Document:

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                                                                   Exhibit 10.55

                           NONRECOURSE PROMISSORY NOTE

$1,694,875                                                    Reykjavik, Iceland
                                                               21 December, 2000

         FOR VALUE RECEIVED, the undersigned hereby unconditionally promises to
pay to the order of deCODE genetics, Inc., a Delaware corporation (the
"Company"), at the Company's principal office or at such other place as the
holder hereof may designate in writing, on 1 September 2004, in lawful money of
the United States of America and in immediately available funds, the total price
of 1,694,875 Dollars ($1,694,875) together with interest, compounded annually,
from the date hereof on the unpaid principal at the rate of 6% per annum.

         This Note may not be prepaid.

         The full amount of this Note is secured by a pledge of shares of Common
Stock of the Company, and is subject to all of the terms and provisions of the
Early Exercise Stock Purchase Agreement and the Pledge Agreement, each of even
date herewith between the undersigned and the Company. The Company's recovery
against the undersigned for failure to pay any amount owing hereunder when due
shall be limited solely to the shares of Common Stock or other collateral of the
undersigned pledged to the Company in the Pledge Agreement. The undersigned
shall not be liable or have any personal liability in any other respect for the
payment of any amount due under this Note.

         The undersigned hereby represents and agrees that the amounts due under
this Note are not consumer debt, and are not incurred primarily for personal,
family or household purposes, but are for business and commercial purposes only.

         The undersigned hereby waives presentment, protest and notice of
protest, demand for payment, notice of dishonor and all other notices or demands
in connection with the delivery, acceptance, performance, default or endorsement
of this Note.

                                      -1-

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         This Note shall be governed by, and construed, enforced and interpreted
in accordance with, the laws of the State of Delaware, excluding conflict of
laws principles that would cause the application of laws of any other
jurisdiction.

                                             /s/ Einar Stefansson
                                            ------------------------------------
                                                 (signature)

                                                 Einar Stefansson
                                            ------------------------------------
                                                  (print name)

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                                                                   Exhibit 10.56

                                                        [deCODE GENETICS LOGO]

                                                        Lynghalsi 1
                                                        IS-110 Reykjavik
                                                        ICELAND
                                                        Phone: +354 570 1900
                                                        Fax: +354 570 1981
                                                        E-mail: info@decode.is
                                                        Web Page: www.decode.com

December 30, 2000

Chung Tung Augustine Kong
5527 University Avenue, Apartment 4W
Chicago,  IL 60637
USA

Dear Augie:

I am pleased to confirm that deCODE genetics, Inc. is offering you a position as
a Vice President, Statistics. In this position, your major responsibilities
would be to oversee the activities of the team of deCode's statisticians in
Iceland and Boston. This arrangement would begin on or about January 1, 2001.

In exchange for your services, you will receive the following compensation:

1.   Base salary at an annual rate of $143,000, payable from the United States
     into an account that you'll indicate to us. Bank details: Hyde Park
     Bank, 1525 East 53d Street, Chicago, Il 60615 (773-752-4600). Account No:
     071004022:4468554

2.   Participate in deCODE's stock option plan, as determined by the Board, with
     an initial option grant to purchase 80,000 shares of common stock, which
     will vest over a four-year period, subject to approval by the Compensation
     Committee of the Board at an exercise price determined by the Board (which
     will be equal to the fair market value of the common stock on the date of
     the grant by the Compensation Committee), in addition to the stock option
     you've already been granted.

3.   Participate in deCODE's benefit plans that deCODE provides to its U.S.
     employees.

4.   So long as reasonably comparable health insurance coverage is not provided
     to you by deCODE, deCODE will reimburse you (or pay directly to your
     current employer on your behalf, as you and your current employer may
     agree) for the cost to you of all health, dental and hospital insurance
     benefits to which you are entitled from your current employer under the
     U.S. federal law popularly known as COBRA.

5.   deCODE, or an appropriate subsidiary, will provide office space in Boston,
     Massachusetts to be the primary location for you and your department.
     However, you will travel to Iceland, as deemed necessary by deCODE, to
     perform your responsibilities for deCODE.

