Exhibit 10.1

June 10, 2014

Jon Snodgres

22 Crest Terrace

Montville, NJ 07045

Re: Employment Agreement

Dear Jon:

This letter agreement (the “Agreement”) sets forth the terms of your employment
with Repligen Corporation (the “Company”). This Agreement supersedes any prior
oral or written agreements or understandings related to the terms and conditions
of your employment.

1. Position. Your position with the Company will be Chief Financial Officer and
you will report directly to the Chief Executive Officer of the Company (the
“CEO”). This is a full-time position. While you render services to the Company,
you will not engage in any other employment, consulting or other business
activity (whether full-time or part-time) without prior written approval from
the CEO.

2. Start Date. Your employment will begin on July 14, 2014, unless another date
is mutually agreed upon by you and the Company. For purposes of this Agreement,
the actual first day of your employment shall be referred to as the “Start
Date.”

3. Salary. The Company will pay you a salary at the rate of $320,000 per year
(the “Base Salary”), payable in accordance with the Company’s standard payroll
schedule and subject to applicable deductions and withholdings. Your salary will
be subject to periodic review and adjustments at the Company’s discretion.

4. Annual Bonus. You will be eligible to receive an annual performance bonus
under the Company’s Executive Incentive Compensation Plan (or such other
applicable plan or program adopted by the Company) (the “Bonus Plan”). The
Company will target the bonus at up to 50% of the Base Salary. For 2014, the
target bonus will be prorated at approximately 23.4% based upon your commencing
employment on the date referred to in paragraph 2. The actual bonus percentage
is discretionary and will be subject to the Company’s assessment of your
performance, as well as business conditions at the Company. The bonus also will
be subject to approval by and adjustment at the discretion of the Company’s
board of directors or compensation committee and the terms of the Bonus Plan;
provided that you shall be eligible for a prorated bonus for 2014 based upon the
number of days in 2014 that you work for the Company. The annual performance
bonus, if any, shall be paid between January 1st and March 15th of the calendar
year following the applicable bonus year. You must be employed on the bonus
payment date to earn any part of a bonus.

5. Stock Options and Incentive Grants. The Company shall grant you an incentive
stock option to purchase 10,000 shares of the Company’s Common Stock (the
“Option Grant”) and a restricted stock unit award for 5,000 shares of the
Company’s Common Stock (the “RSU Grant” and collectively with the Option Grant,
the “Equity Awards”)) under the Company’s Amended and Restated 2012 Stock Option
and Incentive Plan (the “Plan”). The foregoing options shall be issued at an
exercise price equal to the fair market value of the Common Stock as determined
by the Company’s board of directors on the date of grant (the “Grant Date”). The
Equity Awards shall vest and become exercisable in equal annual installments on
the first, second, third, fourth and fifth anniversaries of the Grant Date,
respectively, and the Equity Awards shall be further subject to the terms and
conditions set forth in the Plan and the Company’s associated Incentive Stock
Option Agreement and Restricted Stock Unit Award Agreements. In addition, you
will be eligible to receive additional incentive equity awards under the
Company’s executive incentive plans or programs (such plan or program, an “LTI
Plan”). The Company will target the value of any such awards at an aggregate
value of 50% of your total target compensation (presently estimated to be
$240,000) in 2015. Any actual awards under a LTI Plan (“LTI Awards”) are
discretionary and will be subject to the Company’s assessment of your
performance, as well as business conditions at the Company. Any LTI Awards will
be subject to approval by and adjustment at the discretion of the Company’s
board of directors or compensation committee and the terms of any applicable LTI
Plan. As with the Bonus, the Company expects to review your job

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performance on an annual basis and will discuss with you the criteria which the
Company will use to assess your performance for LTI Plan purposes. The Company
also may make adjustments in the targeted amount of any LTI Awards.

6. Benefits. You will be eligible to participate in the employee benefits and
insurance programs generally made available to the Company’s full-time employees
which currently include health, life, short and long-term disability and a
401(k) plan. Details of these benefits programs, including mandatory employee
contributions, and, if applicable, waiting periods, will be made available to
you when you start. You will also be eligible for up to 20 days of Paid Time Off
per year (vacation/personal time) which shall accrue on a prorated basis, in
accordance with the Company’s vacation policy as in effect from time to time.

7. Relocation. The Company will provide you with up to $75,000 to be used in
connection with your relocation of your principal residence from New Jersey to
Massachusetts (“Relocation Amount”). Acceptable uses of the Relocation Amount
include moving expenses and other reasonable move-related items (collectively
“Relocation Expenses”), or other documented associated with buying or selling
your home. Appropriate supporting documentation (i.e., itemized receipts) of the
Relocation Expenses must be submitted within 45 days after the Relocation
Expenses were incurred and prior to reimbursement. The Company will determine in
its reasonable judgment what, if any, of your reimbursed Relocation Expenses are
for nondeductible expenses in accordance with applicable law and will comply
with associated withholding and tax reporting obligations. In the event that, at
any time within 12 months from your Start Date, you resign or you are terminated
by the Company for Cause you agree to reimburse the Company for the portion of
the Relocation Amount paid to you under this provision. In the event that, at
any time after 12 months but before 24 months from your Start Date, you resign
or you are terminated by the Company for Cause you agree to reimburse the
Company for fifty percent (50%) of the Relocation Amount paid to you under this
provision.

