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HALE AND DORR LLP
COUNSELLORS AT LAW
WWW.HALEDORR.COM
60 STATE STREET O BOSTON, MA 02109
617-526-6000 O FAX 617-526-5000
Exhibit 8.1
November 9, 2000
MKS Instruments, Inc.
Six Shattuck Road
Andover, MA 01810
Re: Merger pursuant to Agreement and Plan of Merger among
MKS Instruments, Inc., Mango Subsidiary Corp. and
Applied Science and Technology, Inc.
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Ladies and Gentlemen:
This opinion is being delivered to you in connection with the filing of a
registration statement (the "Registration Statement") on Form S-4, which
includes the Proxy Statement and Prospectus relating to the Agreement and Plan
of Merger dated as of October 2, 2000, (the "Merger Agreement"), by and among
MKS Instruments, Inc., a Massachusetts corporation ("Parent"), Mango Subsidiary
Corp., a Delaware corporation and wholly owned subsidiary of Parent ("Sub"), and
Applied Science and Technology, Inc., a Delaware corporation ("Target").
Pursuant to the Merger Agreement, Sub will merge with and into Target (the
"Merger"). Except as otherwise provided, capitalized terms not defined herein
have the meanings set forth in the Merger Agreement and the exhibits thereto or
in the letters delivered to Hale and Dorr LLP by Parent and Target containing
certain representations of Parent and Target relevant to this opinion (the
"Representation Letters"). All section references, unless otherwise indicated,
are to the United States Internal Revenue Code of 1986, as amended (the "Code").
In our capacity as counsel to Parent in the Merger, and for purposes of
rendering this opinion, we have examined and relied upon the Registration
Statement, the Merger Agreement and the exhibits thereto, the Representation
Letters, and such other documents as we considered relevant to our analysis. In
our examination of documents, we have assumed the authenticity of original
documents, the accuracy of copies, the genuineness of signatures, and the legal
capacity of signatories.
We have assumed that all parties to the Merger Agreement and to any other
documents examined by us have acted, and will act, in accordance with the terms
of such
BOSTON NEW YORK WASHINGTON RESTON LONDON* OXFORD*
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Hale and Dorr LLP Includes Professional Corporations
*an independent joint venture law firm
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MKS Instruments, Inc.
November 9, 2000
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Merger Agreement and documents and that the Merger will be consummated at the
Effective Time pursuant to the terms and conditions set forth in the Merger
Agreement without the waiver or modification of any such terms and conditions.
Furthermore, we have assumed that all representations contained in the Merger
Agreement, as well as those representations contained in the Representation
Letters, are, and at the Effective Time will be, true and complete in all
material respects, and that any representation made in any of the documents
referred to herein "to the best of the knowledge and belief" (or similar
qualification) of any person or party is, and at the Effective Time will be,
correct without such qualification. We have also assumed that as to all matters
for which a person or entity has represented that such person or entity is not a
party to, does not have, or is not aware of, any plan, intention, understanding,
or agreement, there is no such plan, intention, understanding, or agreement. We
have not attempted to verify independently such representations, but in the
course of our representation, nothing has come to our attention that would cause
us to question the accuracy thereof.
The conclusions expressed herein represent our judgment as to the proper
treatment of certain aspects of the Merger under the income tax laws of the
United States based upon the Code, Treasury Regulations, case law, and rulings
and other pronouncements of the Internal Revenue Service (the "IRS") as in
effect on the date of this opinion. No assurances can be given that such laws
will not be amended or otherwise changed prior to the Effective Time, or at any
other time, or that such changes will not affect the conclusions expressed
herein. Nevertheless, we undertake no responsibility to advise you of any
developments after the Effective Time in the application or interpretation of
the income tax laws of the United States.
Our opinion represents our best judgment of how a court would decide if
presented with the issues addressed herein and is not binding upon either the
IRS or any court. Thus, no assurances can be given that a position taken in
reliance on our opinion will not be challenged by the IRS or rejected by a
court.
This opinion addresses only the specific United States federal income tax
consequences of the Merger set forth below, and does not address any other
federal, state, local, or foreign income, estate, gift, transfer, sales, use, or
other tax consequences that may result from the Merger or any other transaction
(including any transaction undertaken in connection with the Merger). We express
no opinion regarding the tax consequences of the Merger to shareholders of
Target that are subject to special tax rules, and we express no opinion
regarding the tax consequences of the Merger arising in connection with the
ownership of options or warrants for Target stock.
On the basis of, and subject to, the foregoing, and in reliance upon the
representations and assumptions described above, we are of the following
opinion:
1. The Merger will constitute a reorganization within the meaning of Section
368(a); and
2. The discussion under the section "Material United States Federal Income Tax
Considerations of the Merger" in the Registration Statement, subject to the
limitations
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MKS Instruments, Inc.
November 9, 2000
Page 3
and qualifications described therein, accurately describes the material
federal income tax considerations relevant to Target stockholders receiving
Buyer Common Stock in the Merger.
In rendering this opinion, we have assumed that Mintz, Levin, Cohn, Ferris,
Glovsky & Popeo, P.C. has delivered, and has not withdrawn, an opinion that is
substantially similar to this one. No opinion is expressed as to any federal
income tax consequence of the Merger except as specifically set forth herein,
and this opinion may not be relied upon except with respect to the consequences
specifically discussed herein.
This opinion is intended solely for the purpose of inclusion as an exhibit
to the Registration Statement. It may not be relied upon for any other purpose
or by any other person or entity, and may not be made available to any other
person or entity without our prior written consent. We hereby consent to the
filing of this opinion as an exhibit to the Registration Statement and further
consent to the use of our name in the Registration Statement in connection with
references to this opinion and the tax consequences of the Merger. In giving
this consent, however, we do not hereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act of 1933,
as amended.
Very truly yours,
/s/ Hale and Dorr LLP
HALE AND DORR LLP
