Exhibit 10.40

JUNO THERAPEUTICS, INC.

CHANGE IN CONTROL AND SEVERANCE PLAN

AND SUMMARY PLAN DESCRIPTION

Effective as of November 4, 2015

1. Introduction. The purpose of this Juno Therapeutics, Inc. Change in Control
and Severance Plan (the “Plan”) is to provide assurances of specified benefits
to employees of the Company with a rank of “vice president” or above whose
employment is subject to being involuntarily terminated other than for death,
Disability, or Cause or voluntarily terminated for Good Reason under the
circumstances described in the Plan. This Plan is an “employee benefit plan,” as
defined in Section 3(3) of ERISA. This Plan is governed by ERISA and, to the
extent applicable, the laws of the State of Washington. This document
constitutes both the written instrument under which the Plan is maintained and
the required summary plan description for the Plan.

2. Important Terms. The following words and phrases, when the initial letter of
the term is capitalized, will have the meanings set forth in this Section 2,
unless a different meaning is plainly required by the context:

2.1. “Administrator” means the Company, acting through the Compensation
Committee or another duly constituted committee of members of the Board, or any
person to whom the Administrator has delegated any authority or responsibility
with respect to the Plan pursuant to Section 12, but only to the extent of such
delegation.

2.2. “Base Pay” means an Eligible Employee’s annualized base salary in effect
immediately prior to the termination of employment (or if the termination is due
to Good Reason based on a material reduction in base pay under Section 2.18(a),
then the Eligible Employee’s annualized base salary in effect immediately prior
to such reduction).

2.3. “Board” means the Board of Directors of the Company.

2.4. “Cause” means, with respect to an Eligible Employee, the occurrence of any
of the following: (a) an act of dishonesty made by the Eligible Employee in
connection with the Eligible Employee’s responsibilities as an employee, (b) the
Eligible Employee’s conviction of, or plea of nolo contendere to, a felony or
any crime involving fraud, embezzlement or any other act of moral turpitude, or
a material violation of federal or state law by Eligible Employee that the Board
reasonably determines has had or will have a material detrimental effect on the
Company’s reputation or business; (c) the Eligible Employee’s gross misconduct
(as defined under the Revised Code of Washington 50.04.294(4)); (d) the Eligible
Employee’s willful and material unauthorized use or disclosure of any
proprietary information or trade secrets of the Company or any other party to
whom the Eligible Employee owes an obligation of nondisclosure as a result of
the Eligible Employee’s relationship with the Company; (v) the Eligible
Employee’s willful breach of any material obligations under any written
agreement or covenant with the Company; or (vi) the Eligible Employee’s
continued substantial failure to perform the Eligible Employee’s employment
duties (other than as a result of the Eligible Employee’s physical or mental
incapacity) after the Eligible Employee has received a written demand of
performance from the Board (or in the case of Eligible Employees other than the
Section 16

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Officers and the CEO, from the CEO) that specifically sets forth the factual
basis for the Board’s (or in the case of Eligible Employees other than the
Section 16 Officers and the CEO, the CEO’s) determination that the Eligible
Employee has not substantially performed the Eligible Employee’s duties and has
failed to cure such non-performance to the Board’s (or in the case of Eligible
Employees other than the Section 16 Officers and the CEO, the CEO’s) reasonable
satisfaction within thirty (30) business days after receiving such notice. For
purposes of this Section 2.4, no act or failure to act shall be considered
willful unless it is done in bad faith and without reasonable intent that the
act or failure to act was in the best interest of the Company or required by
law. Any act, or failure to act, based upon authority or instructions given to
the Eligible Employee pursuant to a resolution duly adopted by the Board (or in
the case of Eligible Employees other than the Section 16 Officers and the CEO, a
direct instruction from the CEO) or based on the advice of counsel for the
Company will be conclusively presumed to be done or omitted to be done by the
Eligible Employee in good faith and in the best interest of the Company.

2.5. “CEO” means the Company’s Chief Executive Officer.

2.6. “Change in Control” means the occurrence of any of the following:

2.6.1. the acquisition by any one person, or more than one person acting as a
group (for these purposes, persons will be considered to be acting as a group if
they are owners of a corporation that enters into a merger, consolidation,
purchase or acquisition of stock, or similar business transaction with the
Company) (“Person”), that or is or becomes the owner, directly or indirectly, of
securities of the Company representing more than fifty percent (50%) of the
total voting power represented by the Company’s then outstanding securities;
provided, however, that for purposes of this Section 2.6.1, the acquisition of
additional securities by any one Person, who is considered to own more than
fifty percent (50%) of the total voting power of the securities of the Company
shall not be considered a Change in Control;

2.6.2. a change in the effective control of the Company which occurs on the date
that a majority of members of the Board is replaced during any twelve (12) month
period by directors whose appointment or election is not endorsed by a majority
of the members of the Board prior to the date of the appointment or election.
For purposes of this Section 2.6.2, if any Person is considered to be in
effective control of the Company, the acquisition of additional control of the
Company by the same Person will not be considered a Change in Control; or

2.6.3. a change in the ownership of a substantial portion of the Company’s
assets which occurs on the date that any Person acquires (or has acquired during
the twelve (12)-month period ending on the date of the most recent acquisition
by such person or persons) assets from the Company that have a total gross fair
market value equal to or more than fifty percent (50%) of the total fair market
value of all of the assets of the Company immediately prior to such acquisition
or acquisitions; provided, however, that for purposes of this Section 2.6.3, the
following shall not constitute a change in the ownership of a substantial
portion of the Company’s assets: (a) a transfer to an entity that is controlled
by the Company’s stockholders immediately after the transfer; or (b) a transfer
of assets by the Company to: (i) a stockholder of the Company (immediately
before the asset transfer) in exchange for or with respect to the Company’s
securities; (ii) an entity, fifty percent (50%) or more of the total value or
voting power of which is owned, directly or indirectly, by the Company; (iii) a
Person, that owns, directly or indirectly, fifty percent (50%) or more of the
total value or voting power of all the

 

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outstanding stock of the Company; or (iv) an entity, at least fifty percent
(50%) of the total value or voting power of which is owned, directly or
indirectly, by a Person described in subsection (iii). For purposes of this
Section 2.6.3, gross fair market value means the value of the assets of the
Company, or the value of the assets being disposed of, determined without regard
to any liabilities associated with such assets.

