<PAGE>

                                                                   EXHIBIT 10.16


Lease made as of the 23rd day of July, 1999, between INVESTMENT PROPERTIES
ASSOCIATES hereinafter referred to as "Landlord" or "Lessor", and PARTMINER,
INC. hereinafter referred to as "Tenant" or "Lessee".

Witnesseth: Landlord hereby leases to Tenant and Tenant hereby hires from
Landlord ROOM 1901-3 (said space is hereinafter called the "premises") in the
building known as 245 Fifth Avenue ("the building") in the County of New York,
City of New York, for a term of 2 years & 6 months to commence on the 1st day of
September 1999, and to expire on the 28th day of February 2002, or until such
term shall sooner end as in Article 12 and elsewhere herein provided, both dates
inclusive, at a fixed annual rental (subject to Articles 23 and 41) at the
annual rate of $248,064.00 per annum (9/1/99-2/28/02) payable in equal monthly
installments in advance on the first day of each month, except that the first
installment of rent due under this lease shall be paid by Tenant upon its
execution of this lease, unless this lease be a renewal.

Landlord and Tenant covenant and agree:


                                   PURPOSE.

     1.   Tenant shall use and occupy the premises only for offices relating to
Tenant's business, and for no other purpose. Office for tenant's internet firm.


                           RENT AND ADDITIONAL RENT.

     2.   Tenant agrees to pay rent as herein provided at the office of Landlord
or such other place as Landlord may designate, payable in United States legal
tender, by cash, or by good and sufficient check drawn on a New York City
Clearing House Bank, and without any set off or deduction whatsoever. Any sum
other than fixed rent payable hereunder shall be deemed additional rent and due
on demand.

                                  ASSIGNMENT.

     3.   Neither Tenant nor Tenant's legal representatives or successors in
interest by operation of law or otherwise, shall assign, mortgage or otherwise
encumber this lease, or sublet or permit all or part of the premises to be used
by others, without the prior written consent of Landlord in each instance. The
transfer of a majority of the issued and outstanding capital stock of any
corporate tenant or sublessee of this lease or a majority of the total interest
in any partnership tenant or sublessee, however accomplished, and whether in a
single transaction or in a series of related or unrelated transactions, and the
conversion of a tenant or sublessee entity to either a limited liability company
or a limited liability partnership shall be deemed an assignment of this lease
or of such sublease. The merger or consolidation of a corporate tenant or
sublessee where the net worth of the resulting corporation is less than the net
worth of the tenant or sublessee immediately prior to such merger or
consolidation shall be deemed an assignment of this lease or of such sublease.
If without Landlord's written consent this lease is assigned, or the premises
are sublet or occupied by anyone other than Tenant, Landlord may accept the rent
from such assignee, subtenant or occupant, and apply the net amount thereof to
the rent herein reserved, but no such assignment, subletting, occupancy or
acceptance of rent shall be deemed a waiver of this covenant. Consent by
Landlord to an assignment or subletting shall not relieve Tenant from the
obligation to obtain Landlord's written consent to any further assignment or
subletting. In no event shall any permitted sublessee assign or encumber its
sublease or further sublet all or any portion of its sublet space, or otherwise
suffer or permit the sublet space or any part thereof to be used or occupied by
others, without Landlord's prior written consent in each instance. A
modification, amendment or extension of a sublease shall be deemed a sublease.

                                   DEFAULT.

     4.   Landlord may terminate this lease on three (3) days' notice: (a) if
rent or additional rent is not paid within ten (10) days after written notice
from Landlord; or (b) if Tenant shall have failed to cure a default in the
performance of any covenant of this lease (except the payment of rent), or any
rule or regulation hereinafter set forth, within fifteen (15) days after written
notice thereof from Landlord, or if default cannot be completely cured in such
time, if Tenant shall not promptly proceed to cure such default within said
fifteen (15) days or shall not complete the curing of such default with due
diligence; or (c) when and to the extent permitted by law, if a petition in
bankruptcy shall be filed by or against Tenant or if Tenant shall make a general
assignment for the benefit of creditors, or receive the benefit of any
insolvency or reorganization act; or (d) if a receiver or trustee is appointed
for any portion of Tenant's property and such appointment is not vacated within
twenty (20) days; or (e) if an execution or attachment shall be issued under
which the premises shall be taken or occupied or attempted to be taken or
occupied by anyone other than Tenant; or (f) if the premises become and remain
vacant or deserted for a period often (10) days; or (g) if Tenant shall default
beyond any grace period under any other lease between Tenant and Landlord; or
(h) if Tenant shall fail to move into or take possession of the premises within
fifteen (15) days after commencement of the term of this lease.

