<PAGE>


                                                                  Exhibit 10.7

                                        CONFIDENTIAL TREATMENT REQUESTED
                                        UNDER 17 C.F.R. SECTIONS 200.80(B)(4),
                                        200.83 AND 230.406


                               SUB-LEASE AGREEMENT
              CLOVERLEAF COLD STORAGE CO. - THE TITAN CORPORATION


     THIS SUB-LEASE AGREEMENT is entered into effective as of September 1,
1999, by and between CLOVERLEAF COLD STORAGE Co., an Iowa corporation
("Landlord"), whose address for the purpose of this Sub-Lease Agreement is
2800 Cloverleaf Court, Sioux City, Iowa 51111, and THE TITAN CORPORATION, a
Delaware corporation ("Tenant"), whose address for the purpose of this
Sub-Lease Agreement is 3033 Science Park Road, San Diego, California 92121.

     IN CONSIDERATION of the mutual covenants contained in this agreement,
the parties agree as follows:

1.   LOCATION AND PREMISES.

     A.   Demised Premises. Landlord, for and in consideration of the
covenants and agreements herein contained, does demise and sub-lease to
Tenant, and Tenant hereby hires and sub-lets from Landlord, the following
described premises, which shall form a part of and be situated in that
certain warehouse building (the "Warehouse Premises") and located at 2640
Murray Street, Sioux City, Iowa (the "Demised Premises"). Said Demised
Premises shall consist of approximately 19,400 square feet as outlined on the
floor plan which is attached hereto as Exhibit "A", and incorporated herein
by reference.

     Any measurements to determine leased square footage are from the outside
walls and to the center of the interior walls. The approximate boundaries and
location of the Demised Premises are outlined on the floor plan of the
Warehouse Premises, which is marked as Exhibit "A". Landlord shall provide
sufficient automobile parking stalls for Tenant's employees, which parking
stalls shall be reasonably near the Demised Premises. Landlord shall have the
responsibility for maintenance and repair of the parking lot.

     B.   Areas Not Demised/Excluded Areas. It is hereby acknowledged and
agreed between the parties that the Demised Premises will only make up a
portion of the Warehouse Premises as aforementioned. That as aforesaid, the
Demised Premises shall consist of only that area which is outlined in Exhibit
"A".

2.   TERM. The term of this Sub-Lease shall be for five (5) years, commencing
on the Commencement Date and shall expire at midnight on the 5th anniversary
of the Commencement Date unless sooner terminated as herein provided.

     A.   COMMENCEMENT DATE. The parties agree that the Commencement Date
shall be February 1, 2000. The Commencement Date shall constitute the
commencement of the term of this Sub-Lease for all purposes, whether or not
Tenant has actually taken possession. If Tenant takes possession of the
Demised Premises prior to the Commencement Date, Tenant shall pay, in
advance, additional rental, pro-rated on a per diem basis. Tenant's entry
into the Demised

<PAGE>

Premises to perform Tenant's work on installing its equipment shall not be
deemed to constitute taking possession, if such entry occurs before the
Completion Date.

     B.   OPTION TO EXTEND TERM OF SUB-LEASE. If this Sub-Lease shall be in
force and effect on the date of the expiration of the term as set forth
herein, and Tenant on such date shall have fully performed all of its
obligations hereunder, and if Tenant is not in default under any terms of
this Sub-Lease, Tenant shall have the option to extend the term of this
Sub-Lease for one (1) additional term of five (5) years. Tenant must provide
Landlord with written notice of its intent to exercise this option at least
180 days prior to the expiration of its then current term. If said option is
exercised, the basic rental rates and additional rental rates for the first
year of the 5-year option term shall be the same rates as the prior year,
except as increased by the Consumer Price Index provisions of paragraph 4 of
this Sub-Lease, and all subsequent years of the option term shall be subject
to the increases pursuant to that paragraph 4. All other provisions of the
Sub-Lease as amended herein shall remain in full force and effect during the
term of the option.

3.   USE. Said Demised Premises are to be used for food processing, including
irradiation, offices, dock and related activities and for no other purpose
without prior written consent of Landlord, and any violation of this covenant
shall result in termination of this Sub-Lease upon ten (10) days written
notice to Tenant at the option of Landlord. Landlord leases the Warehouse
Premises from K-F Real Estate Co. Landlord covenants that upon Tenant paying
the rental and performing and observing all other obligations under the
Sub-Lease, Tenant may peaceably and quietly have, hold and enjoy the Demised
Premises for the term of the Sub-Lease, subject and subordinate to all
provisions of the Sub-Lease.

4.   RENTAL.

     A.   BASIC RENTAL. Tenant shall pay annual Basic Rental at the rates
provided below in equal monthly installments, in advance, with the first
installment due on the Commencement Date, and subsequent installments due on
the first day of each and every month thereafter, at the corporate mailing
address of Landlord, 2800 Cloverleaf Court, Sioux City, IA 51111 or at such
other places as Landlord may designate in writing. Said basic rental is
subject to increase based upon the fluctuation of the Consumer Price Index as
set forth hereinafter.

     Such annual Basic Rental shall be fixed for the first year of the
Sub-Lease term, but shall be adjusted annually thereafter for the remainder
of the Sublease term. Said adjustment for the first year shall be effective
beginning on the first anniversary of the Commencement Date, with an
adjustment for each succeeding year of the Sub-Lease term being made on each
succeeding anniversary of the Commencement Date. The adjustments shall
reflect and compensate Landlord annually for decreases in the purchasing
power of money, if any, as measured by the current Consumer Price Index as
more specifically described below. In no event will the rental be less than
that of the preceding year. A detailed formula of the annual adjustment of
rent as aforesaid is specifically set out hereinafter:

                                       2
<PAGE>

"BASIC RENTAL" for the leased square footage shall be the sum of the annual
square foot rental rates indicated below multiplied by the leased square
footage for each type of space, for the entire Demised Premises.


<TABLE>
<CAPTION>

     Type of Space                    Square Footage        Annual Rate
<S>                                   <C>                  <C>
     Office                            4,839 sq. ft.       $10.50 sq./ft.
     Rest of Demised Premises         14,560 sq. ft.       $17.50 sq./ft.
                                      --------------
     Total Square Footage             19,399 sq. ft.

</TABLE>



The initial Base Rental shall be $25,467.00 per month ($305,610.00 per year).


"BASE INDEX" shall mean the October 1998 level of the "Consumer Price Index
- Urban Wage Earners & Clerical Workers (CPI-W) - All Items - U.S. City
Average (1982-84 = 100)", as published by the Bureau of Labor Statistics,
U.S. Department of Labor.

"CURRENT INDEX" shall mean the level of the same index published for the
month of October of each year prior to the commencement of each applicable
annual adjustment term.

"ADJUSTED RENTAL" shall be the adjusted annual square foot Basic Rental
produced by multiplying the BASIC RENTAL by the ratio of the CURRENT INDEX to
the BASE INDEX, i.e.:

ADJUSTED RENTAL = BASIC RENTAL x (CURRENT INDEX/BASE INDEX)

     B.   EARLY VACATE. If the food pasteurization market does not
materialize as expected and Tenant removes its equipment from the Demised
Premises before the end of the Sub-Lease term, Landlord will use its best
efforts to find a replacement tenant on the same or better (in Landlord's
sole judgement) rental and terms and, once such a replacement is found, will
release Tenant from its obligation to pay Basic Rental. Notwithstanding the
above, if Tenant vacates the premises prior to the end of the Sub-Lease term,
Landlord will reduce the Basic Rental (but only the Basic Rental) in the
fifth year to 60% of the rent otherwise specified in the Sub-Lease. Any other
amounts payable under this Sub-Lease shall not be reduced.