Notwithstanding the foregoing, a Company transaction that does not constitute a
change in control event under Treasury Regulation Section 1.409A-3(i)(5)(v) or
Treasury Regulation Section 1.409A-3(i)(5)(vii) shall be not be considered a
Change in Control for purposes of this Plan.

For the avoidance of doubt, a liquidation, dissolution or winding up of the
Company, or assignment for the benefit of creditors shall not constitute a
Change in Control event for purposes of this Plan.

2.7. “Change in Control Period” means the time period beginning on the date of a
Change in Control and ending on the date that is twelve (12) months following
the Change in Control.

2.8. “Code” means the Internal Revenue Code of 1986, as amended.

2.9. “Company” means Juno Therapeutics, Inc., a Delaware corporation, and any
successor that assumes the obligations of the Company under the Plan, by way of
merger, acquisition, consolidation or other transaction.

2.10. “Compensation Committee” means the Compensation Committee of the Board.

2.11. “Confidential Information” means information (including combinations of
individual items of information) that Company has or will develop, acquire,
create, compile, discover, or own, that has value in or to Company’s business
that is not generally known and that Company wishes to maintain as confidential.
“Confidential Information” includes both information disclosed by Company to
Eligible Employee and information developed or learned by Eligible Employee
during the course of employment with Company. “Confidential Information” also
includes all information of which the unauthorized disclosure could be
detrimental to the interests of Company, whether or not the information is
identified as Confidential Information. “Confidential Information” includes
non-public information that relates to the actual or anticipated business or
products, research, or development of Company, or to Company’s technical data,
trade secrets, or know-how, including research, product plans, or other
information regarding Company’s products, services, markets, customer lists, and
customers (including customers of Company on which Eligible Employee called or
with which Eligible Employee may become acquainted during the term of Eligible
Employee’s employment), software, developments, inventions, discoveries, ideas,
processes, formulas, technology, designs, drawings, engineering, hardware
configuration information, marketing, finances, and other business information
disclosed by Company either directly or indirectly in writing, orally or by
drawings or inspection of premises, parts, equipment, or other Company property.
“Confidential Information” does not include any information that (a) was
publicly known or made generally available prior to the time of disclosure by
Company to me; (b) becomes publicly known or made generally available after
disclosure by Company to me through no wrongful action or omission by Eligible
Employee; or (c) is in Eligible Employee’s rightful possession, without
confidentiality obligations, at the time of disclosure by Company as shown by
Eligible Employee’s then-contemporaneous written records,

 

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except that any combination of individual items of information shall not be
deemed to be within any of those exceptions merely because one or more of the
individual items are within that exception, unless the combination as a whole is
within that exception.

2.12. “Eligible Employee” means an employee of the Company or of any parent or
subsidiary of the Company who (a) has the rank of “vice president” (which
includes persons who do not have a “vice president” title but have a job rank at
the “vice president” level, which as of the effective date of this Plan,
includes only persons with the title of “senior medical director”) or higher and
(b) has timely and properly executed and delivered a Participation Agreement to
the Company.

2.13. “Disability” total and permanent disability as defined in Section 22(e)(3)
of the Code unless the Company maintains a long-term disability plan at the time
of the Eligible Employee’s termination, in which case the determination of
disability under such plan also will be considered “Disability” for purposes of
this Plan.

2.14. “Effective Date” means November 4, 2015.

2.15. “Equity Award” means an outstanding award granted to an Eligible Employee
by the Company pursuant to an equity plan, including but not limited to the
Company’s 2013 Equity Incentive Plan, as amended, or 2014 Equity Incentive Plan,
as amended, to purchase or receive Shares, provided that no award subject to
performance or milestone-based vesting conditions will constitute an Equity
Award.

2.16. “ERISA” means the Employee Retirement Income Security Act of 1974, as
amended.

2.17. “Territory” means (a) all counties in the State of Washington, (b) all
other states of the United States of America; and (b) all other countries of the
world; provided that, with respect to clauses (a) and (b), the Company maintains
operations, facilities, or customers in such geographic area prior to the date
of the termination of the Eligible Employee’s relationship with the Company.

2.18. “Good Reason” means, the Eligible Employee’s resignation within three
(3) months following the end of the Cure Period (as defined below), without the
Eligible Employee’s express written consent, of one or more of the following:
(a) a material reduction by the Company in the Eligible Employee’s Base Pay;
(b) a material diminution of the Eligible Employee’s authority, duties, or
responsibilities relative to the Eligible Employee’s authority, duties, or
responsibilities in effect immediately prior to such reduction; (c) a change in
the location of the Eligible Employee’s employment of more than fifty
(50) miles; or (d) the Company’s material breach of the terms of any material
written agreement or covenant with the Eligible Employee related to the Eligible
Employee’s provision of services to the Company. In order for an event to
qualify as Good Reason, the Eligible Employee must not terminate employment with
the Company without first providing the Company with written notice of the acts
or omissions constituting the grounds for “Good Reason” within three (3) months
of the initial existence of the grounds for “Good Reason” and a reasonable cure
period of thirty (30) days following the date of written notice (the “Cure
Period”), and such grounds must not have been cured during such time.

2.19. “Involuntary Termination” means a termination of employment of an Eligible
Employee under the circumstances described in Section 5.

 

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2.20. “Participation Agreement” means the individual agreement (a form of which
is shown in Appendix A) provided by the Administrator to an employee of the
Company with the title of “vice president” (which includes persons who do not
have a “vice president” title but have a job rank at the “vice president” level,
which as of the effective date of this Plan, includes only persons with the
title of “senior medical director”) or higher designating such employee as an
Eligible Employee under the Plan, which has been signed and accepted by the
employee.

