the nearest whole share), with a per share base value equal to the per share base value for such Company SAR immediately prior to the effective time of the Merger, divided by the Equity Award Exchange Ratio (rounded up to the nearest whole cent).

Notwithstanding the above, the Merger Agreement provides that the treatment described above may be changed by agreement of the Company and Parent with respect to Company RSUs and Company SARs held by non-U.S. employees and/or non-employee directors of the Company. As permitted by the Merger Agreement, the Company intends to cause all Company RSUs held by non-employee directors of the Company to accelerate and vest in full and be settled immediately prior to the effective time of the Merger.

See the section entitled " The Merger Agreement—Treatment of Newport Equity Awards " beginning on page 68 of this proxy statement.

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Q:

When do you expect the Merger to be completed?

A:

We are working toward completing the Merger as quickly as possible and expect to complete the Merger in the second quarter of 2016. However, because there are certain conditions that must be met before completing the Merger, we cannot be certain of the timing of the completion of the Merger. See the section entitled " The Merger Agreement—Conditions to Completion of the Merger " beginning on page 85 of this proxy statement.

Q:

What are Newport stockholders being asked to vote on and why is this approval necessary?

A:

Newport stockholders are being asked to consider and vote on the following three proposals:

1.

To adopt and approve the Merger Agreement, a copy of which is attached as Annex A to this proxy statement, and the transactions contemplated thereby, including the Merger (the " Merger Proposal ");

2.

To approve the postponement or adjournment of the special meeting to solicit additional proxies if there are not sufficient votes to approve the Merger Proposal, if deemed necessary or appropriate by the Company Board (the " Adjournment Proposal "); and

3.

To approve on a non-binding, advisory basis, certain compensation that will or may become payable to our named executive officers that is based on or otherwise relates to the Merger (the " Merger-Related Named Executive Officer Compensation Proposal "), as disclosed pursuant to Item 402(t) of Regulation S-K in " The Merger—Interests of Our Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to Our Named Executive Officers " beginning on page 60 of this proxy statement.

Newport stockholder approval of the Merger Proposal is required for completion of the Merger. Newport stockholder approval of the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal are not required for completion of the Merger. No other matters are intended to be brought before the special meeting by Newport.

Q:

What do I need to do now?

A:

After carefully reading and considering the information contained in this proxy statement, please vote your shares of Company Common Stock as soon as possible so that your shares of Company Common Stock will be represented at the special meeting. Please follow the instructions set forth on the proxy card or on the voting instruction form provided by the record holder if your shares of Company Common Stock are held in "street name" through your broker, bank or other nominee.

Q:

How do I cast my vote?

A:

Before you vote, you should read this proxy statement, including its annexes, in its entirety and carefully consider how the Merger affects you.

If you were a holder of record of Company Common Stock on the Record Date, you may vote in person at the special meeting, by submitting a proxy for the special meeting by completing, signing, dating and returning the enclosed proxy card in the accompanying pre-addressed, postage paid envelope, or by granting a proxy electronically via the Internet or by telephone by following the instructions on the enclosed proxy card. Internet and telephone proxy submissions are available 24 hours a day, and if you use one of these methods, you do not need to return a proxy card. You must have the enclosed proxy card available, and follow the instructions on such proxy card, in order to grant a proxy over the Internet or telephone.

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If you sign, date and mail your proxy and do not indicate how you want to vote, your proxy will be voted " FOR " the Merger Proposal, " FOR " the Adjournment Proposal and " FOR " the Merger-Related Named Executive Officer Compensation Proposal.

If you hold your shares of Company Common Stock in "street name," which means your shares are held of record by a broker, bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares in accordance with the voting instructions provided by your broker, bank or other nominee. If you do not provide your broker, bank or other nominee with instructions on how to vote your shares, they will not be permitted to vote your shares. A "broker non-vote" occurs with respect to a particular proposal when a nominee holding shares for a beneficial owner returns a valid proxy but does not vote on such proposal because the nominee does not have discretionary voting authority with respect to such proposal and has not received instructions with respect to such proposal from the beneficial owner of the shares. Also, please note that if your shares are held in "street name" and you wish to vote at the special meeting in person, you must bring to the special meeting a legal proxy from the record holder of the shares (your broker, bank or other nominee) authorizing you to vote at the special meeting.

Q:

Who can vote or submit a proxy to vote and attend the special meeting?

A:

All holders of record of Company Common Stock as of the close of business on the Record Date are entitled to receive notice of and to attend and to vote or submit a proxy to vote at the special meeting. If your shares are held of record in an account at a brokerage firm, bank or other nominee, such broker, bank or other nominee is considered the holder of record of your shares and will forward the proxy notice and materials to you with a voting instruction form explaining how to vote your shares. If you want to attend the special meeting and your shares are held of record by a broker, bank or other nominee, then you must bring to the special meeting a legal proxy from the record holder of the shares (your broker, bank or other nominee) authorizing you to vote at the special meeting.

Q:

How does the Company Board recommend that I vote?

A:

The Company Board unanimously recommends that you vote:

•

" FOR " the Merger Proposal;

•

" FOR " the Adjournment Proposal; and

•

" FOR " the Merger-Related Named Executive Officer Compensation Proposal.

Q:

Why is the Company Board recommending that I vote "FOR" the Merger Proposal?

A:

After careful review and consideration, the Company Board, upon the unanimous recommendation of an independent committee of the Company Board, unanimously determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are fair to, and in the best interests of, the Company and its stockholders. After such consideration, the Company Board approved the Merger Agreement and authorized and approved the Merger upon the terms and conditions set forth in the Merger Agreement. In reaching its decision to approve the Merger Proposal and, subject to the terms and conditions of the Merger Agreement, to recommend the approval of the Merger Proposal, the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal by our stockholders, the Company Board consulted with our management, as well as our legal and financial advisors, and considered the terms of the proposed Merger Agreement. The Company Board also considered each of the items set forth under " The Merger—Recommendation of the Company Board; Our Reasons for the Merger " beginning on page 40 of this proxy statement.

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Q:

Do any of Newport's directors or executive officers have interests in the Merger that may differ from those of the stockholders?

A:

Yes. Our directors and executive officers have interests in the Merger that are different from, or in addition to, the interests of the stockholders. See the section entitled " The Merger—Interests of Our Directors and Executive Officers in the Merger " beginning on page 56 of this proxy statement. The members of the Company Board were aware of and considered these interests, among other matters, in evaluating the Merger Agreement and the Merger and in recommending that the stockholders vote to approve the Merger Proposal.

Q:

How does the per share merger consideration compare to the market price of Company Common Stock?

A:

The merger consideration of $23.00 per share of Company Common Stock represents a premium of (i) 57% compared to $14.69, our average closing price for the one-month period ended February 22, 2016, the last trading date prior to public announcement of the proposed Merger, (ii) 52% compared to $15.14, our average closing price for the six-month period ended as of such date, and (iii) 53% compared to the closing price of $15.04 on February 22, 2016, the last trading date prior to public announcement of the proposed Merger.

Q:

What vote of Newport stockholders is required to approve the Merger Proposal?

A:

As a condition of the Merger and assuming a quorum is present, approval of the Merger Proposal requires the affirmative vote of the holders of a majority of the outstanding shares of Company Common Stock entitled to vote. The obligations of the Company and Parent to complete the Merger are also subject to the satisfaction or waiver of several other conditions as set forth in the Merger Agreement. If you do not vote, or if you indicate on your proxy that you abstain from voting on the Merger Proposal, it will have the same effect as voting " AGAINST " the Merger Proposal. If your shares of Company Common Stock are held in "street name," which means your shares are held of record by a broker, bank or other nominee, and you fail to give voting instructions to your broker, bank or other nominee, it will have the same effect as voting "AGAINST" the Merger Proposal.

Q:

What vote of Newport stockholders is required to approve the Adjournment Proposal?

A:

The affirmative vote of a majority of the shares of Company Common Stock, present in person or represented by proxy at the special meeting and entitled to vote, is required to approve the Adjournment Proposal, whether or not a quorum is present. If you indicate on your proxy that you abstain from voting on the Adjournment Proposal, it will have the same effect as voting " AGAINST " the Adjournment Proposal. If you are a holder of record of Company Common Stock on the Record Date and do not vote, or if your shares of Company Common Stock are held in "street name," which means your shares are held of record by a broker, bank or other nominee, and you fail to give voting instructions to your broker, bank or other nominee with respect to the Adjournment Proposal, it will have no effect on the outcome of the Adjournment Proposal (unless you give voting instructions to your broker, bank, or other nominee with respect to at least one other proposal to be voted on at the special meeting, in which case your failure to give such voting instructions with respect to the Adjournment Proposal will have the same effect as voting " AGAINST " the Adjournment Proposal).