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6.   deCODE will maintain an apartment in Iceland for your use during the
     periods that you are working in Iceland on behalf of deCODE.

7.   deCODE will provide you with up to $150,000 of funding for your use in
     sponsoring research or establishing collaborations with academic
     institutions on behalf of deCODE, subject to satisfactory terms and
     conditions being reached between deCODE and such academic institutions.

This letter is not an employment contract and you will be an employee at-will.
Therefore, either you or deCODE will have the right to terminate your employment
at will, with or without cause, at any time.

Sincerely yours, deCODE genetics, Inc.

/s/ Kari Stefansson
------------------------------------
Dr. Kari Stefansson
President and Chief Executive Officer<PAGE>   1
                                                                   Exhibit 10.57

                                    EMPLOYEE
                      CONFIDENTIALITY, INVENTION ASSIGNMENT

                            AND NON-COMPETE AGREEMENT

         THIS EMPLOYEE CONFIDENTIALITY, INVENTION ASSIGNMENT AND NON-COMPETE
AGREEMENT ("Agreement") is made as of January 1, 2001, between deCODE genetics,
Inc. (the "Company"), and C. Augustine Kong ("Employee").

         In consideration of the Employee's employment or continued employment
by the Company, with the intention that this Agreement shall apply to the entire
period of Employee's employment with the Company (including the period prior to
the date of this Agreement), the Employee hereby agrees as follows:

1. CONFIDENTIAL INFORMATION DEFINED. "Confidential Information" means trade
secrets, proprietary information, and confidential knowledge and information
which includes, but is not limited to, matters of a technical nature (such as
discoveries, ideas, concepts, designs, drawings, specifications, techniques,
models, diagrams, test data, scientific methods and know-how), and matters of a
business nature (such as the identity of customers and prospective customers,
the nature of work being done for or discussed with customers or prospective
customers, suppliers, marketing techniques and materials, marketing and
development plans, pricing or pricing policies, financial information, plans for
further development, and any other information of a similar nature not available
to the public).

2. NON-DISCLOSURE OF CONFIDENTIAL INFORMATION OF THE COMPANY. Employee
acknowledges that, during the period of Employee's employment with the Company,
Employee has had or will have access to Confidential Information of the Company.
Therefore, Employee agrees that both during and after the period of Employee's
employment with the Company, Employee shall not, without the prior written
approval of the Company, directly or indirectly (a) reveal, report, publish,
disclose or transfer any Confidential Information the Company to any person or
entity, or (b) use any Confidential Information of the Company for any purpose
or for the benefit of any person or entity, except as may be necessary in the
performance of Employee's work for the Company.

3. NON-DISCLOSURE OF CONFIDENTIAL INFORMATION OF OTHERS. Employee acknowledges
that, during the period of Employee's employment with the Company, Employee may
have had or will have access to Confidential Information of third parties who
have given the Company the right to use such Confidential Information, subject
to a non-disclosure agreement between the Company and such third party.
Therefore, Employee agrees that both during and after the period of Employee's
employment with the Company, Employee shall not, without the prior written
approval of the Company, directly or indirectly (a) reveal, report, publish,
disclose or transfer any Confidential Information of such third parties to any
person or entity, or (b) use any Confidential Information of such third parties
for any purpose or for the benefit of any person or entity, except as may be
necessary in the performance of Employee's work for the Company.

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4. PROPERTY OF THE COMPANY. Employee acknowledges and agrees that all
Confidential Information of the Company and all reports, drawings, blueprints,
data, notes, and other documents and records, whether printed, typed,
handwritten, videotaped, transmitted or transcribed on data files or on any
other type of media, made or compiled by Employee, or made available to
Employee, during the period of Employee's employment with the Company (including
the period prior to the date of this Agreement) concerning the Company's
Confidential Information are and shall remain the Company's property and shall
be delivered to the Company within five (5) business days after the termination
of such employment with the Company or at any earlier time on request of the
Company. Employee shall not retain copies of such Confidential Information,
documents and records.

