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                                                                 Exhibit 10.2(c)

                       ASSIGNMENT AND ASSUMPTION OF LEASE

         THIS ASSIGNMENT AND ASSUMPTION OF LEASE (this "Assignment") is made
effective as of April 16 , 1998, by and between APERTUS TECHNOLOGIES
INCORPORATED, a Minnesota corporation ("Assignor") and Best Buy Co., Inc., a
Minnesota corporation ("Assignee").


                                    RECITALS

         A. Pursuant to an Office/Warehouse Lease dated May 10, 1990, as amended
by Amendment No. 1, dated July 23, 1990, and by a Second Amendment to Lease,
dated February 18, 1996 (said Office/Warehouse Lease, Amendment No. 1 and Second
Amendment to Lease being herein collectively referred to as the "Lease") Real
Estate Income Partners III, Limited Partnership ("Landlord") has leased to
Assignor, as Tenant, demised premises consisting of approximately 76,297 square
feet (the "Demised Premises") being all of the building known as Creekedge
Business Center and located at 7275-7279 Flying Cloud Drive, Eden Prairie,
Minnesota 55344. A true and correct copy of the Lease including all of the
Riders and Exhibits thereto is attached to this Assignment as Exhibit A and
incorporated herein by reference.

         B. The term of the Lease expires on July 31, 2002.

         C. A portion of the Demised Premises (the "Subleased Premises") has
been subleased by Assignor to Famous Dave's of America, Inc., a Minnesota
corporation, (the "Sublessee"), pursuant to a Sublease Agreement dated July 30,
1997 (the "Sublease Agreement") for a term beginning September 1, 1997 and
ending August 31, 2000. A true and correct copy of the Sublease Agreement is
attached to this Assignment as Exhibit B and incorporated herein by reference.

         D. Assignor has agreed to assign to Assignee all of Assignor's right,
title and interest in and to the Lease and the Sublease, upon the terms and
conditions stated herein and subject to Assignor's right to continue in
occupancy and possession of the "Leaseback Premises" as defined in and subject
to the terms and conditions of Paragraph 3 of this Assignment.

         NOW, THEREFORE, in consideration of the foregoing Recitals, and of One
Dollar and other good and valuable consideration, Assignor and Assignee agree as
follows:

         1. INCORPORATION OF RECITALS. Recital Paragraphs A through D, above,
are incorporated in and made a part of this Assignment in their entirety.

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2.       ASSIGNMENT OF LEASE AND SUBLEASE.

a.       Assignor hereby assigns, transfers, sets over and delivers to Assignee,
         effective May 1, 1997 (the "Effective Date") all of Assignor's right,
         title and interest in, to and under the Lease and the Sublease.
         Assignee acknowledges it has received complete copies of the Lease and
         the Sublease and is familiar with all of the terms, covenants,
         conditions and provisions thereof. The assignment of Assignor's right,
         title and interest in the Lease and the Sublease is subject to: i) the
         Sublease and the right, title and interest of the Sublessee thereunder;
         ii) the rights of Assignor with respect to the Leaseback Premises as
         stated in Paragraph 3 of this Assignment; and iii) the consent of the
         Landlord as provided in Paragraph 6 of this Assignment.

b.       Commencing on the Effective date, Assignee shall assume and does hereby
         agree to assume, comply with and perform all of the Assignor's
         liabilities, agreements, undertakings and obligations under and with
         respect to the Lease and the Sublease including, but not limited to,
         payment of all Base Rent, Real Estate Taxes and Operating Expenses (as
         said phrases are defined in the Lease) and other sums due to the
         Landlord, as if Assignee had executed the Lease, as Tenant and the
         Sublease, as Sublessor.

c.       Assignee agrees it shall protect, indemnify and hold Assignor harmless
         from and against any and all claims, liabilities, obligations, legal
         actions, damages, costs and expenses, including reasonable attorneys'
         fees, arising out of or relating to the Lease, the Sublease or the
         Demised Premises which result or arise from any occurrence or event
         occurring from and after the Effective Date with the exception of any
         liabilities of Assignor arising solely under the Leaseback Agreement
         specifie in Paragraph 3 of this Assignment.