     C.   SPECIAL BUILDOUT RENTAL: In addition to Basic Rental, Tenant shall
pay to Landlord Special Buildout Rental.


          1.  PRODUCTION ROOM. Special Buildout Rental for the production
room shall be a monthly amount equal to 2.15% of an amount equal to the total
costs incurred by Landlord for the construction of the containment room and
other buildout within the main production room (including but not limited to
the maintenance office, control room, dosimetry lab, etc.). Such amount may
be increased as provided in the following paragraph. Landlord shall cooperate
with Tenant in attempting to keep the Special Buildout costs as low as
possible, keeping in mind that such costs are dictated by designs and plans
provided by Tenant. Special Buildout Rental shall be payable on the
Commencement Date and the first of each month thereafter during the initial
Sub-Lease term. However, notwithstanding anything to the contrary


                                       3



<PAGE>

in this agreement, if Tenant vacates the premises prior to the end of the
Sub-Lease term, the Special Buildout Rental for the remaining months of the
Sub-Lease term shall become immediately due and payable.


          2.  OFFICE. Special Buildout Rental for the office shall be a
monthly amount equal to 2.15% of the amount by which the total costs incurred
by Landlord for the construction of the office and interior buildout to
Tenant's specifications (including, but not limited to, telephone, data and
alarm cabling) exceeds $54 per square foot (or $261,306). Special Buildout
Rental for the office shall be payable on the Commencement Date and the first
of each month thereafter during the initial Sub-Lease term. However,
notwithstanding anything to the contrary in this agreement, if Tenant vacates
the premises prior to the end of the Sub-Lease term, the Special Buildout
Rental for the office for the remaining months of the Sub-Lease term shall
become immediately due and payable.


          3.  AUDIT. Tenant shall have the right to audit the construction
figures on which Special Buildout Rental is computed for 30 days following
the submission by Landlord of the Special Buildout Rental amounts to Tenant.

     D.   RESTORATION & OTHER AMOUNTS. In addition to Basic Rental and
Special Buildout Rental, Tenant shall pay to Landlord the amounts provided in
Section 29 and all other amounts provided for under the other terms of this
Sub-Lease. All amounts payable under this Sub-Lease shall be deemed rent for
all purposes, including default and collection.


     E.   Any rental or other payments not paid within 20 days of the due
date as stated herein shall bear interest of 12% per annum.


5.   CONSTRUCTION OF IMPROVEMENTS & INSTALLATION OF EQUIPMENT:

     A.   LANDLORD IMPROVEMENTS. Landlord shall construct its improvements
(the "Landlord's Improvements") to the Demised Premises in accordance with
the plans and specifications provided in advance by Tenant and approved in
writing by Landlord. This will include concrete floor, exterior walls,
(including demising wall), exterior windows and doors, loading docks with
lights and levelers, finished office space outside the production room, main
production room with additional buildout, including the containment room,
etc., refrigeration piping from the main refrigeration engine room outside
the Demised Premises, refrigeration fans and coils, heating and
air-conditioning system for the office and production room, electrical power
brought to a 1200 amp panel per Tenant's approved plan (no distribution) and
electrical J-boxes at the outside fascia of building for Tenant's sign. All
roof penetrations shall be coordinated by Landlord's contractor so as not to
void any roofing warranties. Landlord shall not be responsible for the
installation of Tenant's equipment and fixtures, including the special E-beam
equipment and the electrical wiring therefor.

     B.   COMPLETION DATE. "Completion date" shall be the date on which the
Landlord's Improvements shall have been completed in accordance with the
plans and specifications and the Tenant's space shall be ready as provided in
Paragraph 5.A. Landlord shall

                                       4



<PAGE>

use its best efforts to establish the completion date as the date set forth
in section 2. In the event that the Landlord's Improvements have not in fact
been completed, as of that date, Tenant shall notify Landlord in writing of
its objections. Landlord shall have a reasonable time after delivery of the
notice in which to take such corrective actions as may be necessary and shall
notify Tenant in writing as soon as it deems such corrective action has been
completed and the Landlord's Improvements are ready for occupancy. Upon
completion of construction of the Landlord's Improvements, Tenant shall
deliver to Landlord a letter accepting the Demised Premises as suitable for
the purposes for which they are let. Whether or not Tenant has executed such
letter of acceptance, taking possession of the Demised Premises by Tenant
shall be deemed to establish conclusively that the Landlord's Improvements
have been completed in accordance with the plans and specifications, are
suitable for the purposes for which the Demised Premises are let, and that
the Demised Premises are in good and satisfactory condition as of the date
possession was so taken by Tenant.

     C.   TENANT'S WORK. Landlord shall cooperate with Tenant so that Tenant
may enter the Demised Premises as soon as possible, consistent with safety
considerations, to begin Tenant's work, even before the Completion Date.
Tenant shall be allowed to install the Tenant's equipment and fixtures,
including the special E-beam equipment and the electrical wiring therefor,
needed by Tenant in the Demised Premises but subject to the sole and
exclusive approval of Landlord prior to any such installation. Tenant shall
contract directly with Tenant's own contractors for such installation. Tenant
shall be responsible for paying the contractors for such installation based
on Tenant's agreement with the contractors.

6.   MAINTENANCE AND REPAIRS. Except as otherwise provided herein, Landlord
at its own cost and expense shall maintain and keep in good repair all
portions of the Warehouse Premises (specifically excluding the Demised
Premises) and the grounds, including, without limitation, the roof and the
exterior walls of the building, roadways, railways and sidewalks surrounding
such building, and including all mechanical equipment and fixtures such as
sprinkler systems, windows, doors, floors, heating, plumbing,
air-conditioning equipment, refrigeration equipment (including such equipment
within the Demised Premises), sewer system and electrical wiring. Landlord
shall provide reasonable services for snow removal from Tenant's access road
and parking area.

     Tenant, at its own cost and expense, shall maintain and keep in good
repair all portions of the Demised Premises and shall preserve same free from
obnoxious odors, vermin, rubbish, debris or any other foreign matter, keep it
in a clean and sanitary manner, and shall make all repairs to the Demised
Premises necessary to maintain the Demised Premises in its condition at the
Commencement Date, reasonable wear and tear excepted. Tenant shall also at
its own cost and expense maintain and keep in good repair any and all
mechanical equipment and fixtures furnished or installed by it for the
Demised Premises and shall be responsible for the maintenance and repair of
all electrical wiring and electrical equipment for all of Tenant's equipment
installed by Tenant in the Demised Premises. Tenant agrees to keep faucets
closed so as to prevent waste of water and flooding of premises and to
promptly take care of any leakage or stoppage in any of the water, gas or
waste pipes. The Tenant agrees to maintain adequate heat to

                                       5

<PAGE>

prevent freezing of pipes. Tenant shall provide snow removal from sidewalks and
pedestrian entrances.

