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                                                                   EXHIBIT 10.41

                              DECODE GENETICS, INC.

                       SERIES B PREFERRED STOCK AGREEMENT

     This Series B Preferred Stock Agreement (this "Agreement") is made as of
March 1, 2000 (the "Effective Date") by and between deCODE genetics, Inc., a
Delaware corporation (the "Company"), and Kari Stefansson (the "Seller").

                             PRELIMINARY STATEMENTS

     A.   The Company and the Seller entered into a Common Stock Repurchase
Agreement, dated July 12, 1999 (the "Common Repurchase Agreement"), pursuant to
which the Company purchased 333,333 shares of Common Stock from the Seller in
exchange for 250,000 shares of Series B Preferred Stock (the "Series B Shares").

     B.   The Company repurchased the Series B Shares, at a closing held on
August 8, 1999 (the "Closing Date"), for a purchase price per share which the
parties agreed would be equal to the price per share, net of commissions and
other fees payable to the purchaser (the "Purchaser"), at which the Company sold
shares of its Series B Preferred Stock pursuant to a stock purchase agreement
dated as of June 30, 1999 (the "Series B Offering").

     C.   On the Closing Date, the Company and the Seller entered into an oral
agreement that if any contingent portion of the purchase price in the Series B
Offering became payable, the purchase price for the Series B Shares would be
adjusted upward accordingly, with the amount of such adjustment to be paid to
the Seller by the Company after such contingent portion of the purchase price in
the Series B Offering became payable.

     D.   The Company and the Purchaser have entered into an Addendum to Stock
Purchase Agreement confirming that on December 28, 1999, they agreed that a
contingent payment of $7.50, less commissions and other fees payable to the
Purchaser in an amount equal to seven percent (7%) of the sum of the original
purchase price and the contingent payment, was due and payable.

     NOW, THEREFORE, the parties hereto, intending to be legally bound, agree as
follows:

     1.   ADJUSTMENT TO PURCHASE PRICE; PAYMENT OF DEFICIENCY. The adjusted
purchase price for the Series B Shares as of the Closing Date is US$13.95 per
share. Within five business days of the Effective Date, the Company shall pay to
the Seller, by check or wire transfer to such account as the Seller shall
designate, US$6.45 (representing the adjusted purchase price of US$13.95 less
the US$7.50 already paid) for each of the Series B Shares sold to the Company by
the Seller on the Closing Date.

     2.   MISCELLANEOUS. This Agreement shall be governed by and construed under
the laws of the State of Delaware as applied to agreements among Delaware
residents made and to be performed entirely within the State of Delaware. Except
as otherwise expressly provided herein, the provisions hereof shall inure to the
benefit of, and be binding upon, the successors, assigns, heirs, executors,



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and administrators of the parties hereto. This Agreement constitutes the full
and entire understanding and agreement among the parties with regard to the
subject matter hereof. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

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     This Agreement is hereby executed to be effective as of the date first
above written.

                                 deCODE genetics, Inc.



Dated: 1/3/00                    By:  /S/ Hannes T. Smarason
                                      Hannes T. Smarason,  Senior Vice President
                                      & Chief Business Officer




Dated:                           /s/ Kari Stefansson
                                 Kari Stefansson

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