Exhibit 10.1

EMPLOYMENT AGREEMENT

EMPLOYMENT AGREEMENT dated August 3, 2012 (“Employment Agreement”), by and
between MKS Instruments, Inc., a Massachusetts Corporation (the “Corporation”),
and Seth Bagshaw of Boxford, MA (the “Employee”).

WHEREAS, the Corporation and the Employee desire to provide for the employment
of the Employee by the Corporation:

NOW, THEREFORE, in consideration of the premises and the mutual promises
contained herein, the Corporation and the Employee hereby agree as follows:

(1) Term of Employment:

(a) The Corporation hereby employs the Employee, and the Employee hereby accepts
employment with the Corporation, for a period commencing as of August 3, 2012
continuing thereafter until terminated as provided in this Section (1) or
Section (5).

(b) The Corporation may terminate Employee’s employment at any time for any
reason, or no reason, by notifying Employee of such termination. The employment
of the Employee under this Employment Agreement shall terminate thirty (30) days
after the date of such notice; provided, however, that the employment of the
Employee under this Employment Agreement is subject to prior termination as
hereinafter provided in Section (5)(b) and (c). Notwithstanding the above, the
Corporation shall be entitled, at its sole discretion, to waive its obligation
to continue active employment of the Employee during the 30 day notice period.
In the event the Corporation elects at any time to waive its obligation to
continue active employment of the Employee during the 30 day notice period, the
Corporation shall continue to pay the Employee his customary Base Salary (as
defined in Section (4)) and will reimburse Employee for the premiums (if any) he
pays for continuation of life insurance should he elect to exercise the
conversion feature (if any) of the Corporation’s group life policy then in
effect and for the premiums ( if any ) for the continuation under the federal
COBRA program of such medical/dental insurance as Employee may then receive
through the balance of the 30 day notice period.

(c) Employee may terminate employment by delivering notice of resignation no
later than thirty (30) days prior to the intended date of termination of
employment (“Resignation Date”); provided, however, that the Corporation may at
any time and for any reason, or no reason, accelerate the Resignation Date to
any date prior thereto up to and including the date Employee delivers such
notice of resignation, which such acceleration shall not, in any event, be
deemed a termination by Corporation of Employee’s employment. Unless the
employment is terminated pursuant to Section (5), the Corporation shall, if it
terminates the employment prior to the Resignation Date, continue to pay
Employee his customary Base Salary (as defined in Section (4)) and will

 

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reimburse Employee for the premiums (if any) he pays for continuation of life
insurance should he elect to exercise the conversion feature (if any) of the
Corporation’s group life policy then in effect and for the premiums ( if any )
for the continuation under the federal COBRA program of such medical/dental
insurance as Employee may then receive, through the balance of the 30 day notice
period.

(2) Capacity: Employee is being paid to perform such duties and exercise such
powers, authorities and discretions in relation to the Corporation as are
customary and incidental to Employee’s position and such other services that are
delegated or assigned to him by the CEO & President of the Corporation or his
designee, including any authorized manager or supervisor of the Employee. It
shall be a condition to Employee’s employment hereunder that Employee execute
and deliver to the Corporation that Confidential Information Agreement of MKS
Instruments, Inc. (“Confidential Information Agreement”) attached hereto as
Attachment 1, and by execution of this Employment Agreement, Employee
(i) acknowledges receipt of the Confidential Information Agreement and
(ii) agrees to be bound by all of the terms of the Confidential Information
Agreement.

(3) Extent of Services: During the term of employment of the Employee under this
Employment Agreement, the Employee shall devote his full time to, and use his
best efforts in the furtherance of, the business of the Corporation and shall
not perform similar duties in any other capacity for any other person or engage
in any other business activity which interferes in any way with the Employee
performance of his duties to the Corporation, whether or not such business
activity is pursued for gain or any other pecuniary advantage, without the prior
written consent of the Corporation. Employee agrees and understands that
Employee owes the Corporation fidelity and loyalty during his term of employment
with the Corporation.

(4) Compensation: In consideration of the services to be rendered by the
Employee under this Employment Agreement, the Corporation agrees to pay, and the
Employee agrees to accept, the following compensation:

(a) Base Salary: A base salary at the rate of three hundred twenty five thousand
dollars and zero cents ($325,000.00) per year for the term of employment of the
Employee under this Employment Agreement. The base salary shall be payable in
equal biweekly installments subject to usual withholding requirements. This
salary will be reviewed regularly according to the practices of the Corporation
and will be subject to any changes in pay policies implemented by the
Corporation from time to time. As an exempt employee, the Employee shall not be
entitled to receive any overtime pay from the Corporation.