     At the expiration of the three (3) day notice period, this lease and any
rights of renewal or extension thereof shall terminate as completely as if that
were the date originally fixed for the expiration of the term of this lease, but
Tenant shall remain liable as hereinafter provided.

                                RELETTING, ETC.

     5.   If Landlord shall re-enter the premises on the default of Tenant, by
summary proceedings or otherwise: (a) Landlord may re-let the premises or any
part thereof as Tenant's agent, in the name of Landlord, or otherwise, for a
term shorter or longer than the balance of the term of this lease, and may grant
concessions or free rent. (b) Tenant shall pay Landlord any deficiency between
the rent hereby reserved and the net amount of any rents collected by Landlord
for the remaining term of this lease, through such reletting. Such deficiency
shall become due and payable monthly, as it is determined. Landlord shall have
no obligation to re-let the premises, and its failure or refusal to do so, or
failure to collect rent on re-letting, shall not affect Tenant's liability
hereunder. In computing the net amount of rents collected through such
re-letting. Landlord may deduct all expenses incurred in obtaining possession
or re-letting the premises, including legal expenses and fees, brokerage fees,
the cost of restoring the premises to good order, and the cost of all
alterations and decorations deemed necessary by Landlord to effect re-letting.
In no event shall Tenant be entitled to a credit or repayment for rerental
income which exceeds the sums payable by Tenant hereunder or which covers a
period after the original term of this lease. (c) Tenant hereby expressly waives
any right of redemption granted by any present or future law. "Re-enter" and
"re-entry" as used in this lease are not restricted to their technical legal
meaning. In the event of a breach or threatened breach of any of the covenants
or provisions hereof Landlord shall have the right of injunction. Mention herein
of any particular remedy shall not preclude Landlord from any other available
remedy. (d) Landlord shall recover as liquidated damages, in addition to accrued
rent and other charges, if Landlord's re-entry is the result of Tenant's
bankruptcy, insolvency, or reorganization, the full rental for the maximum
period allowed by any act relating to bankruptcy, insolvency or reorganization.

     If Landlord re-enters the premises for any cause, or if Tenant abandons or
vacates the premises, and after the expiration of the term of this lease, any
property left in the premises by Tenant shall be deemed to have been abandoned
by Tenant, and Landlord shall have the right to retain or dispose of such
property in any manner without any obligation to account therefor to Tenant. If
Tenant shall at any time default hereunder, and if Landlord shall institute an
action or summary proceedings against Tenant based upon such default, then
Tenant will reimburse Landlord for the legal expenses and fees thereby incurred
by Landlord.

                          LANDLORD MAY CURE DEFAULTS.

     6.   If Tenant shall default in performing any covenant or condition of
this lease, subject to prior written notice to Tenant by Landlord, Landlord may
perform the same for the account of Tenant, and if Landlord, in connection
therewith, or in connection with any default by Tenant, makes any expenditures
or incurs any obligations for the payment of money, including but not limited to
attorney's fees, such sums so paid or obligations incurred shall be deemed to be
additional rent hereunder, and shall be paid  by Tenant to Landlord within five
(5) days of rendition of any bill or statement therefor, and if Tenant's lease
term shall have expired at the time of the making of such expenditures or
incurring of such obligations, such sums shall be recoverable by Landlord as
damages.

<PAGE>

                                 ALTERATIONS.

     7.  Tenant shall make no alteration, addition or improvement in the
premises, without the prior written consent of Landlord, and then only by
contractors or mechanics and in such manner and with such materials as shall be
approved by Landlord. All alterations, additions or improvements to the
premises, including window and central air conditioning equipment and duct work,
except movable office furniture and equipment installed at the expense of
Tenant, shall, unless Landlord elects otherwise in writing, become the property
of Landlord, and shall be surrendered with the premises at the expiration or
sooner termination of the term of this lease. Any such alterations, additions
and improvements which Landlord shall designate, shall be removed by Tenant and
any damage repaired, at Tenant's expense, prior to the expiration of the term of
this lease. 1

                                    LIENS.

     8.2 With respect to contractors, subcontractors, materialmen and laborers,
and architects, engineers and designers, for all work or materials to be
furnished to Tenant at the premises, Tenant agrees to obtain and deliver to
Landlord written and unconditional waiver of mechanics liens upon the premises
or the building, after payments to the contractors, etc., subject to any then
applicable provisions of the Lien law. Notwithstanding the foregoing, Tenant at
its expense shall cause any lien filed against the premises or the building, for
work or materials claimed to have been furnished to Tenant, to be discharged of
record within thirty (30) days after notice thereof.