2.21. “Plan” means the Juno Therapeutics, Inc. Change in Control and Severance
Plan, as set forth in this document, and as hereafter amended from time to time.

2.22. “Section 16 Officer” means the Company’s officers as determined under
Section 16 of the Securities and Exchange Act of 1934, as amended.

2.23. “Section 409A Limit” means two (2) times the lesser of: (i) the Eligible
Employee’s annualized compensation based upon the annual rate of pay paid to the
Eligible Employee during the Eligible Employee’s taxable year preceding the
Eligible Employee’s taxable year of the Eligible Employee’s termination of
employment as determined under, and with such adjustments as are set forth in,
Treasury Regulation 1.409A-1(b)(9)(iii)(A)(1) and any Internal Revenue Service
guidance issued with respect thereto; or (ii) the maximum amount that may be
taken into account under a qualified plan pursuant to Section 401(a)(17) of the
Code for the year in which the Eligible Employee’s employment is terminated.

2.24. “Severance Benefits” means the compensation and other benefits that the
Eligible Employee will be provided in the circumstances described in Section 5.

2.25. “Severance Term” means the period of time during which Eligible Employee
is receiving Severance Benefits, with the maximum extent of such period as set
forth in Section 5.1.3 and Section 5.2.3, respectively.

2.26. “Share” means a share of the Company’s common stock.

2.27. “Target Bonus” means either (i) the Eligible Employee’s target bonus
percentage multiplied by the Eligible Employee’s Base Pay or (ii) the target
bonus amount (as applicable), in each case, as in effect for the Company’s (or
its successor’s) fiscal year in which the Eligible Employee’s Involuntary
Termination occurs.

2.28. “Tier” means the tier of Severance Benefits an Eligible Employee is
entitled to receive under the Plan pursuant to Section 5, depending on the rank
of the Eligible Employee on the date the right to Severance Benefits is
triggered, as set forth below:

2.28.1. “Tier 1” applies to the CEO.

2.28.2. “Tier 2” applies to any Section 16 Officer other than the CEO.

2.28.3. “Tier 3” applies to any Eligible Employee who is not the CEO or a
Section 16 Officer.

3. Change in Control Benefits. An individual who is an Eligible Employee on the
date that the Company experiences a Change in Control will be entitled to
receive the following benefits:

 

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3.1. With respect to any Equity Award held by an Eligible Employee that was
granted after November 4, 2015, 25% of the unvested Shares subject to the Equity
Award will become vested and exercisable, if applicable, immediately prior to
the Change in Control.

3.2. In the event that the successor corporation does not assume, or provide a
substantially economically equivalent substitute award with the same vesting
schedule or vesting provisions that are more favorable to the Eligible Employee,
for an Equity Award held by an Eligible Employee, such Equity Award will become
fully vested and exercisable, if applicable, immediately prior to the Change in
Control, in accordance with the terms and conditions of the Plan.

4. Eligibility for Severance Benefits. An individual is eligible for Severance
Benefits under the Plan, as described in Section 5, only if he or she is an
Eligible Employee on the date he or she experiences an Involuntary Termination.

5. Involuntary Termination.

5.1. Termination During the Change in Control Period. If, during the Change in
Control Period, (i) an Eligible Employee terminates his or her employment with
the Company (or any parent or subsidiary of the Company) for Good Reason, or
(ii) the Company (or any parent or subsidiary of the Company) terminates the
Eligible Employee’s employment for a reason other than Cause and other than the
Eligible Employee’s death or Disability, then, subject to the Eligible
Employee’s compliance with Section 7, the Eligible Employee will receive the
following Severance Benefits from the Company:

5.1.1. Salary Severance Benefits. A lump-sum payment of cash salary severance,
payable within the period of time set forth in the Eligible Employee’s
Participation Agreement, equal to the number of months of annualized Bay Pay as
set forth below:

(a) Tier 1: 24 months

(b) Tier 2: 12 months

(c) Tier 3: 9 months

5.1.2. Bonus Severance Benefits. A lump-sum payment of cash bonus severance
equal to the greater of (i) 100% of the Eligible Employee’s Target Bonus,
pro-rated based on the proportion of the then-current fiscal year the Eligible
Employee served through the date of the Eligible Employee’s Involuntary
Termination, or (ii) the Eligible Employee’s actual achievement against target
objectives as applied to the Eligible Employee’s Target Bonus as of the date of
the Eligible Employee’s Involuntary Termination.

5.1.3. Continued Medical Benefits. If the Eligible Employee, and any spouse
and/or dependents of the Eligible Employee (“Family Members”) has coverage on
the date of the Eligible Employee’s Involuntary Termination under a group health
plan sponsored by the Company, the Company will reimburse the Eligible Employee
the total applicable premium cost for continued group health plan coverage under
the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended (“COBRA”)
during the period of time following the Eligible Employee’s employment
termination, as set forth below, provided that the Eligible Employee validly
elects and is eligible to continue coverage

 

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under COBRA for the Eligible Employee and his Family Members. However, if the
Company determines in its sole discretion that it cannot provide the COBRA
reimbursement benefits without potentially violating applicable laws (including,
without limitation, Section 2716 of the Public Health Service Act and the
Employee Retirement Income Security Act of 1974, as amended), the Company will
in lieu thereof provide to the Eligible Employee a taxable monthly payment in an
amount equal to the monthly COBRA premium that the Eligible Employee would be
required to pay to continue the group health coverage in effect on the date of
the Eligible Employee’s termination of employment (which amount will be based on
the premium for the first month of COBRA coverage) for the period of time set
forth below, which payments will be made regardless of whether the Eligible
Employee elects COBRA continuation coverage:

(a) Tier 1: 24 months

(b) Tier 2: 12 months

(c) Tier 3: 9 months

5.1.4. Equity Award Vesting Acceleration. Accelerated vesting as to 100% of the
unvested Shares subject to the Eligible Employee’s then-outstanding Equity
Awards, provided that such Equity Awards were granted on or after November 4,
2015.

