SecProbe.io

<DOCUMENT>
<TYPE>LETTER
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>

Via Facsimile
      June 3, 2005
John D. Villas
Chief Financial Officer
Entegris, Inc.
3500 Lyman Boulevard
Chaska, Minnesota 55318

Re:	Entegris, Inc.
	Registration Statement on Form S-4
	File No. 333-124719
	Filed May 10, 2005

Dear Mr. Villas:

      We have reviewed your filing and have the following
comments.
Where indicated, we think you should revise your document in
response
to these comments.  If you disagree, we will consider your
explanation as to why our comment is inapplicable or a revision is
unnecessary.  Please be as detailed as necessary in your
explanation.
In some of our comments, we may ask you to provide us with
information so we may better understand your disclosure.  After
reviewing this information, we may raise additional comments.

      Please understand that the purpose of our review process is
to
assist you in your compliance with the applicable disclosure
requirements and to enhance the overall disclosure in your filing.
We look forward to working with you in these respects.  We welcome
any questions you may have about our comments or any other aspect
of
our review.  Feel free to call us at the telephone numbers listed
at
the end of this letter.

General

1. Where we ask for revisions to your disclosure in one place in
the
registration statement, please make similar revisions in all other
applicable places in the registration statement.

2. We note disclosure on page 35 that Entegris and Mykrolis have a
former commercial relationship.  Please provide the information
required by Items 1005(b) and 1011(a) of Regulation M-A, which are
incorporated by Item 14(b)(7) of Schedule 14A.

Prospectus Cover Page

3. Please disclose that shareholders do not have appraisal rights.

4. In order to enhance the readability of the prospectus cover
page,
please condense the information and use bullet point disclosure.
See
Rule 421(d) of Regulation C.  In this respect, please do not focus
on
the existence of merger subsidiaries here.  Instead, simply state
that the companies will engage in a merger of equals.

5. Because this letter to Entergis and Mykrolis shareholders also
serves as soliciting material, strive for a balanced presentation.
For example, where you include the boards` recommendation,
disclose
with equal prominence that board members will directly benefit
from
the merger.  Make similar revisions in all applicable places in
the
registration statement.  Also, consider eliminating inherently
subjective statements like "we believe that the combined company
will
be a global leader in materials integrity management for the
microelectronics industry."

Questions and Answers About the Merger, page 1

6. You currently repeat information in your Q&A section and your
summary section.  The Q&A should not repeat any information that
appears in the summary, and the summary should not repeat
information
in the Q&A.  For purposes of eliminating redundancies and grouping
like information together, please view your Q&A and summary as one
section.  Also, when revising your disclosure, we strongly suggest
that you discuss only the procedural questions (i.e. voting
procedures, appraisal procedures, merger subsidiary mechanics,
reincorporation, etc.) with short, clear answers in the Q&A, and
place the material, substantive disclosure of the consideration
and
the terms of the merger, including taxation in the summary.

7. Please disclose the anticipated time period between the vote
and
the closing of the merger.

Q: Why are the companies proposing the merger?, page 1

8. Please clarify what you mean by global "leader."  Tell us
supplementally of the basis for your statement.

Q: What will a stockholder receive in the merger?, page 1

9. Please state that Mykrolis stockholders will not know at the
time
they vote on the merger the value of the Entegris shares that they
will receive in the merger since the exchange ratio is fixed.
Please
include a table disclosing the per share value of the Entegris
shares
that Mykrolis stockholders will receive in the merger based upon a
reasonable range of recent prices for the shares. Please disclose
the
total number of shares that may be issued based upon current
outstanding shares of Entegris common stock. Also provide an
example
of the number of shares to be issued on a per share basis using
the
trading price of the securities as of the latest practicable date.

10. Add disclosure that Mykrolis fractional shareholders will
receive
cash in lieu of stock and as a result, will no longer be
shareholders
of the company.  We assume that odd-lot shareholders will be
cashed
out.  If true, provide a statement to this effect or state the
threshold amount of shares that will determine which shareholders
will be cashed out.

Q: What are the material U.S. federal income tax consequences of
the
merger to Entegris and Mykrolis stockholders?, page 7

11. Delete the reference on page 7 "Assuming that they so qualify.
.
. ."  Instead, disclose counsel`s opinion regarding the taxation
of
the merger and identify counsel.

Summary, page 10

12. Please disclose the basis for all of your assertions here and
in
the remainder of the registration statement that you are a leading
provider of materials integrity management products and services.