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Q:

Why am I being asked to approve the Merger-Related Named Executive Officer Compensation Proposal, on an advisory, non-binding basis?

A:

Pursuant to the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the " Dodd-Frank Act ") and rules adopted by the Securities and Exchange Commission (the " SEC "), we are required to provide our stockholders with the opportunity to vote to approve, on an advisory, non-binding basis, the compensation arrangements between the Company and its named executive officers that are based on or that otherwise relate to the Merger. Approval of these compensation arrangements is not a condition to completion of the Merger, and the vote with respect to this proposal is advisory only. Accordingly, the vote will not be binding on the Company or Parent, or their respective boards of directors or compensation committees.

Q:

What happens if the stockholders do not approve the Merger-Related Named Executive Officer Compensation Proposal at the special meeting?

A:

Approval of the Merger-Related Named Executive Officer Compensation Proposal is not a condition to the completion of the Merger. The vote with respect to the Merger-Related Named Executive Officer Compensation Proposal is an advisory vote and will not be binding on the Company or Parent, or their respective boards of directors or compensation committees. Further, the underlying arrangements are contractual in nature and not, by their terms, subject to stockholder approval. Accordingly, regardless of the outcome of the advisory vote, if the Merger is consummated, our named executive officers may become eligible to receive the compensation contemplated by these arrangements in accordance with their respective terms and conditions.

Q:

What vote of Newport stockholders is required to approve the Merger-Related Named Executive Officer Compensation Proposal?

A:

Assuming a quorum is present, the affirmative vote of a majority of the shares of Company Common Stock, present in person or represented by proxy at the special meeting and entitled to vote, is required to approve the Merger-Related Named Executive Officer Compensation Proposal. The vote regarding the Merger-Related Named Executive Officer Compensation Proposal is an advisory vote, and therefore, is not binding on Newport or the Company Board or the Company's compensation committee. If you indicate on your proxy that you abstain from voting on the Merger-Related Named Executive Officer Compensation Proposal, it will have with respect to the Merger-Related Named Executive Compensation Proposal, the same effect as voting " AGAINST " the Merger-Related Named Executive Officer Compensation Proposal. If you are a holder of record of Company Common Stock on the Record Date and do not vote, or if your shares of Company Common Stock are held in "street name," which means your shares are held of record by a broker, bank or other nominee, and you fail to give voting instructions to your broker, bank or other nominee, it will have no effect on the outcome of the Merger-Related Named Executive Officer Compensation Proposal (unless you give voting instructions to your broker, bank, or other nominee with respect to at least one other proposal to be voted on at the special meeting, in which case your failure to give such voting instructions with respect to the Merger-Related Named Executive Officer Compensation Proposal will have the same effect as voting " AGAINST " the Merger-Related Named Executive Officer Compensation Proposal).

Q:

How many votes am I entitled to cast for each share of Company Common Stock I own?

A:

For each share of Company Common Stock that you owned on the Record Date, you are entitled to cast one vote on each matter to be voted upon at the special meeting. As of the Record Date, there were 38,879,965 shares of Company Common Stock outstanding and entitled to vote, held by 731 stockholders of record based upon the records of our transfer agent, which do not include

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beneficial owners of Company Common Stock whose shares are held in the names of various brokers, banks and other nominees.

Q:

What constitutes a quorum?

A:

The presence in person or by proxy of a majority of the shares of Company Common Stock issued and outstanding and entitled to vote on the Record Date is required for a quorum at the special meeting. Abstentions are counted as present for purposes of determining the presence of a quorum. A broker non-vote is counted as present for purposes of determining the presence of a quorum if the beneficial owner whose failure to provide voting instructions with respect to a particular proposal that has resulted in such broker non-vote has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting. Otherwise, a broker non-vote is not counted as present for purposes of determining the presence of a quorum.

Q:

What will happen if I abstain from voting or fail to vote on the proposals or fail to instruct my broker, bank or other nominee to vote on the proposals?

A:

If you indicate on your proxy that you abstain from voting on a proposal, it will have the same effect as a vote against the Merger Proposal, the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal.

If you are the holder of record of your shares of Company Common Stock on the Record Date, and you do not attend the meeting and fail to cast your vote, by proxy card or electronically via the Internet or by telephone, it will have the same effect as a vote against the Merger Proposal, and it will have no effect on the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal.

If your shares of Company Common Stock are held in "street name," which means your shares are held of record by a broker, bank or other nominee, and you fail to give voting instructions to your broker, bank or other nominee, it will have the same effect as a vote against the Merger Proposal, but it will have no effect on the outcome of the Adjournment Proposal or the outcome of the Merger-Related Named Executive Officer Compensation Proposal (unless, in the case of each of the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal, you give voting instructions to your broker, bank or other nominee with respect to at least one other proposal to be voted on at the special meeting, in which case your failure to give such voting instructions with respect to the Adjournment Proposal or the Merger-Related Named Executive Officer Compensation Proposal, as applicable, will have the same effect as voting " AGAINST " such proposal).

Q:

When should I submit my proxy?

A:

You should submit your proxy as soon as possible so that your shares will be voted at the special meeting. Proxies must be received by the Company by the day before the meeting in order to be voted at the special meeting.

Q:

Can I change my vote after I have delivered my proxy?

A:

Yes. If you were a Company stockholder of record on the Record Date, you may revoke your proxy and change your vote at any time before your proxy is voted at the special meeting. You can do this in one of four ways:

•

delivering to our corporate secretary a signed written notice of revocation, bearing a date later than the date of the proxy, stating that the proxy is revoked (written revocations may be sent to

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our Corporate Secretary at our corporate offices at 1791 Deere Avenue, Irvine, California 92606);

•

signing and delivering a new paper proxy, relating to the same shares and bearing a later date than the original proxy;



•

submitting another proxy by telephone or over the Internet by 11:59 p.m. Eastern time on the date prior to the date of the special meeting (your latest telephone or Internet proxy submitted by such time will govern); or



•

attending the special meeting and voting in person, although attendance at the special meeting will not, by itself, revoke a proxy.

If you have instructed a broker, bank or other nominee to vote your shares, you must follow the directions received from your broker, bank or other nominee to change those instructions.

Q:

What should I do if I receive more than one set of voting materials?

A:

You may receive more than one set of voting materials, including multiple copies of this proxy statement and multiple proxy cards or voting instruction cards. For example, if you hold your shares of Company Common Stock in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold shares. If you are a holder of record and your shares are registered in more than one name, you will receive more than one proxy card. In order to ensure that all of your shares are voted at the special meeting, please complete, sign, date and return each proxy card and voting instruction card that you receive.

Q:

Am I entitled to dissenters' rights in connection with the Merger?

A:

Because the Company Common Stock was listed on NASDAQ on the Record Date and the merger consideration is cash, you will not be entitled to dissenters' rights under the Nevada Revised Statutes (the " NRS ").

Q:

Is the Merger expected to be taxable to me?

A:

The Merger will be a taxable transaction for U.S. federal income tax purposes. In general, a U.S. holder (as defined in " The Merger—Material U.S. Federal Income Tax Consequences " beginning on page 61 of this proxy statement) whose shares of Company Common Stock are cancelled and converted into the right to receive cash in the Merger will recognize gain or loss for U.S. federal income tax purposes equal to the difference, if any, between the amount of cash received with respect to such shares (determined before the deduction of any required withholding tax) and the holder's adjusted tax basis in such shares. A "non-U.S. holder" (as defined in " The Merger—Material U.S. Federal Income Tax Consequences " beginning on page 61 of this proxy statement) whose shares of Company Common Stock are cancelled and converted into the right to receive cash in the Merger will generally not be required to recognize gain or loss for U.S. federal income tax purposes unless the non-U.S. holder has certain connections to the United States.

You should read " The Merger—Material U.S. Federal Income Tax Consequences " beginning on page 61 of this proxy statement for a more complete discussion of the U.S. federal income tax consequences of the Merger.

Because individual circumstances may differ, you should consult your tax advisor to determine the particular U.S. federal, state, local and/or foreign tax consequences of the Merger to you.

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Q:

Should I send in my share certificates now?

A:

No, please do not send us your share certificates at this time. After the Merger is completed, Wells Fargo Shareowner Services, our paying agent, will send you a letter of transmittal with written instructions for exchanging your share certificates (and/or any uncertificated shares that you may hold in book entry form) for the merger consideration. These instructions will tell you how and where to send in your certificates for your merger consideration. You will receive your cash payment after the paying agent receives your share certificates and any other documents requested in the instructions.

If you are not a registered stockholder—that is, if you hold your shares of Company Common Stock in "street name,"—then payment of the merger consideration in exchange for your shares will be processed in accordance with the applicable procedures of your broker, bank or other nominee.