5. PROPRIETARY NOTICES. Employee shall not, and shall not permit any other
person to, remove any proprietary or other legends or restrictive notices
contained in or included in any Confidential Information.

6.       INVENTIONS.

         (a) Employee shall promptly, from time to time, fully inform and
disclose to the Company in writing all inventions, copyrightable material,
designs, improvements and discoveries of any kind which Employee now has made,
conceived or developed (including prior to the date of this Agreement), or which
Employee may later make, conceive or develop, during the period of Employee's
employment with the Company, which pertain to or relate to the Company's
business or any of the work or businesses carried on by the Company
("Inventions"). This covenant applies to all such Inventions, whether or not
they are eligible for patent, copyright, trademark, trade secret or other legal
protection; and whether or not they are conceived and/or developed by Employee
alone or with others; and whether or not they are conceived and/or developed
during regular working hours; and whether or not they are conceived and/or
developed at the Company's facility or not.

         (b) All Inventions shall be the sole and exclusive property of the
Company, and shall be deemed part of the Confidential Information of the Company
for purposes of this Agreement, whether or not fixed in a tangible medium of
expression. Employee hereby assigns all Employee's rights in all Inventions and
in all related patents, copyrights and trademarks, trade secrets and other
proprietary rights therein to the Company. Without limiting the foregoing,
Employee agrees that any copyrightable material shall be deemed to be "works
made for hire" and that the Company shall be deemed the author of such works
under the United States Copyright Act, provided that in the event and to the
extent such works are determined not to constitute "works made for hire",
Employee hereby irrevocably assigns and transfers to the Company all right,
title and interest in such works.

         (c) Employee shall assist and cooperate with the Company, both during
and after the period of Employee's employment with the Company, at the Company's
sole expense, to allow the Company to obtain, maintain and enforce patent,
copyright, trademark, trade secret and other legal protection for the
Inventions. Employee shall sign such documents, and do such things necessary, to
obtain such protection and to vest the

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Company with full and exclusive title in all Inventions against infringement by
others. Employee hereby appoints the Secretary of the Company as Employee's
attorney-in-fact to execute documents on Employee's behalf for this purpose.

         (d) Employee shall not be entitled to any additional compensation for
any and all Inventions made during the period of Employee's employment with the
Company.

7. COVENANT NOT TO COMPETE. Employee and the Company agree that the services
rendered by the Employee are unique and irreplaceable, and that competitive use
and knowledge of any Confidential Information would substantially and
irreparably injure the Company's business, prospects and good will. Employee and
the Company also agree that the Company's business is global in nature due to
the type of products and/or services being provided. Therefore, Employee agrees
that during the period of Employee's employment with the Company and for a
period of two (2) years thereafter, Employee shall not, directly or indirectly,
through any other person, firm, corporation or other entity (whether as an
officer, director, employee, partner, consultant, holder of equity or debt
investment, lender or in any other manner or capacity):

         (a) sell, market, offer to sell products and/or services anywhere in
the world similar to that being developed, offered or sold by the Company on the
date of the termination of Employee's employment with the Company for any
reason;

         (b) solicit, induce, encourage or attempt to induce or encourage any
employee or consultant of the Company to terminate his or her employment or
consulting relationship with the Company, or to breach any other obligation to
the Company;

         (c) solicit, interfere with, disrupt, alter or attempt to disrupt or
alter the relationship, contractual or otherwise, between the Company and any
other person including, without limitation, any consultant, contractor,
customer, potential customer, or supplier of the Company; or

         (d) engage in or participate in any business conducted under any name
that shall be the same as or similar to the name of the Company or any trade
name used by the Company.

         Employee acknowledges that the foregoing geographic, activity and time
limitations contained in this Section 7 are reasonable and properly required for
the adequate protection of the Company's business. In the event that any such
geographic, activity or time limitation is deemed to be unreasonable by a court,
Employee shall submit to the reduction of either said activity or time
limitation to such activity or period as the court shall deem reasonable. In the
event that Employee is in violation of the aforementioned restrictive covenants,
then the time limitation thereof shall be extended for a period of time equal to
the pendency of such proceedings, including appeals.