5.2. Termination Other Than During the Change in Control Period. If the Company
(or any parent or subsidiary of the Company) terminates the Eligible Employee’s
employment for a reason other than Cause and other than the Eligible Employee’s
death or Disability and such termination occurs other than during the Change in
Control Period, then, subject to the Eligible Employee’s compliance with
Section 7, the Eligible Employee will receive the following Severance Benefits
from the Company:

5.2.1. Cash Severance Benefits. Continuing payments of Base Pay as cash
severance, payable in accordance with the Company’s payroll practice as in
effect from time to time, for the number of months following the Eligible
Employee’s termination of employment as set forth below:

(a) Tier 1: 12 months

(b) Tier 2: 12 months

(c) Tier 3: 9 months

5.2.2. Bonus Severance Benefits. A lump-sum payment of cash bonus severance
equal to the greater of (i) 100% of the Eligible Employee’s Target Bonus,
pro-rated based on the proportion of the then-current fiscal year the Eligible
Employee served through the date of the Eligible Employee’s Involuntary
Termination, or (ii) the Eligible Employee’s actual achievement against target
objectives as applied to the Eligible Employee’s Target Bonus as of the date of
the Eligible Employee’s Involuntary Termination.

5.2.3. Continued Medical Benefits. If the Eligible Employee, and any Family
Members, has coverage on the date of the Eligible Employee’s Involuntary
Termination under a group health plan sponsored by the Company, the Company will
reimburse the Eligible Employee the total applicable

 

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premium cost for continued group health plan coverage under COBRA during the
period of time following the Eligible Employee’s employment termination, as set
forth below, provided that the Eligible Employee validly elects and is eligible
to continue coverage under COBRA for the Eligible Employee and his Family
Members. However, if the Company determines in its sole discretion that it
cannot provide the COBRA reimbursement benefits without potentially violating
applicable laws (including, without limitation, Section 2716 of the Public
Health Service Act and the Employee Retirement Income Security Act of 1974, as
amended), the Company will in lieu thereof provide to the Eligible Employee a
taxable monthly payment in an amount equal to the monthly COBRA premium that the
Eligible Employee would be required to pay to continue the group health coverage
in effect on the date of the Eligible Employee’s termination of employment
(which amount will be based on the premium for the first month of COBRA
coverage) for the period of time set forth below, which payments will be made
regardless of whether the Eligible Employee elects COBRA continuation coverage:

(a) Tier 1: 12 months

(b) Tier 2: 12 months

(c) Tier 3: 9 months

6. Limitation on Payments. In the event that the payments and benefits provided
for in the Plan or other payments and benefits payable or provided to the
Eligible Employee (i) constitute “parachute payments” within the meaning of
Section 280G of the Code and (ii) but for this Section 6, would be subject to
the excise tax imposed by Section 4999 of the Code, then the Eligible Employee’s
payments and benefits under the Plan or other payments or benefits (the “280G
Amounts”) will be either:

(a) delivered in full; or

(b) delivered as to such lesser extent that would result in no portion of the
280G Amounts being subject to the excise tax under Section 4999 of the Code;

whichever of the foregoing amounts, taking into account the applicable federal,
state and local income taxes and the excise tax imposed by Section 4999, results
in the receipt by the Eligible Employee on an after-tax basis, of the greatest
amount of 280G Amounts, notwithstanding that all or some portion of the
280G Amounts may be taxable under Section 4999 of the Code.

6.1. Reduction Order. In the event that a reduction of 280G Amounts is made in
accordance with Section 6, the reduction will occur, with respect to the
280G Amounts considered parachute payments within the meaning of Section 280G of
the Code, in the following order:

(a) reduction of cash payments in reverse chronological order (that is, the cash
payment owed on the latest date following the occurrence of the event triggering
the excise tax will be the first cash payment to be reduced);

(b) cancellation of equity awards that were granted “contingent on a change in
ownership or control” within the meaning of Code Section 280G;

 

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(c) reduction of the accelerated vesting of equity awards in the reverse order
of date of grant of the awards (i.e., the vesting of the most recently granted
equity awards will be cancelled first); and

(d) reduction of employee benefits in reverse chronological order (i.e., the
benefit owed on the latest date following the occurrence of the event triggering
the excise tax will be the first benefit to be reduced).

In no event will the Eligible Employee have any discretion with respect to the
ordering of payment reductions.

6.2. Nationally Recognized Firm Requirement. Unless the Company and the Eligible
Employee otherwise agree in writing, any determination required under this
Section 6 will be made in writing by a nationally recognized accounting or
valuation firm (the “Firm”) selected by the Administrator, whose determination
will be conclusive and binding upon the Eligible Employee and the Company for
all purposes. For purposes of making the calculations required by this
Section 6, the Firm may make reasonable assumptions and approximations
concerning applicable taxes and may rely on reasonable, good faith
interpretations concerning the application of Sections 280G and 4999 of the
Code. The Company and the Eligible Employee will furnish to the Firm such
information and documents as the Firm may reasonably request in order to make a
determination under this Section 6. The Company will bear all costs for payment
of the Firm’s services in connection with any calculations contemplated by this
Section 6.

7. Conditions to Receipt of Severance. Eligible Employee is required to comply
with all the conditions set forth in this Section 7 to receive Severance
Benefits under the Plan.

7.1. Release Agreement. As a condition to receiving the Severance Benefits under
this Plan, each Eligible Employee will be required to sign and not revoke a
separation and release of claims agreement in a form reasonably satisfactory to
the Company (the “Release”). In all cases, the Release must become effective and
irrevocable no later than the sixtieth (60th) day following the Eligible
Employee’s Involuntary Termination (the “Release Deadline Date”). If the Release
does not become effective and irrevocable by the Release Deadline Date, the
Eligible Employee will forfeit any right to the Severance Benefits. In no event
will the Severance Benefits be paid or provided until the Release becomes
effective and irrevocable.