Opinion of Entegris` Financial Advisor, page 12

13. Disclose here and in the main section, if true, that no
updated
opinion will be obtained.

Conditions to Completion of the Merger, page 14

14. Disclosure here and elsewhere indicates that the merger`s
closing
is conditioned upon receipt of written opinions on tax matters.
Since each party may waive the condition, you must:

* File executed opinions before effectiveness even though the
merger
agreement is conditioned upon the receipt of one or more favorable
tax opinions at closing.

* Undertake to recirculate and resolicit if the condition is
waived
and the change in tax consequences is material.  We note your
disclosure on page 19.

Risk Factors, page 17

We may be unable to successfully integrate our operations..., page
17

15. Please quantify the cost savings you anticipate for the
merger.

Entegris and Mykrolis will incur substantial expenses whether or
not
the merger is completed, page 18

16. Please discuss the expenses in greater detail.  For instance,
do
these costs just include those you have enumerated or do they also
include the costs of implementing the merger and hoped for
synergies.

Failure to complete the merger could negatively affect Entegris`
and
Mykrolis` stock prices, page 18

17. The bulleted points appear to be duplicative of the risks
raised
in the risk factor titled "Entegris and Mykrolis will incur
substantial expenses..."  Please revise to combine.

Uncertainty regarding the merger and the effects of the merger
could
adversely affect each company`s relationships..., page 19

18. In addition to bundling multiple risks, this risk factors
appears
to draw the generic conclusion that it would have a "material
adverse
effect" on your business.  Please revise to state with more
specificity the risks to your financial condition or operations.
Also, you mention your ability retain key management in the
aftermath
of the merger.  To the extent management is aware that this will
occur, please describe.

19. We note that all of the risk factors relate to the
consequences
of the merger or potential for a merger.  Consider risk factors
specifically related to the businesses of Entergis and Mykrolis
after
the merger.

Cautionary Statement Concerning Forward-Looking Statements, page
20

20. The penultimate paragraph in this section is overly broad and
inappropriate with respect to the application of cautionary
language
contained in this section to all subsequent statements by the
companies.  Please revise.

21. Refer to your statement that, "Entegris and Mykrolis undertake
no
obligation to update or revise the forward-looking statements,
whether as a result of new information, future events or
otherwise."
Please confirm supplementally that you are aware of your
responsibility to make full and prompt disclosure of material
facts,
both favorable and unfavorable, regarding your financial
condition,
and that this responsibility may extend to situations where
management knows or has reason to know that previously disclosed
projections no longer have a reasonable basis. See Item
10(b)(3)(iii)
of Regulation S-K.

22. To the extent that the proxy statement/prospectus states that
it
includes forward-looking statements within the meaning of the
Private
Securities Litigation Reform Act of 1995, please be advised that
the
staff is not making any determination as to whether the
disclosures
(including, e.g., cautionary language or the placement of
disclosures) satisfy the requirements of such Sections.

Solicitation of Proxies, page 29

23. We note that you may employ various methods to solicit
proxies,
including mail, telephone, personal interviews, or the Internet.
Be
advised that all written soliciting materials, including emails or
scripts to be used soliciting proxies over the telephone, must be
filed under the cover of Schedule 14A.  Please refer to Item 14a-
6(b)
and (c).  Please confirm your understanding.

The Merger, page 35

24. We note statements throughout the document regarding the
boards`
belief that the merger would result in great synergies.  At an
appropriate place, please describe the strategic rationale and the
economic and operational benefits of the merger.  In order for
stockholders to make an educated decision about the merger, you
should explain what the combined company will look like going
forward.  For example, add discussion as to how each company
complements or overlaps each other.  Is each company focused on
the
same markets?  If so, what plans do you have to integrate
operations
or eliminate duplicative functions?   What will the anticipated
synergies and cost savings be?

Background of the Merger, page 35

25. Please disclose prominently that Mykrolis stockholders will
not
be protected against the decline in the price of Entergis` stock
between the time of voting for the merger and the trading day
immediately preceding the date of the merger.  Please disclose any
negotiations for downside protection or the reason for no such
negotiations.

26. We note that a representative of Citigroup Global Markets Inc.
arranged and attended the July 13, 2004 dinner meeting between
Messrs. Dauwalter and Zadel and that Citigroup was not yet
retained
by either party.  Please clarify Citgroup`s role at this meeting.
Disclose which party first initiated contact with Citigroup.

