Amendment No. 4 to Term Loan Credit Agreement, dated as of April 11, 2018, among the Company, the other loan parties party thereto, Barclays Bank PLC, as administrative agent and collateral agent, and each participating lender party thereto

Exhibit 10.1

Execution Version

AMENDMENT NO. 4 TO TERM LOAN CREDIT AGREEMENT

dated as of

April 11, 2018,

among

MKS INSTRUMENTS, INC.,

as the Borrower,

the other Loan Parties party hereto,

the Participating Lenders party hereto,

and

BARCLAYS BANK PLC,

as Administrative Agent, Lead Arranger and Bookrunner

AMENDMENT NO. 4 TO TERM LOAN CREDIT AGREEMENT

This AMENDMENT NO. 4 TO TERM LOAN CREDIT AGREEMENT, dated as of April 11, 2018 (this “Agreement”), by and among MKS Instruments, Inc., a Massachusetts corporation (the “Borrower”), the other Loan Parties party hereto, Barclays Bank PLC, as the administrative agent and the collateral agent (in such capacity, the “Administrative Agent”) under the Credit Agreement referred to below, and each Participating Lender (as defined below) party hereto.

RECITALS:

WHEREAS, reference is made to the Term Loan Credit Agreement, dated as of April 29, 2016 (as amended by Amendment No. 1 to Term Loan Credit Agreement, dated as of June 9, 2016, among the Borrower, the Loan Parties party thereto, the Administrative Agent and the other parties thereto, by Amendment No. 2 to Term Loan Credit Agreement, dated as of December 14, 2016, among the Borrower, the Loan Parties party thereto, the Administrative Agent and the other parties thereto, and by Amendment No. 3 to Term Loan Credit Agreement, dated as of July 6, 2017, among the Borrower, the Loan Parties party thereto, the Administrative Agent and the other parties thereto, and as many be further amended, restated, amended and restated, supplemented or otherwise modified from time to time, the “Credit Agreement”), among the Borrower, the Lenders from time to time party thereto and the Administrative Agent (capitalized terms used but not defined herein having the meaning provided in the Credit Agreement), pursuant to which the Lenders provided the Borrower with Term Loans in an aggregate initial principal amount of $780,000,000 (the “Initial Term Loans”);

WHEREAS, this Agreement constitutes a Refinancing Amendment, and the Borrower is hereby notifying the Administrative Agent that it is requesting the establishment of Other Term Commitments and/or Other Term Loans, in each case, pursuant to Section 2.15 of the Credit Agreement;

WHEREAS, the Borrower requests Other Term Loans in an aggregate principal amount of $348,463,687.50 (the “Tranche B-4 Term Loans”; the commitments in respect of such Tranche B-4 Term Loans, the “Tranche B-4 Term Commitments”; and the Participating Lenders with Tranche B-4 Term Commitments and any permitted assignees thereof, the “Tranche B-4 Lenders”), which will be available on the Amendment No. 4 Effective Date (as defined below) to refinance all existing Tranche B-3 Term Loans outstanding under the Credit Agreement immediately prior to effectiveness of this Agreement (the “Existing Loans”) and which Tranche B-4 Term Loans shall constitute Other Term Loans and Term Loans (as applicable) for all purposes of the Credit Agreement and the other Loan Documents; it being understood that the aggregate principal amount of the Existing Loans immediately prior to effectiveness of this Agreement is $348,463,687.50;

WHEREAS, each Lender holding Existing Loans under the Credit Agreement immediately prior to effectiveness of this Agreement (each, an “Existing Lender”) executing and delivering a notice of participation in the Tranche B-4 Term Loans in the form attached as Exhibit A hereto (a “Tranche B-4 Participation Notice”) and electing the cashless settlement option therein (each such Lender in such capacity and with respect to the Existing Loans so elected, a “Converting Lender” and, together with each other Person executing and delivering a Tranche B-4 Participation Notice or otherwise providing a Tranche B-4 Term Commitment, the “Participating Lenders”) shall be deemed to have exchanged on the Amendment No. 4 Effective Date the aggregate outstanding principal amount of its Tranche B-3 Term Loans under the Credit Agreement for an equal aggregate principal amount of Tranche B-4 Term Loans under the Credit Agreement;

