Exhibit 10.28
 
April 22, 2002
 
Eric (Rick) Mueninghoff
1981 Robin Ridge Court
Walnut Creek, CA 94596
 
Dear Rick:
 
This Letter Agreement describes our understanding and agreements regarding the
termination of your employment relationship with RITA Medical Systems, Inc. (the
“Company”). By your signature below, you acknowledge and agree with the
following:
 
1.    Separation Date and Final Salary Payment.    Your employment relationship
with the Company will terminate on April 23, 2002 (the “Separation Date”). As of
the Separation Date you will receive all salary due to you to as of the
Separation Date (including payment for any accrued and unused vacation as of the
Separation Date).
 
2.    Separation Benefits.    In consideration for your release of claims as set
forth below and your other obligations set forth herein, and provided that you
sign the acknowledgement and agreement below signifying your agreement to the
terms of this Letter Agreement, including the release of claims, and return the
signed letter to me and all company property in your possession no later than
5:00 p.m. on May 22, 2002, and provided further that you do not exercise your
right to revoke this Letter Agreement under Paragraph 6 below, the Company will
provide the following:
 
(a)  Salary Continuation.    The Company will continue to pay you your regular
salary as of April 23, 2002 less authorized and required deductions; for a
period of two months, until June 30, 2002. These salary continuation payments
shall be paid in semi-monthly installments on Company regular paydays. The first
payment shall be made on the first regular payroll date following the end of the
Revocation Period described in Paragraph 6 below.
 
(b)  Stock Options.    Continuation of your stock option vesting through June
30, 2002.
 
3.    Insurance Benefits.    You will continue to receive the Company’s health
insurance benefits (medical, dental and vision) at the Company’s expense until
June 30, 3002, which date shall be the “qualifying event” date under the
Consolidated Omnibus Budget Reconciliation Act of 1985, as amended (“COBRA”).
Following such date, you have the right to continue the health insurance
coverage under COBRA at your own expense.
 
4.    Nondisclosure of Confidential and Proprietary Information.    You
acknowledge and agree to continue to maintain the confidentiality of all
confidential and proprietary information of the Company as provided by the
Confidential Information and Inventions Assignment Agreement previously entered
into between you and the Company, a copy of which is attached hereto as Exhibit
A (the “Confidentiality Agreement”), and that such Confidentiality Agreement
shall remain in full force and effect notwithstanding this Letter Agreement.

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5.    Release of Claims.
 
(a)  You acknowledge and agree that the foregoing consideration represents
settlement in full of all outstanding obligations owed to you by the Company. On
behalf of yourself, and your heirs, executors, successors and assigns, you agree
to hereby fully and forever release the Company and its officers, directors,
employees, investors, shareholders, administrators, predecessor and successor
corporations 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 you may possess arising from any omissions, acts or facts that
have occurred up until and including the date you sign this Letter Agreement
under any and all applicable state and federal laws including, without
limitation:
 
(i)  any and all claims relating to or arising from your employment relationship
with the Company and termination of that relationship;
 
(ii)  any and all claims relating to, or arising from, your right to purchase,
or actual purchase of shares of stock of the Company;
 
(iii)  any and all claims for 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;
 
(iv)  any and all claims for violation of any federal, state or municipal
statute, including, but not limited to, Title VII of the Civil Rights Act of
1964, Americans with Disabilities Act, the Age Discrimination in Employment Act
of 1967 (up to and including the date you sign this Letter Agreement), the
California Fair Employment and Housing Act, and any and all claims arising out
of any other laws and regulations relating to employment or employment
discrimination; and
 
(vi)  any and all claims for attorney’s fees and costs.
 
You agree that the release set forth in this Paragraph 5(a) will be and remain
in effect in all respects as a complete and general release as to the matters
released. This release does not extend to any obligations incurred under this
Letter Agreement.
 
(b)  Except as otherwise provided above in Paragraph 3, you acknowledge and
agree that you will not be entitled to participate in any of the Company’s
benefit plans or programs offered to employees of the Company, including, but
not limited to, any accrual of vacation, after the Separation Date.
 