                                   REPAIRS.

     9.  Tenant shall take good care of the premises and the fixtures and
appurtenances therein, and shall make all repairs necessary to keep them in good
working order and condition, including structural repairs when those are
necessitated by the act, omission or negligence of Tenant or its agents,
employees or invitees. During the term of this lease, Tenant may have the use of
any air-conditioning equipment located in the premises, and Tenant, at its own
cost and expense, shall maintain and repair such equipment and shall reimburse
Landlord, in accordance with Article 41 of this lease, for electricity consumed
by the equipment. The exterior walls of the building, the windows and the
portions of all window sills outside same are not part of the premises demised
by this lease, and Landlord hereby reserves all rights to such parts of the
building.

                                 DESTRUCTION.

     10. If the premises shall be partially damaged by fire or other casualty,
the damage shall be repaired at the expense of Landlord, but without prejudice
to the rights of subrogation, if any, of Landlord's insurer. Landlord shall not
be required to repair or restore any of Tenant's property or any alteration or
leasehold improvement made by or for Tenant at Tenant's expense. The rent shall
abate in proportion to the portion of the premises not usable by Tenant.
Landlord shall not be liable to Tenant for any delay in restoring the premises,
Tenant's sole remedy being the right to an abatement of rent, as above provided.
If the premises are rendered wholly untenantable by fire or other casualty and
if Landlord shall decide not to restore the premises, or if the building shall
be so damaged that Landlord shall decide to demolish it or to rebuild it
(whether or not the premises have been damaged), Landlord may within ninety (90)
days after such fire or other cause give written notice to Tenant of its
election that the term of this lease shall automatically expire no less than ten
(10) days after such notice is given. Notwithstanding the foregoing, each party
shall look first to any insurance in its favor before making any claim against
the other party for recovery for loss or damage resulting from fire or other
casualty, and to the extent that such insurance is in force and collectible and
to the extent permitted by law, Landlord and Tenant each hereby releases and
waives all right of recovery against the other or any one claiming through or
under each of them by way of subrogation or otherwise. The foregoing release and
waiver shall be in force only if both releasors' insurance policies contain a
clause providing that such a release or waiver shall not invalidate the
insurance and also, provided that such a policy can be obtained without
additional premiums. Tenant hereby expressly waives the provisions of Section
227 of the Real Property law and agrees that the foregoing provisions of this
Article shall govern and control in lieu thereof.

                                 END OF TERM.

     11. Tenant shall surrender the premises to Landlord at the expiration or
sooner termination of this lease in good order and condition, except for
reasonable wear and tear and damage by fire or other casualty, and Tenant shall
remove all of its property. Tenant agrees it shall indemnify and save Landlord
harmless against all costs, claims, loss or liability resulting from delay by
Tenant in so surrendering the premises, including, without limitation, any
claims made by any succeeding tenant founded on such delay. Additionally, the
parties recognize and agree that other damage to Landlord resulting from any
failure by Tenant timely to surrender the premises will be substantial, will
exceed the amount of monthly rent theretofore payable hereunder, and will be
impossible of accurate measurement. Tenant therefore agrees that if possession
of the premises is not surrendered to Landlord within one (1) day after the date
of the expiration or sooner termination of the term of this lease, then Tenant
will pay Landlord as liquidated damages for each month and for each portion of
any month during which Tenant holds over in the premises after expiration or
termination of the term of this lease, a sum equal to two (2) times the average
rent and additional rent which was payable per month under this lease during the
last six months of the term thereof. The aforesaid obligations shall survive the
expiration or sooner termination of the term of this lease. At any time during
the term of this lease, Landlord may exhibit the premises to prospective
purchasers or mortgagees of Landlord's interest therein. During the last year of
the term of this lease, Landlord may exhibit the premises to prospective
tenants.

                       SUBORDINATION AND ESTOPPEL, ETC.