WHEREAS, the Borrower has appointed Barclays to act, and Barclays agrees to act, as lead arranger and bookrunner in respect of the Tranche B-4 Term Loans;

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WHEREAS, Barclays, in its capacity as lead arranger and bookrunner (the “Lead Arranger”), agrees to act as fronting bank for the syndication of the Tranche B-4 Term Loans (in such capacity, the “Fronting Bank”), the Fronting Bank will purchase, and the Existing Lenders will sell to the Fronting Bank, immediately prior to effectiveness of this Agreement, (i) Tranche B-3 Term Loans of Existing Lenders that do not execute and deliver a Tranche B-4 Participation Notice (the “Non-Participating Lenders”) and (ii) Tranche B-3 Term Loans of Existing Lenders that execute and deliver a Tranche B-4 Participation Notice and elect the cash settlement option therein (the “Non-Converting Lenders”) (the Loans described in the foregoing clauses (i) and (ii), collectively, the “Reallocated Loans”);

WHEREAS, to the extent there exist any Reallocated Loans, the Fronting Bank shall be deemed to exchange on the Amendment No. 4 Effective Date such Reallocated Loans on a cashless settlement basis for an equal aggregate principal amount of Tranche B-4 Term Loans under the Credit Agreement, and such Reallocated Loans shall promptly thereafter be purchased by Participating Lenders (other than Existing Lenders) (the “New Lenders”), Non-Converting Lenders, and Existing Lenders purchasing additional Tranche B-4 Term Loans, each in accordance with such Participating Lenders’ respective Tranche B-4 Participation Notice and as allocated by the Lead Arranger (with the consent of the Borrower, not to be unreasonably withheld or delayed); and

WHEREAS, contemporaneously with the effectiveness of the Tranche B-4 Term Commitments the Borrower wishes to (a) make certain amendments to the Credit Agreement to provide for the incurrence of the Tranche B-4 Term Loans and (b) make certain other modifications to the Credit Agreement set forth herein.

NOW, THEREFORE, in consideration of the premises and agreements, provisions and covenants herein contained, the parties hereto agree as follows:

“Amendment No. 4” shall mean Amendment No. 4 to this Agreement, dated as of April 11, 2018, among the Borrower, the other Loan Parties party thereto, the Lenders party thereto, and the Administrative Agent.

“Amendment No. 4 Effective Date” shall mean the “Amendment No. 4 Effective Date” under and as defined in Amendment No. 4.

“Benefit Plan” shall mean any of (a) an “employee benefit plan” (as defined in ERISA) that is subject to Title I of ERISA, (b) a “plan” as defined in Section 4975 of the Code or (c) any Person whose assets include (for purposes of ERISA Section 3(42) or otherwise for purposes of Title I of ERISA or Section 4975 of the Code) the assets of any such “employee benefit plan” or “plan”.

“PTE” shall mean prohibited transaction class exemption issued by the U.S. Department of Labor, as any such exemption may be amended from time to time.

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“Tranche B-4 Commitments” shall mean the “Tranche B-4 Term Commitments” as defined in Amendment No. 4.

“Tranche B-4 Term Loans” shall mean the “Tranche B-4 Term Loans” as defined in Amendment No. 4.

“ “Applicable Margin” means a percentage per annum equal to (i) for Tranche B-4 Term Loans that are Eurodollar Loans, 1.75% and (ii) for Tranche B-4 Term Loans that are Base Rate Loans, 0.75%.”.

“ “Term Lender” means, collectively, (x) prior to the Amendment No. 4 Effective Date, each Lender identified on Schedule 2.01 as having a Term Commitment on the Closing Date and the “Tranche B-3 Lenders” under Amendment No. 3, (y) on and after the Amendment No. 4 Effective Date, the “Tranche B-4 Lenders” under Amendment No. 4, and (z) each Eligible Assignee which acquires a Term Loan pursuant to Section 10.06(b) and their respective permitted successors, in each case, other than any such Person that has ceased to be a party hereto pursuant to an Assignment and Assumption, Amendment No. 1, Amendment No. 2, Amendment No. 3 or Amendment No. 4”.