         In addition to all other amounts paid by Tenant to Landlord hereunder,
Tenant shall pay in advance to Landlord the total of $[...***...] which amount
shall serve as a maintenance reserve for the Demised Premises for Tenant's
maintenance expense incurred in maintaining the Demised Premises. During the
term of this Sub-Lease, said maintenance reserve may be used by Landlord for
repair and maintenance expenses incurred in repairing and maintaining the
existing Demised Premises excluding the payment for tenant improvements or
additions and alterations of the Demised Premises.


         From time to time, Tenant may submit requests to Landlord to pay for
said reasonable repairs and maintenance from said maintenance reserve. Said
request shall be approved by Landlord within 15 days of said request unless
said expenditure is not for the repair and maintenance of the existing
Demised Premises. Upon approval of said request, Tenant shall contract to
make said repairs only with contractors approved by Landlord or Tenant's
employees, if approved by Landlord. Landlord may from time to time require
Tenant to make all repairs necessary to maintain the Demised Premises in its
condition on the Commencement Date, reasonable wear and tear excepted. In the
event Tenant does not commence said repairs within 30 days from Landlord's
request, then Landlord shall have the unconditional right to make said
repairs and deduct the total cost of the same from said maintenance reserve
and bill Tenant for the cost of said repairs in excess of said maintenance
reserve. Any bills submitted by Landlord and not paid within 15 days from the
date of invoice shall bear interest at 16% per annum.


         Tenant shall be liable for the payment of all said repair and
maintenance expense for the Demised Premises in excess of the maintenance
reserve, however, at the end of this Sub-Lease term, any remaining balance in
the maintenance reserve after the Demised Premises have been returned to
Landlord in its condition on the Commencement Date shall be paid by Landlord to
Tenant. Tenant shall surrender the Demised Premises in as good condition as same
were at the Commencement Date, reasonable wear and tear only excepted.

         If such maintenance reserve shall for any reason or at any time fall
below or be less than $[...***...], then Tenant shall have 30 days after
Landlord invoices Tenant for such deficiency in which to pay Landlord for
deposit into such maintenance reserve an amount so as to keep the maintenance
reserve at $[...***...] at all times. If Tenant does not pay such amounts to
Landlord for deposit within the 30 days as aforementioned, Landlord shall
have the option to terminate this Sub-Lease upon 30 days written notice to
Tenant.

7.       LAWS AND ORDINANCES. Tenant shall fully comply with and obey all laws,
ordinances, reasonable rules, regulations and requirements of all regularly
constituted authorities, and such reasonable rules and regulations of Landlord
as posted in said Warehouse Premises by Landlord, in any way affecting Tenant's
occupancy, said Warehouse Premises, or the use thereof, or this Sub-Lease, so
long as such do not materially adversely effect this Sub-Lease. Tenant shall not
use or permit as determined by Landlord the use of said Demised Premises for any
hazardous or illegal purposes.


                                       6

                      *Confidential Treatment Requested
<PAGE>

8.       UTILITIES. Except as otherwise specifically provided, Tenant shall be
solely responsible for and promptly pay all rates and charges for all utilities
or services for the Demised Premises, including, without limitation, such rates
and charges for gas, electricity, water, sewer, light, heat and power used or
supplied upon or in connection with the Demised Premises, and further including
the cost of installation of the meters or submeters and associated charges.

         A.       The parties specifically agree that wherever possible,
utilities to the Demised Premises shall be separately metered or submetered and
that the cost of the installation of such meters shall be at the sole expense of
Tenant. Pursuant to such metering, Tenant shall pay directly to the applicable
utility company the cost of such utilities actually used by Tenant. In no event
shall Landlord be liable for an interruption or failure in the supply of any
such utilities or services to the Demised Premises.

         B.       Landlord shall pay the utility expenses for refrigeration
supplied to the Demised Premises by the central engine room located outside the
demised Premises for normal meat processing operations; however, refrigeration
required by Tenant's unique operational requirements, including additional
chilling for Tenant's equipment and special ventilation needs shall be billed to
Tenant at Landlord's normal charges per unit. Landlord will use its best efforts
to set forth the billing formula therefor on Exhibit "B" attached.

9.       CHANGES IN DEMISED PREMISES. Tenant shall make no additions, alteration
or structural changes in the Demised Premises, except as approved in advance in
writing by Landlord, which approval shall not be unreasonably withheld.

10.      ENTRY BY LANDLORD. Tenant shall permit Landlord and the agents of
Landlord to enter upon the Demised Premises at all reasonable times to examine
the condition thereof and conditions of Tenant's occupancy or to make such
repairs, additions or alterations therein as Landlord may deem necessary, or to
exhibit the same. Nothing herein shall be construed to allow Landlord or any
other person or entity access to or the right to review property of Tenant that
is of a confidential or proprietary nature. This shall include, without
limitation, Tenant's books and records, financial information, customer lists,
pricing information, information on Tenant's manufacturing and marketing
processes, personnel records, trade secrets and other information that would
normally be considered to be of a confidential or proprietary nature. Any such
information, if obtained by Tenant or anyone by, through or under Tenant, shall
remain the property of Tenant and shall remain confidential.

11.      REAL ESTATE TAXES. All real estate taxes and special assessments levied
and assessed by lawful authority against the Demised Premises shall be timely
paid by Landlord, except that any such taxes levied or assessed with respect to
special improvements and/or fixtures constructed or installed by or for Tenant,
including the additional buildout in the production room and Tenant's equipment,
shall be paid by Tenant.

12.      ADVERTISING SIGNS. Subject to Landlord's prior written approval, Tenant
shall have the right and privilege of erecting and maintaining (at Tenant's own
expense) such signs, electric


                                       7
<PAGE>

or otherwise, in or upon the Demised Premises as it may deem necessary or
advisable for the advertising of its business. Such signs shall not violate
any local rules, regulations or ordinances and shall be in keeping with the
aesthetic climate of the locale as determined by Landlord. Tenant shall
repair any and all damages caused by the erection, maintenance, or removal of
any such sign or signs by Tenant. Tenant agrees to indemnify and save
Landlord harmless from any and all damages or claims for damages caused by or
growing out of the erection, maintenance, existence, or removal of any such
sign or signs maintained by Tenant in or upon the Demised Premises. Landlord
reserves the right to erect and maintain such sign or signs as it deems
necessary in the conduct of its business.

         Landlord, during the last 90 days of this Sub-Lease or extension, shall
have the right to maintain in the windows or on the Warehouse Premises or on the
Demised Premises either or both a "For Rent" or "For Sale" sign, and Tenant will
permit, at such time, prospective lessees or buyers to enter and examine the
Demised Premises. Nothing herein shall be construed to allow Landlord or any
other person or entity access to or the right to review property of Tenant that
is of a confidential or proprietary nature. This shall include, without
limitation, Tenant's books and records, financial information, customer lists,
pricing information, information on Tenant's manufacturing and marketing
processes, personnel records, trade secrets and other information that would
normally be considered to be of a confidential or proprietary nature. Any such
information, if obtained by Tenant or anyone by, through or under Tenant, shall
remain the property of Tenant and shall remain confidential.