     12. Tenant has been informed and understands that Landlord is the Tenant
under a lease of the land and entire building of which the premises form a part
(hereinafter called the "Master Lease"). This lease is and shall be subject and
subordinate to the Master Lease and all other ground and underlying leases and
to all mortgages which may now or hereafter affect such leases or the real
property of which the premises form a part, and to all renewals, modifications,
consolidations, replacements and extensions thereof. This Article shall be
self-operative and no further instrument of subordination shall be necessary. In
confirmation of such subordination, Tenant shall execute promptly any
certificate that Landlord may request. In the event that the Master Lease or
any other ground or underlying lease is terminated or any mortgage foreclosed,
this lease shall not terminate or be terminable by Tenant (except as hereinafter
provided as to Master Lease expiration of term) unless Tenant was specifically
named in any termination or foreclosure judgment or final order. In the event
that the Master Lease or any other ground or underlying lease is terminated as
aforesaid, or expires (as hereinafter provided), or if the interests of Landlord
under this lease are transferred by reason of or assigned in lieu of foreclosure
or other proceedings for enforcement of any mortgage, or if the holder of any
mortgage acquires a lease in substitution therefor, then tenant will, at the
option to be exercised in writing by the landlord under the Master Lease or such
purchaser, assignee or lessee, as the case may be, (i) attorn to it and will
perform for its benefit all the terms, covenants and conditions of this lease on
the Tenant's part to be performed with the same force and effect as if said
landlord or such purchaser, assignee or lessee, were the landlord originally
named in this lease, or (ii) enter into a new lease with said lessor or such
purchaser, assignee or lessee,  as landlord, for the remaining term of this
lease and otherwise on the same terms, conditions and rentals as herein
provided. If the current term of the Master Lease shall expire prior to the date
set forth herein for the expiration of this lease, then, unless Landlord, at its
sole option, shall have elected to extend or renew the term of the Master Lease,
or unless the lessor under the Master Lease elects that the Tenant attorn or
enter into a new lease as aforesaid, the term of this lease shall expire on the
date of expiration of the Master Lease, notwithstanding the later expiration
date hereinabove set forth. If the Master Lease is renewed, then the term of
this lease shall expire as hereinabove set forth. From time to time, Tenant, on
at least ten (10) days' prior written request by Landlord will deliver to
Landlord a statement in writing certifying that this lease is unmodified and in
full force and effect (or if there shall have been modifications, that the same
is in full force and effect as modified and stating the modification) and the
dates to which the rent and other charges have been paid and stating whether or
not the Landlord is in default in performance of any covenant, agreement, or
condition contained in this lease and, if so, specifying each such default of
which Tenant may have knowledge. 3

                                 CONDEMNATION.

     13. If the whole or any substantial part of the premises shall be condemned
by eminent domain or acquired by private purchase in lieu thereof for any public
or quasi-public purpose, this lease shall terminate on the date of the vesting
of title through such proceeding or purchase, and Tenant shall have no claim
against Landlord for the value of any unexpired portion of the term of this
lease, nor shall Tenant be entitled to any part of the condemnation award or
private purchase price. If less than a substantial part of the premises is
condemned, this lease shall not terminate, but rent shall abate in proportion to
the portion of the premises condemned.

                             REQUIREMENTS OF LAW.

     14. (a) Tenant at its expense shall comply with all laws, orders and
regulations of any governmental authority having or asserting jurisdiction over
the premises, which shall impose any violation, order or duty upon Landlord or
Tenant with respect to the premises or the use or occupancy thereof including,
without limitation, compliance in the premises with all City, State and Federal
laws, rules and regulations on the disabled or handicapped, on fire safety and
on hazardous materials. The foregoing shall not require Tenant to do structural
work.

     (b) Tenant shall require every person engaged by him to clean any window in
the premises from the outside, to use the equipment and safety devices required
by Section 202 of the labor law and the rules of any governmental authority
having or asserting jurisdiction.

     (c) Tenant at its expense shall comply with all requirements of the New
York Board of Fire Underwriters, or any other similar body affecting the
premises and shall not use the premises in a manner which shall increase the
rate of fire insurance of Landlord or of any other tenant, over that in effect
prior to this lease. If Tenant's use of the premises increases the fire
insurance rate, Tenant shall reimburse Landlord for all such increased costs.
That the premises are being used for the purpose set forth in Article 1 hereof
shall not relieve Tenant from the foregoing duties, obligations and expenses.

                           CERTIFICATE OF OCCUPANCY.

     15. Tenant will at no time use or occupy the premises in violation of the
certificate of occupancy issued for the building. The statement in this lease of
the nature of the business to be conducted by Tenant shall not be deemed to
constitute a representation or guaranty by Landlord that such use is a lawful or
permissible in the premises under the certificate of occupancy for the building.
<PAGE>

                                  POSSESSION.