Q:

What should I do if I have lost my share certificates?

A:

If you have lost your share certificates, please contact our transfer agent, Wells Fargo Shareowner Services, at (800) 468-9716, to obtain replacement certificates.

Q:

What happens if the Merger is not completed?

A:

If our stockholders do not approve the Merger Proposal or if the Merger is not completed for any other reason, our stockholders will not receive any payment for their shares of Company Common Stock in connection with the Merger. Instead, we would remain an independent public company, and shares of Company Common Stock would continue to be listed and traded on NASDAQ. Under specified circumstances, we may be required to pay Parent a termination fee of $32,600,000 as described in " The Merger Agreement—Transaction Expenses and Termination Fees " beginning on page 88 of this proxy statement.

Q:

What happens if I sell my shares of Company Common Stock before the special meeting?

A:

The Record Date is earlier than the date of the special meeting and the date that the Merger is expected to be completed. If you transfer your shares of Company Common Stock after the Record Date, but before the special meeting, you will retain your right to vote at the special meeting, but will transfer the right to receive $23.00 per share in cash, without interest and subject to deduction for any required withholding tax, to be received by our stockholders in the Merger. The merger consideration is payable only to those stockholders who hold their shares immediately prior to the effective time of the Merger.

Q:

Are there any other risks to me from the Merger which I should consider?

A:

Yes. There are risks associated with all business combinations, including the Merger. Please see the section titled " Cautionary Statement Concerning Forward-Looking Statements " on page 22.

Q:

Who can help answer my questions?

A:

If you have any questions about the Merger or how to submit your proxy, or if you would like additional copies, without charge, of this proxy statement or the enclosed proxy card, you should contact our proxy solicitor, MacKenzie Partners Inc., at:

Call Collect: (212) 929-5500
Toll Free: (800) 322-2885
Email to: proxy@mackenziepartners.com
Address: 105 Madison Avenue, New York, New York 10016

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SUMMARY

         This summary, together with the preceding section of this proxy statement entitled "Questions and Answers About the Merger and the Special Meeting," highlights selected information from this proxy statement and may not contain all of the information that is important to you as a stockholder of Newport or that you should consider before voting on the Merger Proposal. To better understand the Merger, you should read carefully this entire proxy statement and all of its annexes, including the Merger Agreement, which is attached as Annex A, before voting on the Merger Proposal. In addition, we incorporate by reference important business and financial information about Newport in this document. Each item in this summary includes a page reference directing you to a more complete description of that item. You may obtain without charge copies of documents incorporated by reference into this proxy statement by following the instructions under "Where You Can Find More Information" beginning on page 99 of this proxy statement.

The Companies (page 28)

Newport Corporation
1791 Deere Avenue
Irvine, CA 92606
(949) 863-3144
www.newport.com

        Newport is a global supplier of advanced technology products and systems to a wide range of industries, including scientific research, microelectronics, defense and security, life and health sciences, and industrial markets. Newport provides a broad portfolio of products to customers in these end markets, allowing us to offer them an end-to-end resource for photonics solutions. Newport provides a wide range of photonics technology and products designed to enhance the capabilities and productivity of our customers' precision applications, including: lasers and laser technology, including solid-state lasers, ultrafast lasers and laser systems, tunable lasers and fiber lasers; optical components and subassemblies, including precision laser optics and opto-mechanical subassemblies, optics and lens assemblies for thermal imaging, thin-film optical filters, and ruled and holographic diffraction gratings; photonics instruments, systems and components, including optical power and energy meters, light sources, optical detectors and modulators, laser beam profilers, monochromators, spectroscopy instrumentation, laser diode controllers and drivers, and laser diode burn-in and life test systems; high-precision positioning products and systems; vibration isolation products and systems; and three-dimensional non-contact measurement sensors and equipment.

         For additional information about Newport and our business, see the section entitled "Where You Can Find More Information" beginning on page 99 of this proxy statement.

MKS Instruments, Inc.
2 Tech Drive, Suite 201
Andover, MA 01810
(978) 645-5500
www.mksinst.com

        MKS Instruments, Inc. was founded in 1961 as a Massachusetts corporation. The company is a global provider of instruments, subsystems and process control solutions that measure, control, power, monitor and analyze critical parameters of advanced manufacturing processes to improve process

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performance and productivity. The company also provides services relating to the maintenance and repair of its products, software maintenance, installation services and training.

PSI Equipment, Inc.
2 Tech Drive, Suite 201
Andover, MA 01810
(978) 645-5500

        PSI Equipment, Inc. a Nevada corporation and a wholly owned subsidiary of Parent, was organized solely for the purpose of entering into the Merger Agreement with Newport and completing the Merger and has not conducted any business operations other than those incident to its formation and the transactions contemplated by the Merger Agreement. If the Merger is completed, Merger Sub will cease to exist following its merger with and into Newport.

The Merger (page 28)

        Pursuant to the terms of the Merger Agreement, Newport will be acquired by Parent. We encourage you to carefully read in its entirety the Merger Agreement, which is the principal document governing the Merger. The Merger Agreement is attached to this proxy statement as Annex A.

        The Merger Agreement provides that Merger Sub will merge with and into Newport, with Newport continuing as the surviving corporation and a wholly owned subsidiary of Parent. Upon the completion of the Merger, each share of Company Common Stock outstanding immediately prior to the effective time of the Merger (other than the Excluded Shares), will be cancelled and converted into the right to receive $23.00 in cash, without interest and subject to deduction for any required withholding tax.

Treatment of Newport Equity Awards (page 68)

        Restricted Stock Units.     At the effective time of the Merger, each Company RSU granted under any Company Equity Plan that is outstanding immediately prior to the effective time of the Merger and as to which shares of Company Common Stock will not have been fully distributed in connection with the closing of the Merger will be assumed by Parent, and will continue to have and be subject to the same terms and conditions (including the same vesting conditions) as were in effect for such Company RSU immediately prior to the effective time of the Merger, except that such Company RSU will become an award for a number of shares of Parent Common Stock equal to the number of shares of Company Common Stock subject to such Company RSU multiplied by the Equity Award Exchange Ratio (with the result rounded down to the nearest whole share).

        Stock Appreciation Rights.     At the effective time of the Merger, each Company SAR, whether vested or unvested, that is outstanding immediately prior to the effective time of the Merger will be assumed by Parent, and will continue to have and be subject to the same terms and conditions (including vesting schedule) as were in effect for such Company SAR immediately prior to the effective time of the Merger, except that such Company SAR will become an award for a number of shares of Parent Common Stock equal to the number of shares of Company Common Stock subject to such Company SAR, multiplied by the Equity Award Exchange Ratio (rounded down to the nearest whole share), with a per share base value equal to the per share base value for such Company SAR immediately prior to the effective time of the Merger, divided by the Equity Award Exchange Ratio (rounded up to the nearest whole cent).

        Notwithstanding the above, the Merger Agreement provides that the treatment described above may be changed by agreement of the Company and Parent with respect to Company RSUs and Company SARs held by non-U.S. employees and/or non-employee directors of the Company. As permitted by the Merger Agreement, the Company intends to cause all Company RSUs held by

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non-employee directors of the Company to accelerate and vest in full and be settled immediately prior to the effective time of the Merger.

Treatment of Newport's Employee Stock Purchase Plan (page 69)

        New offerings under the Company's employee stock purchase plan (the " Company ESPP ") have been frozen such that no offering or purchase period will begin on or after the date of the Merger Agreement. The Company ESPP will terminate no later than the business day immediately preceding the closing date for the Merger in accordance with its terms in such manner as results in no participant in the Company ESPP having any right at or after the effective time of the Merger to (A) purchase shares of Company Common Stock or any other security of the Company, Parent, the Surviving Corporation or any other person under the Company ESPP or (B) receive any cash payment or other consideration for his or her terminated rights under the Company ESPP (other than a refund of amounts withheld by the Company on behalf of such participant that have not been used to purchase shares of Company Common Stock prior to the termination of the Company ESPP, without interest, pursuant to the terms of the Company ESPP upon the termination of the Company ESPP).

The Newport Special Meeting (page 23)

        The special meeting of stockholders will be held on April 27, 2016 at 9:00 a.m., local time, at 1791 Deere Avenue, Irvine, CA 92606. At the special meeting, you will be asked to consider and vote on the Merger Proposal, the Adjournment Proposal, and the Merger-Related Named Executive Officer Compensation Proposal.

Stockholders Entitled to Vote; Record Date (page 24)

        Only holders of record of shares of Company Common Stock on the Record Date may vote at the special meeting. For each share of Company Common Stock that you owned on the Record Date, you are entitled to cast one vote on each matter voted upon at the special meeting. On the Record Date, there were 38,879,965 shares of Company Common Stock outstanding and entitled to vote at the special meeting.