13.      DISCLAIMER OF LIABILITY. Landlord and Landlord's affiliated
corporations and partnerships or other entities related by common ownership, and
their directors, officers, shareholders, employees, representatives and agents,
shall not be liable for any loss or damage occasioned by the acts or negligence
of any owners or occupants or adjacent or contiguous property (not including
Landlord if Landlord happens to be an owner or an occupant) or their employees;
Tenant's fault or negligence; acts of God; acts or negligence of any person not
in the employ or under the authority of Landlord; the occupancy, use or failure
to maintain said premises by Tenant or breach of a covenant herein by Tenant.

Tenant and Tenant's affiliated corporations and other entities related by common
ownership, and their directors, officers, shareholders, employees,
representatives and agents, shall not be liable for any loss or damage
occasioned by the acts or negligence of any owners or occupants of adjacent or
contiguous property (not including Tenant if Tenant happens to be an owner or an
occupant) or their employees; Landlord's fault or negligence; acts of God; acts
or negligence of any person not in the employ or under the authority of Tenant;
or the failure to maintain the Warehouse Premises by Landlord or breach of a
covenant herein by Landlord.

14.      INDEMNIFICATION. Except as may be waived in paragraph 16 below,
Landlord and Tenant agree to indemnify each other, and their respective
affiliated corporations and partnerships or other entities related by common
ownership, and their respective directors, officers, shareholders, employees,
representatives and agents, against and to hold each other harmless from any and
all claims or demands of any third party arising from or based upon any alleged
act, omission, or negligence of the indemnifying party or its contractors,
concessionaires,


                                       8
<PAGE>

licensees, agents, servants, invitees, employees, or anyone else for whom the
indemnifying party may be or alleged to be responsible. In the event that
either party shall without fault on its part be made a party to any
litigation commenced by any third party against the other party, then such
other party shall protect and hold the party without fault harmless from and
with respect to such litigation, and shall pay all costs and expenses
incurred or paid by the party without fault in connection with such
litigation, together with any judgments rendered against the party without
fault.

15.  LIABILITY INSURANCE COVERAGE. Tenant hereby agrees that it will,
throughout the term of this Sub-Lease, and any extension thereof, at its own
cost and expense, maintain comprehensive general public liability insurance
covering the Demised Premises for protection of Landlord and its affiliated
corporations and partnerships and Tenant as their interests may appear, with
a limit of liability for property damage of not less than [...***...] Dollars
($[...***...]) and with a limit of liability for bodily injury to or death of
one person in an amount not less than [...***...] Dollars ($[...***...]) and,
subject to that limitation for every person injured and killed, a total
limitation for all claims arising out of one accident resulting in bodily
injury to or death of more than one person of not less than [...***...]
Dollars ($[...***...]). Tenant agrees that this insurance shall be in a form
and issued by a company or companies satisfactory to Landlord. Tenant shall
provide Landlord with a certificate or certificates evidencing such coverage,
that Landlord, Landlord's Lessor, K-F Real Estate Co., and Tenant are covered
by such policy or policies as their interests may appear as "named insureds",
and that such policy or policies are non-cancelable without 30 days advance
written notice to Landlord. Said written notice shall be made to Landlord at
the address set out herein for the giving of all notices and shall be made by
certified mail, return receipt requested.

16.  WAIVER OF SUBROGATION. Neither Landlord, and its affiliated or related
corporations or partnerships, nor Tenant shall be liable to the other for any
business interruption or any loss or damage to property or injury or death of
persons occurring on the Demised Premises or in any manner growing out of
Tenant's use of the Demised Premises, whether or not caused by the fault or
negligence of Landlord or Tenant, or their respective related or affiliated
corporations or partnerships, agents, employees, subtenants, licensees, or
assignees and regardless of the cause of such loss or damage. This release shall
apply only to the extent that such business interruption, loss or damage to
property, or injury or death of persons is covered by insurance, and to the
extent that recovery is made of proceeds thereunder, and regardless of whether
such insurance protects Landlord, Tenant or both. Nothing herein shall be
construed to impose any other or greater liability upon either of the parties to
this Sub-Lease than would have existed in the absence of this paragraph. The
parties shall provide one-another with written evidence that their respective
insurers are aware of this Sub-Lease and this paragraph, and that each is in
agreement that these provisions are not prohibited by the terms of the
applicable policies underwritten by them.

17.  ASSIGNMENT OR SUBLETTING. Tenant shall not assign, sublet or in any
manner transfer this Sub-Lease or any interest therein or part of same, and
will not suffer or remit any assignment or transfer thereof by operation of
law, except upon the prior written consent of Landlord, which consent shall
not be arbitrarily or capriciously withheld. The basis for withhold-

                                       9

                      * Confidential Treatment Requested

<PAGE>

ing of such consent include, but are not limited to: (a) an unsatisfactory
credit history and/or a showing of unsatisfactory financial responsibility of
the proposed transferee; (b) the business reputation of the proposed
transferee is not in accordance with generally accepted commercial standards;
(c) the use of the Demised Premises would not be identical to that required
by this Sub-Lease; (d) the proposed transferee's projected use of the Demised
Premises involves the use, storage, generation or disposal of any hazardous
material as defined by any federal or state laws, rules or regulations; (e)
the proposed use of the Demised Premises violates any other agreement
effecting the Demised Premises, Landlord or any other lessees in the
Warehouse Premises; and (f) the transfer and/or the intended use of the
Demised Premises by the proposed transferee would be contrary to public
policy or statute.

     If Landlord elects to consent to any such assignment, sublet or
transfer, and the same is at a higher rent than is provided by this
Sub-Lease, any such excess rent shall be paid to the Landlord. For the
purposes of this paragraph 17, the transfer of a majority of issued stock of
any corporate lessee, or the transfer of a majority of the total interest of
any partnership lessee, however accomplished, shall be deemed an assignment
of this Sub-Lease. Assignment shall not relieve Tenant of any of its
obligations or liabilities hereunder for the Sub-Lease term; both Tenant and
any and all subsequent assignees shall thereafter be deemed to be bound
hereunder. It is agreed that an attempted assignment or subletting without
Landlord's prior written consent shall constitute a material breach of this
Sub-Lease.

18.  TERMINATION AND DEFAULT. Tenant shall surrender and deliver up the
Demised Premises at the end of the Sub-Lease term, or any extensions thereto,
in as good order and condition as at the Commencement Date or may be put by
Landlord, reasonable use and natural wear and tear or unavoidable casualty
excepted. Tenant shall at such time, upon Landlord's request, remove at its
own expense any internal or external walls, partitions, signs, fixtures,
improvements or other items placed in or on or installed or constructed in
the Demised Premises by Tenant or installed by Landlord at Tenant's request
or expense.

     If Tenant shall fail to pay when due any installment of any rental or
other sums of money payable to Landlord (time being of the essence and no
notice of default being required) or in the event Tenant shall breach or fail
to comply with any other provision, covenant, condition or undertaking of
this Sub-Lease on its part to be performed, and such default shall continue
without correction for a period of 10 days after written notice thereof is
given to Tenant by Landlord (time being of the essence), or if Tenant vacates
or abandons the Demised Premises, or if Tenant fails to continuously occupy
and operate the Demised Premises as herein required, or if Tenant is adjudged
bankrupt or insolvent or makes an assignment for the benefit of creditors,
defaults under Tenant financing, or if a receiver is appointed to take charge
of Tenant's business, or if any execution or attachment is issued against
Tenant whereupon the Demised Premises or any fixtures thereon are taken or
attempted to be taken and the same is not released within 10 days after
demand from Landlord, then Landlord will be entitled, at Landlord's sole
option (time being of the essence of all such conditions) to enter and take
immediate and exclusive possession of the Demised Premises and all fixtures
therein, with or without force of legal process, and without notice or
demand, and to expel Tenant and all persons claiming through or under Tenant.
In case of such default by Tenant, Landlord shall also have the option to
terminate and cancel

                                       10

<PAGE>

this Sub-Lease effective upon written notice to Tenant, whereupon any and all
covenants, conditions and obligations of Landlord under this Sub-Lease will
cease and terminate.