(b) MKS Instruments, Inc. Profit Sharing and 401-K Plan: The Employee shall be
eligible to become a participant under the profit sharing plan of the
Corporation on fulfilling the conditions set forth in the MKS Instruments, Inc.
Profit Sharing and 401-K Plan, subject to any changes thereto that may be
implemented from time to time.

(c) Vacation: The Employee shall be entitled to an annual vacation leave of 18
days at full pay during each year of this Employment Agreement, subject to the

 

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Employee arranging such vacation so as not to affect adversely the ability of
the Corporation to transact its business. Such vacation leave shall accrue and
be administered according to the policies and practices of the Corporation.

(d) Life Insurance: The Corporation shall provide and pay such premiums for such
term life insurance for the Employee during the term of employment of the
Employee under this Employment Agreement as may be applicable to the Employee,
subject to any changes in the term life insurance policies that may be
implemented by the Corporation from time to time.

(e) Medical/Dental Insurance: The Corporation shall provide and pay such
premiums for such group medical/dental insurance for the Employee during the
term of employment of the Employee under this Employment Agreement as may be
applicable to the Employee, subject to any changes in the medical/dental
insurance policies that may be implemented by the Corporation from time to time.

(f) Other Benefits: The Corporation shall provide other benefits for the
employee under the Plans of the Corporation applicable to the Employee during
the term of employment of the Employee under this Employment Agreement.

(5) Termination: The employment of the Employee under this Employment Agreement
shall terminate:

(a) On the expiration of the period of employment as provided in Section (1).

(b) Upon the death of the Employee, or the disability of the Employee as defined
in Section (6) (e) below.

(c) Upon Corporation’s delivery of notice of the existence of Cause. “Cause”
shall mean: (i) Employee’s refusal to follow directions from the CEO & President
of the Corporation or his designee that are not inconsistent with Employee’s
position, (ii) Employee’s failure to perform his duties other than as a result
of Disability or death, (iii) Employee’s disregard of or failure to comply with
the Corporation’s directives, policies or procedures other than as a result of
Disability or death, (iv) Employee’s engaging in negligent, reckless or
intentional conduct injurious to the Corporation, any of its subsidiaries or
affiliates or any of its directors or officers, (v) Employee’s conviction of a
felony or a serious misdemeanor or plea of other than “not guilty” to any felony
or serious misdemeanor charge, (vi) Employee’s engaging in conduct that is
injurious to the Corporation’s name or reputation or (vii) Employee’s breach of
this Employment Agreement or the Confidential Information Agreement.

(6) Payment Upon Termination:

(a) If the employment of the Employee is terminated by the Corporation other
than pursuant to Section 5 (c) the Corporation shall continue to pay Employee
the Base Salary in effect immediately prior to the time of such termination (but

 

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without any bonus, commission or other similar amounts except as may have been
earned and due prior to such termination) for six (6) months after the last full
day employee works under this Agreement at its normal payroll payment dates.

(b) If the employment of the Employee is terminated by death, the Corporation
shall pay to the estate of the Employee the compensation which would otherwise
be payable to the Employee at the end of the month in which his death occurs and
other unpaid amounts to which Employee would have been at that time entitled as
an Employee under any applicable compensation or benefit plan or program.

(c) In the event the employment of the Employee is terminated by the Corporation
for Cause pursuant to Section (5) (c) hereof, the Corporation shall have no
obligation to pay the Employee any amounts, except for Base Salary through the
last full day of actual work for the Corporation.

(d) In the event the Employee voluntarily resigns, the Corporation shall have no
obligation to pay the Employee any amounts, except for Base Salary through the
last full day of actual work for the Corporation, or, if applicable, amounts
payable in accordance with Section (1.c), and other unpaid amounts to which
Employee is at that time entitled under any applicable compensation or benefit
plan or program.

(e) If Employee is incapacitated by a physical or mental condition, illness, or
injury that prevents Employee from being able to perform his duties under this
Employment Agreement in a satisfactory manner for substantially all of a twelve
(12) consecutive week period (or such longer period as may be required by law or
that the CEO & President of the Corporation or his designee may, in his
discretion, determine) with any reasonable accommodation that may be required by
law, then Employee shall be deemed to be unable to perform his job (any such
physical or mental condition, illness, or injury, a “Disability”). In such
event, the Corporation may terminate Employee’s employment, in which case
Employee shall receive (i) any accrued but unpaid Base Salary and other unpaid
amounts to which Employee is at that time entitled under any applicable
compensation or benefit plan or program and (ii) all applicable disability
benefits consistent with any applicable benefits program. The Corporation shall
have no further obligations to Employee. Nothing in this paragraph is intended
to or shall operate to excuse the Corporation from any legal obligations it may
have under applicable laws.