“; provided that from and after the effectiveness of Amendment No. 4, “Term Loans” shall mean all Tranche B-4 Term Loans made on the Amendment No. 4 Effective Date (through exchange or otherwise) pursuant to Amendment No. 4.”.

“Subject solely to the terms and conditions set forth herein, each Term Lender severally agrees to make a Term Loan to the Borrower in Dollars on the Closing Date in a principal amount equal to its Term Commitment. The Term Borrowing shall be made from the several Term Lenders ratably in proportion to their respective Term Commitments. The Term Commitments are not revolving in nature, and amounts repaid or prepaid prior to the Maturity Date may not be reborrowed. The Term Commitments shall terminate automatically immediately after the making of the Term Loans on the Closing Date (and for the avoidance of doubt, any Term Commitments not funded on the Closing Date will be terminated). Subject to the terms and conditions hereof and of Amendment No. 1, each Lender with a Tranche B-1 Commitment severally made or exchanged, as applicable, on the Amendment No. 1 Effective Date, a Tranche B-1 Term Loan to the Borrower in Dollars in an amount equal to such Lender’s Tranche B-1 Commitment. The aggregate principal amount of Tranche B-1 Commitments as of the Amendment No. 1 Effective Date for all Lenders was $730,000,000. For the avoidance of doubt, the Borrower made one borrowing under the Tranche B-1 Commitments, which was on the Amendment No. 1 Effective Date,

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and each Lender’s Tranche B-1 Commitment terminated immediately and without further action on the Amendment No. 1 Effective Date after giving effect to the funding of such Lender’s Tranche B-1 Commitment on such date. Subject to the terms and conditions hereof and of Amendment No. 2, each Lender with a Tranche B-2 Commitment severally made or exchanged, as applicable, on the Amendment No. 2 Effective Date, a Tranche B-2 Term Loan to the Borrower in Dollars in an amount equal to such Lender’s Tranche B-2 Commitment. The aggregate principal amount of Tranche B-2 Commitments as of the Amendment No. 2 Effective Date for all Lenders was $628,175,000. For the avoidance of doubt, the Borrower made one borrowing under the Tranche B-2 Commitments, which was on the Amendment No. 2 Effective Date, and each Lender’s Tranche B-2 Commitment terminated immediately and without further action on the Amendment No. 2 Effective Date after giving effect to the funding of such Lender’s Tranche B-2 Commitment on such date. Subject to the terms and conditions hereof and of Amendment No. 3, each Lender with a Tranche B-3 Commitment severally made or exchanged, as applicable, on the Amendment No. 3 Effective Date, a Tranche B-3 Term Loan to the Borrower in Dollars in an amount equal to such Lender’s Tranche B-3 Commitment. The aggregate principal amount of Tranche B-3 Commitments as of the Amendment No. 3 Effective Date for all Lenders was $573,463,687.50. For the avoidance of doubt, the Borrower made one borrowing under the Tranche B-3 Commitments, which was on the Amendment No. 3 Effective Date, and each Lender’s Tranche B-3 Commitment terminated immediately and without further action on the Amendment No. 3 Effective Date after giving effect to the funding of such Lender’s Tranche B-3 Commitment on such date. Subject to the terms and conditions hereof and of Amendment No. 4, each Lender with a Tranche B-4 Commitment severally agrees to make and/or exchange, on the Amendment No. 4 Effective Date, a Tranche B-4 Term Loan to the Borrower in Dollars in an amount equal to such Lender’s Tranche B-4 Commitment. The aggregate principal amount of Tranche B-4 Commitments as of the Amendment No. 4 Effective Date for all Lenders is $348,463,687.50. The Borrower may make only one borrowing under the Tranche B-4 Commitments, which shall be on the Amendment No. 4 Effective Date. Each Lender’s Tranche B-4 Commitment shall terminate immediately and without further action on the Amendment No. 4 Effective Date after giving effect to the funding of such Lender’s Tranche B-4 Commitment on such date.”.