     Tenant agrees that notwithstanding the occurrence of any such event
giving Landlord the right of re-entry as aforesaid, and whether or not
Landlord has re-entered the Demised Premises or gained possession thereof,
and whether or not Landlord has relet the Demised Premises in whole or in
part, Landlord will not be deemed to have accepted the surrender of the
Demised Premises or of this Sub-Lease and Tenant will immediately pay to
Landlord in one lump sum all rents reserved to Landlord for the entire
remaining Sub-Lease term and Tenant will also remain liable for the
performance of all other covenants, conditions or undertakings of Tenant and
the payment of all other sums during the full period which otherwise would
have constituted the term of the Sub-Lease, including damages for failure to
perform any of the same or for any loss of rents or damages which Landlord
may then or thereafter suffer through the period of said entire term.
Landlord will have the right at any time after exercising any option given to
Landlord in this paragraph to exercise thereafter any other option hereunder
or such legal rights as Landlord would have in the absence of such options.
If Landlord does not elect to terminate and cancel this Sub-Lease on account
of Tenant's breach, Landlord agrees to use reasonable diligence to relet said
Demised Premises upon the best terms fairly obtainable at the time of such
reletting, consistent with the character of the Demised Premises, and the
obligation of Tenant for damages hereunder will be mitigated thereby to the
extent of the net rents when actually received from such reletting, after
deduction for all expenses of Landlord, including, without limitation,
expenses attributable to alterations and repairs Landlord deems advisable to
relet the Demised Premises and all reasonable attorneys' fees.

19.  HOLDOVER. Should Tenant, with or without the express consent of
Landlord, continue to hold or occupy the Demised Premises after the
expiration of the term of this Sub-Lease such holding over beyond the term,
it is agreed that the rental shall be [...***...] per cent ([...***...]%) of
the monthly rental amount in effect for the first month of holding over,
[...***...] per cent ([...***...]%) for the second month and [...***...] per
cent ([...***...]%) for the third and each following month and Tenant shall
pay such amount so established for such holding over and shall operate and be
construed as creating a tenancy at sufferance and nor for any other term
whatsoever, but the same may be terminated by Landlord by giving Tenant five
(5) days written notice thereof, and at any time thereafter Landlord may
physically re-enter and take possession of said Demised Premises, any rule in
law or equity to the contrary notwithstanding.

20.  ACCEPTANCE OF DEMISED PREMISES. Tenant accepts said Demised Premises in
the condition they may be at the commencement of the term hereof, "as is",
subject to all defects therein, whether concealed or otherwise, and whether
known or unknown to said Landlord, and releases and forever discharges said
Landlord from and Tenant accepts any and all damages of every kind and nature
that may be in any way occasioned thereby. At all times Tenant shall
indemnify and save said Landlord, said Demised Premises and the improvements
thereon harmless from all liens and all liability in any way arising out of
Tenant's use or condition of said Demised Premises or of the improvements
thereon.

                                       11

                      *Confidential Treatment Requested
<PAGE>

21.  DAMAGE TO OR DESTRUCTION OF DEMISED PREMISES. If during the term of the
Sub-Lease, or any extensions thereof, the aforesaid Warehouse Premises, or
any part thereof, shall be so damaged by fire or other casualty, unless
caused by Tenant's negligence, the elements or causes other than Tenant's
negligence as to render the Demised Premises partially unfit for use by
Tenant for the intended purpose of this Sub-Lease and shall be capable of
being repaired with a reasonable time, Landlord shall promptly undertake the
repair of same and during the term that the Warehouse Premises is
untenantable, Tenant's rent shall abate pro-rata to the extent of the portion
destroyed, assuming that the general processing business of Tenant can be
carried on in the remaining Demised Premises. If, during said term, or any
extensions thereof, the aforesaid Warehouse Premises, or any part thereof,
shall be destroyed or so damaged by fire, the elements or other causes (other
than Tenant's negligence) as to render the Demised Premises totally unfit for
use by Tenant for the intended purpose of this Sub-Lease, Tenant shall have
the option to terminate this Sub-Lease. Such option to terminate shall be
exercised by Tenant giving written notice to Landlord of its election to
terminate within 30 days after the Demised Premises is rendered totally unfit
for use by Tenant.

     Notwithstanding the foregoing provisions, in the event the Demised
Premises or any part thereof shall be damaged or destroyed as to render the
Demised Premises partially or totally unfit for use by Tenant for the
intended purposes of this Sub-Lease, and said destruction or damage is caused
or due to the fault or negligence of Tenant, or Tenant's servants, employees,
contractors, agents, visitors, or licensees, then, without prejudice to any
other rights and remedies of Landlord, the Sub-Lease shall not terminate, but
the following provisions shall apply. If the aforementioned destruction or
damage which is caused by or due to the fault or negligence of Tenant renders
the Demised Premises partially unfit for use by Tenant for the intended
purpose of this Sub-Lease, said Sub-Lease shall not terminate, and Landlord
shall promptly undertake to repair the same, but there shall be no
apportionment or abatement of any rent during that period of time. If the
aforesaid Warehouse Premises or any part thereof shall be destroyed or
damaged by fire due to or caused by Tenant's fault or negligence as to render
the Demised Premises totally unfit for use by Tenant for the intended purpose
of this Sub-Lease, the Sub-Lease shall not terminate, but Landlord shall have
the option of rebuilding the Warehouse Premises and of providing the same
amount in kind and space herein leased in the Warehouse Premises as rebuilt.
Such option to rebuild shall be exercised by Landlord giving written notice
to Tenant of its election to rebuild within 30 days after the Demised
Premises is rendered totally unfit for use by Tenant. In the event of the
exercise of this option, Landlord shall promptly undertake the reconstruction
of said Warehouse Premises, but there shall be no apportionment or abatement
of any rent due under this Sub-Lease. However, Tenant's obligation to pay
rent under this paragraph shall be reduced by any and all amounts of
insurance proceeds for loss of rents received by Landlord while said
Warehouse Premises is being repaired or rebuilt.

     In the event that the entire Warehouse Premises or any part thereof or
the land on which it is located or any part thereof should at any time be
condemned or otherwise taken by public authority, the entire award or damages
shall be paid to Landlord and Tenant as their interests may appear, and
Landlord may, at its option, terminate this Sub-Lease without liability to
Tenant for damage to the unexpired term of the leasehold. Landlord shall not
be liable for any interruptions to Tenant's use due to any act of God.

                                       12

<PAGE>

22.  NO WAIVER. No waiver, on the part of the respective parties hereto, or
their successors or assigns of any default or breach by either party of any
covenant, agreement or condition of this Sub-Lease shall be construed to be a
waiver of the rights of the party as to any prior or future default or breach
by the other party.