Quorum and Vote Required (page 24)

        A quorum of stockholders is necessary to hold the special meeting. The required quorum for the transaction of business at the special meeting shall exist when the holders of a majority of the shares of Company Common Stock entitled to vote at the special meeting are either present in person or represented by proxy. If a quorum is not present at the special meeting, we expect that the special meeting will be adjourned to solicit additional proxies. Abstentions count as present for establishing a quorum. A broker non-vote counts for purposes of establishing a quorum if the beneficial owner whose failure to provide voting instructions with respect to a particular proposal that has resulted in such broker non-vote has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting. Otherwise, a broker non-vote does not count for purposes of establishing a quorum.

        Approval of the Merger Proposal requires the affirmative vote of the holders of a majority of the shares of Company Common Stock entitled to vote. Failure to vote, by proxy or in person, will have the same effect as a vote "AGAINST" the Merger Proposal . The Adjournment Proposal will be approved if a majority of the shares of Company Common Stock, present in person or represented by proxy and entitled to vote at the special meeting, vote in favor of the proposal. The Merger-Related Named Executive Officer Compensation Proposal will be approved if a majority of the shares of Company Common Stock, present in person or represented by proxy and entitled to vote at the special meeting, vote in favor of the proposal.

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Shares Owned by Our Directors and Executive Officers (page 25)

        As of the Record Date, our directors and executive officers were entitled to vote approximately 728,556 shares of Company Common Stock, or approximately 1.87% of total Company Common Stock outstanding on that date. These numbers do not give effect to outstanding Company RSUs, which are not entitled to vote at the special meeting. Our directors and executive officers have each entered into a stockholder agreement (collectively, the " Stockholder Agreements ") with Parent. Each Stockholder Agreement (i) requires the applicable stockholder to vote such stockholder's shares of Company Common Stock in favor of (and to grant a proxy to Parent to vote in favor of) adoption and approval of the Merger Agreement and to vote against the approval or adoption of any alternative acquisition proposal and (ii) prohibits the applicable stockholder from transferring such stockholder's shares of Company Common Stock, each subject to the exceptions described in the Stockholder Agreement. A copy of the form of Stockholder Agreement is attached to this proxy statement as Annex B. We currently expect that each of our directors and executive officers will vote their shares in favor of the proposals to be presented at the special meeting, in accordance with the terms of the Stockholder Agreements.

Market Price (page 95)

        Company Common Stock is listed on NASDAQ under the symbol "NEWP." On February 22, 2016, the last trading date prior to public announcement of the proposed Merger, Company Common Stock closed at $15.04. On March 24, 2016, the most recent practicable trading date prior to the date of this proxy statement, the closing price per share of Company Common Stock on NASDAQ was $22.96.

        We did not declare any dividends on Company Common Stock during 2014 or 2015. In addition, pursuant to the Merger Agreement, we are prohibited from declaring any dividends following execution of the Merger Agreement with respect to any of our capital stock or other securities. Following the Merger, there will be no further market for Company Common Stock.

Recommendation of the Company Board; Our Reasons for the Merger (page 40)

        The Company Board unanimously recommends that you vote " FOR " the Merger Proposal, " FOR " the Adjournment Proposal and " FOR " the Merger-Related Named Executive Officer Compensation Proposal.

        In considering its decision to approve the Merger Agreement and to authorize and approve the Merger, and, subject to the terms and conditions of the Merger Agreement, to recommend the approval of the Merger Proposal, the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal by our stockholders, the Company Board consulted with our management, as well as our legal and financial advisors, and considered the terms of the proposed Merger Agreement and the transactions set forth in the Merger Agreement, as well as other alternative transactions, including contacts and extensive discussions with other potential acquirers.

        The Company Board's reasons for approving the Merger and Merger Agreement, certain factors the Company Board considered in its deliberations in approving the Merger and Merger Agreement, and the recommendations of the Company Board to the Company stockholders regarding the Merger Proposal, the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal are further discussed in the section entitled " The Merger—Recommendation of the Company Board; Our Reasons for the Merger " beginning on page 40 of this proxy statement.

Interests of Our Directors and Executive Officers in the Merger (page 56)

        In considering the recommendation of the Company Board that the stockholders vote to approve the Merger Proposal, the stockholders should be aware that some of our directors and executive

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officers have interests in the Merger that are different from, or in addition to, the interests of the stockholders generally. Interests of the directors and executive officers may be different from or in addition to the interests of the stockholders for the following reasons, among others:

•

The Merger Agreement provides that, as of the effective time of the Merger, each Company RSU granted under any Company Equity Plan that is outstanding immediately prior to the effective time of the Merger and as to which shares of Company Common Stock have not been fully distributed in connection with the closing of the Merger will be assumed by Parent and continue to be subject to the same terms and conditions (including vesting schedules) as in effect for such Company RSU immediately prior to the effective time of the Merger, except that following the Merger each such Company RSU will become an award for a number of shares of Parent Common Stock equal to the number of shares of Company Common Stock subject to such Company RSU multiplied by the Equity Award Exchange Ratio (with the result rounded down to the nearest whole share).



•

The Merger Agreement provides that, as of the effective time of the Merger, each Company SAR, whether vested or unvested, that is outstanding immediately prior to the effective time of the Merger will be assumed by Parent and continue to be subject to the same terms and conditions (including vesting schedule) as in effect for such Company SAR immediately prior to the effective time of the Merger, except that following the Merger each such Company SAR will become an award for a number of shares of Parent Common Stock equal to the number of shares of Company Common Stock subject to such Company SAR, multiplied by the Equity Award Exchange Ratio (rounded down to the nearest whole share), with a per share base value equal to the per share base value for such Company SAR immediately prior to the effective time of the Merger, divided by the Equity Award Exchange Ratio (rounded up to the nearest whole cent).



•

Notwithstanding the above, the Merger Agreement provides that the treatment described above may be changed by agreement of the Company and Parent with respect to Company RSUs and Company SARs held by non-U.S. employees and/or non-employee directors of the Company. As permitted by the Merger Agreement, the Company intends to cause all Company RSUs held by non-employee directors of the Company to accelerate and vest in full and be settled immediately prior to the effective time of the Merger.



•

Each of our named executive officers is party to an individual Severance Compensation Agreement (as defined in " The Merger—Interests of Our Directors and Executive Officers in the Merger " beginning on page 56 of this proxy statement) that provides for severance benefits in the event of certain Qualifying Terminations (as defined in " The Merger—Interests of Our Directors and Executive Officers in the Merger " beginning on page 56 of this proxy statement) of employment within the period of time commencing on the effective time of the Merger and ending two years after the effective time of the Merger.



•

Our directors and executive officers are entitled to continued indemnification, expense advancement and insurance coverage under the Merger Agreement.

        These interests are discussed in more detail in the section entitled " The Merger—Interests of Our Directors and Executive Officers in the Merger " beginning on page 56 of this proxy statement. The members of the Company Board were aware of the different or additional interests described in such section and considered these interests, among other matters, in evaluating and negotiating the Merger Agreement and the Merger, and in recommending to the stockholders that the Merger Proposal be approved.

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Opinion of J.P. Morgan Securities LLC (page 44 and Annex C)

        Pursuant to an engagement letter dated January 28, 2016, we retained J.P. Morgan Securities LLC (" J.P. Morgan ") as our financial advisor in connection with a potential transaction. We selected J.P. Morgan to act as our financial advisor based on J.P. Morgan's qualifications, expertise, reputation and knowledge of our business and affairs and the industry in which we operate.

        At the meeting of the Company Board on February 22, 2016, J.P. Morgan rendered its oral opinion to the Company Board that, as of such date and based upon and subject to the factors and assumptions set forth in its opinion, the consideration to be paid to holders of Company Common Stock in the proposed Merger was fair, from a financial point of view, to such holders. J.P. Morgan confirmed its February 22, 2016 oral opinion by delivering its written opinion to the Company Board, dated February 22, 2016, that, as of such date, the consideration to be paid to the holders of Company Common Stock in the proposed Merger was fair, from a financial point of view, to such holders.

        The full text of the written opinion of J.P. Morgan, dated February 22, 2016, which sets forth the assumptions made, matters considered and limits on the review undertaken, is attached as Annex C to this proxy statement and is incorporated herein by reference. Holders of Company Common Stock are urged to read the opinion attached as Annex C to this proxy statement and the summary of the opinion set forth in the section of this proxy statement entitled " The Merger—Opinion of J.P. Morgan Securities LLC " in their entirety. J.P. Morgan's written opinion was addressed to the Company Board (in its capacity as such) in connection with and for the purposes of its evaluation of the proposed Merger, was directed only to the consideration to be paid in the proposed Merger, did not address any other aspect of the proposed Merger and does not constitute a recommendation to any holder of Company Common Stock as to how such holder should vote at the special meeting. The summary of the opinion of J.P. Morgan set forth in the section of this proxy statement captioned " The Merger—Opinion of J.P. Morgan Securities LLC " is qualified in its entirety by reference to the full text of such opinion.