d.       Assignor agrees it shall protect, indemnify and hold Assignee harmless
         from and against any and all claims, liabilities, obligations, legal
         actions, damages, costs and expenses, including reasonable attorneys'
         fees, arising out of or relating to the Lease, the Sublease or the
         Demised Premises which result from any occurrence or event occurring
         prior to the Effective Date, including, but not limited to, any
         violations of law, governmental ordinances or codes by Assignor on or
         before the Effective Date.

e.       Subject to obtaining the consent of the Landlord, Assignor warrants
         that it has the right to assign its interest in the Lease and the
         Sublease free from all liens or encumbrances arising through or under
         Assignor other than the Sublease.

f.       On or before the Effective Date, Assignor will obtain an Estoppel
         Certificate from the Sublessee in the form of Exhibit E attached hereto
         and deliver such Estoppel Certificate to Assignee.

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g.       On the Effective Date, Assignor shall assign, transfer and deliver to
         Assignee all of the $17,168.00 security deposit held by Assignor
         pursuant to Paragraph 9 of the Sublease together with any accrued
         interest thereon through the Effective Date which Assignor may be
         obligated to pay with respect to said security deposit under the
         provisions of the Sublease. Upon payment of said security deposit to
         Assignee, Assignee shall be solely responsible for the security deposit
         and shall indemnify and hold Assignor harmless from any and all claims,
         liabilities, damages, costs and expenses related thereto.

         3. LEASEBACK AGREEMENT. From and after the Effective Date, Assignor
shall be entitled to continue in possession and occupancy of a portion of the
Demised Premises consisting of approximately 18,274 square feet as depicted in
Exhibit C attached hereto and incorporated herein by reference (the "Leaseback
Premises") as a Sublessee of Assignee, upon and subject to the following terms
and conditions (the "Leaseback Agreement"):

a.       Assignor shall be entitled to occupy the Leaseback Premises as a
         Sublessee of Assignee's from the Effective Date until September 30,
         1998, subject to Assignor's right to terminate the Leaseback Agreement
         before September 30, 1998, as hereinafter provided.

b.       Assignor shall pay Assignee base rent for the Leaseback Premises in the
         amount of $11,421.25, per month, commencing on May 1, 1998 and
         continuing on the first day of each and every successive month
         thereafter until the termination of the Leaseback Agreement.

c.       Assignor shall also pay Assignee 23.95 percent of each monthly
         installment of "Operating Expenses" and "Real Estate Taxes" (as said
         phrases are defined in the Lease) due to the Landlord with respect to
         the Demised Premises commencing on the Effective Date and terminating
         on the date of termination of the Leaseback Agreement.

d.       From and after the Effective Date, Assignor shall pay all utility
         charges specifically attributable to its use and occupancy of the
         Leaseback Premises. In the event the utilities provided to the
         Leaseback Premises are not separately metered or sub metered for any
         particular utility, from and after the Effective Date Assignor shall
         pay 23.95 percent of the utility charges for the entire Demised
         Premises for the particular utility that is not separately metered or
         submetered.

e.       Assignor agrees that the Leaseback Agreement and its use and possession
         of the Leaseback Premises shall be subject and subordinate to the terms
         of the Lease. Assignee agrees that it shall deliver to Assignor copies
         of all notices, demands or other documents received by Assignee from
         the Landlord relating to any default under the Lease.