7.2. Non-Competition and Non-Solicitation.

7.2.1 As a condition of receiving the Severance Benefits under the Plan, and in
order to protect Confidential Information, each Eligible Employee will not,
either directly or indirectly, during the Severance Term:

(a)(i) serve as an advisor, agent, consultant, director, employee, officer,
partner, proprietor or otherwise of, (ii) have any ownership interest in (except
for passive ownership of one percent (1%) or less of any entity whose securities
have been registered under the Securities Act of 1933, as amended, or Section 12
of the Securities Exchange Act of 1934, as amended), or (iii) participate in the
organization, financing, operation, management or control of, any business in
competition with the Company’s business as conducted by the Company at any time
during the course of Eligible Employee’s employment with the Company. This
covenant shall cover Eligible Employee’s activities

 

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in every part of the Territory, as defined herein, to the extent permitted by
applicable law. Eligible Employee acknowledges and agrees that fulfillment of
the obligations contained in this covenant, including, but not limited to,
Eligible Employee’s obligation neither to use, except for the benefit of the
Company, or to disclose the Company’s Confidential Information and Eligible
Employee’s obligation not to compete is necessary to protect the Company’s
Confidential Information and to preserve the Company’s value and goodwill.
Eligible Employee further acknowledges the time, geographic, and scope
limitations of Eligible Employee’s obligations under this Section 7.2 are
reasonable, especially in light of the Company’s desire to protect its
Confidential Information, and that Eligible Employee will not be precluded from
gainful employment if Eligible Employee is obligated not to compete with the
Company during the period and within the Territory as described above.

(b) solicit sales from any of Company’s customers for any product or service
that (i) competes with any product or service sold or provided by Company,
(ii) competes with any product or service intended to be sold or provided by
Company at the time of the termination of Eligible Employee’s employment with
Company, or (iii) competed with any product or service sold or provided by
Company at any time during Eligible Employee’s employment with Company;

(c) entice any vendor, consultant, collaborator, agent, or contractor of Company
to cease its business relationship with Company or engage in any activity that
would cause them to cease their business relationship with Company; or

(d) solicit, induce, recruit, or encourage any of Company’s employees to leave
their employment, or attempt to solicit, induce, recruit, encourage, or take
away Company employees.

7.2.2 Severability. The covenants contained in Section 7.2 shall be construed as
a series of separate covenants, one for each city, county and state of any
geographic area in the Territory. Except for geographic coverage, each such
separate covenant shall be deemed identical in terms to the covenant contained
in subsection 7.2.1 above. If, in any judicial or arbitration proceeding, a
court or arbitrator refuses to enforce any of such separate covenants (or any
part thereof), then such unenforceable covenant (or such part) shall be
eliminated from this Agreement to the extent necessary to permit the remaining
separate covenants (or portions thereof) to be enforced. In the event the
provisions of subsection 7.2.1 above are deemed to exceed the time, geographic,
or scope limitations permitted by applicable law, then such provisions shall be
reformed by the court or arbitrator to cover the maximum time, geographic, or
scope limitations, as the case may be, then permitted by such law.

7.2.3 Reasonableness. The nature of Company’s business is such that if Eligible
Employee were to become employed by, or substantially involved in, the business
of a competitor to Company, it would be difficult not to rely on or use
Confidential Information. Therefore, Eligible Employee enters into this
Agreement to reduce the likelihood of disclosure of Confidential Information, as
well as to protect the value and goodwill of the Company. Eligible Employee
acknowledge that the limitations of time, geography, and scope of activity
agreed to above are reasonable because, among other things, (a) Company is
engaged in a highly competitive industry, (b) Eligible Employee will have access
to Confidential Information, including but not limited to, Company’s trade
secrets, know-how, plans, and strategy (and in particular, the competitive
strategy of Company), (c) in the event Eligible Employee’s employment with
Company ends, Eligible Employee will be able to obtain suitable and satisfactory
employment in Eligible Employee’s chosen profession without violating this
Agreement, and (d) these limitations are necessary to protect Confidential
Information and the goodwill of Company.

 

10

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7.3. Non-Disparagement. During the Severance Term, Eligible Employee agrees to
refrain from any disparagement, defamation, libel, or slander of the Company,
and agrees to refrain from any tortious interference with the contracts and
relationships of the Company. For the avoidance of doubt, reports to, or
responses to inquiries by, auditors, the Company’s Board of Directors, the audit
committee, or any government agency, as long as such reports or responses are
truthful, shall not constitute disparagement.

7.4. Other Requirements. An Eligible Employee’s receipt of Severance Benefits
will be subject to the Eligible Employee continuing to comply with the
provisions of this Section 7 and the terms of any confidentiality, proprietary
information and inventions agreement (however titled, but such agreements used
by the Company in the United States as the Effective Date are titled “At-Will
Employee Agreement”), including any non-competition and non-solicitation
covenants contained therein (which are additional obligations, and not replaced
by the provisions of this Section 7), and such other appropriate agreements
between the Eligible Employee and the Company. Severance Benefits under this
Plan will terminate immediately for an Eligible Employee if the Eligible
Employee, at any time, violates any such agreement and/or the provisions of this
Section 7.

8. Timing of Severance Benefits. Provided that the Release becomes effective and
irrevocable by the Release Deadline Date and subject to Section 10, the
severance payments and benefits under this Plan will be paid, or in the case of
installments, will commence, on the Release Deadline Date (such payment date,
the “Severance Start Date”), and any severance payments or benefits otherwise
payable to the Eligible Employee during the period immediately following the
Eligible Employee’s termination of employment with the Company through the
Severance Start Date will be paid in a lump sum to the Eligible Employee on the
Severance Start Date, with any remaining payments to be made as provided in this
Plan.

9. Non-Duplication of Benefits; Survival of Other Benefits. Notwithstanding any
other provision in the Plan to the contrary, if the Eligible Employee is
entitled to any severance, change in control or similar benefits outside of the
Plan by operation of applicable law or under another Company-sponsored plan,
policy, contract, or arrangement, his or her benefits under the Plan will be
reduced by the value of the severance, change in control or similar benefits
that the Eligible Employee receives by operation of applicable law or under any
Company-sponsored plan, policy, contract, or arrangement, all as determined by
the Administrator in its discretion. Subject to the foregoing, this Plan is not
intended to amend, modify, terminate, or supersede any severance, change in
control or similar benefits provided under any contract with any Eligible
Employee, and to the extent any such contract offers severance, change in
control or similar benefits that are more advantageous to the Eligible Employee
than the terms hereof, such Eligible Employee shall continue to be entitled to
such benefits.