        For a more complete description, see the section of this proxy statement captioned " The Merger—Opinion of J.P. Morgan Securities LLC. "

Delisting and Deregistration of Company Common Stock (page 61)

        If the Merger is completed, Company Common Stock will no longer be listed on NASDAQ, we will be deregistered under the Securities Exchange Act of 1934, as amended (the " Exchange Act "), and we will no longer file periodic reports with the SEC.

The Merger Agreement (page 67)

Conditions to Completion of the Merger

        The obligation of each party to effect the Merger is subject to the satisfaction at or prior to the effective time of the Merger of the following conditions:

•

The Merger Agreement and the Merger will have been adopted and approved by the Company's stockholders at a meeting of the Company's stockholders;



•

No temporary restraining order, preliminary or permanent injunction or other judgment, order or decree issued by any court of competent jurisdiction or other legal restraint or prohibition shall be in effect, and no law shall have been enacted, entered, promulgated, enforced or deemed applicable by any governmental entity that, in any case, prohibits or makes illegal the consummation of the Merger; and



•

Any applicable waiting periods will have expired or been terminated, and any approvals required will have been obtained, in each case relating to the transactions contemplated by the Merger

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Agreement under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the " HSR Act ") or under the antitrust law of Germany or Israel, as specified in the disclosure letter delivered by the Company to Parent in connection with the Merger Agreement.

        The obligation of the Company to effect the Merger is also subject to the satisfaction or waiver at or prior to the effective time of the Merger of the following conditions:

•

Subject to specified qualifications and exceptions, the truth and correctness of the representations and warranties of Parent and Merger Sub contained in the Merger Agreement as of the date of the Merger Agreement and the effective time of the Merger;



•

Parent and Merger Sub will have performed in all material respects all obligations required to be performed by them under the Merger Agreement at or prior to the effective time of the Merger; and



•

The receipt by the Company of a certificate executed by an executive officer of Parent certifying the satisfaction of the foregoing conditions.

        The obligation of the Parent and Merger Sub to effect the Merger is also subject to the satisfaction or waiver at or prior to the effective time of the Merger of the following conditions:

•

Subject to specified qualifications and exceptions, the truth and correctness of the Company's representations and warranties contained in the Merger Agreement as of the date of the Merger Agreement and the effective time of the Merger;



•

The Company will have performed in all material respects all obligations required to be performed by it under the Merger Agreement at or prior to the effective time of the Merger;



•

Since the date of the Merger Agreement, there shall not have occurred any event, change, occurrence or effect that, individually or in the aggregate, has had or would reasonably be expected to have a material adverse effect, as discussed in the section entitled " The Merger Agreement—Representations and Warranties " beginning on page 70 of this proxy statement;



•

The absence of certain pending suits, actions or proceedings by any governmental entity; and



•

The receipt by Parent of a certificate executed by each of the Company's chief executive officer and chief financial officer certifying the satisfaction of the foregoing conditions.

No-Shop; Acquisition Proposals; Change in Recommendation

        Following the date of the Merger Agreement, the Company and its subsidiaries, and their respective officers, directors, employees, agents, advisors and representatives, may not, directly or indirectly: (i) initiate, solicit, knowingly facilitate or knowingly encourage any inquiries, proposals or offers with respect to, or the making or completion of, an Acquisition Proposal (as defined in " The Merger Agreement—No-Shop; Acquisition Proposals; Change in Recommendation " beginning on page 78 of this proxy statement), or any inquiry, proposal or offer that could reasonably be expected to lead to an Acquisition Proposal; (ii) engage or participate in any negotiations or discussions concerning, or provide any information or data relating to the Company and its subsidiaries in connection with, an Acquisition Proposal, or any inquiry, proposal or offer that could reasonably be expected to lead to an Acquisition Proposal; (iii) approve, endorse or recommend any Acquisition Proposal; or (iv) execute or enter into any letter of intent, agreement in principle, merger agreement, acquisition agreement or other similar contract relating to an Acquisition Proposal or any inquiry, proposal or offer that could reasonably be expected to lead to an Acquisition Proposal.

        Notwithstanding the foregoing, at any time prior to the adoption and approval of the Merger Agreement and the Merger by the Company's stockholders, the Company may, in response to an unsolicited, bona fide written Acquisition Proposal that the Company Board determines in good faith,

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after consultation with its outside counsel and its independent financial advisor, constitutes or would reasonably be expected to lead to a Superior Proposal (as defined in " The Merger Agreement—No-Shop; Acquisition Proposals; Change in Recommendation " beginning on page 78 of this proxy statement) (i) furnish information with respect to the Company and its subsidiaries to the person making such Acquisition Proposal pursuant to a confidentiality agreement no less favorable to the Company than the confidentiality agreement between the Company and Parent and (ii) participate in discussions or negotiations with such person and its representatives regarding the Acquisition Proposal.

        The Company must advise Parent within 24 hours of receipt of any Acquisition Proposal, request for information relating to the Company or its subsidiaries, or inquiry or request for discussion or negotiation regarding, or that could reasonably be expected to lead to, an Acquisition Proposal. Such notice must include the identity of the person making the Acquisition Proposal, inquiry or request, and the material terms thereof. The Company must also keep Parent reasonably informed of the status and details of any such Acquisition Proposal, request or inquiry, and provide Parent copies of any information provided to or received from the person making such Acquisition Proposal, request or inquiry.

        Generally, the Company Board is prohibited from (i) withdrawing or modifying in a manner adverse to Parent and Merger Sub its recommendation in favor of the Merger Agreement and the Merger to the Company stockholders or (ii) approving or recommending an Acquisition Proposal (each, an " Adverse Recommendation Change "). However, the Company Board can make an Adverse Recommendation Change if:

•

the Company Board determines that a Superior Proposal is outstanding;



•

the Company Board reasonably determines in good faith, after consultation with its outside counsel and its independent financial advisor, that its fiduciary obligations require it to make an Adverse Recommendation Change, but at least five business days (or three business days in the case of a change to a Superior Proposal of which Parent has previously been notified) after delivering notice of the contemplated Adverse Recommendation Change to Parent;



•

during such five business day (or three business day) period, the Company provides Parent with a reasonable opportunity to adjust the terms and conditions of the Merger Agreement and negotiates in good faith with Parent to enable the Company Board to proceed with its recommendation in favor of the Merger and the Merger Agreement;



•

the Company complies with the notice requirements described above; and



•

during such five business day (or three business day) period, Parent does not make a proposal that the Company Board determines in good faith, after consultation with its outside counsel and its independent financial advisor, to be at least as favorable from a financial point of view to the Company stockholders as the Superior Proposal.

        The Company Board can also make an Adverse Recommendation Change in response to an Intervening Event (as defined in " The Merger Agreement—No-Shop; Acquisition Proposals; Change in Recommendation " beginning on page 78 of this proxy statement) if:

•

the Company Board has determined in good faith, after consultation with its outside counsel and its independent financial advisor, that in light of such Intervening Event, its fiduciary obligations require it to make an Adverse Recommendation Change;



•

the Company Board has provided notice to Parent of the contemplated Adverse Recommendation Change, and specified the reasons therefor in reasonable detail, at least five business days prior to making such Adverse Recommendation Change; and

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•

during such five business day period, if requested by Parent, the Company has engaged in good faith negotiations with Parent to amend the Merger Agreement to obviate the need to make an Adverse Recommendation Change.

Termination of the Merger Agreement

        The Merger Agreement may be terminated and the Merger may be abandoned at any time prior to the effective time of the Merger by mutual written consent of Parent and the Company. In addition, the Merger Agreement may be terminated prior to the effective time of the Merger by either Parent or the Company if:

•

the Merger has not been consummated on or before 5:00 p.m., Eastern time, on August 22, 2016;



•

any court of competent jurisdiction or other governmental entity has issued a judgment, order, injunction, rule or decree, or taken any other action permanently restraining, enjoining or otherwise prohibiting any of the transactions contemplated by the Merger Agreement and such judgment, order, injunction, rule, decree or other action has become final and non-appealable; or



•

if the approval of the Merger Agreement and the Merger by the Company stockholders is not obtained at the special meeting or at any adjournment or postponement thereof at which a vote on the adoption and approval of the Merger Agreement is taken.