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f.       Assignor and Assignee agree Assignor shall be entitled to terminate the
         Leaseback Agreement and Assignor's obligations under this Paragraph 3,
         effective on the last day of any calendar month prior to September 30,
         1998, by serving a notice of termination on Assignee no later the 15th
         day of the calendar month in which the Leaseback Agreement and
         Assignor's obligations under this Paragraph 3 are to terminate. Upon
         service of such notice of termination, the Leaseback Agreement and all
         of Assignor's obligations under this Paragraph 3 shall terminate on the
         last day of such calendar month.

g.       Assignor and Assignor's employees and invitees shall be entitled to use
         forty-five (45) parking spaces in the parking lot adjacent to the
         Leaseback Premises. Assignor and Assignor's employees and invitees
         shall also be entitled to use ten (10) visitor and handicap spaces in
         that portion of the parking lot adjacent to the main entrance of the
         Leaseback Premises to be shared between Assignor and Assignee. Assignor
         shall also have unrestricted access to the loading docks serving the
         Leaseback Premises.

h.       The base rent, Real Estate Taxes and Operating Expenses payable to
         Assignee under this Paragraph 3 shall be payable to Assignee at: 7075
         Flying Cloud Drive, Eden Prairie, Minnesota 55344, Attention: Lease
         Administration, and shall be received on or before the due date
         therefore.

         4. DELIVERY OF DEMISED PREMISES.

a.       On the Effective Date, Apertus shall deliver the Demised Premises,
         other than the Subleased Premises and the Leaseback Premises, to
         Assignee, and Assignor shall remove all of Assignor's personal property
         therefrom. Assignor shall also surrender the Leaseback Premises to
         Assignee at the end of the term of the Leaseback Agreement, as provided
         in Paragraph 3 of this Assignment, and Assignor shall remove of
         Assignor's personal property from the Leaseback Premises. Assignor and
         Assignee further agree that the fixtures identified in Exhibit D to
         this Assignment shall remain the property of Assignor and may be
         removed from the Demised Premises by Assignor even though said fixtures
         are attached to the building in which the Demised Premises are located.

b.       Assignor represents to Assignee that, as of the date of this
         Assignment, Assignor has no knowledge of any violations of any law,
         governmental ordinance or code, including the Americans With
         Disabilities Act, applicable to the Demised Premises as currently used
         by Assignor and/or Sublessee. Assignee acknowledges that, in the event
         Assignee remodels or reconstructs the second level of the Demised
         Premises, the installation of an elevator may be required at Assignee's
         expense. With the exception of the foregoing representation, Assignee
         agrees it is leasing and accepts the Demised Premises "as is", "where
         is" and with all faults. Without limiting the generality of the
         foregoing, Assignor shall have no obligation to make, supply or perform
         any alteration, services, material, fixtures, equipment or decorations
         to the 

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         Demised Premises nor shall Assignor have any obligations regarding
         compliance of the Demised Premises and Assignee's use thereof with the
         Americans With Disabilities Act. In entering into this Assignment,
         Assignee has relied solely on its own investigation, examinations and
         inspections of the Demised Premises, and Assignee acknowledges Assignor
         has afforded Assignee the opportunity for a full and complete
         investigation, examination and inspection of the Demised Premises.

c.       Assignor agrees Assignee shall be entitled to take possession of the
         Demised Premises, other than the Subleased Premises and the Leaseback
         Premises, prior to the Effective Date at such time as written consent
         of the Landlord to this Assignment has been obtained in accordance with
         the provisions of Paragraph 6 hereof, subject to the following
         conditions:

         i)       Assignee shall not be obligated to pay Base Rent, Operating
                  Expenses or Real Estate Taxes prior to the Effective Date, but
                  Assignee shall pay for all utility services provided to that
                  portion of the Demised Premises occupied by Assignee; and

         ii)      Prior to occupying the Demised Premises, Assignee shall
                  provide Assignor with Certificates of Insurance complying with
                  the requirements of the Lease and this Assignment.

d.       Assignee acknowledges it is required by the terms of the Lease to
         obtain the Landlord's approval prior to performing any modifications or
         improvements to the Demised Premises. In the event Assignee undertakes
         any tenant improvement or construction work prior to the end of the
         term of the Leaseback Agreement, Assignee agrees to perform such work
         in a manner that will not unreasonably interfere with the conduct of
         Assignor's business within the Leaseback Premises.

