Exhibit 10.1

SEATTLE GENETICS, INC.

SEVERANCE AND RELEASE AGREEMENT

This Severance and Release Agreement (the “Agreement”) is entered into as of
February 23, 2012 (the “Effective Date”) by and between Seattle Genetics, Inc.
(the “Company”) and Bruce J. Seeley (“Employee”).

WHEREAS, Employee has been employed as the Company’s Executive Vice President,
Commercial;

WHEREAS, the Company and Employee have mutually agreed to terminate Employee’s
employment relationship on the terms set forth below;

NOW, THEREFORE, in consideration of the mutual promises made herein, the receipt
and sufficiency of which are hereby acknowledged by the Company and Employee,
both of them hereby agree as follows:

1. Termination of Employment. The effective date of the termination of
Employee’s employment with the Company shall be March 1, 2012 (the “Termination
Date”). Employee shall, until otherwise directed by the Company, continue to
perform his regular job duties and responsibilities for the Company through the
Termination Date and shall continue to comply with all Company policies and
procedures. The Company shall pay to Employee his salary and accrued but unused
vacation through the Termination Date. In addition, the Company shall provide
all benefits due to Employee with respect to his employment through the
Termination Date.

2. Consideration. In consideration for the release of claims set forth in
Section 4 below and other obligations under this Agreement, and provided that
Employee does not revoke his execution of this Agreement during the Revocation
Period described in Section 5 below, the Company agrees to provide to Employee
the following benefits following the Termination Date:

(a) payment of a single lump sum gross severance amount, subject to withholding
of applicable taxes, which is equal to twelve (12) months of Employee’s regular
base salary;

(b) payment of a single lump sum gross severance amount, subject to withholding
of applicable taxes, which is equal to a pro-rated bonus of two (2) months using
an earned rate of one hundred percent (100%) for individual and Company
performance at the forty percent (40%) threshold for the Executive Vice
President position;

(c) continued health insurance benefits through COBRA payments from the
Termination Date through March 1, 2013 provided that Employee properly and
timely elects such coverage as provided for in the Company’s COBRA notice
materials;

(d) Employee’s options for the Company’s common stock and restricted stock units
outstanding and unvested as of the Termination Date shall accelerate in vesting
for a period equal to twelve (12) months in accordance with the terms of the
Company’s 2007 Equity Incentive Plan and Employee’s stock option agreements,
including the provision that any outstanding vested options must be exercised
within ninety (90) days of the Termination Date or such options shall be
terminated; and

(e) provision of reasonable career outplacement services as part of Career
Transition Services provided by Lee Hecht Harrison for up to six (6) months.

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3. Property Return. Prior to the Termination Date, Employee agrees to return to
the Company all Company-owned property in Employee’s possession, such as all
keys to Company buildings or property, all Company-owned equipment, including
laptops and cellular phones, all Company software, documents and papers (such as
reports, presentations, notebooks, and files), all Company credit cards, and all
other Company property. Employee agrees to destroy personal copies of such
property and shall not use or transfer any Company property to others.

4. Release of Claims. In exchange for the consideration provided under this
Agreement, Employee and his successors and assigns hereby fully and forever
release and discharge the Company, any of its subsidiaries, affiliated or
related companies, any Company-sponsored employee benefit plan in which Employee
participates and any of its or their respective officers, directors, trustees,
fiduciaries, stockholders, agents, employees, investors, stockholders,
administrators, and their successors and assigns from any claim, duty,
obligation or cause of action relating to any matters of any kind, whether known
or unknown, suspected or unsuspected, that Employee may possess arising from any
omissions, acts or facts that have occurred up until and including the date of
this Agreement, including, without limitation:

(a) any and all claims relating to or arising from Employee’s employment
relationship with the Company and termination of that relationship;

(b) any and all claims relating to, or arising from, Employee’s right to
purchase, or actual purchase of shares of stock of the Company;

(c) any and all claims for personal injury, wrongful discharge of employment,
breach of contract (both express and implied), breach of a covenant of good
faith and fair dealing (both express and implied), negligent or intentional
infliction of emotional distress, negligent or intentional misrepresentation,
negligent or intentional interference with contract or prospective economic
advantage and defamation;

(d) any and all claims for violation of any federal, state or local statute,
including, but not limited to the Title VII of the Civil Rights Act of 1964, the
Civil Rights Act of 1991, the Age Discrimination in Employment Act, the Older
Workers’ Benefits Protection Act, The Americans With Disabilities Act, the
Employee Retirement Income Security Act, the Workers Retraining and Notification
Act, the Fair Labor Standards Act, the Washington Law Against Discrimination and
the Washington Minimum Wage Act;

(e) any and all claims arising out of any other state, federal or local laws and
regulations relating to employment, the payment of wages or employment
discrimination; and

(f) any and all claims for attorney’s fees and costs.

Employee and the Company agree that the release set forth in this Section 4
shall be and shall remain in effect as a complete general release as to the
matters released. This release does not extend to any obligations incurred under
this Agreement or to any rights or claims that may arise after the Effective
Date.

