**Exhibit10.5**

**GUARANTY**

The undersigned, deCODEGenetics, Inc. and MediChem Life Sciences, Inc. (collectively “Guarantor”), to induce Woodridge HoldingsLLC (“Landlord”) to execute that certain Lease Agreement between Landlord and deCODE Chemistry, Inc. (“Tenant”) datedas of June 8, 2007 (the “Lease”) and as a material consideration andinducement therefore (recognizing that without execution of this guaranty, Landlord would not bewiling to enter into or make the Lease with Tenant and recognizing that since Tenant is affliatedwith Guarantor, the Lease is of direct benefit to Guarantor) herebyunconditionally guarantees the performance and observance by Tenant of all theobligations, covenants and agreements provided in the Lease, as same may beamended from time to time, to be performedor observed by Tenant during the term of the Lease (including specifically andwithout limiting the generalityof the foregoing, payment by Tenant of all rent and other amounts which may beor become due from Tenant under the Lease).

ThisGuaranty is an absolute and unconditional Guaranty of payment and performance.It shall be enforceableagainst the Guarantor without the necessity for any suit or proceedings on theLandlord’s part of any kind ornature whatsoever against the Tenant and without the necessity of any notice ofnon-payment, non-performance ornon-observance or of any notice of acceptance of this Guaranty or of any othernotice or demand to which the Guarantor might otherwise be entitled, all ofwhich the Guarantor hereby expressly waives. The Guarantor hereby expresslyagrees that the validity of this Guaranty and the obligations of the Guarantorhereunder shall in no manner be terminated, affected, diminished or impaired byreason of the assertion or the failure to assert by the Landlord against the Tenant of any of the rights or remediesreserved to the Landlord pursuant to the provisions of the Lease.

ThisGuaranty shall be a continuing Guaranty, and the liability of the Guarantorhereunder shall in no way be affected, modified or diminished by reasonof any assignment, renewal, modification or waiver of or change in any of theterms, covenants, conditions or provisions of the Lease, or the reason of any extension of time that may be granted by theLandlord to the Tenant or by reason of any dealings or transactions or matteror thing occurring between the Landlord and the Tenant whether or not notice thereof is given to the Guarantor.Furthermore, this Guaranty shall not be revoked by the banptcy or insolvency of the Tenant.

All of the Landlord’s rights and remedies under theLease and under this Guaranty are intended to be distinct, separate andcumulative and no such right and remedy therein or herein mentioned is intendedto be in exclusion of or a waiver of any of the others.

This Guaranty shall inure to the benefit of theLandlord, its successors and assigns and shall be binding on the successors and assigns of theGuarantor. If there is more than one guarantor included

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within the definition ofGuarantor as that term is used herein, all obligations and terms imposed upon Guarantor by this guaranty agreement shall bejoint and several as to all of such guarantors. This Guaranty shall be governed by, and construedin accordance with, the laws of the State of Ilinois.
| Dated: June 8, 2007. |   | GUARANTOR:                    |
|----------------------|--------|-------------------------------|
|                 |   |                          |
|                 |   | deCODE Genetics,  Inc.,       |
|                 |   |                          |
|                 |   | By:                           | /s/ Lance Thibault |   |
|                 |   | Title:                        | CFO and  Treasurer |   |
|                 |   |                          |
|                 |   |                          |
|                 |   | MediChem Life  Sciences, Inc. |
|                 |   |                          |
|                 |   | By:                           | /s/ Chris Tauer |   |
|                 |   | Title:                        | US Controller |   |
|                      |        |                               |  |  |  |  |  |

 

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