“If at any time the Administrative Agent determines (which determination shall be conclusive absent manifest error) that (i) the circumstances set forth in Section 3.03 have arisen and such circumstances are unlikely to be temporary or (ii) the circumstances set forth in Section 3.03 have not arisen but the supervisor for the administrator of the Eurodollar Rate or a Governmental Authority having jurisdiction over the Administrative Agent has made a public statement identifying a specific date after which the Eurodollar Rate shall no longer be used for determining interest rates for loans, then the Administrative Agent and the Borrower shall endeavor to establish an alternate rate of interest to the Eurodollar Rate that gives due consideration to the then prevailing market

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convention for determining a rate of interest for syndicated loans in the United States at such time, and shall enter into an amendment to this Agreement to reflect such alternate rate of interest and such other related changes to this Agreement as may be applicable. Notwithstanding anything to the contrary in Section 10.01, such amendment shall become effective without any further action or consent of any other party to this Agreement so long as the Administrative Agent shall not have received, within five (5) Business Days of the date notice of such alternate rate of interest is provided to the Lenders, a written notice from the Required Lenders stating that such Required Lenders object to such amendment. Provided that, if such alternate rate of interest shall be less than zero, such rate shall be deemed to be zero for the purposes of this Agreement.”

“9.14    Certain ERISA Matters.

(a)    Each Lender (x) represents and warrants, as of the date such Person became a Lender party hereto, to, and (y) covenants, from the date such Person became a Lender party hereto to the date such Person ceases being a Lender party hereto, for the benefit of, the Administrative Agent and the Arrangers and their respective Affiliates, and not, for the avoidance of doubt, to or for the benefit of the Borrower or any other Loan Party, that at least one of the following is and will be true:

(i)    such Lender is not using “plan assets” (within the meaning of 29 CFR § 2510.3-101, as modified by Section 3(42) of ERISA) of one or more Benefit Plans in connection with the Term Loans or the Term Commitments,

(ii)    the transaction exemption set forth in one or more PTEs, such as PTE 84-14 (a class exemption for certain transactions determined by independent qualified professional asset managers), PTE 95-60 (a class exemption for certain transactions involving insurance company general accounts), PTE 90-1 (a class exemption for certain transactions involving insurance company pooled separate accounts), PTE 91-38 (a class exemption for certain transactions involving bank collective investment funds) or PTE 96-23 (a class exemption for certain transactions determined by in-house asset managers), is applicable with respect to such Lender’s entrance into, participation in, administration of and performance of the Term Loans and the Term Commitments and this Agreement,

(iii)    (A) such Lender is an investment fund managed by a “Qualified Professional Asset Manager” (within the meaning of Part VI of PTE 84-14), (B) such Qualified Professional Asset Manager made the investment decision on behalf of such Lender to enter into, participate in, administer and perform the Term Loans and the Term Commitments and this Agreement, (C) the entrance into, participation in, administration of and performance of the Term Loans and the Term Commitments and this Agreement satisfies the requirements of sub-sections (b) through (g) of Part I of PTE 84-14 and (D) to the best knowledge of such Lender, the requirements of subsection (a) of Part I of PTE 84-14 are satisfied with respect to such Lender’s entrance into, participation in, administration of and performance of the Term Loans and the Term Commitments and this Agreement, or

(iv)    such other representation, warranty and covenant as may be agreed in writing between the Administrative Agent, in its sole discretion, and such Lender.

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(b)    In addition, unless sub-clause (i) in the immediately preceding clause (a) is true with respect to a Lender or such Lender has not provided another representation, warranty and covenant as provided in sub-clause (iv) in the immediately preceding clause (a), such Lender further (x) represents and warrants, as of the date such Person became a Lender party hereto, to, and (y) covenants, from the date such Person became a Lender party hereto to the date such Person ceases being a Lender party hereto, for the benefit of, the Administrative Agent and the Arrangers and their respective Affiliates, and not, for the avoidance of doubt, to or for the benefit of the Borrowers or any other Loan Party, that:

(i)    none of the Administrative Agent or the Arrangers or any of their respective Affiliates is a fiduciary with respect to the assets of such Lender (including in connection with the reservation or exercise of any rights by the Administrative Agent under this Agreement, any Loan Document or any documents related to hereto or thereto),