         5. RECONCILIATION OF REAL ESTATE TAXES AND OPERATING EXPENSES. Assignor
and Assignee agree Assignor shall only be responsible for the actual "Real
Estate Taxes" (as defined in the Lease) and "Operating Expenses" (as defined in
the Lease) payable with respect to the Demised Premises, excluding the Subleased
Premises, prior to the Effective Date, and payable with respect to the Leaseback
Premises during the term of the Leaseback Agreement as provided in Paragraph 3
of this Assignment. Assigne shall look only to Sublessee for the payment of any
Real Estate Taxes or Operating Expenses payable with respect to the Subleased
Premises, and Assignor shall have no liability to Assignee for the Real Estate
Taxes and Operating Expenses payable with respect to the Subleased Premises. At
the time of reconciliation of the actual Real Estate Taxes and Operating
Expenses for the calendar year 1998, as required by the last paragraph of
Article 3 of the Lease, Assignor or Assignee, as the case may be, shall
reimburse the other party for any overpayment or underpayment by Assignor of
Real Estate Taxes or Operating Expenses payable with respect to the Demised
Premises or the Leaseback Premises during the calendar year 1998. Assignee
agrees to provide Assignor with copies of all documents received by Assignor or
available 

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to Assignor relating to the reconciliation of the actual Real Estate Taxes and
Operating Expenses for the calendar year 1998.

         6. CONSENT OF LANDLORD.

         a.       It shall be a condition of the continued validity of this
                  Assignment that the Landlord shall give its written consent to
                  this Assignment in accordance with the provisions of the
                  Lease. Assignee shall not be entitled to take possession of
                  the Demised Premises or assume Assignor's interest under the
                  Sublease unless and until the Landlord has consented to this
                  Assignment.

         b.       Assignor shall not be obligated to take any action or to incur
                  any cost or liability in order to obtain the consent of the
                  Landlord to this Assignment, other than to request such
                  consent from the Landlord and proceed with reasonable
                  diligence to secure such consent in accordance with the terms
                  of the Lease.

         c.       Assignee agrees that it shall fully cooperate with Assignor in
                  obtaining the consent of the Landlord to this Assignment, and
                  agrees that it shall execute and deliver any document or
                  agreement and provide all information that the Landlord shall
                  reasonably require, promptly following Assignor' or the
                  Landlord's request. Assignor and Assignee acknowledge that
                  they intend to request that the Landlord release Apertus from
                  all liability under the Lease from and after the Effective
                  Date, and Assignee agrees to request such release and
                  cooperate with Assignor in obtaining the Landlord's agreement
                  to release Assignor from liability from and after the
                  Effective Date. However, any consent by Landlord to this
                  Assignment shall not be deemed to release Apertus from
                  liability under the Lease unless such consent, by its terms,
                  expressly releases Apertus from such liability.

         d.       If for any reason whatsoever, the Landlord shall fail or
                  refuse to give its consent to this Assignment on or before the
                  Effective Date then, at any time after the Effective Date and
                  prior to such time as the Landlord's consent shall be given
                  and the parties shall be notified that the consent has been
                  given, either of the parties may cancel this Assignment by
                  giving written notice to the other whereupon this Assignment
                  shall be null and void and shall have no further force or
                  effect.

         7. INSURANCE. From and after the Effective Date, Assignee shall
maintain insurance coverage complying with the requirements of the Lease,
provided, however, that until the termination of the Leaseback Agreement and
Assignor's obligations under Paragraph 3 of this Assignment, Assignor shall
maintain insurance covering Assignor's continued use and occupancy of the
Leaseback Premises complying with the requirements of the Lease. On or before
the Effective Date, Assignor and Assignee shall each furnish the other party
with a Certificate of Insurance evidencing that Assignor and Assignee are
maintaining the insurance coverages required by this Assignment and the Lease.

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         8. CHANGES. This Assignment cannot be changed or amended in any manner
other than by a written agreement executed by Assignor and Assignee.

