Exhibit 10.5

GUARANTY

The undersigned, deCODE Genetics, Inc. and MediChem Life Sciences, Inc.
(collectively “Guarantor”), to induce Woodridge Holdings LLC (“Landlord”) to
execute that certain Lease Agreement between Landlord and deCODE Chemistry, Inc.
(“Tenant”) dated as of June 8, 2007 (the “Lease”) and as a material
consideration and inducement therefore (recognizing that without execution of
this guaranty, Landlord would not be wiling to enter into or make the Lease with
Tenant and recognizing that since Tenant is affliated with Guarantor, the Lease
is of direct benefit to Guarantor) hereby unconditionally guarantees the
performance and observance by Tenant of all the obligations, covenants and
agreements provided in the Lease, as same may be amended from time to time, to
be performed or observed by Tenant during the term of the Lease (including
specifically and without limiting the generality of the foregoing, payment by
Tenant of all rent and other amounts which may be or become due from Tenant
under the Lease).

This Guaranty is an absolute and unconditional Guaranty of payment and
performance. It shall be enforceable against the Guarantor without the necessity
for any suit or proceedings on the Landlord’s part of any kind or nature
whatsoever against the Tenant and without the necessity of any notice of
non-payment, non-performance or non-observance or of any notice of acceptance of
this Guaranty or of any other notice or demand to which the Guarantor might
otherwise be entitled, all of which the Guarantor hereby expressly waives. The
Guarantor hereby expressly agrees that the validity of this Guaranty and the
obligations of the Guarantor hereunder shall in no manner be terminated,
affected, diminished or impaired by reason of the assertion or the failure to
assert by the Landlord against the Tenant of any of the rights or remedies
reserved to the Landlord pursuant to the provisions of the Lease.

This Guaranty shall be a continuing Guaranty, and the liability of the Guarantor
hereunder shall in no way be affected, modified or diminished by reason of any
assignment, renewal, modification or waiver of or change in any of the terms,
covenants, conditions or provisions of the Lease, or the reason of any extension
of time that may be granted by the Landlord to the Tenant or by reason of any
dealings or transactions or matter or 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 the Lease and under this
Guaranty are intended to be distinct, separate and cumulative and no such right
and remedy therein or herein mentioned is intended to be in exclusion of or a
waiver of any of the others.

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

1

--------------------------------------------------------------------------------

within the definition of Guarantor as that term is used herein, all obligations
and terms imposed upon Guarantor by this guaranty agreement shall be joint and
several as to all of such guarantors. This Guaranty shall be governed by, and
construed in 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

 

 

2

--------------------------------------------------------------------------------