        The Merger Agreement can be terminated prior to the effective time of the Merger by the Company:

•

if Parent or Merger Sub has breached or failed to perform any of its representations, warranties, covenants or agreements in the Merger Agreement, and such breach or failure to perform (i) would result in the failure of a closing condition described in " —Conditions to Completion of the Merger " and (ii) cannot be, or has not been, cured within 20 days after the Company has given Parent written notice of such breach or failure and stating the Company's intention to terminate the Merger Agreement; or



•

prior to the adoption and approval of the Merger Agreement and the Merger by the Company stockholders, to enter into a transaction that is a Superior Proposal, if (i) the Company Board has received a Superior Proposal; (ii) the Company has complied in all material respects with its obligations described under " —No Shop; Acquisition Proposals; Change in Recommendation "; (iii) the Company Board approves, and concurrently with the termination of the Merger Agreement the Company enters into, a definitive agreement with respect to such Superior Proposal; and (iv) prior to or concurrently with such termination, the Company pays to Parent the termination fee described in " —Transaction Expenses and Termination Fees " below.

        The Merger Agreement can be terminated prior to the effective time of the Merger by Parent:

•

if the Company has breached or failed to perform any of its representations, warranties, covenants or agreements in the Merger Agreement, and such breach or failure to perform (i) would result in the failure of a closing condition described in " —Conditions to Completion of the Merger " and (ii) cannot be, or has not been, cured within 20 days after Parent has given the Company written notice of such breach or failure and stating Parent's intention to terminate the Merger Agreement; or

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•

if: (i) an Adverse Recommendation Change has occurred; (ii) the Company Board fails to recommend the approval of the Merger Agreement and the Merger in this proxy statement; (iii) an Acquisition Proposal is publicly announced, distributed or disseminated to the Company stockholders and, following the request of Parent, the Company Board fails to reaffirm its recommendation in favor of the Merger Agreement and the Merger within 10 business days of such request; (iv) the Company Board has approved, endorsed or recommended to the Company stockholders an Acquisition Proposal; (v) a tender offer or exchange offer for Company Common Stock has commenced, and the Company Board recommends that the Company stockholders tender their shares of Company Common Stock in such tender or exchange offer, or within 10 business days after the commencement of such tender or exchange offer, the Company Board fails to recommend against acceptance of such offer; (vi) the Company Board resolves to do any of the foregoing; or (vii) the Company intentionally breaches in any material respect its obligations described in " The Merger Agreement—No Shop; Acquisition Proposals; Change in Recommendation " or the second paragraph of " The Merger Agreement—Stockholder Meetings; Preparation of Proxy Statement. "

Transaction Expenses and Termination Fees

        Subject to certain limited exceptions, all fees and expenses incurred in connection with the Merger Agreement and the Merger will be paid by the party incurring such fees or expenses, whether or not the Merger is consummated. However, the Company must pay Parent a termination fee of $32,600,000 in the event that:

•

the Merger Agreement is terminated because:



•

the Merger has not been consummated on or before 5:00 p.m., Eastern time, on August 22, 2016;



•

the Company has breached or failed to perform any of its representations, warranties, covenants or agreements; or



•

the adoption and approval of the Merger Agreement and the Merger by the Company stockholders is not obtained at the special meeting or at any adjournment or postponement thereof at which a vote on the adoption and approval of the Merger Agreement is taken;



•

and, in addition to the termination of the Merger Agreement for any of the foregoing reasons,



•

at any time on or after the date of the Merger Agreement and prior to such termination or vote, an Acquisition Proposal has been communicated to the senior management of the Company or the Company Board or publicly announced or otherwise made known to the Company stockholders, and



•

within 12 months following such termination, the Company enters into a definitive agreement with respect to an Acquisition Proposal or an Acquisition Proposal is consummated (for purposes of this provision, the references to "15%" in the definition of Acquisition Proposal are deemed to be references to "50%");



•

the Merger Agreement is terminated by the Company to enter into a transaction that is a Superior Proposal;



•

the Merger Agreement is terminated by Parent for any reason set forth in the last bullet in the section " —Termination of the Merger Agreement " above; or

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•

the Merger Agreement is terminated by Parent or the Company because the Merger has not been consummated on or before 5:00 p.m., Eastern time, on August 22, 2016 following an Adverse Recommendation Change in response to an Intervening Event.

Financing of the Merger (page 65)

        Consummation of the Merger is not subject to Parent's ability to obtain financing. However, Parent expects to obtain financing for a portion of the consideration for the Merger. In connection with the Merger Agreement, Parent entered into a debt commitment letter (the " Commitment Letter ") dated as of February 22, 2016, with Barclays Bank PLC (" Barclays "), Deutsche Bank Securities Inc. (" DBSI ") and Deutsche Bank AG New York Branch (together with DBSI and Barclays, the " Commitment Parties "), pursuant to which, among other things, the Commitment Parties have committed to provide Parent with debt financing in the aggregate principal amount of up to $800,000,000 to finance, in part, the acquisition of the Company. In addition, the Commitment Parties have committed under the Commitment Letter to provide Parent with a $50,000,000 asset-based revolving credit facility for working capital purposes, as needed. The Debt Financing (for purposes of this section, as defined in "The Merger Agreement—Financing Matters" ) would be secured by a security interest in substantially all of Parent's, the Company's and their respective domestic subsidiaries' tangible and intangible assets, including certain real property.

        While consummation of the Merger is not subject to Parent's ability to obtain financing, the Commitment Parties' obligations under the Commitment Letter are subject to certain conditions, including consummation of the Merger in accordance with the Merger Agreement; the negotiation and execution of definitive documentation consistent with the Commitment Letter; delivery of certain pro forma and other financial information; subject to certain limitations, the absence of a material adverse effect on the Company; the accuracy of specified representations and warranties of the Company in the Merger Agreement and specified representations and warranties of Parent to be set forth in the definitive loan documents; the repayment of certain outstanding debt of the Company; and other customary closing conditions.

        The definitive documentation governing the Debt Financing has not been finalized and, accordingly, the actual terms of the Debt Financing may differ from those described in this proxy statement. Although the Debt Financing is not subject to due diligence or a "market out," such financing may not be considered assured. Although consummation of the Merger is not subject to Parent's ability to obtain financing, the obligation of the Commitment Parties to provide the Debt Financing under the Commitment Letter is subject to a number of conditions. There is a risk that these conditions will not be satisfied and the Debt Financing may not be available when required.

Material U.S. Federal Income Tax Consequences (page 61)

        The Merger will be a taxable transaction for U.S. federal income tax purposes. In general, a U.S. holder (as defined in " The Merger—Material U.S. Federal Income Tax Consequences " beginning on page 61 of this proxy statement) whose shares of Company Common Stock are cancelled and converted into cash in the Merger will recognize gain or loss for U.S. federal income tax purposes equal to the difference, if any, between the amount of cash received with respect to such shares (determined before the deduction of any applicable withholding taxes) and the holder's adjusted tax basis in such shares. A "non-U.S. holder" (as defined in " The Merger—Material U.S. Federal Income Tax Consequences " beginning on page 61 of this proxy statement) whose shares of Company Common Stock are cancelled and converted into cash in the Merger will generally not be required to recognize gain or loss for U.S. federal income tax purposes unless the non-U.S. holder has certain connections to the United States.

        See the section entitled " The Merger—Material U.S. Federal Income Tax Consequences " beginning on page 61 of this proxy statement for a more complete discussion of the U.S. federal income tax

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consequences of the Merger. The tax consequences of the Merger to you will depend on your particular tax situation. You should consult your tax advisor for a complete analysis of the U.S. federal, state, local and/or foreign tax consequences of the Merger to you.

Regulatory Matters (page 64)

        Under the HSR Act, and the rules and regulations promulgated thereunder by the U.S. Federal Trade Commission (the " FTC "), the Merger cannot be consummated until, among other things, notifications have been given and certain information has been furnished to the FTC and the Antitrust Division of the U.S. Department of Justice and all applicable waiting periods have expired or been terminated. Pre-Merger filings and governmental approvals are also required from the antitrust authorities in Germany and Israel. The parties submitted filings required under the HSR Act on February 29, 2016, submitted the requisite filings with the antitrust authorities in Germany on March 8, 2016 and submitted the requisite filings with the antitrust authorities in Israel on March 22, 2016. Early termination of the waiting period under the HSR Act was granted on March 14, 2016.

Dissenters' Rights (page 94)

        Under NRS Section 92A.390, when the merger consideration is cash, there is no right of dissent with respect to a plan of merger, conversion or exchange in favor of stockholders of any class or series that is a "covered security" under Section 18(b)(l)(A) or (B) of the Securities Act of 1933, as amended. The shares of Company Common Stock are covered securities because they are traded on NASDAQ. Because the shares of Company Common Stock were covered securities on the Record Date and the merger consideration is cash, holders of shares of Company Common Stock will not have dissenters' rights in connection with the Merger.