     16. If Landlord shall be unable to give possession of the premises on the
commencement date of the term because of the retention of possession of any
occupant thereof alteration or construction work, or for any other reason except
as hereinafter provided, Landlord shall not be subject to any liability for such
failure. 4 In such event, this lease shall stay in full force and effect,
without extension of its term. However, the rent hereunder shall not commence
until the premises are available for occupancy by Tenant. If delay in possession
is due to work, changes or decorations being made by or for Tenant, or is
otherwise caused by Tenant, there shall be no rent abatement and the rent shall
commence on the date specified in this lease. If permission is given to Tenant
to occupy the demised premises or other premises prior to the date specified as
the commencement of the term, such occupancy shall be deemed to be pursuant to
the terms of this lease, except that the parties shall separately agree as to
the obligation of Tenant to pay rent for such occupancy. The provisions of this
Article are intended to constitute an "express provision to the contrary" within
the meaning of Section 223(a), New York Real Property Law. 5

                               QUIET ENJOYMENT.

     17. Landlord covenants that if Tenant pays the rent and performs all of
Tenant's other obligations under this lease, Tenant may peacebly and quietly
enjoy the demised premises, subject to the terms, covenants and conditions of
this lease and to the ground leases, underlying leases and mortgages
hereinbefore mentioned.

                                RIGHT OF ENTRY.

     18. Tenant shall permit Landlord to erect and maintain pipes and conduits
in and through the premises. Landlord or its agents shall have the right to
enter or pass through the premises at all times, by master key, by reasonable
force or otherwise, to examine the same, and to make such repairs, alterations
or additions as it may deem necessary or desirable to the premises or the
building, and to take all material into and upon the premises that may be
required therefor. Such entry and work shall not constitute an eviction of
Tenant in whole or in part, shall not be grounds for any abatement of rent, and
shall impose no liability on Landlord by reason of inconvenience or injury to
Tenant's business. Landlord shall have the right at any time, without the same
constituting an actual or constructive eviction, and without incurring any
liability to Tenant, to change the arrangement and/or location of entrances or
passageways, windows, corridors, elevators, stairs, toilets, or other public
parts of the building, and to change the name or number by which the building is
known.

                                  VAULT SPACE.

     19. Anything contained in any plan or blueprint to the contrary
notwithstanding, no vault or other space not within the building property line
is demised hereunder. Any use of such space by Tenant shall be deemed to be
pursuant to a license, revocable at will by Landlord, without diminution of the
rent payable hereunder. If Tenant shall use such vault space, any fees taxes or
charges made by any governmental authority for such space shall be paid by
Tenant.

                                  INDEMNITY.

     20. Tenant shall indemnify, defend and save Landlord harmless from and
against any liability or expense arising from the use or occupation of the
premises by Tenant, or anyone on the premises with Tenant's permission, or from
any breach of this lease.

                             LANDLORD'S LIABILITY.

     21. This lease and the obligations of Tenant hereunder shall in no way be
affected because Landlord is unable to fulfill any of its obligations or to
supply any service, by reason of strike or other cause not within Landlord's
control. Landlord shall have the right, without incurring any liability to
Tenant, to stop any service because of accident or emergency, or for repairs,
alterations or improvements, necessary or desirable in the judgment of Landlord,
until such repairs, alterations or improvements shall have been completed.
Landlord shall not be liable to Tenant or anyone else, for any loss or damage
to person, property or business, unless due to the negligence of Landlord nor
shall Landlord be liable for any latent defect in the premises or the building.
Tenant, during the term of this lease, shall carry public liability and property
damage insurance, from a company authorized to do business in New York, with
limitations acceptable to Landlord, which policy or policies shall name the
Landlord and its designees as additional insureds. Evidence of the policies,
and of their timely renewal, shall be delivered to Landlord. All such insurance
shall contain an agreement by the insurance company that the policy or policies
will not be cancelled or the coverage changed, without thirty (30) days' prior
written notice to the Landlord. Tenant agrees to look solely to Landlord's
estate and interest in the land and building, or the lease of the building or of
the land and building, and the demised premises, for the satisfaction of any
right or remedy of Tenant for the collection of a judgment (or other judicial
process) requiring the payment of money by Landlord, in the event of any
liability by Landlord, and no other property or assets of Landlord shall be
subject to levy, execution or other enforcement procedure for the satisfaction
of Tenant's remedies under or with respect to this lease, the relationship of
landlord and tenant hereunder, or Tenant's use and occupancy of the demised
premises or any other liability of Landlord to Tenant (except for negligence).

                            CONDITION OF PREMISES.

     22. Tenant acknowledges that Landlord has made no representation or
promise, except as herein expressly set forth. Tenant agrees to accept the
premises "as is", except for any work which Landlord has expressly agreed in
writing to perform, and, provided that, the premises must be broom clean with
all mechanical systems in good working order.