(f) The Corporation shall deduct from the amounts payable to Employee pursuant
to this Agreement all required withholding amounts and deductions, including but
not limited to federal, state and local withholding amounts in accordance all
applicable laws and regulations and deductions authorized by Employee. Employee
shall be solely responsible for and shall pay all taxes associated with the
amounts payable under this Agreement

(7) Noncompetition Agreement: Employee shall not, without the written consent of
the Corporation, during the term of employment with the Corporation and for the
period of one year thereafter (the “Non-Compete Period”), engage in or otherwise
carry on, directly or indirectly

 

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anywhere in the world (either as principal, agent, employee, employer, investor,
shareholder (except for holdings of no greater than 1% of the total outstanding
shares in a publicly-traded company), consultant, partner, member, financier or
in any other individual or representative capacity of any kind whatsoever), any
business or activity competitive with the Corporation but solely to the extent
such business or activity is related to, similar to or competitive with the
activities of the business unit(s), division(s), laborator(y)(ies),
facilit(y)(ies) and other operational unit(s) in or for which Employee performed
work for the Corporation or about which Employee acquired Proprietary
Information (as defined in the Confidential Information Agreement). The
Non-Compete Period shall be extended for any period during which Employee is in
breach of this Agreement or the Confidential Information Agreement.

(8) Notice: Any and all notices under this Employment Agreement shall be in
writing and, if to the Corporation, shall be duly given if sent to the
Corporation by registered or certified mail, postage prepaid, return receipt
requested, at the address of the Corporation set forth under its name below or
at such other address as the Corporation may hereafter designate to the Employee
in writing for the purpose, and if to the Employee, shall be duly given if
delivered to the Employee by hand or if sent to the Employee by registered or
certified mail, postage prepaid, return receipt requested, at the address of the
Employee set forth under his name below or at such other address as the Employee
may hereafter designate to the Corporation in writing for the purpose.

(9) Assignment: The rights and obligations of the Corporation under this
Employment Agreement shall inure to the benefit of, and shall be binding upon,
the successors and assigns of the Corporation. The rights and obligations of the
Employee under this Employment Agreement shall inure to the benefit of, and
shall be binding upon, the heirs, executors and legal representatives of the
Employee.

(10) Entire Agreement and Severability:

(a) This Employment Agreement and the Confidential Information Agreement
supersede any and all other agreements, either oral or in writing, between the
parties hereto with respect to the employment of the Employee by the Corporation
and contains all of the covenants and agreements between the parties with
respect to such employment. Each party to this Employment Agreement acknowledges
that no representations, inducements, promises or agreements, oral or otherwise,
have been made by any party, or any one acting on behalf of any party, which are
not embodied herein, and that no other agreement, statement or promise not
contained in this Employment Agreement shall be valid and binding. Any
modification of this Employment Agreement will be effective only if it is in
writing signed by both parties to this Employment Agreement.

(b) If any provision in this Employment Agreement is held by a court of
competent jurisdiction to be invalid, void or unenforceable, the remaining
provisions shall nevertheless continue in full force and effect without being
impaired or invalidated in any way.

(c) All pronouns used herein shall include the masculine, feminine, and neuter
gender as the context requires.

 

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(11) Miscellaneous: This Agreement and the rights and obligations of the parties
hereunder shall be governed by, and construed in accordance with, the laws of
the Commonwealth of Massachusetts, excluding (but only to the extent permitted
by law) its conflict of laws and choice of law rules, and jurisdiction over any
action to enforce this Agreement, or any dispute arising from or relating to
this Agreement shall subsist solely in the state and/or federal courts located
within the Commonwealth of Massachusetts. The parties hereto further agree that
service of any process, summons, notice or document by U.S. certified mail or
overnight delivery by a generally recognized commercial courier service to
Employee’s last known address (or any mode of service recognized to be effective
by applicable law) will be effective service of process for any action, suit or
proceeding brought against Employee in any such court. This Agreement may be
executed in any number of counterparts, each of which, when executed by both
parties to this Agreement shall be deemed to be an original, and all of which
counterparts together shall constitute one and the same instrument. The failure
of either party hereto to enforce any right under this Agreement shall not be
construed to be a waiver of that right, or of damages caused thereby, or of any
other rights under this Agreement.

IN WITNESS WHEREOF, the parties hereto have executed, in the Commonwealth of
Massachusetts, this Employment Agreement as a sealed instrument, all as of the
day, month and year first written above.

 

MKS INSTRUMENTS, INC.      By:  

/s/ Leo Berlinghieri

         Leo Berlinghieri        CEO & President        2 Tech Drive       
Andover, MA 01810       

/s/ Seth H. Bagshaw

  Legal Signature        Seth H. Bagshaw        5 Bayns Hill Road       
Boxford, MA 01921     

 

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