        6.    Acknowledgment of Waiver of Claims under ADEA.    You acknowledge
that you are waiving and releasing any rights you may have under the Age
Discrimination Act of 1967 (“ADEA”) and that this waiver and release is knowing
and voluntary. You and the Company agree that this waiver and release does not
apply to any rights or claims that may arise under ADEA after the date you
execute this

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Letter Agreement. You acknowledge that the consideration given for the waiver
and release in this Letter Agreement is in addition to anything of value to
which you were already entitled. You further acknowledges that you has been
advised by this writing that (a) you should consult with an attorney prior to
executing this Letter Agreement; (b) you have at least twenty-one (21) days
within which to consider this Letter Agreement; (c) you have seven (7) days
following your execution of this Letter Agreement to revoke the Letter Agreement
(the “Revocation Period”); and (d) this Letter Agreement shall not be effective
until the Revocation Period has expired.
 
7.    Civil Code Section 1542.    You and the Company (“we”) each represent to
the other that we are not aware of any claim by either of us other than the
claims that are released by Paragraph 5 of this Letter. We each acknowledge that
we are familiar with the provisions of California Civil Code Section 1542, which
provides as follows:
 
A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR
SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF EXECUTING THE RELEASE, WHICH IF
KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED HIS SETTLEMENT WITH THE DEBTOR.
 
We, each being aware of such code section, agree to waive any rights we may have
thereunder, as well as under any other statute or common law principles of
similar effect.
 
8.    Breach of Confidentiality Obligations.    You acknowledge that upon breach
of any of the confidentiality provisions contained in Paragraph 4 of this Letter
Agreement, the Company would sustain irreparable harm from such breach, and,
therefore, you agree that in addition to any other remedies which the Company
may have for any breach of the obligations set forth in this Letter Agreement or
the Confidentiality Agreement, the Company will be entitled to obtain equitable
relief, including specific performance and injunctions, restraining you from
committing or continuing any such violation of this Letter Agreement or the
Confidentiality Agreement.
 
9.    Non-Disparagement.    The undersigned each agree to refrain from any
disparagement, criticism, defamation, slander of the other, or interference with
the contracts and relationships of the other, and the undersigned each represent
and warrant that they have not disparaged, criticized, defamed, slandered the
other, or interfered in any manner with the contracts and relationships of the
other prior to the Separation Date.
 
        10.    Arbitration.    The undersigned each agree to attempt to settle
all disputes arising in connection with this Agreement through good faith
consultation. In the event no agreement can be reached on such dispute within
fifteen (15) days after notification in writing by either party to the other
concerning such dispute, the dispute shall be settled by binding arbitration to
be conducted in Santa Clara County, California before the American Arbitration
Association under its under its California Employment Dispute Resolution Rules,
or by a judge to be mutually agreed upon. The arbitration decision shall be
final, conclusive and binding on both parties and any arbitration award or
decision may be entered in any court having jurisdiction. The undersigned each
agree that the prevailing party in any arbitration shall be entitled to
injunctive relief in any court of competent jurisdiction to enforce the
arbitration award and that the prevailing party in any such proceeding shall be
awarded reasonable

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attorneys’ fees and costs. This Paragraph 10 shall not apply to the
Confidentiality Agreement. The undersigned hereby waive any rights they may have
to trial by jury in regard to arbitrable claims.
 
11.    Voluntary Execution of Agreement.    You acknowledge that this Letter
Agreement is executed by you voluntarily, with the full intent of releasing all
claims against the Company and without any duress or undue influence. You
further acknowledge that (i) you have read this entire Letter Agreement, (ii)
you understand the terms and consequences of this Letter Agreement and of the
releases it contains, and you have been advised that you may seek legal
representation with respect to the matters contained in this Letter Agreement;
and (iii) you are fully aware of the legal and binding effect of this Letter
Agreement.
 
RITA MEDICAL SYSTEMS, INC.
By:
 
/S/    DONALD STEWART        
   

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Title:
 
Chief Financial Officer
   

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AGREED AND ACKNOWLEDGED:
 
My agreement with the above terms is acknowledged by my signature below.
Furthermore, I acknowledge that I have read and understand the foregoing Letter
Agreement and that I sign this release of all claims voluntarily, with full
appreciation that I am forever foreclosed from pursuing any of the rights I have
waived.
 
/S/    ERIC MUENINGHOFF        

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Eric Mueninghoff
Dated:
 
5/22/02

 
 

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EXHIBIT A
 
CONFIDENTIALITY AGREEMENT