                          COST OF LIVING ADJUSTMENTS.

     23. The fixed annual rent reserved in this lease and payable hereunder
shall be adjusted, as of the times and in the manner set forth in this Article:

     (a) Definitions: For the purposes of this Article, the following
definitions shall apply:

     (i)   The term "Base Year" shall mean the full calendar year 2000.

     (ii)  The term "Price Index" shall mean the "Consumer Price Index"
published by the Bureau of Labor Statistics of the U.S. Department of Labor, All
Items. New York, N.Y.--Northeastern, N.J., all urban consumers (presently
denominated "CPI-U"), or a successor or substitute index appropriately adjusted.

     (iii) the term "Price Index for the Base Year" shall mean the average of
the monthly All Items Price Indexes for each of the 12 months of the Base Year.

     (b) Effective as of each January and July subsequent to the Base Year,
there shall be made a cost of living adjustment of the fixed annual rental rate
payable hereunder. The July adjustment shall be based on the percentage
difference between the Price Index for the preceding month of June and the Price
Index for the Base Year. The January adjustment shall be based on such
percentage difference between the Price Index for the preceding month of
December and the Price Inded for the Base Year.

     (i) In the event the Price Index for June in any calendar year during the
term of this lease reflects an increase over the Price Index for the Base Year,
then the fixed annual rent herein provided to be paid as of the July 1st
following such month of June (unchanged by any adjustments under this Article)
shall be multiplied by the percentage difference between the Price Index for
June and the Price Index for the Base Year, and the resulting sum shall be added
to such fixed annual rent, effective as of such July 1st. Said adjusted fixed
annual rent shall thereafter be payable hereunder, in equal monthly
installments, until it is readjusted pursuant to the terms of this lease.

     (ii) In the event the Price Index for December in any calendar year during
the term of this lease reflects an increase over the Price Index for the Base
Year, then the fixed annual rent herein provided to be paid as of the January
1st following such month of December (unchanged by any adjustments under this
Article) shall be multiplied by the percentage difference between the Price
Index for December and the Price Index for the Base Year, and the resulting sum
shall be added to such fixed annual rent effective as of such January 1st. Said
adjusted fixed annual rent shall thereafter be payable hereunder, in equal
monthly installments, until it is readjusted pursuant to the terms of this
lease.

     The following illustrates the intentions of the parties hereto as to the
computation of the aforementioned cost of living adjustment in the annual rent
payable hereunder.

          Assuming that said fixed annual rent is $10,000, that the Price Index
     for the Base Year was 102.0 and that the Price Index for the month of June
     in a calendar year following the Base Year was 105.0, then the percentage
     increase thus reflect, i.e., 2.941% (3.0/102.0) would be multiplied by
     $10,000, and said fixed annual rent would be increased by $294.10 effective
     as of July 1st of said calendar year.

     In the event that the Price Index ceases to use 1982-84=100 as the basis
of calculation, or if a substantial change is made in the terms or number of
items contained in the Price Index, then the Price Index shall be adjusted to
the figure that would have been arrived at had the manner of computing the
Price Index in effect at the date of this lease not been altered. In the event
such Price Index (or a successor or substitute index) is not available, a
reliable governmental or other non-partisan-publication evaluating the
information theretofore used in determining the Price Index shall be used.

     (c) Landlord will cause statements of the cost of living adjustments
provided for in subdivision (b) to be prepared in reasonable detail and
delivered to Tenant.

     (d) In no event shall the fixed annual rent originally provided to be paid
under this lease (exclusive of the adjustments under this Article) be reduced
by virtue of this Article.

     (e) Any delay or failure of Landlord, beyond July or January of any year,
computing or billing for the rent adjustments hereinabove provided, shall not
constitute a waiver of or in any way impair the continuing obligation of
Tenant to pay such rent adjustments hereunder.

     (f) Notwithstanding any expiration or termination of this lease prior to
the lease expiration date (except in the case of a cancellation by mutual
agreement) Tenant's obligation to pay rent as adjusted under this Article shall
continue and shall cover all periods up to the lease expiration date, and shall
survive any expiration or termination of this lease.

                                TAX ESCALATION.

     24. Tenant shall pay to Landlord, as additional rent, tax escalation in
accordance with this Article:

     (a) For purposes of this lease the rentable square foot area of the
presently demised premises shall be deemed to be 7752 square feet.

     (b) Definitions: For the purpose of this Article, the following definitions
shall apply:

          (i) The term "base tax year" as hereinafter set forth for the
determination of real estate tax escalation, shall mean the New York City real
estate tax year commencing July 1, 1999 and ending June 30, 2000.