23.  REMEDIES CUMULATIVE. The remedies available to Landlord and Tenant under
the terms of this agreement and in law or equity shall be cumulative and the
exercise of one remedy shall not constitute an election of or waiver of
remedies.

24.  SUBORDINATION. This Sub-Lease shall be subject and subordinate at all
times to the lien of existing mortgages and deeds of trust which are a lien
on the Demised Premises. Either Landlord or Landlord's Lessor may assign its
rights under this Sub-Lease as security to the holders of one or more
mortgages (which term shall include a mortgage, deed of trust, or other
encumbrance) now or thereafter in force against all or any part of the land
or improvements constituting the Demised Premises or the Warehouse Premises.
Upon the request of Landlord or Landlord's Lessor, Tenant will subordinate
its rights hereunder to the lien of one or more mortgages (which term shall
include a mortgage, trust deed, or other encumbrance) now or hereafter in
force against all or any part of the land and improvements constituting the
Demised Premises or the Warehouse Premises, and to all advances made or
hereafter to be made upon the security thereof; provided, however, that in
the event of its acquiring title to the Demised Premises or the Warehouse
Premises, whether through foreclosure, judicial process or otherwise, the
mortgagee or holder of the mortgage shall recognize the validity of this
Sub-Lease and shall honor the rights of Tenant hereunder so long as Tenant:
(a) is not in default under this Sub-Lease at the time such mortgagee
acquires title to the Demised Premises or the Warehouse Premises, and (b)
agrees to attorn to such mortgagee as if it were the original Landlord
hereunder. In connection therewith, Tenant shall upon the request of
Landlord, or Landlord's Lessor or any mortgagee or holder of a mortgage on
the Demised Premises or Warehouse Premises, execute and deliver to such
requesting party an Estoppel Certificate as set forth in paragraph 46
hereinafter. Under no circumstances will Landlord or Landlord's Lessor
execute any deed of trust or security agreement with grants or attempts to
grant a security interest in any equipment, leasehold improvements or other
property of Tenant, and Tenant shall not be required to convey such security
interest to any lender or creditor of Landlord or Landlord's Lessor.

                                       13
<PAGE>

25.  NOTICES. Any notice required to be given hereunder shall be in writing
and shall be deemed to have been served and given when mailed by registered
or certified United States mail, return receipt requested. If such notice is
to Landlord, it shall be sent to:

                   Cloverleaf Cold Storage Co.
                   2800 Cloverleaf Court
                   Sioux City, IA 51111
                   Attention: Daniel Kaplan

      copy to:     Kent Vriezelaar
                   421 Nebraska St., P.0. Box 1557
                   Sioux City, IA 51102

      If such notice is to Tenant, it shall be sent to:

                   THE TITAN CORPORATION
                   3033 Science Park Road
                   San Diego, CA 92121
                   Attention: L.L. "Mike" Fowler, Corporate Vice President

26.  NO MECHANICS LIENS. Neither the Tenant nor anyone claiming by, through,
or under the Tenant shall have the right to file or place any mechanics lien
or other lien of any kind or character whatsoever, upon the Demised Premises
or the Warehouse Premises, or upon any building or improvement thereon, or
upon the leasehold interest of the Tenant therein, and notice is hereby given
that no contractor, sub-contractor, or any other who furnishes any material,
service or labor for any building, improvements, alterations, repairs or any
part thereof, shall at any time be or become entitled to any lien thereon,
and for the further security of the Landlord and Landlord's Lessor, the
Tenant covenants and agrees to give actual notice thereof in advance, to any
and all contractors and subcontractors who may furnish or agree to furnish
any such material, service or labor.

     Tenant shall do all things necessary to prevent the filing of any
mechanic's or other liens against the Demised Premises or the Warehouse
Premises, or the interest of any mortgagees or holders of any deed of trust
covering the Demised Premises or the Warehouse Premises, by reason of any
work, labor, services performed or any materials supplied or claimed to have
been performed or supplied to Tenant, or anyone holding the Demised Premises,
or any part thereof, through or under Tenant. If any such lien shall at any
time be filed, Tenant shall cause the same to be vacated and canceled of
record within 30 days after the date of the filing thereof. If Tenant shall
fail to vacate or release such lien in the manner and within the time period
aforesaid, then, in addition to any other right or remedy of Landlord
resulting from Tenant's said default, Landlord may, but shall not be
obligated to, vacate or release the same either by paying the amount claimed
to be due or by procuring the release of such lien by giving security, or in
such other manner as may be prescribed by law. Tenant shall repay to
Landlord, on demand, all sums disbursed or deposited by Landlord pursuant to
the foregoing provisions of this paragraph,

                                       14

<PAGE>

including Landlord's costs, expenses and reasonable attorneys' fees incurred
in connection therewith.

     However, nothing contained herein shall imply any consent or agreement
on the part of Landlord or Landlord's Lessor or any ground or underlying
lessors or mortgagees or holders of deeds of trust of the Warehouse Premises
or Demised Premises to subject their respective estates or interest to
liability under any mechanic's or other lien law, whether or not the
performance or the furnishing of such work, labor, services, or materials to
Tenant or anyone holding the Demised Premises, or any part thereof, through
or under Tenant, shall have been consented to by Landlord and/or any of such
parties.

27.  PERSONAL PROPERTY, FIXTURES AND MACHINERY OF TENANT. It is mutually
agreed that all personal property on the Demised Premises, including
merchandise of every kind, nature, and description, furnishings, equipment
and trade fixtures, owned or installed by Tenant (not including fixtures and
equipment owned and installed by Landlord), and all other property hereafter
placed or kept on the Demised Premises by Tenant, are and shall continue to
be the sole property of Tenant, unless the same shall have been installed to
replace equipment previously installed by Landlord. Tenant may, during the
term of this Sub-Lease or any extensions thereof, remove any furniture, trade
fixtures, or equipment as it may so desire, provided Tenant is not then in
default under this Sub-lease and Tenant shall repair all damages resulting
from such removal, and return the Demised Premises to its original condition,
reasonable wear and tear excepted, as nothing herein is intended to impose
any restrictions on the use of the furniture, trade fixtures, or equipment as
Tenant may deem necessary or desirable in the operation of its business.

     All personal property, including goods, wares, merchandise, trade
fixtures and other personal property of Tenant in the Demised Premises, shall
be at the risk of Tenant only. Landlord shall not be or become liable for any
damage to such personal property, to the Demised Premises or to Tenant or any
other persons or property as a result of water leakage, sewerage, electric
failure, gas odors or for any damage whatsoever done or occasioned by or from
any plumbing, gas, water or other pipes or any fixtures, equipment, wiring or
appurtenances whatsoever, or for any damage caused by water, snow or ice
being or coming upon the Demised Premises, or for any damage arising from any
act or neglect of other tenants, occupants or employees of the building in
which the Demised Premises are situated or arising by reason of the use of,
or any defect in, said building or any of the fixtures, plumbing, equipment,
wiring or appurtenances therein, or by the act of neglect to Landlord or any
other person or caused in any other manner whatsoever.