(ii)    the Person making the investment decision on behalf of such Lender with respect to the entrance into, participation in, administration of and performance of the Term Loans, the Term Commitments and this Agreement is independent (within the meaning of 29 CFR § 2510.3-21) and is a bank, an insurance carrier, an investment adviser, a broker-dealer or other person that holds, or has under management or control, total assets of at least $50 million, in each case as described in 29 CFR § 2510.3-21(c)(1)(i)(A)-(E),

(iii)    the Person making the investment decision on behalf of such Lender with respect to the entrance into, participation in, administration of and performance of the Term Loans, the Term Commitments and this Agreement is capable of evaluating investment risks independently, both in general and with regard to particular transactions and investment strategies (including in respect of the Obligations),

(iv)    the Person making the investment decision on behalf of such Lender with respect to the entrance into, participation in, administration of and performance of the Term Loans, the Term Commitments and this Agreement is a fiduciary under ERISA or the Code, or both, with respect to the Term Loans, the Term Commitments and this Agreement and is responsible for exercising independent judgment in evaluating the transactions hereunder, and

(v)    no fee or other compensation is being paid directly to the Administrative Agent or the Arrangers or any their respective Affiliates for investment advice (as opposed to other services) in connection with the Term Loans, the Term Commitments or this Agreement.

(c)    The Administrative Agent and the Arrangers hereby inform the Lenders that each such Person is not undertaking to provide impartial investment advice, or to give advice in a fiduciary capacity, in connection with the transactions contemplated hereby, and that such Person has a financial interest in the transactions contemplated hereby in that such Person or an Affiliate thereof (i) may receive interest or other payments with respect to the Term Loans, the Term Commitments and this Agreement, (ii) may recognize a gain if it extended the Term Loans or the Term Commitments for an amount less than the amount being paid for an interest in the Term Loans or the Term Commitments by such Lender or (iii) may receive fees or other payments in connection with the transactions contemplated hereby, the Loan Documents or otherwise, including structuring fees, commitment fees, arrangement fees, facility fees, upfront fees, underwriting fees, ticking fees, agency fees, administrative agent or collateral agent fees, utilization fees, minimum usage fees, letter of

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credit fees, fronting fees, deal-away or alternate transaction fees, amendment fees, processing fees, term out premiums, banker’s acceptance fees, breakage or other early termination fees or fees similar to the foregoing.”

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[Signature Pages Follow]

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IN WITNESS WHEREOF, each of the undersigned has caused its duly authorized officer to execute and deliver this Agreement as of the date first set forth above.

[Signature Page to Amendment No. 4 to Term Loan Credit Agreement]

[Signature Page to Amendment No. 4 to Term Loan Credit Agreement]

[Signature Page to Amendment No. 4 to Term Loan Credit Agreement]

EXHIBIT A

Form of Tranche B-4 Participation Notice

Date: April [_], 2018

Barclays Bank PLC, as Administrative Agent

745 7^th Avenue

New York NY 10019

Attn: Robert Walsh

Phone: (212) 526 6047

Email: ***@***

MKS Instruments, Inc.

Tranche B-4 Participation Notice

Ladies and Gentlemen:

Reference is made to Amendment No. 4 (the “Amendment”) to that certain Term Loan Credit Agreement, dated as of April 29, 2016 (as amended by Amendment No. 1 (as defined therein), Amendment No. 2 (as defined therein), Amendment No. 3 (as defined therein) and the Amendment, and as may be further amended, restated, amended and restated, supplemented or otherwise modified from time to time, the “Credit Agreement”), by and among MKS Instruments, Inc., a Massachusetts corporation (the “Borrower”), the Lenders from time to time party thereto, and Barclays Bank PLC, as administrative agent (in such capacity, the “Administrative Agent”). Unless otherwise specified herein, capitalized terms used but not defined herein are used as defined in the Amendment.

By delivery of this letter agreement (this “Tranche B-4 Participation Notice”), each of the undersigned (each a “Participating Lender”), hereby irrevocably consents to the Amendment and the amendment of the Credit Agreement contemplated thereby and (check as applicable):

NAME OF PARTICIPATING LENDER: _____________________________________________

AMOUNT OF EXISTING LOANS OF SUCH PARTICIPATING LENDER: $____________________

[Signature Page Follows]

ANNEX I

REALLOCATED LOANS