10. Section 409A.

10.1. Notwithstanding anything to the contrary in this Plan, no severance
payments or benefits to be paid or provided to an Eligible Employee, if any,
under this Plan that, when considered together with any other severance payments
or separation benefits, are considered deferred compensation under Section 409A
of the Code, and the final regulations and any guidance promulgated thereunder
(“Section 409A”) (together, the “Deferred Payments”) will be paid or provided
until the Eligible Employee has a “separation from service” within the meaning
of

 

11

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Section 409A. Similarly, no severance payable to an Eligible Employee, if any,
under this Plan that otherwise would be exempt from Section 409A pursuant to
Treasury Regulation Section 1.409A-1(b)(9) will be payable until the Eligible
Employee has a “separation from service” within the meaning of Section 409A.

10.2. It is intended that none of the severance payments or benefits under this
Plan will constitute Deferred Payments but rather will be exempt from
Section 409A as a payment that would fall within the “short-term deferral
period” as described in Section 10.4 below or resulting from an involuntary
separation from service as described in Section 10.5 below. In no event will an
Eligible Employee have discretion to determine the taxable year of payment of
any Deferred Payment.

10.3. Notwithstanding anything to the contrary in this Plan, if an Eligible
Employee is a “specified employee” within the meaning of Section 409A at the
time of the Eligible Employee’s separation from service (other than due to
death), then the Deferred Payments, if any, that are payable within the first
six (6) months following the Eligible Employee’s separation from service, will
become payable on the date six (6) months and one (1) day following the date of
the Eligible Employee’s separation from service. All subsequent Deferred
Payments, if any, will be payable in accordance with the payment schedule
applicable to each payment or benefit. Notwithstanding anything herein to the
contrary, in the event of the Eligible Employee’s death following the Eligible
Employee’s separation from service, but before the six (6) month anniversary of
the separation from service, then any payments delayed in accordance with this
paragraph will be payable in a lump sum as soon as administratively practicable
after the date of the Eligible Employee’s death and all other Deferred Payments
will be payable in accordance with the payment schedule applicable to each
payment or benefit. Each payment and benefit payable under this Plan is intended
to constitute a separate payment under Section 1.409A-2(b)(2) of the Treasury
Regulations.

10.4. Any amount paid under this Plan that satisfies the requirements of the
“short-term deferral” rule set forth in Section 1.409A-1(b)(4) of the Treasury
Regulations will not constitute Deferred Payments for purposes of Section 10.1
above.

10.5. Any amount paid under this Plan that qualifies as a payment made as a
result of an involuntary separation from service pursuant to
Section 1.409A-1(b)(9)(iii) of the Treasury Regulations that does not exceed the
Section 409A Limit will not constitute Deferred Payments for purposes of
Section 10.1 above.

10.6. The foregoing provisions are intended to comply with or be exempt from the
requirements of Section 409A so that none of the payments and benefits to be
provided under the Plan will be subject to the additional tax imposed under
Section 409A, and any ambiguities herein will be interpreted to so comply or be
exempt. Notwithstanding anything to the contrary in the Plan, including but not
limited to Sections 12 and 14, the Company reserves the right to amend the Plan
as it deems necessary or advisable, in its sole discretion and without the
consent of the Eligible Employees, to comply with Section 409A or to avoid
income recognition under Section 409A prior to the actual payment of benefits
under the Plan or imposition of any additional tax. In no event will the Company
reimburse an Eligible Employee for any taxes that may be imposed on the Eligible
Employee as result of Section 409A.

 

12

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11. Withholdings. The Company will withhold from any payments or benefits under
the Plan all applicable U.S. federal, state, local and non-U.S. taxes required
to be withheld and any other required payroll deductions.

12. Administration. The Company is the administrator of the Plan (within the
meaning of section 3(16)(A) of ERISA). The Plan will be administered and
interpreted by the Administrator (in his or her sole discretion). The
Administrator is the “named fiduciary” of the Plan for purposes of ERISA and
will be subject to the fiduciary standards of ERISA when acting in such
capacity. Any decision made or other action taken by the Administrator with
respect to the Plan, and any interpretation by the Administrator of any term or
condition of the Plan, or any related document, will be conclusive and binding
on all persons and be given the maximum possible deference allowed by law. In
accordance with Section 2.1, the Administrator (a) may, in its sole discretion
and on such terms and conditions as it may provide, delegate in writing to one
or more officers of the Company all or any portion of its authority or
responsibility with respect to the Plan, and (b) has the authority to act for
the Company (in a non-fiduciary capacity) as to any matter pertaining to the
Plan; provided, however, that any Plan amendment or termination or any other
action that reasonably could be expected to increase materially the cost of the
Plan must be approved by the Board.

13. Eligibility to Participate. To the extent that the Administrator has
delegated administrative authority or responsibility to one or more officers of
the Company in accordance with Sections 2.1 and 12, each such officer will not
be excluded from participating in the Plan if otherwise eligible, but he or she
is not entitled to act upon or make determinations regarding any matters
pertaining specifically to his or her own benefit or eligibility under the Plan.
The Administrator will act upon and make determinations regarding any matters
pertaining specifically to the benefit or eligibility of each such officer under
the Plan.

14. Term. The Plan will become effective upon the Effective Date and will
terminate automatically upon the completion of all payments (if any) under the
terms of the Plan.

15. Amendment or Termination. The Company, by action of the Administrator,
reserves the right to amend or terminate the Plan at any time, without advance
notice to any Eligible Employee and without regard to the effect of the
amendment or termination on any Eligible Employee or on any other individual.
Any amendment or termination of the Plan will be in writing. Notwithstanding the
foregoing, the Company may not, without an Eligible Employee’s written consent,
amend or terminate the Plan in any way, nor take any other action, that
(i) prevents that Eligible Employee from becoming eligible for the Severance
Benefits under the Plan, or (ii) reduces or alters to the detriment of the
Eligible Employee the Severance Benefits payable, or potentially payable, to an
Eligible Employee under the Plan (including, without limitation, imposing
additional conditions). Any action of the Company in amending or terminating the
Plan will be taken in a non-fiduciary capacity.

