                                                                    EXHIBIT 10.5
                                                                    ------------

                                    AGREEMENT
                           ON THE OBLIGATION TO ACCEPT
                                 A PUBLIC OFFER

between

Adsero Corp., 2101 Nobel Street, Sainte Julie, Quebec, J3E 1Z8 and or its
designates, collectively the "Buyer",

and

Holger Brueckmann-Turbon c/o Turbon AG, Ruhrdeich 10, D-45525 Hattingen,
Germany, the "VENDOR".

In the following, Buyer and Vendor are individually referred to as the "PARTY",
and jointly as the "PARTIES".

PREAMBLE

Turbon AG is a stock corporation established in accordance with German law with
seat in Hattingen, registered in the commercial register of the local court of
Essen under HRB 15780. The total share capital of Turbon AG amounts to EURO
10,299,974.95, divided into 4,029,000, shares (the "SHARES"). The shares are
listed and traded on the Frankfurt stock exchange.

The Vendor holds 1,059,000 shares in Turbon AG the "VENDOR SHARES". He intends
to sell the Vendor Shares to the Buyer if the Buyer should decide to submit a
public offer ("OFFER") for the acquisition of the shares according to the terms
of the Securities Acquisition and Takeover Act (Wertpapiererwerbs- und
Ubernahmegesetz, "WPUG"). The Buyer has not yet taken a decision concerning the
submission of such an Offer. Having said this, the Parties conclude the
following Agreement ("AGREEMENT"):

1.       OBLIGATION TO ACCEPT AN OFFER

1.1      If the Buyer, or a person designated by the Buyer, submits an Offer,
         the Vendor is obliged to immediately accept the Offer in accordance
         with the terms of the Offer and to transfer the Vendor Shares to the
         Buyer, or the person designated by the Buyer, provided that (a) the
         price offered for the Shares is at least US$14 per share payable in
         cash (b) NCR has waived any rights they may have related to ss.4 of the
         shareholders agreement referenced in Section 3.1.2 hereof and (c)
         Adsero has entered into an agreement regarding the purchase of 400,000
         treasury shares of Turbon AG.

1.2      Under no circumstances is the Buyer obliged to submit an Offer.

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2.       PERIOD OF VALIDITY

The obligations arising out of this Agreement - with the exception of those
listed in Clause 6 - will automatically end if the Buyer has not published an
Offer document in accordance with the WpUG concerning the acquisition of Shares
in AG and approved by the German Financial Supervisory Authority (Bundesanstalt
fur Finanzdienstleistungsaufsicht) by September 30, 2005, 12 p.m. The Parties
may extend the period of validity at any time by mutual agreement in writing.

3.       VENDOR WARRANTIES

3.1      With effect as per today and as per the day of transfer of the Vendor
         Shares to the Buyer, the Vendor warrants the following:

3.1.1    The Vendor has sole, unencumbered and unrestricted title to the Vendor
         Shares and the Vendor Shares are not encumbered with any rights of
         third parties

3.1.2    the Vendor Shares are not subject to any rights of first refusal by
         other shareholders or third parties except as contained in a
         shareholders agreement between the Vendor and NCR related to a first
         right of refusal. The Vendor represents that this agreement has been
         discussed with NCR. Therefore the provision related to the first right
         of refusal will be considered nul and void as a result of this
         agreement, and

3.1.3    the Vendor may freely dispose of the Vendor Shares.

3.2      The Vendor does not give any warranties extending beyond the warranties
         in sub-clause 0.

4.       NOTIFICATIONS

         All notifications and statements under or in connection with this
         Agreement require written form to be effective. They must be faxed to
         the following numbers:

4.1      for the Buyer to:

         Adsero Corp., 2101 Nobel Street, Sainte Julie, Quebec, Canada, J3E 1Z8,

         Fax # 416-467-7173

         Attention: William Smith, CFO, Adsero Corp.

4.2      for the Vendor to:

         Holger BrueckmannTurbon, c/o Turbon AG, Ruhrdeich 10, D-45525
         Hattingen, Germany

         Fax # 49 (0) 23 24/504-156

         Attention: Mr. Holger Brueckmann- Turbon

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         or to other persons or addresses which are communicated by the
         respective Party.

5.       COSTS

         Each Party bears its own costs in connection with the preparation,
         assessment or conclusion of the Agreement, including the costs for
         legal, commercial, financial or tax advice.

6.       FINAL PROVISIONS

6.1      This Agreement contains the entire agreement reached between the
         Parties on the subject of this Agreement. There are no side agreements.

6.2      Amendments and supplements to this Agreement as well as the waiver of
         any rights under this Agreement must be in writing in order to be
         valid. This also applies to any amendment to, or cancellation of, this
         written form clause.

6.3      Exclusive place of jurisdiction is Frankfurt.

6.4      This Agreement is governed by German law.

6.5      Should a provision of this Agreement or a provision later on included
         in this Agreement be or become null and void as a whole or in part, or
         should a gap in this Agreement become evident, this does not affect the
         validity of the remaining provisions. Instead of the null and void
         provision, or in order to fill the gap, such valid and practicable
         regulation is deemed to be agreed with effect ex tunc that in legal and
         economic terms comes closest to what the Parties intended or would have
         intended in accordance with the purpose of this Agreement if they had
         considered the point at the time of conclusion of this Agreement. If
         the nullity of a provision is due to a degree of performance or time
         (period or deadline) laid down in this provision, then the provision is
         deemed to be agreed with a legally permissible degree that comes
         closest to the original degree. [The Parties are aware of the decision
         of the Federal Supreme Court (Bundesgerichtshof) of 24 September 2002.
         However, it is the express intention of the Parties that this
         sub-clause 1.6 does not merely result in a reversal of the burden of
         proof but that section 139 Civil Code is contracted out as a whole.]

         Date: June 21, 2005            Date: June 21, 2005

         For: Adsero Corp.

         /s/ William Smith              /s/ Holger Brueckmann-Turbon
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         William Smith                  Holger Brueckmann-Turbon


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