28.  SURRENDER OF PREMISES AT END OF TERM. No surrender of the Demised
Premises for the remainder of the Sub-Lease term hereunder shall be binding
upon Landlord unless accepted by Landlord in writing. Without limiting the
generality of the foregoing, it is agreed that the receipt or acceptance of
the keys to the Demised Premises by Landlord shall not constitute an
acceptance of a surrender of the Demised Premises. Tenant agrees that upon
the termination of this Sub-Lease it will surrender, yield up, and deliver
the Demised Premises in good and clean condition, except the effects of
reasonable wear and tear and depreciation arising from lapse of time, or
damage without fault or liability of Tenant. Tenant shall remove its

                                  15

<PAGE>

inventory, equipment, furniture, and trade fixtures as provided in paragraph
27 above; and any property which Tenant in its discretion elects not to
remove shall be presumed to be abandoned and shall thereupon be the sole and
exclusive property of Landlord.

29.  REMOVAL OF SPECIAL BUILDOUT IMPROVEMENTS. The Demised Premises shall be
restored at the end of this Sub-Lease to a condition comparable to the
remaining portion of the Demised Premises so that the space may be used for
normal production, office or warehouse space, including the following: (i)
the special buildout improvements in the production room shall be removed
(however, the part of the special reinforcement walls for the containment
room which are located underground need not be removed unless it interferes
with the restoration of the space for normal production, office or warehouse
usage), and (ii) the main electrical entrance and panel for the Demised
Premises located in the production room shall be moved to a corner of the
building and a mechanical room built around them, all in conformance with
code requirements (all referred to hereinafter as the "Restoration").

     A.   Tenant shall be liable for all expenses ("Restoration expense")
incurred by Landlord in such Restoration of the Demised Premises. Restoration
expense shall also include Basic Rental for the period of such Restoration.


     B.   Landlord shall bill Tenant for the costs of such Restoration
expense. Any bill submitted by Landlord and not paid within 10 days from the
date thereof shall constitute a default hereunder and the amount unpaid shall
bear interest at 16% per annum.


     C.   Landlord shall have, in addition to the lien given by law, and
Tenant does hereby grant to Landlord, a security interest as provided by the
Uniform Commercial Code of Iowa, in all fixtures and equipment and all
replacements, proceeds and substitutions therefor, kept and used on said
premises by Tenant, as security for payment of any and all amounts that may
be due under this Sub-lease. Tenant shall sign any and all further documents
necessary or helpful to preserve and perfect such security interest,
including a separate Iowa Bar Association form security agreement and/or UCC
financing statements, as Landlord requests.

30.  PARAGRAPH TITLES. The titles of the various paragraphs of this Sub-Lease
have been inserted merely as a manner of convenience and for reference only,
and shall not be deemed in any manner to define, limit, or describe the scope
or intent of the particular paragraphs to which they refer or to affect the
meaning or construction of the language contained in the body of such
paragraphs.

31.  SEVERABILITY. If any provision of this Sub-Lease shall be declared
legally invalid or unenforceable, then the remaining provisions of this
Sub-Lease nevertheless shall continue in full force and effect and shall be
enforceable to the fullest extent permitted by law.

32.  TIME OF ESSENCE. Time is of the essence of this Sub-Lease, and all
provisions of this Sub-Lease relating to the time of performance of any
obligation under this Sub-Lease shall be strictly construed.

                                  16



<PAGE>

33.  GOVERNING LAW. This Sub-Lease shall be governed by and construed in
accordance with the laws of the state in which the Demised Premises are
located.

34.  MULTIPLE COUNTERPARTS. This Sub-Lease may be executed in multiple
counter parts, each of which shall be deemed to be an original for all
purposes.

35.  BINDING AGREEMENT. All rights and liabilities herein given to or imposed
upon the respective parties hereto shall extend to and bind the respective
heirs, executors, administrators, personal representatives, successors, and
assigns of such parties. No rights, however, shall inure to the benefit of
any assigns of Tenant unless the assignment thereof to such assignee has been
approved by Landlord in writing, if such approval is required by this
Sub-Lease.

36.  RELATIONSHIP OF PARTIES. Nothing contained in this Sub-Lease shall be
deemed or construed by the parties hereto or by any third party to create the
relationship of principal and agent or of partnership or of joint venture
between the parties hereto, it being understood and agreed that neither the
method of computation of rent, nor any other provision contained herein, nor
any acts of the parties hereto shall be deemed to create any relationship
between the parties hereto other than the relationship of Landlord and Tenant.

37.  EXECUTION REQUIRED. The submission of this document for examination does
not constitute an offer to lease, or a reservation of or option for the
Demised Premises and shall become effective only upon execution by both
Tenant and Landlord.

38.  NUMBER AND GENDER. Where the context of this Sub-Lease requires,
singular words shall be read as if plural, plural words shall be read as if
singular, and words of neuter gender shall be read as if masculine or
feminine.

39.  ENTIRE AGREEMENT. Tenant and Landlord hereby agree that this Sub-Lease
as written represents the entire agreement between the parties hereto and
that it supersedes any other agreements, written or verbal, between the
parties hereto pertaining to the Demised Premises or the subject matter
hereof. This Sub-Lease may not be amended or supplemented orally but only by
an agreement in writing which has been signed by the party against whom
enforcement is sought.

     This Sub-Lease agreement constitutes the "mutually acceptable separate
agreement" contemplated by paragraph I of that certain Letter of
Understanding between Titan Corporation and Cloverleaf Cold Storage Co. dated
April 7, 1999, the other terms of which remain in full force and effect.

40.  BROKER'S COMMISSION. Landlord and Tenant covenant, warrant and represent
to each other that there was no broker instrumental in consummating this
Sub-Lease and that no conversations or prior negotiations were had by
Landlord or Tenant with any broker concerning the renting of the Demised
Premises. Landlord and Tenant agree to indemnify and hold each other harmless
against and from all liabilities resulting from or arising out of any
conversations or negotiations had by the other directly with any broker.

                                17

<PAGE>

41.  CONSENT. In any instance where the consent or approval of either party
is required under the terms of this Sub-Lease, such consent or approval shall
not be unreasonably withheld. Landlord and Tenant agree to execute and
deliver any instruments in writing necessary to carry out any agreement,
term, condition, or assurance in this Sub-Lease whenever occasion shall arise
and request for such instruments shall be made.

42.  EXHIBITS. The following exhibits are attached to and considered part of
this agreement:
                Exhibit "A" - Floor Plan of Demised Premises.
                Exhibit "B" -Additional refrigeration billing formula.

43.  MEMORANDUM OF LEASE. At Tenant's option, and upon its demand, a Memoran-
dum of Lease for recording purposes, in form and content acceptable to
Landlord, but in no way altering the terms of this Sub-Lease, shall be
executed by the parties hereto for Tenant's recording at its sole expense,
provided such Memorandum of Sub-Lease states that Tenant's interest hereunder
is subordinated to any mortgage, trust deed or other encumbrance as more
specifically provided in paragraph 24 above.


44.  TENANT DEFAULTS. In the event Tenant shall fail or neglect to perform
all Tenant's obligations required hereunder, Landlord shall have the right,
but not the duty, to perform said obligation of Tenant, and the sum or sums
of money paid by Landlord for the purposes aforesaid, plus interest thereon
at 16% per annum from the date of each such payment or performance,
shall be deemed to be additional rent and shall become due and payable by
Tenant to Landlord with the next monthly installment of rent thereafter
becoming due or payable hereunder. All rentals or additional rents which are
not paid when due shall accrue interest from and after such due date at the
aforementioned rate until full payment.