5. Acknowledgement of Wavier of Claims under ADEA. Employee acknowledges that he
is waiving and releasing any rights he may have under the Age Discrimination in
Employment Act of 1967 (“ADEA”) and that this waiver and release is knowing and
voluntary. Employee and the Company agree that this waiver and release does not
apply to any rights or claims that may arise under the ADEA after the Effective
Date. Employee acknowledges that the consideration given for this Agreement is
in addition to anything of value to which Employee was already entitled.
Employee further acknowledges

 

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that he has been advised by this writing that: (a) he should consult with and
obtain the advice of an attorney of his choice prior to executing this
Agreement; (b) he has twenty-one (21) days in which to consider this Agreement;
(c) he has seven (7) days following executing this Agreement to revoke this
Agreement (the “Revocation Period”); and (d) this Agreement shall not be
effective until the Revocation Period has expired. Any revocation should be in
writing and delivered to Chris Pawlowicz at the Company at the following
address: Seattle Genetics, Inc., 21823 - 30th Drive S.E., Bothell, WA 98021 by
close of business on the seventh (7th) day from the date that Employee signs
this Agreement. Unless revoked in accordance with this Section 5, the Agreement
will become final and irrevocable on the eighth (8th) day following execution of
this Agreement.

6. Confidentiality Agreement. Employee represents and warrants that he has not
breached his obligations to the Company under the terms of the Proprietary
Information and Inventions Agreement previously entered into between Employee
and the Company (the “Proprietary Agreement”). Employee shall continue to
maintain the confidentiality of all confidential and proprietary information of
the Company as provided by the Proprietary Agreement, including the terms of
this Agreement, which agreement shall remain in effect pursuant to its terms. In
the future, Employee agrees to take any actions and to execute any documents
reasonably required to assign inventions or patent applications that are owned
by the Company on which he is an inventor to the Company pursuant to the terms
of the Proprietary Agreement.

7. Miscellaneous.

(a) Amendments and Waivers. Any term of this Agreement may be amended or waived
only with the written consent of the parties.

(b) Sole Agreement. This Agreement constitutes the sole agreement of the parties
and supersedes all oral negotiations and prior writings with respect to the
subject matter hereof, but excluding any existing stock option agreements and
the Proprietary Agreement.

(c) Notices. Any notice required or permitted by this Agreement shall be in
writing and shall be deemed sufficient upon receipt, when delivered personally
or by courier, overnight delivery service or confirmed facsimile, or forty-eight
(48) hours after being deposited in the regular mail as certified or registered
mail (airmail if sent internationally) with postage prepaid, if such notice is
addressed to the party to be notified at such party’s address or facsimile
number as set forth below, or as subsequently modified by written notice.

(d) Choice of Law, Arbitration. The validity, interpretation, construction and
performance of this Agreement shall be governed by the laws of the State of
Washington, without giving effect to the principles of conflict of laws. Any
controversy regarding this Agreement or the breach thereof shall be resolved
exclusively by arbitration in King County, Washington. Arbitration shall be
conducted in accordance with the then-prevailing arbitration rules of Judicial
Dispute Resolution (“JDR”), with one arbitrator appointed by the mutual consent
of the parties or, in the absence of such consent, by application of any party
to JDR. The parties agree to abide by all decisions and awards rendered in such
proceedings. Such decisions and awards rendered by the arbitrator shall be final
and conclusive and may be entered in any court having jurisdiction thereof as a
basis of judgment and of the issuance of execution for its collection. All such
controversies, claims or disputes shall be settled in this manner in lieu of any
action at law or equity; provided, however, that nothing in this section shall
be construed as precluding the Company from bringing an action for injunctive
relief or other equitable relief.

(e) Severability. In the event that any provision hereof becomes or is declared
by a court of competent jurisdiction to be illegal, unenforceable or void, said
provision may be modified by the court to the extent necessary to render it
enforceable and the remainder of this Agreement shall continue in full force and
effect.

 

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(f) Effective Date. This Agreement is effective after it has been signed by both
parties and when eight (8) days have passed since Employee has signed the
Agreement, unless revoked by Employee within seven (7) days after the date the
Agreement was signed by Employee.

(g) Counterparts. This Agreement may be executed in counterparts, and each
counterpart shall have the same force and effect as an original and shall
constitute an effective, binding agreement on the part of each of the
undersigned.

(h) Voluntary Execution of Agreement. This Agreement is executed voluntarily and
without any duress or undue influence on the part or behalf of the parties
hereto. The parties acknowledge that:

They have read this Agreement;

They have been represented in the preparation, negotiation, and execution of
this Agreement by legal counsel of their own choice or that they have
voluntarily declined to seek such counsel;

They understand the terms and consequences of this Agreement and of the releases
it contains, and

They are fully aware of the legal and binding effect of this Agreement.

Employee acknowledges and agrees that he has been given at least twenty-one
(21) days to decide whether to sign this Agreement, and has signed it only after
full reflection and analysis. Employee further acknowledges that Employee has
been encouraged to obtain an attorney’s independent counsel and advice, and that
Employee has read and understands the complete Agreement. By signing this
Agreement prior to the expiration of the twenty-one (21) day period set forth in
Section 5 herein, Employee acknowledges and agrees that he had adequate time and
opportunity to fully consider his rights and this release of them.

[Signature Page Follows]

 

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The parties have executed this Agreement on the respective dates set forth
below.

 

COMPANY: SEATTLE GENETICS, INC. By:  

/s/ Clay B. Siegall

Its:   President and CEO

Address:   21823 30th Drive SE   Bothell, WA 98021 Date:  2/21/2012   EMPLOYEE:
Bruce J. Seeley

/s/ Bruce J. Seeley

Signature     Address:   Date:  2/23/2012