16. Claims and Appeals.

16.1. Claims Procedure. Any employee or other person who believes he or she is
entitled to any payment under the Plan may submit a claim in writing to the
Administrator within ninety (90) days of the earlier of (i) the date the
claimant learned the amount of his or her benefits under the Plan or (ii) the
date the claimant learned that he or she will not be entitled to any benefits
under the Plan. If the claim is denied (in full or in part), the claimant will
be provided a written notice explaining the

 

13

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specific reasons for the denial and referring to the provisions of the Plan on
which the denial is based. The notice also will describe any additional
information needed to support the claim and the Plan’s procedures for appealing
the denial. The denial notice will be provided within ninety (90) days after the
claim is received. If special circumstances require an extension of time (up to
ninety (90) days), written notice of the extension will be given within the
initial ninety (90) day period. This notice of extension will indicate the
special circumstances requiring the extension of time and the date by which the
Administrator expects to render its decision on the claim.

16.2. Appeal Procedure. If the claimant’s claim is denied, the claimant (or his
or her authorized representative) may apply in writing to the Administrator for
a review of the decision denying the claim. Review must be requested within
sixty (60) days following the date the claimant received the written notice of
their claim denial or else the claimant loses the right to review. The claimant
(or representative) then has the right to review and obtain copies of all
documents and other information relevant to the claim, upon request and at no
charge, and to submit issues and comments in writing. The Administrator will
provide written notice of its decision on review within sixty (60) days after it
receives a review request. If additional time (up to sixty (60) days) is needed
to review the request, the claimant (or representative) will be given written
notice of the reason for the delay. This notice of extension will indicate the
special circumstances requiring the extension of time and the date by which the
Administrator expects to render its decision. If the claim is denied (in full or
in part), the claimant will be provided a written notice explaining the specific
reasons for the denial and referring to the provisions of the Plan on which the
denial is based. The notice also will include a statement that the claimant will
be provided, upon request and free of charge, reasonable access to, and copies
of, all documents and other information relevant to the claim and a statement
regarding the claimant’s right to bring an action under Section 502(a) of ERISA.

17. Attorneys’ Fees. The parties shall each bear their own expenses, legal fees
and other fees incurred in connection with this Plan. Provided, however, in the
event that an Eligible Employee is required to incur attorneys’ fees in order to
obtain any payments or benefits under this Plan, and provided that the Eligible
Employee prevails on at least one material issue related to his or her claim(s)
under the Plan, then the Company will reimburse the attorneys’ fees incurred by
the Eligible Employee. The reimbursements will be made in accordance with the
Company’s normal reimbursement policies following final adjudication of the
Eligible Employee’s claims, provided however, that (a) the reimbursements are
payable only during the Eligible Employee’s lifetime, (b) the reimbursements
will be made on or before the last day of the Eligible Employee’s taxable year
following the taxable year in which the expenses were incurred, (c) the right to
reimbursement, if any, is not subject to liquidation or exchange for another
benefit, and (d) the amount of expenses eligible for reimbursement during an
Eligible Employee’s taxable year will not affect the expenses eligible for
reimbursement to be provided in any other taxable year.

18. Source of Payments. All Severance Benefits, other than Equity Award
acceleration, will be paid in cash from the general funds of the Company; no
separate fund will be established under the Plan, and the Plan will have no
assets. No right of any person to receive any payment under the Plan will be any
greater than the right of any other general unsecured creditor of the Company.

19. Inalienability. In no event may any current or former employee of the
Company or any of its subsidiaries or affiliates sell, transfer, anticipate,
assign or otherwise dispose of any right or interest under the Plan. At no time
will any such right or interest be subject to the claims of creditors nor liable
to attachment, execution or other legal process.

 

14

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20. No Enlargement of Employment Rights. Neither the establishment or
maintenance or amendment of the Plan, nor the making of any benefit payment
hereunder, will be construed to confer upon any individual any right to continue
to be an employee of the Company. The Company expressly reserves the right to
discharge any of its employees at any time, with or without cause. However, as
described in the Plan, an Eligible Employee may be entitled to benefits under
the Plan depending upon the circumstances of his or her termination of
employment.

21. Successors. Any successor to the Company of all or substantially all of the
Company’s business and/or assets (whether direct or indirect and whether by
purchase, merger, consolidation, liquidation or other transaction) will assume
the obligations under the Plan and agree expressly to perform the obligations
under the Plan in the same manner and to the same extent as the Company would be
required to perform such obligations in the absence of a succession. For all
purposes under the Plan, the term “Company” will include any successor to the
Company’s business and/or assets which become bound by the terms of the Plan by
operation of law, or otherwise.

22. Applicable Law. The provisions of the Plan will be construed, administered
and enforced in accordance with ERISA and, to the extent applicable, the
internal substantive laws of the state of Washington (but not its conflict of
laws provisions).

23. Severability. If any provision of the Plan is held invalid or unenforceable,
its invalidity or unenforceability will not affect any other provision of the
Plan, and the Plan will be construed and enforced as if such provision had not
been included.

24. Headings. Headings in this Plan document are for purposes of reference only
and will not limit or otherwise affect the meaning hereof.

25. Indemnification. The Company hereby agrees to indemnify and hold harmless
the officers and employees of the Company, and the members of its Board, from
all losses, claims, costs or other liabilities arising from their acts or
omissions in connection with the administration, amendment or termination of the
Plan, to the maximum extent permitted by applicable law. This indemnity will
cover all such liabilities, including judgments, settlements and costs of
defense. The Company will provide this indemnity from its own funds to the
extent that insurance does not cover such liabilities. This indemnity is in
addition to and not in lieu of any other indemnity provided to such person by
the Company.