8. At-will Employment, Severance. Your employment is “at will,” meaning you or
the Company may terminate it at any time for any or no reason at which time you
will be entitled to Accrued Obligations, defined as (1) the portion of your Base
Salary that has accrued prior to any termination of your employment with the
Company and has not yet been paid, (2) an amount equal to the value of your
accrued unused vacation days and (3) the amount of any expenses properly
incurred by you on behalf of the Company prior to any such termination and not
yet reimbursed and to no other compensation, provided, however, in the event the
Company terminates your employment without Cause (as defined below), in addition
to the Accrued Obligations, the Company shall provide to you the following
termination benefits (the “Termination Benefits”):

(i) continuation of your base salary for a period of 6 months at the rate then
in effect in accordance with the terms of the Company’s standard payroll
schedule (solely for purposes of Section 409A of the Internal Revenue Code of
1986, as amended, each payment is considered a separate payment (“Salary
Continuation Payments”)); and

(ii) continuation of group health plan benefits for a period of 6 months to the
extent authorized by and consistent with 29 U.S.C. § 1161 et seq. (commonly
known as “COBRA”), with the cost of the regular premium for such benefits shared
in the same relative proportion by the Company and you as in effect on the date
of termination.

(iii) full vesting of 50% of the then unvested Equity Awards, provided that you
shall have with 90 days from such termination to exercise the Option Grant.

Notwithstanding anything to the contrary in this Agreement, you shall not be
entitled to any Termination Benefits unless you first (i) enter into, do not
revoke, and comply with the terms of a separation agreement in a form acceptable
to the Company which shall include a release in favor of the Company and related
persons and entities (the “Release”); (ii) resign from any and all positions,
including, without implication of limitation, as a director, trustee, and
officer, that you then hold with the Company and any affiliate of the Company;
and (iii) return all Company property and comply with any instructions related
to deleting and purging duplicates of such Company property. The Salary
Continuation Payments shall commence within 60 days after the date of
termination; provided, however, that if the 60-day period begins in one calendar
year and ends in a second calendar year, the Salary Continuation Payments shall
begin to be paid in the second calendar year. All compensation and benefits
payable to you, other than the Termination Benefits, shall terminate on the date
of termination of your employment.

 

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9. Representation Regarding Other Obligations. This offer is conditioned on your
representation that your employment by and rendering of services to Repligen
Corporation as its Chief Financial Officer shall not constitute a violation of
any noncompete agreement between you and any other organization, including
Maquet Cardiovascular LLC. If you have entered into any agreement that may
restrict your activities on behalf of the Company, please provide the CEO with a
copy of such agreement as soon as possible. You also represent that you have not
violated, and covenant that you will not violate, any other obligation to any
previous employer or any other party, including that you have not used and will
not use or disclose any trade secret or other proprietary right of any previous
employer or any other party.

10. Definitions. For purposes of this Agreement:

“Cause” means (i) conduct constituting a material act of misconduct in
connection with the performance of your duties, including, without limitation,
misappropriation of funds or property of the Company or any of its subsidiaries
or affiliates other than the occasional, customary and de minimis use of Company
property for personal purposes; (ii) the commission of any felony or a
misdemeanor involving moral turpitude, deceit, dishonesty or fraud;
(iii) non-performance of your duties hereunder (other than by reason of your
physical or mental illness, incapacity or disability) or repeated violations of
your material responsibilities and material duties as determined in good faith
by the Company and which has continued for more than 30 days following written
notice which notice shall specify in reasonable detail the performance problems
and the actions required to cure such performance problems; (iv) a breach by you
of any of the material provisions contained in any other written agreement by
and between you and the Company that, if cureable, is not cured within thirty
(30) days after the Company notifies you in writing that it believes you have
materially breached your obligations under this Agreement, which notice shall
specify in reasonable detail such breach and the actions required to cure such
breach; (v) a material violation of any of the Company’s written employment
policies as applied to other employees in the Company which has continued for
more than 30 days following written notice which notice shall specify in
reasonable detail such violation and the actions required to cure such
violation; or (vi) failure to cooperate with a bona fide internal investigation
or an investigation by regulatory or law enforcement authorities, after being
instructed by the Company to cooperate, or the willful destruction or failure to
preserve documents or other materials known to be relevant to such investigation
or the inducement of others to fail to cooperate or to produce documents or
other materials in connection with such investigation.