<PAGE>

          (ii) The term "The Percentage", for purposes of computing tax
escalation, shall mean .0273 percent (2.73%). The Percentage has been computed
on the basis of a fraction, the numerator of which is the rentable square foot
area of the demised premises and the denominator of which is the total rentable
square foot area of the office and commercial space in the building project. The
parties acknowledge and agree that the total rentable square foot area of the
office and commercial space in the building project shall be deemed to be
283,756 sq. ft.

          (iii) The term "the building project" shall mean the aggregate
combined parcel of land on a portion of which are the improvements of which the
demised premises form a part, with all the improvements thereon, said
improvements being a part of the block and lot for tax purposes which are
applicable to the aforesaid land.

          (iv) The term "comparative year" shall mean the twelve (12) months
following the base tax year, and each subsequent Period of twelve (12) months
(or such other Period of twelve (12) months occurring during the term of this
lease as hereafter may be duly adopted as the tax year for real estate tax
purposes by the City of New York).

          (v) The term "real estate taxes" shall mean the total of all taxes and
special or other assessments levied, assessed or imposed at any time by any
governmental authority upon or against the building project, and also any tax or
assessment levied, assessed or imposed at any time by any governmental authority
in connection with the receipt of income or rents from said building project to
the extent that same shall be in lieu of all or a portion of any of the
aforesaid taxes or assessments, or additions or increases thereof, upon or
against said building project. If, due to a future change in the method of
taxation or in the taxing authority, or for any other reason, a franchise,
income, transit, profit or other tax or governmental imposition, however
designated, shall be levied against landlord in substitution in whole or in part
for the real estate taxes, or in lieu of additions to or increases of said real
estate taxes, then such franchise, income, transit, profit or other tax or
governmental imposition shall be deemed to be included within the definition of
"real estate taxes" for the purposes hereof. As to special assessments which are
payable over a period of time extending beyond the term of this lease, only a
pro rata portion thereof covering the portion of the term of this lease
unexpired at the time of the imposition of such assessment, shall be included in
"real estate taxes". If by law, any assessment may be paid in installments,
then, for the purposes hereof (a) such assessment shall be deemed to have been
payable in the maximum number of installments permitted by law and (b) there
shall be included in real estate taxes, for each comparative year in which such
installments may be paid, the installments of such assessment so becoming
payable during such comparative year, together with interest payable during such
comparative year.

          (vi) Where more than one assessment is imposed by the City of New York
for any tax year, whether denominated an "actual assessment" or a "transitional
assessment" or otherwise, then the phrases herein "assessed value" and
"assessments" shall mean whichever of the actual, transitional or other
assessment is designated by the City of New York as the taxable assessment for
that tax year.

          (vii) The phrase "real estate taxes payable during the base tax year"
shall mean that amount obtained by multiplying the assessed value of the land
and buildings of the building project for the base tax year by the tax rate for
the base tax year for each $100 of such assessed value.

     (c) 1. In the event that the real estate taxes payable for any comparative
year shall exceed the amount of the real estate taxes payable during the base
tax year, tenant shall pay to landlord, as additional rent for such comparative
year, an amount equal to The Percentage of the excess. Before or after the start
of each comparative year, Landlord shall furnish to Tenant a statement of the
real estate taxes payable for such comparative year, and a statement of the real
estate taxes payable during the base tax year. If the real estate taxes payable
for such comparative year exceed the real estate taxes payable during the base
tax year, additional rent for such comparative year, in an amount equal to The
Percentage of the excess, shall be due from Tenant to Landlord, and such
additional rent shall be payable by Tenant to Landlord with ten (10) days after
receipt of the aforesaid statement. The benefit of any discount for any earlier
payment or prepayment of real estate taxes shall accrue solely to the benefit of
Landlord, and such discount shall not be subtracted from the real estate taxes
payable for any comparative year.

     Additionally, Tenant shall pay to Landlord, on demand, a sum equal to The
Percentage of any business improvement district assessment payable by the
building project.

     2. Should the real estate taxes payable during the base tax year be reduced
by final determination of legal proceedings, settlement or otherwise, then, the
real estate taxes payable during the base tax year shall be correspondingly
revised, the additional rent theretofore paid or payable hereunder for all
comparative years shall be recomputed on the basis of such reduction, and tenant
shall pay to Landlord as additional rent, within ten (10) days after being
billed therefor, any deficiency between the amount of such additional rent as
theretofore computed and the amount thereof due as the result of such
recomputations. Should the real estate taxes payable during the base tax year be
increased by such final determination of legal proceedings, settlement or
otherwise, then appropriate recomputation and adjustment also shall be made.