26. Additional Information.

 

Plan Name:

 

Juno Therapeutics, Inc. Change in Control and Severance Plan

 

Plan Sponsor:

  Juno Therapeutics, Inc.   c/o People Department   307 Westlake Avenue North,
Suite 300   Seattle, WA 98109

 

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Identification Numbers:

  EIN: - 46-3656275  

PLAN: 502

 

Plan Year:

  Company’s fiscal year

Plan Administrator:

  Juno Therapeutics, Inc.  
Attention: Administrator of the Juno Therapeutics, Inc.   Change in Control and
Severance Plan   307 Westlake Avenue North, Suite 300   Seattle, WA 98109  

206-582-1600

 

Agent for Service of

 

Legal Process:

  Juno Therapeutics, Inc.   Attention: General Counsel   307 Westlake Avenue
North, Suite 300   Seattle, WA 98109  

206-582-1600

 

Type of Plan

 

Severance Plan/Employee Welfare Benefit Plan

 

Plan Costs

  The cost of the Plan is paid by the Employer.

27. Statement of ERISA Rights.

As an Eligible Employee under the Plan, you have certain rights and protections
under ERISA:

(a) You may examine (without charge) all Plan documents, including any
amendments and copies of all documents filed with the U.S. Department of Labor.
These documents are available for your review in the Company’s Human Resources
Department.

(b) You may obtain copies of all Plan documents and other Plan information upon
written request to the Administrator. A reasonable charge may be made for such
copies.

In addition to creating rights for Eligible Employees, ERISA imposes duties upon
the people who are responsible for the operation of the Plan. The people who
operate the Plan (called “fiduciaries”) have a duty to do so prudently and in
the interests of you and the other Eligible Employees. No one, including the
Company or any other person, may fire you or otherwise discriminate against you
in any way to prevent you from obtaining a benefit under the Plan or exercising
your rights under ERISA. If your claim for a severance benefit is denied, in
whole or in part, you must receive a written explanation of the reason for the
denial. You have the right to have the denial of your claim reviewed. (The claim
review procedure is explained in Section 16 above.)

Under ERISA, there are steps you can take to enforce the above rights. For
example, if you request materials and do not receive them within thirty
(30) days, you may file suit in a federal court. In such a case, the court may
require the Administrator to provide the materials and to pay you up to $110 a
day until you receive the materials, unless the materials were not sent due to
reasons beyond the control of the Administrator. If you have a claim which is
denied or ignored, in whole or in part, you may file suit in a federal court. If
it should happen that you are discriminated against for asserting your rights,
you may seek assistance from the U.S. Department of Labor, or you may file suit
in a federal court.

 

16

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In any case, the court will decide who will pay court costs and legal fees. If
you are successful, the court may order the person you have sued to pay these
costs and fees. If you lose, the court may order you to pay these costs and
fees, for example, if it finds that your claim is frivolous.

If you have any questions regarding the Plan, please contact the Administrator.
If you have any questions about this statement or about your rights under ERISA,
you may contact the nearest area office of the Employee Benefits Security
Administration (formerly the Pension and Welfare Benefits Administration), U.S.
Department of Labor, listed in your telephone directory, or the Division of
Technical Assistance and Inquiries, Employee Benefits Security Administration,
U.S. Department of Labor, 200 Constitution Avenue, N.W. Washington, D.C. 20210.
You also may obtain certain publications about your rights and responsibilities
under ERISA by calling the publications hotline of the Employee Benefits
Security Administration.

o 0 o

 

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Appendix A

Juno Therapeutics, Inc. Change in Control and Severance Plan

Form of Participation Agreement

Juno Therapeutics, Inc. (the “Company”) is pleased to inform you,
                                        , that you have been selected to
participate in the Company’s Change in Control and Severance Plan (the “Plan”).
A copy of the Plan was delivered to you with this Participation Agreement. Your
participation in the Plan is subject to all of the terms and conditions of the
Plan.

In order to actually become a participant in the Plan (an “Eligible Employee” as
described in the Plan), you must complete and sign this Participation Agreement
and return it to [NAME] no later than [DATE].

The Plan describes in detail certain circumstances under which you may become
eligible for Severance Benefits. As described more fully in the Plan, you may
become eligible for certain Severance Benefits under Section 5.1 of the Plan if,
during the Change in Control Period, you voluntarily terminate your employment
with the Company (or any parent or subsidiary of the Company) for Good Reason or
the Company (or any parent or subsidiary of the Company) terminates your
employment for a reason other than Cause and other than as a result of your
Disability or death. In addition (but in lieu of the Severance Benefits
described in the preceding sentence), as described more fully in the Plan, you
may become eligible for certain Severance Benefits under Section 5.2 of the Plan
if the Company (or any parent or subsidiary of the Company) terminates your
employment for a reason other than Cause and other than as a result of your
Disability or death, and such termination occurs other than during the Change in
Control Period.

In order to receive any Severance Benefits for which you otherwise become
eligible under the Plan, you must sign and deliver to the Company the Release,
which must have become effective and irrevocable within the requisite period,
and adhere to the non-disparagement, non-competition and non-solicitation
provisions of the Plan throughout the Severance Term. Also, as explained in the
Plan, your Severance Benefits (if any) will be reduced if necessary to avoid
your Severance Benefits from becoming subject to “golden parachute” excise taxes
under the Internal Revenue Code.

By your signature below, you and the Company agree that your participation in
the Plan is governed by this Participation Agreement and the provisions of the
Plan. Your signature below confirms that: (1) you have received a copy of the
Change in Control and Severance Plan and Summary Plan Description; (2) you have
carefully read this Participation Agreement and the Change in Control and
Severance Plan and Summary Plan Description; and (3) decisions and
determinations by the Administrator under the Plan will be final and binding on
you and your successors.

[Signature Page Follows]

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JUNO THERAPEUTICS, INC.     [ELIGIBLE EMPLOYEE NAME]

 

   

 

Signature     Signature

 

   

 

Name     Date

 

    Title    

Attachment: Juno Therapeutics, Inc. Change in Control and Severance Plan

[Signature Page to the Participation Agreement]