Legal Proceedings Relating to the Merger (page 66)

        On March 9, 2016, a putative class action complaint captioned Dixon Chung v. Newport Corp., et al. , Case No. A-16-733154-C, was filed in the District Court, Clark County, Nevada on behalf of a putative class of the Company's stockholders. The complaint names as defendants the Company, Parent, Merger Sub and certain current and former members of the Company Board. The complaint alleges that the named directors breached their fiduciary duties to the Company's stockholders by agreeing to sell the Company through an inadequate and unfair process, which led to inadequate and unfair consideration, and by agreeing to unfair deal-protection devices. The complaint also alleges that the Company, Parent and Merger Sub aided and abetted the named directors' alleged breaches of their fiduciary duties. The complaint seeks injunctive relief, including to enjoin or rescind the Merger, monetary damages, and an award of attorneys' and other fees and costs, among other relief.

        See the section entitled " The Merger—Legal Proceedings Relating to the Merger " beginning on page 66 of this proxy statement.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        This proxy statement, the documents to which we refer you in this proxy statement and information included in oral statements or other written statements made or to be made by us or on our behalf may include predictions, estimates and other information that are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, Section 21E of the Securities Exchange Act of 1934, as amended (the " Exchange Act ") and Section 27A of the Securities Act of 1933, as amended (the "Securities Act"). These forward-looking statements do not directly or exclusively relate to historical facts, including, without limitation, statements relating to the completion of the Merger. Without limiting the generality of the foregoing, words such as "anticipate," "believe," "can," "continue," "could," "estimate," "expect," "intend," "may," "plan," "potential," "predict," "should," "will," "would," or the negative or other variations thereof or comparable terminology are intended to identify forward-looking statements. Stockholders are cautioned that any forward-looking statements are not guarantees of future performance. These statements are based on current expectations and assumptions based on available information and involve a number of risks and uncertainties, all of which are difficult or impossible to predict accurately and many of which are beyond our control. As such, our actual results may differ significantly from those expressed in any forward-looking statements.

        These risks and uncertainties include, but are not limited to, factors and matters described or incorporated by reference in this proxy statement and the following factors: (1) the ability of the parties to consummate the Merger, (2) risks that the conditions to the closing of the Merger are not satisfied, including the risk that required approvals for the Merger from governmental authorities or the stockholders of the Company are not obtained; (3) litigation relating to the Merger; (4) the ability of Parent to successfully integrate the Company's operations and employees; (5) unexpected costs, charges or expenses resulting from the Merger; (6) risks that the proposed Merger disrupts the current plans and operations of the Company and Parent; (7) the ability to realize anticipated synergies and cost savings from the Merger; (8) competition from larger and more established companies in the Company's markets; (9) Parent's ability to successfully grow the Company's business; (10) potential adverse reactions or changes to business relationships resulting from the announcement or completion of the Merger; (11) the availability and terms of the financing to be incurred in connection with the Merger; (12) the retention of key employees; and (13) legislative, regulatory and economic developments, including changing business conditions in the industries in which the Company and Parent operate and the economy in general as well as financial performance and expectations of the Company's and Parent's existing and prospective customers. Additional factors that may affect the future results of the Company are set forth in filings the Company makes with the Securities and Exchange Commission (the " SEC ") from time to time, including its Annual Report on Form 10-K for the year ended January 2, 2016, which is available on the SEC's website at www.sec.gov.

        In light of the significant risks and uncertainties inherent in the forward-looking information included herein, the inclusion of such information should not be regarded as a representation by us or any other person that such results will be achieved, and readers are cautioned not to place undue reliance on such forward-looking information, which speak only as of the date hereof. Except as required by law, we undertake no obligation to revise the forward-looking statements contained herein to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

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THE SPECIAL MEETING

General

        Your proxy is solicited on behalf of the Board of Directors of the Company (the " Company Board ") for use at our special meeting of stockholders to be held on April 27, 2016, at 9:00 a.m., local time, at 1791 Deere Avenue, Irvine, CA 92606, or at any continuation, postponement or adjournment thereof, for the purposes discussed in this proxy statement and in the accompanying Notice of Special Meeting and any other business properly brought before the special meeting. Proxies are solicited to give all stockholders of record an opportunity to vote on matters properly presented at the special meeting. On or about March 29, 2016, we commenced mailing this proxy statement and the enclosed form of proxy to our stockholders entitled to vote at our special meeting.

Date, Time and Place of the Special Meeting

        We will hold the special meeting on April 27, 2016, at 9:00 a.m., local time, at 1791 Deere Avenue, Irvine, CA 92606. Directions to attend the special meeting can be found on our website at www.newport.com/investors.

Purpose of the Special Meeting

        At the special meeting, we are asking holders of record of our common stock, par value $0.1167 per share (" Company Common Stock "), on March 21, 2016, to consider and vote on the following:

        1.     To adopt and approve the Agreement and Plan of Merger, dated as of February 22, 2016 (the " Merger Agreement "), by and among the Company, MKS Instruments, Inc. (" Parent "), and PSI Equipment, Inc. (" Merger Sub "), a copy of which is attached as Annex A to this proxy statement, and the transactions contemplated thereby, including the merger of Merger Sub with and into the Company (the " Merger "), with the Company surviving the Merger as a wholly owned subsidiary of Parent (the " Merger Proposal ");

        2.     To approve the postponement or adjournment of the special meeting to solicit additional proxies if there are not sufficient votes to approve the Merger Proposal, if deemed necessary or appropriate by the Company Board (the " Adjournment Proposal "); and

        3.     To approve on a non-binding, advisory basis, certain compensation that will or may become payable to our named executive officers that is based on or otherwise relates to the Merger (the " Merger-Related Named Executive Officer Compensation Proposal "), as disclosed pursuant to Item 402(t) of Regulation S-K in " The Merger—Interests of Our Directors and Executive Officers in the Merger—Quantification of Payments and Benefits to Our Named Executive Officers " beginning on page 60 of this proxy statement.

Recommendation of the Company Board

        After careful review and consideration, the Company Board, upon the unanimous recommendation of an independent committee of the Company Board, unanimously determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are fair to, and in the best interests of, the Company and its stockholders. After such consideration, the Company Board approved the Merger Agreement and authorized and approved the Merger upon the terms and conditions set forth in the Merger Agreement.

         Subject to the terms and conditions of the Merger Agreement, the Company Board unanimously recommends that Newport's stockholders vote "FOR" the Merger Proposal, "FOR" the Adjournment Proposal and "FOR" the Merger-Related Named Executive Officer Compensation Proposal. See the

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section entitled " The Merger—Recommendation of the Company Board; Our Reasons for the Merger " beginning on page 40 of this proxy statement.

Stockholders Entitled to Vote; Record Date

        You may vote at the special meeting if you were a record holder of shares of Company Common Stock on March 21, 2016, the record date for the determination of stockholders entitled to notice of and to vote at the special meeting (the " Record Date "). For each share of Company Common Stock that you owned on the Record Date, you are entitled to cast one vote on each matter voted upon at the special meeting. As of the Record Date, there were 38,879,965 shares of Company Common Stock outstanding and entitled to vote.

Quorum and Vote Required

        A quorum of stockholders is necessary to hold the special meeting. The required quorum for the transaction of business at the special meeting shall exist when the holders of a majority of the shares of Company Common Stock entitled to vote at the special meeting are either present in person or represented by proxy. If a quorum is not present at the special meeting, we expect that the special meeting will be adjourned to solicit additional proxies. Abstentions count as shares present for establishing a quorum. Broker non-votes count as shares present for establishing a quorum if the beneficial owner whose failure to provide voting instructions with respect to a particular proposal has resulted in such broker non-vote has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting. Otherwise, broker non-votes do not count as shares present for establishing a quorum.

        You may vote " FOR " or " AGAINST ," or you may " ABSTAIN " from voting on, the Merger Proposal. Approval of the Merger Proposal requires the affirmative vote of the holders of a majority of the outstanding shares of Company Common Stock entitled to vote. Because the vote on the Merger Proposal is based on the total number of shares outstanding, abstentions and "broker non-votes" will have the same effect as voting against the approval of the Merger Proposal. A "broker non-vote" occurs with respect to a particular proposal when a nominee holding shares for a beneficial owner returns a valid proxy but does not vote on such because the broker, bank or other nominee does not have discretionary voting authority with respect to such proposal and has not received instructions from the beneficial owner of the shares with respect to such proposal. Brokers, banks and other nominees will not have discretionary authority on the Merger Proposal, the Adjournment Proposal or the Merger-Related Named Executive Officer Compensation Proposal.

