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EXHIBIT 5.1
HALE AND DORR LLP
COUNSELLORS AT LAW
WWW.HALEDORR.COM
60 STATE STREET -- BOSTON, MA 02109
617-526-6000 -- FAX 617-526-5000
July 13, 2000
MKS Instruments, Inc.
Six Shattuck Road
Andover, MA 01810
Re: REGISTRATION STATEMENT ON FORM S-3
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Ladies and Gentlemen:
This opinion is furnished to you in connection with a Registration
Statement on Form S-3 (File No. 333-34450) (the "Registration Statement") filed
with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Securities Act"), for the registration
of an aggregate of 3,000,000 shares of Common Stock, no par value per share (the
"Shares"), of MKS Instruments, Inc., a Massachusetts corporation (the
"Company"), of which (i) 3,000,000 Shares will be issued and sold by the Company
and (ii) the remaining 1,000,000 Shares will be sold by certain stockholders of
the Company (the "Selling Stockholders").
We are acting as counsel for the Company in connection with the
registration of the Shares for sale by the Company and the Selling Stockholders.
We have examined signed copies of the Registration Statement as filed with the
Commission. We have also examined and relied upon minutes of meetings of the
stockholders and the Board of Directors of the Company as provided to us by the
Company, stock record books of the Company as provided to us by the Company, the
Certificate of Incorporation and By-Laws of the Company, each as restated and/or
amended to date, and such other documents as we have deemed necessary for
purposes of rendering the opinions hereinafter set forth.
In our examination of the foregoing documents, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all documents submitted to
us as copies, the authenticity of the originals of such latter documents and the
legal competence of all signatories to such documents.
Our opinion in clause (ii) below, insofar as it relates to the Selling
Stockholders' Shares being fully paid, is based solely on a certificate of the
Chief Financial Officer of the Company confirming the Company's receipt of the
consideration called for by the applicable resolutions authorizing the issuance
of such shares.
BOSTON WASHINGTON, DC NEW YORK RESTON LONDON*
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Hale and Dorr LLP Includes Professional Corporations
*an independent joint venture law firm
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MKS Instruments, Inc.
July 13, 2000
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We assume that the appropriate action will be taken, prior to the offer
and sale of the Shares, to register and qualify the Shares for sale under all
applicable state securities or "blue sky" laws.
We express no opinion herein as to the laws of any state or jurisdiction
other than the state laws of the Commonwealth of Massachusetts and the federal
laws of the United States of America.
Based upon and subject to the foregoing, we are of the opinion that (i)
the Shares to be issued and sold by the Company have been duly authorized for
issuance and, when such Shares are issued and paid for, such Shares will be
validly issued, fully paid and nonassessable and (ii) the Shares to be sold by
the Selling Stockholders have been duly authorized and are validly issued, fully
paid and nonassessable.
It is understood that this opinion is to be used only in connection with
the offer and sale of the Shares while the Registration Statement is in effect.
Please note that we are opining only as to the matters expressly set forth
herein, and no opinion should be inferred as to any other matters. This opinion
is based upon currently existing statutes, rules, regulations and judicial
decisions, and we disclaim any obligation to advise you of any change in any of
these sources of law or subsequent legal or factual developments which might
affect any matters or opinions set forth herein.
We hereby consent to the filing of this opinion with the Commission as an
exhibit to the Registration Statement in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of our
name therein and in the related Prospectus under the caption "Legal Matters." In
giving such consent, we do not hereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act or the
rules and regulations of the Commission.
Very truly yours,
/s/ Hale and Dorr LLP
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Hale and Dorr LLP