         9. SUCCESSORS AND ASSIGNS. Except as may be otherwise specifically
provided in this Assignment, the provisions hereof shall extend to, bind and
inure to the benefit of the parties hereto and their respective successors and
assigns.

         10. BROKERAGE. Assignor and Assignee represent to one another that they
have not dealt with any broker or agent in connection with this Assignment, nor
do they have any knowledge of any broker who has been involved or who has
claimed to be involved or instrumental in bringing about this Assignment, other
than Welsh Companies and William Ritter ("Assignor's Brokers") and Jerry Portnoy
("Assignee's Broker"). Assignee shall indemnify, defend and hold Assignor
harmless from and against all losses, damages, costs and liabilities (including,
without limitation, reasonable attorneys' fees) arising in connection with
claims made by any broker, agent or other person, other than Assignor's Brokers
and Assignee's Broker, for a brokerage commission, finder's fees or similar
compensation, by reason of or in connection with this Assignment, if such other
broker or other person claims to have dealt with Assignee. The broker's
commission payable to Assignor's Brokers shall be payable by Assignor in
accordance with a separate agreement between Assignor and Assignor's Brokers and
the broker's commission payable to Assignor's Brokers shall be divided between
Assignor's Brokers and Assignee's Broker in accordance with their separate
agreement.

         11. NOTICES. All notices, requests, approvals, waivers, consents,
deliveries or other communications that either party is required or desires to
send to the other in connection with this Assignment shall be in writing,
executed by the party sending the notice, and sent by registered or certified
mail, return receipt requested, with postage prepaid, or by a
nationally-recognized overnight courier service which provides a written return
receipt, addressed as follows: (a) if to Assignee, to its address at 7075 Flying
Cloud Drive, Eden Prairie, Minnesota 55344, Attention: James Istis; and (b) if
to Assignor, to its address at:7275 Flying Cloud Drive, Eden Prairie, Minnesota
55344, Attention: Steve Thimjon. Except in any instance where it may be
otherwise specifically provided in this Assignment, notice shall be deemed given
on the date which is two (2) business days after such notice is deposited with
the United States Postal Service

         12. INTERPRETATION, MISCELLANEOUS PROVISIONS.

         a.       This Assignment shall be governed by and construed in
                  accordance with the law of the State of Minnesota.

         b.       If any provision of this Assignment or the application thereof
                  to any person or circumstances shall, for any reason or to any
                  extent, be invalid or unenforceable, the remainder of this
                  Assignment and the application of that provision to other
                  persons or circumstances shall not be affected but rather
                  shall be enforced to the extent permitted by law.

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         c.       The captions, headings and titles contained in this Assignment
                  are solely for convenience of reference and shall not affect
                  its interpretation.

         d.       This Assignment shall be construed without regard to any
                  presumption or other rule requiring construction against the
                  party causing this Assignment to be drafted.

         e.       All of the terms, conditions, covenants, liabilities and
                  obligations of Assignor and Assignee under this Assignment
                  shall survive and be enforceable after the Effective Date.

         13. COMPLETE AGREEMENT. There are no representations, agreements,
arrangements or understandings, oral or written, between the parties relating to
the subject matter of this Assignment which are not fully expressed in this
Assignment.

         14. ATTORNEYS' FEES. The parties hereby agree that the prevailing party
in any action or legal proceeding commenced by either party arising out of or
concerning this Assignment shall be entitled to recover from the other party, in
addition to all other relief at law or in equity, reasonable attorneys' fees and
disbursements as fixed by a Court.

         IN WITNESS WHEREOF, Assignor and Assignee have executed and delivered
this Assignment effective as of the date stated in the first paragraph of this
Assignment.

                                       APERTUS TECHNOLOGIES INCORPORATED


Date:   April 16, 1998                 By  /s/ Steven Thimjon
                                       -------------------------------
                                       Its  Vice President and CFO



                                       BEST BUY CO., INC.


Date:   April 15, 1998                 By  /s/ Allen Lenzmeier
                                       --------------------

                                       Its  Executive Vice President

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