45.  ATTORNEY FEES. In the event that either party hereto shall be required
to institute any legal proceeding to enforce the other party's compliance
with the terms hereof or to obtain possession of the Demised Premises or to
collect any sums due from the other party hereunder, the party instituting
the proceeding shall be entitled to recover, if that party instituting the
proceeding shall prevail therein, and the other party hereby agrees to pay
the reasonable attorney fees incurred by the party instituting the proceeding
by reason of such proceeding.

                                    18



<PAGE>

46.  ESTOPPEL CERTIFICATE. Each party hereto shall, upon demand from the
other, execute and deliver to the requesting party an estoppel certificate in
such form and content as requested by the requesting party, attesting to the
compliance to date of the requesting party with the terms and conditions of
this Sub-Lease and such other matters as requested by the requesting party
concerning the tenancy of Tenant hereunder. In the event that the party
providing such estoppel certificate asserts any default by the requesting
party which would prevent the party providing the estoppel certificate from
attesting to such a certificate, the party requested to provide the estoppel
certificate shall set forth such alleged default or defaults upon the
certificate in detail or attest to the fact that those listed defaults are
the only defaults by the requesting party hereunder.

     Signed as of the date and year first above written.

    CLOVERLEAF COLD STORAGE CO.            THE TITAN CORPORATION

By:                                        By: /s/ L. L. Fowler
   ------------------------------             ---------------------------
                                                L. L. FOWLER
Its:                                       Its: CORP. V. P.
    -----------------------------              --------------------------

STATE OF __________________)
                           )ss
COUNTY OF _________________)


     On ______________, 2000, before me, the undersigned, a Notary Public
in and for said State, personally came ________________________ to me
personally known to be the ____________________ of said Cloverleaf Cold
Storage Co., who is personally known to me to be the identical person whose
name is affixed to the foregoing Sub-Lease Agreement, and acknowledged the
execution thereof to be his Voluntary act and deed as such officer and the
voluntary act and deed of said corporation.

                                                  -----------------------------
                                                  Notary Public

STATE OF ___________________)
                            ) ss
COUNTY OF __________________)

     On ____________________, 2000, before me, the undersigned, a Notary
Public in and for said State, personally came _______________________, to me
personally known to be the __________ of said THE TITAN CORPORATION, who is
personally known to me to be the identical person whose name is affixed to
the foregoing Sub-Lease Agreement, and acknowledged the execution thereof to
be his voluntary act and deed as such officer and tile voluntary act and deed
of said corporation

                                                  -----------------------------
                                                  Notary Public


                                       19

<PAGE>

CALIFORNIA ALL-PURPOSE ACKNOWLEDGMENT

State of California       /
                          / ss.
County of San Diego       /

On April 13, 2000, before me,    Ann I. Miller, Notary Public,
   --------------             --------------------------------------------
       Date                   Name and Title of Officer (e.g., "Jane Doe,
                              Notary Public")

personally appeared                   L.L. Fowler                      ,
                   ----------------------------------------------------
                                     Name of Signer

/X/ personally known to me
/ / proved to me on the basis of satisfactory evidence

to be the person whose name is subscribed to the within instrument and
acknowledged to me that he executed the same in his authorized capacity, and
that by his signature on the instrument the person, or the entity upon behalf
of which the person acted, executed the instrument.

WITNESS my hand and official seal.

                                   /s/ Ann I. Miller
     [SEAL]                   ---------------------------------
Place Notary Seal Above          Signature of Notary Public


---------------------------------- OPTIONAL ----------------------------------

THOUGH THE INFORMATION BELOW IS NOT REQUIRED BY LAW, IT MAY PROVE VALUABLE TO
  PERSONS RELYING ON THE DOCUMENT AND COULD PREVENT FRAUDULENT REMOVAL AND
             REATTACHMENT OF THIS FORM TO ANOTHER DOCUMENT.


DESCRIPTION OF ATTACHED DOCUMENT
Title or Type of Document:     Sublease Agreement
                          -------------------------------------------------

Document Date:      9/1/99        Number of Pages:      21
              ------------------                   ------------------------

Signer(s) Other Than Named Above:           N/A
                                  -----------------------------------------

CAPACITY CLAIMED BY SIGNER

Signer's Name:      L.L. Fowler
              -------------------------------------        RIGHT THUMBPRINT
/ / Individual                                                OF SIGNER
/X/ Corporate Officer -- Title:  Corp. V.P.               -----------------
/ / Partner -- / / Limited  / / General                   Top of thumb here
/ / Attorney in Fact
/ / Trustee
/ / Guardian or Conservator
/ / Other:
           ---------------------------------------

Signer Is Representing:    The Titan Corp.
                        --------------------------


<PAGE>

                                                                   EXHIBIT  A


                           [...***...]




                           *Confidential Treatment Requested


<PAGE>

                                                                     EXHIBIT B

                    ADDITIONAL REFRIGERATION BILLING FORMULA

At Tenant's request, Landlord has installed two additional refrigeration
systems: (1) a water chiller used to cool Tenant's equipment and for re-heat
conditioned air; and (2) an outside air make-up unit to replenish
refrigerated air that is exhausted by Tenant's ozone exhaust safety system.
Finally, there is a credit item for removal of standard refrigeration loads
for a portion of the Demised Premises.

WATER CHILLER. The installed water chiller provides [...***...] of
Refrigeration (TR) that is used as follows: [...***...] for each of two
linear accelerators and [...***...] for chilling of air re-heated to provide
precisely conditioned air

AIR MAKE-UP. A continuously operating [...***...] air make-up unit is
installed equipped with a [...***...] refrigeration coil. The refrigeration
load is dependant on outside temperature and wet bulb. Average temperature in
Sioux City, Iowa is approximately 59.0DEG.F. Average refrigeration load will
therefore approximate [...***...].

CREDIT. Use of the water chiller associated air and re-heat conditioning
eliminates approximately six tons of refrigeration load from the south end of
the building.

<TABLE>

<S>                                       <C>                   <C>
Installed Cost per TR                     $[...***...]          Elec. Rates (incl. Tax & franchise fee)

Useful Life (years)                        [...***...]                 Demand       $[...***...]
Annual Maintenance (per TR)               $[...***...]                 Consumption  $[...***...]
                                          ------
Annual Equip Cost per TR                  $[...***...]          Electrical Load per TR is        [...***...] kW

              Water Chiller Base Load                           Tons Ref.      Mo. Cost       Total Mo. Cost
                          Equipment Cost                        [...***...]    $[...***...]
                          Demand Cost                           [...***...]    $[...***...]
                          Base Consumption                      [...***...]    $[...***...]
                                                                                               $[...***...]
              Air Make-Up
                          Equipment Cost                        [...***...]    $[...***...]
                          Demand Cost                           [...***...]    $[...***...]
                          Average Consumption                   [...***...]    $[...***...]
                                                                                               $[...***...]
              Credit
                          Equipment Cost                        [...***...]    $[...***...]
                          Demand Cost                           [...***...]    $[...***...]
                          Consumption                           [...***...]    $[...***...]
                                                                                                [...***...]
                                                                  Monthly Base Cost            $[...***...]
                                                                                 markup         [...***...]%
                                                                  Monthly Base Charge          $[...***...]

Hourly Charge per hour per linear accelerator
                          Consumption                           [...***...]    $[...***...]    $[...***...]

</TABLE>

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