11. Taxes; Section 409A. All forms of compensation referred to in this Agreement
are subject to reduction to reflect applicable withholding and payroll taxes and
other deductions required by law. You hereby acknowledge that the Company does
not have a duty to design its compensation policies in a manner that minimizes
your tax liabilities, and you will not make any claim against the Company or its
board of directors related to tax liabilities arising from your compensation.
Anything in this Agreement to the contrary notwithstanding, if at the time of
your separation from service within the meaning of Section 409A of the Code, the
Company determines that you are a “specified employee” within the meaning of
Section 409A(a)(2)(B)(i) of the Code, then to the extent any payment or benefit
that you become entitled to under this Agreement on account of your separation
from service would be considered deferred compensation subject to the 20 percent
additional tax imposed pursuant to Section 409A(a) of the Code as a result of
the application of Section 409A(a)(2)(B)(i) of the Code, such payment shall not
be payable and such benefit shall not be provided until the date that is the
earlier of (A) six months and one day after your separation from service, or
(B) your death. If any such delayed cash payment is otherwise payable on an
installment basis, the first payment shall include a catch-up payment covering
amounts that would otherwise have been paid during the six-month period but for
the application of this provision, and the balance of the installments shall be
payable in accordance with their original schedule. All in-kind benefits
provided and expenses eligible for reimbursement under this Agreement shall be
provided by the Company or incurred by you during the time periods set forth in
this Agreement. All reimbursements shall be paid as soon as administratively
practicable, but in no event shall any reimbursement be paid after the last day
of the taxable year following the taxable year in which the expense was
incurred. The amount of in-kind benefits provided or reimbursable expenses
incurred in one taxable year shall not affect the in-kind benefits to be
provided or the expenses eligible for reimbursement in any other taxable year.
Such right to reimbursement or in-kind benefits is not subject to liquidation or
exchange for another benefit. To the extent that any payment or benefit
described in this Agreement constitutes “non-qualified deferred compensation”
under Section 409A of the Code, and to the extent that such payment or benefit
is payable upon your termination of employment, then such payments or benefits
shall be payable only upon your “separation from service.” The determination of
whether and when a separation from service has occurred shall be made in
accordance with the presumptions set forth in Treasury Regulation
Section 1.409A-l(h). The Company and you intend that this

 

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Agreement will be administered in accordance with Section 409A of the Code. To
the extent that any provision of this Agreement is ambiguous as to its
compliance with Section 409A of the Code, the provision shall be read in such a
manner so that all payments hereunder comply with Section 409A of the Code. The
Company makes no representation or warranty and shall have no liability to you
or any other person if any provisions of this Agreement are determined to
constitute deferred compensation subject to Section 409A of the Code but do not
satisfy an exemption from, or the conditions of, such Section.

12. Interpretation, Amendment and Enforcement. This Agreement and the Equity
Documents, as modified herein, constitute the complete agreement between you and
the Company, contain all of the terms of your employment with the Company and
supersede any prior agreements, representations or understandings (whether
written, oral or implied) between you and the Company. The terms of this
Agreement and the resolution of any disputes as to the meaning, effect,
performance or validity of this Agreement or arising out of, related to, or in
any way connected with, this Agreement, your employment with the Company or any
other relationship between you and the Company (the “Disputes”) will be governed
by Massachusetts law, excluding laws relating to conflicts or choice of law. You
and the Company submit to the exclusive personal jurisdiction of the federal and
state courts located in the Commonwealth of Massachusetts in connection with any
Dispute or any claim related to any Dispute.

13. Successors and Assigns. This Agreement shall be binding upon and inure to
the benefit of both parties and their respective successors and assigns,
including any corporation with which or into which the Company may be merged or
which may succeed to its assets or business.

14. Other Terms. Your employment with the Company will be on an “at will” basis.
In other words, you or the Company may terminate your employment for any reason
and at any time, with or without cause. Although your job duties, title,
compensation and benefits, as well as the Company’s benefit plans and personnel
policies and procedures, may change from time to time, the “at will” nature of
your employment may only be changed in an express written agreement signed by
you and the Company.

In addition, this offer is subject to satisfactory background and reference
checks. As with all employees, our offer to you is also contingent on your
submission of satisfactory proof of your identity and your legal authorization
to work in the United States. You also will be required to sign, as a condition
of your employment, the Company’s standard form of restrictive covenant
agreement.

We are excited about the prospect of having you join the Company. We look
forward to receiving a response from you within one week acknowledging, by
signing below, that you have accepted this Agreement.

 

Very truly yours, By:  

/s/ Walter C. Herlihy

Name:   Walter C. Herlihy Title:   President and Chief Executive Officer

I have read and accept this employment offer:

 

By:  

/s/ Jon Snodgres

Name:   Jon Snodgres Dated:   June 10, 2014

 

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