27. We note that in October 2004, Entegris retained Goldman, Sachs
&
Co. as its financial advisor and that Entegris and Goldman agreed
that Goldman would assist Entegris in evaluating three possible
alternative strategic business combinations.  Please describe the
alternatives presented and why Entergis chose the combination with
Mykrolis over the others.  Supplementally, confirm that no offers
were made to combine with Entergis or disclose the amount and form
of
consideration offered and the reasons for rejecting the offer.

28. Please describe the other strategic alternatives that Mykrolis
considered and disclose why it chose to merge with Entergis rather
than peruse these alternatives.  Please clarify the "lack of
compelling product synergies."

29. Please describe how the parties negotiated the exchange ratio.

30. We note your statement that Mykrolis engaged Citigroup as its
financial advisor to assist it in connection with the evaluation
of
strategic alternatives.  However, please clarify that Citigroup`s
opinion was limited to the fairness of the exchange ratio and did
not
consider alternative combinations.

31. Please provide for staff review all materials prepared by
Goldman, and Citigroup provided to Entegris, Mykrolis or their
representatives.  Provide all transcripts, summaries and video
presentation materials as well as copies of board books.  We may
have
further comments upon reviewing these materials.

Recommendation of Mykrolis` Board of Directors; Mykrolis` Reasons
for
the Merger, page 44

32. Please disclose whether the fact that any portion of the
merger
consideration paid in cash could be taxable to holders was
considered
as a risk of the transaction.

Opinion of Entegris` Financial Advisor, page 46

33. Please disclose whether Goldman has provided past services to
Entegris and, if so, how much they were paid in the past two
years.
We note your disclosure in the third full paragraph on page 53.
Please refer to Item 4(b) of Form S-4 and Item 1015 of Regulation
M-
A.

34. Please disclose the basis for Goldman`s assumption that the
financial analyses and forecasts relating to the companies were
reasonably prepared and reflected the best currently available
estimates and judgments of management.  Please apply this to your
disclosure on page 54 regarding Citigroup`s opinion.

35. Please disclose how stockholders are to evaluate the results
of
each analysis in connection with your determination that the
merger
consideration is fair.  For example, how should stockholders
evaluate
a 1.7 X NTM revenue multiple and how should they evaluate results
where the merger consideration is lower in some instances than the
implied ratios or values.  As part of this, compare the results of
your analyses to the per share consideration that will be given in
the merger.

Opinion of Mykrolis` Financial Advisor, page 53

36. We note that Citigroup and its affiliates in the past have
provided services to Mykrolis and Entegris unrelated to the
proposed
merger.  Please disclose how much has been paid to Citigroup in
the
past two years.  . Please refer to Item 4(b) of Form S-4 and Item
1015 of Regulation M-A.

37. With respect to the other analyses and information that you
state
Citigroup conducted in the second paragraph on page 54, please
either
describe these or delete the reference.

Material U.S. Federal Income Tax Consequences, page 74

38. Please explain how this merger qualifies for treatment as a
reorganization within the meaning of Section 368(a) of the
Internal
Revenue Code of 1986.  Please briefly explain the conditions of
Section 368(a).

39. Please revise the last paragraph to state counsels` opinions
regarding taxation of the merger.

Pro Forma Condensed Combined Financial Statements

Note 1 --  Basis of Presentation

Experts

40. We note your reference to the independent valuation
specialists.
Please name these experts and provide their consents as required
by
Section 436(b) of Regulation C or delete your reference to them.

41. Please expand your disclosures to describe the nature of the
developed technology intangible asset you acquired from Mykrolis.

42. We note that you have currently allocated $313 million of the
total estimated purchase price to goodwill.  Expand your
disclosures
to provide a description of the factors that contributed to this
very
significant portion of the purchase price being allocated to
goodwill.

Note 3 - Deferred Stock-Based Compensation

43. You indicate that the deferred compensation "...represents the
estimated intrinsic value of the unvested Mykrolis stock options
assumed and the issuance of restricted stock."  We have the
following
comments regarding this disclosure.

* We assume you have determined the deferred compensation related
to
the intrinsic value of the Entegris stock options issued (i.e. the
replacement awards) in exchange for the Mykrolis stock options.
Please revise your disclosure to clarify.
* Separately disclose the intrinsic value of the unvested Entegris
stock and indicate that this amount is included in your purchase
price allocation.  Separately disclose the value of your
restricted
stock and address your accounting for the restricted stock.
Please
advise or revise your pro formas accordingly.

Exhibits

44. Note that we may have comments on the tax and legality
opinions
and o