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8. REPRESENTATIONS. Employee represents that Employee has the right to enter
into this Agreement, and that Employee's performance of all the terms of this
Agreement and his duties as an employee of the Company will not breach any
confidential information agreement, non-competition agreement or other agreement
with any former employer of his services, either as an employee, consultant,
contractor or independent contractor, or with any other party. Employee
represents that Employee will not disclose to the Company any trade secrets or
confidential or proprietary information of any third party that are not
generally available to the public.

9. DISCLOSURE OF THIS AGREEMENT. Employee hereby authorizes the Company to
notify others, including but not limited to customers of the Company and any of
Employee's future employers, of the terms of this Agreement and Employee's
responsibilities under this Agreement.

10. SPECIFIC PERFORMANCE. Employee acknowledges that money damages alone would
not adequately compensate the Company in the event of a breach or threatened
breach by Employee of this Agreement, and that, in addition to all other
remedies available to the Company at law or in equity, the Company shall be
entitled to injunctive relief for the enforcement of its rights and to an
accounting of profits made during the period of such breach.

11. NO RIGHTS GRANTED. Employee understands that nothing in this Agreement shall
be deemed to constitute, by implication or otherwise, the grant by the Company
to the employee of any license or other right under any patent, patent
application or other intellectual property right or interest belonging to the
Company.

12.      SEVERABILITY.

         (a) Each of the covenants provided in this Agreement are separate and
independent covenants. If any provision of this Agreement shall be determined to
be invalid or unenforceable, the remainder of this Agreement shall not be
affected thereby and any such invalid or unenforceable provision shall be
reformed so as to be valid and enforceable to the fullest extent permitted by
law.

         (b) It is not a defense to the enforcement of any provision of this
Agreement that the Company has breached or failed to perform any obligation or
covenant hereunder or under any other agreement or understanding between
Employee and the Company.

13. GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware without regard to conflict of
law rules.

14. SUPERSEDES OTHER AGREEMENTS. This Agreement contains the entire agreement of
the parties with respect to subject matter hereof and supersedes all previous
agreements and understandings between the parties with respect to its subject
matter.

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15. AMENDMENTS. This Agreement may not be changed, modified, released,
discharged, abandoned or otherwise terminated in whole or in part except by an
instrument in writing, agreed to and signed by the Employee and a duly
authorized officer of the Company.

16. ACKNOWLEDGEMENTS. THE EMPLOYEE ACKNOWLEDGES THAT (i) THE EMPLOYEE HAS READ
AND FULLY UNDERSTANDS THIS AGREEMENT; (ii) THE EMPLOYEE HAS BEEN GIVEN THE
OPPORTUNITY TO ASK QUESTIONS; (iii) THE EMPLOYEE HAS RECEIVED A COPY OF THIS
AGREEMENT, THE ORIGINAL OF WHICH WILL BE RETAINED IN THE EMPLOYEE'S PERSONNEL
FILE; AND (iv) THE EMPLOYEE'S OBLIGATIONS UNDER THIS AGREEMENT SURVIVE THE
TERMINATION OF THE EMPLOYEE'S EMPLOYMENT WITH THE COMPANY FOR ANY REASON.

                                      * * *

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                           deCODE genetics, Inc.

                                           By: /s/ Kari Stefansson
                                               ---------------------------------

                                           Name: Kari Stefansson
                                                 -------------------------------

                                           Title: President & CEO
                                                 -------------------------------

WITNESS OR ATTEST:                         EMPLOYEE:  /s/ Augustine Kong
                                                      --------------------------

/s/ Tanya Zharov                           Name:    C. Augustine Kong
------------------------------                      ----------------------------
   Corporate Counsel
          of                               Address:
  deCODE genetics, Inc.                             ----------------------------

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