        You may vote " FOR " or " AGAINST ," or you may " ABSTAIN " from voting on, the Adjournment Proposal. The Adjournment Proposal will be approved if a majority of the shares of Company Common Stock, present in person or represented by proxy and entitled to vote at the special meeting, vote in favor of the proposal, whether or not a quorum is present. Abstentions will have the same effect as voting " AGAINST " the approval of the Adjournment Proposal. A broker non-vote with respect to the Adjournment Proposal will have no effect on the outcome of the Adjournment Proposal (unless the beneficial owner whose failure to provide voting instructions with respect to the Adjournment Proposal has resulted in such broker non-vote has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting, in which case such failure to provide such voting instructions with respect to the Adjournment Proposal will have the same effect as voting " AGAINST " the Adjournment Proposal).

        You may vote " FOR " or " AGAINST ," or you may " ABSTAIN " from voting on, the Merger-Related Named Executive Officer Compensation Proposal. The non-binding, advisory Merger-Related Named Executive Officer Compensation Proposal will be approved if a majority of the shares of Company Common Stock, present in person or represented by proxy and entitled to vote on the

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Merger-Related Named Executive Officer Compensation Proposal, vote in favor of the proposal. Abstentions will have the same effect as voting " AGAINST " the approval of the Merger-Related Named Executive Officer Compensation Proposal. A broker non-vote with respect to the Named Executive Officer Compensation Proposal will have no effect on the outcome of the Named Executive Officer Compensation Proposal (unless the beneficial owner whose failure to provide voting instructions with respect to the Named Executive Officer Compensation Proposal has resulted in such broker non-vote has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting, in which case such failure to provide such voting instructions with respect to the Named Executive Officer Compensation Proposal will have the same effect as voting " AGAINST " the Named Executive Officer Compensation Proposal).

Shares Owned by Our Directors and Executive Officers

        As of the Record Date, our directors and executive officers were entitled to vote approximately 728,556 shares of Company Common Stock, or approximately 1.87% of total Company Common Stock outstanding on that date. These numbers do not give effect to outstanding Company RSUs, which are not entitled to vote at the special meeting. Our directors and executive officers have each entered into a stockholder agreement (collectively, the " Stockholder Agreements ") with Parent. Each Stockholder Agreement (i) requires the applicable stockholder to vote such stockholder's shares of Company Common Stock in favor of (and to grant a proxy to Parent to vote in favor of) adoption and approval of the Merger Agreement and to vote against the approval or adoption of any alternative acquisition proposal and (ii) prohibits the applicable stockholder from transferring such stockholder's shares of Company Common Stock, each subject to the exceptions described in the Stockholder Agreement. A copy of the form of Stockholder Agreement is attached to this proxy statement as Annex B. We currently expect that each of our directors and executive officers will vote their shares in favor of the proposals to be presented at the special meeting, in accordance with the terms of the Stockholder Agreements.

Voting; Proxies

        You may vote in person or by proxy at the special meeting.

Voting in Person

        If you plan to attend the special meeting and wish to vote in person, you will be given a ballot at the special meeting. Please note, however, that if you hold your shares of Company Common Stock in "street name," which means your shares are held of record by a broker, bank or other nominee, and you wish to vote at the special meeting, you must bring to the special meeting a legal proxy from the record holder of the shares (your broker, bank or other nominee) authorizing you to vote at the special meeting.

Voting by Proxy

        If you do not wish to attend the special meeting, you may submit your proxy by completing, dating, signing and returning the enclosed proxy card by mail or by granting a proxy electronically via the Internet or by telephone by following the instructions on the enclosed proxy card. All shares of Company Common Stock represented by properly executed proxies received in time for the special meeting will be voted at the special meeting in the manner specified by the stockholders giving those proxies. Properly executed proxies that do not contain voting instructions will be voted " FOR " the Merger Proposal, " FOR " the Adjournment Proposal, and " FOR " the Merger-Related Named Executive Officer Compensation Proposal.

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        Only shares of Company Common Stock affirmatively voted for the Merger Proposal, the Adjournment Proposal, and the Merger-Related Named Executive Officer Compensation Proposal, and properly executed proxies that do not contain voting instructions, will be counted as votes " FOR " the proposals. Shares of Company Common Stock held by persons who attend the special meeting but abstain from voting in person or by proxy, and shares of Company Common Stock for which we received proxies directing an abstention, will be counted for purposes of determining whether a quorum exists, and will have the same effect as votes " AGAINST " the Merger Proposal, the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal. Shares of Company Common Stock represented by proxies that reflect a "broker non-vote" with respect to a particular proposal will not be counted for purposes of determining whether a quorum exists (unless the beneficial owner of such shares has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting, in which case such shares will be counted for purposes of determining whether a quorum exists) and will have the same effect as votes " AGAINST " the Merger Proposal, but will have no effect on the outcome of the Adjournment Proposal or the outcome of the Merger-Related Named Executive Officer Compensation Proposal (unless, in the case of each of the Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal, the beneficial owner of such shares has instructed such beneficial owner's nominee how to vote with respect to at least one other proposal to be voted on at the special meeting, in which case such shares will have the same effect as votes " AGAINST " the Adjournment Proposal or the Merger-Related Named Executive Officer Compensation Proposal, as applicable).

Revocation of Proxy

        If you are a stockholder of record, you may revoke your proxy at any time before your proxy is voted at the special meeting by taking any of the following actions:

•

delivering to our corporate secretary a signed written notice of revocation, bearing a date later than the date of the proxy, stating that the proxy is revoked;



•

signing and delivering a new paper proxy, relating to the same shares and bearing a later date than the original proxy;



•

submitting another proxy by telephone or over the Internet by 11:59 p.m. Eastern time, on the date prior to the date of the special meeting (your latest telephone or Internet voting instructions submitted by such time are followed); or



•

attending the special meeting and voting in person, although attendance at the special meeting will not, by itself, revoke a proxy.

        Written notices of revocation and other communications with respect to the revocation of Newport proxies should be addressed to:

Newport Corporation
1791 Deere Avenue
Irvine, CA 92606
Attention: Corporate Secretary

        If your shares are held in "street name," you may change your vote by submitting new voting instructions to your broker, bank or other nominee. You must contact your broker, bank or other nominee to find out how to do so. If your shares are held in "street name" and you wish to vote at the special meeting in person, you must bring to the special meeting a legal proxy from the record holder of the shares (your broker, bank or other nominee) authorizing you to vote at the special meeting.

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Solicitation of Proxies

        The Company Board is soliciting proxies for the special meeting from our stockholders. We will bear the entire cost of soliciting proxies from our stockholders. In addition to the solicitation of proxies by delivery of this proxy statement by mail, we will request that brokers, banks and other nominees that hold shares of Company Common Stock, which are beneficially owned by our stockholders, send Notices of Special Meeting, proxies and proxy materials to those beneficial owners and secure those beneficial owners' voting instructions. We will reimburse those record holders for their reasonable expenses. We have engaged MacKenzie Partners, Inc. to assist in the solicitation of proxies and provide related advice and informational support for a fee of approximately $50,000, plus reimbursement of customary disbursements. In addition, our directors, officers and employees may also solicit proxies by personal interview, mail, e-mail, telephone, facsimile or by other means of communication. Our directors, officers and employees will not be paid any remuneration for their solicitation efforts, but we will reimburse them for their out-of-pocket expenses.

Dissenters' Rights

        Under Section 92A.390 of the Nevada Revised Statutes (the " NRS "), when the merger consideration is cash, there is no right of dissent with respect to a plan of merger, conversion or exchange in favor of stockholders of any class or series that is a "covered security" under Section 18(b)(l)(A) or (B) of the Securities Act. The shares of Company Common Stock are covered securities because they are traded on NASDAQ. Because the Company Common Stock was listed on NASDAQ on the Record Date and the merger consideration is cash, holders of shares of Company Common Stock will not have dissenters' rights in connection with the Merger.

Adjournments or Postponements

        Although it is not currently expected, the special meeting may be postponed or adjourned for the purpose of, among other things, soliciting additional proxies, by the vote of the holders of a majority of the shares of Company Common Stock represented at the meeting, whether or not a quorum is present. Any signed proxies received by us for which no voting instructions are provided on such matter will be voted " FOR " the Adjournment Proposal.

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be Held on April 27, 2016

        A copy of this proxy statement is available, without charge, by written request to Newport Corporation (Attn: Investor Relations, 1791 Deere Avenue, Irvine, CA 92606) or MacKenzie Partners, Inc. (at the address listed below), or from the SEC website at www.sec.gov.

Assistance

        If you need assistance in completing your proxy card, require additional copies of the enclosed proxy card or have questions regarding the special meeting, please contact our proxy solicitor, MacKenzie Partners, Inc., at:

Call Collect: (212) 929-5500
Toll Free: (800) 322-2885
Email to: proxy@mackenziepartners.com
Address: 105 Madison Avenue, New York, New York 10016

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