     3. If after Tenant shall have made a payment of additional rent under this
subdivision (c), Landlord shall receive a refund of any portion of the real
estate taxes payable for any comparative year after the base tax year on which
such payment of additional rent shall have been based, as a result of a
reduction of such real estate taxes by final determination of legal proceedings,
settlement or otherwise, Landlord shall within ten (10) days after receiving the
refund pay to Tenant The Percentage of the refund less The Percentage of
expenses (including attorneys' and appraisers' fees) incurred by Landlord in
connection with any such application or proceeding. If prior to the payment of
taxes for any comparative year, Landlord shall have obtained a reduction of that
comparative year's assessed valuation of the building project, and therefore of
said taxes, then the term "real estate taxes" for that comparative year shall be
deemed to include the amount of Landlord's expenses in obtaining such reduction
in assessed valuation, including attorneys' and appraisers' fees.

     4. The statements of the real estate taxes to be furnished by Landlord as
provided above shall be certified by Landlord and shall constitute a final
determination as between Landlord and Tenant of the real estate taxes for the
Periods represented thereby, unless Tenant within thirty (30) days after they
are furnished shall give a written notice to Landlord that it disputes their
accuracy or their appropriateness, which notice shall specify the particular
respects in which the statement is inaccurate or inappropriate. If Tenant shall
so dispute said statement then, pending the resolution of such dispute, tenant
shall pay the additional rent to Landlord in accordance with the statement
furnished by Landlord.

     5. In no event shall the fixed annual rent under this lease (exclusive of
the additional rents under this Article) be reduced by virtue of this Article.

     6. If the commencement date of the term of this lease is not the first day
of the first comparative year, then the additional rent due hereunder for such
first comparative year shall be a proportionate share of said additional rent
for the entire comparative year, said proportionate share to be based upon the
length of time that the lease term will be in existence during such first
comparative year. Upon the date of any expiration or termination of this lease
(except termination because of Tenant's default) whether the same be the date
hereinabove set forth for the expiration of the term or any prior or subsequent
date, a proportionate share of said additional rent for the comparative year
during which such expiration or termination occurs shall immediately become due
and payable by Tenant to Landlord, if it was not theretofore already billed and
paid. The said proportionate share shall be based upon the length of time that
this lease shall have been in existence during such comparative year. Landlord
shall promptly cause statements of said additional rent for that comparative
year to be prepared and furnished to lessee. Landlord and Tenant shall thereupon
make appropriate adjustments of amounts then owing.

     7. Landlord's and Tenant's obligations to make the adjustments referred to
in subdivision (6) above shall survive any expiration or termination of this
lease.

     8. Any delay or failure of lessor in billing any tax escalation hereinabove
provided shall not constitute a waiver of or in any way impair the continuing
obligation of lessee to pay such tax escalation hereunder.

                                 JURY WAIVER.

     26. Landlord and Tenant hereby waive trial by jury in any action,
proceeding or counterclaim involving any matter whatsoever arising out of or in
any way connected with this lease, the relationship of landlord and tenant,
Tenant's use or occupancy of the premises (except for personal injury or
property damage) or involving the right to any statutory relief or remedy.
Tenant will not interpose any counterclaim of any nature in any summary
proceeding.

                                NO WAIVER, ETC.

     27. No act or omission of Landlord or its agents shall constitute an actual
or constructive eviction, unless Landlord shall have first received written
notice of Tenant's claim and shall have had a reasonable opportunity to meet
such claim. In the event that any payment herein provided for by Tenant to
Landlord shall become overdue for a period in excess of ten (10) days, then at
Landlord's option a "late charge" shall become due and payable to Landlord, as
additional rent, from the date it was due until payment is made at the following
rates: for individual and partnership Tenants, said late charge shall be
computed at the maximum legal rate of interest; for corporate or governmental
entity Tenants the late charge shall be computed at one point twenty-five
percent (1.25%) per month unless there is an applicable maximum legal rate of
interest which then shall be used. No act or omission of Landlord or its agents
shall constitute an acceptance of a surrender of the premises, except a writing
signed by Landlord. The delivery of keys to Landlord or its agents shall not
constitute a termination of this lease or a surrender of the premises.
Acceptance by Landlord of less than the rent herein provided shall at Landlord's
option be deemed on account of earliest rent remaining unpaid. No endorsement on
any check, or letter accompanying rent, shall be deemed an accord and
satisfaction, and such check may be cashed without prejudice to Landlord. No
waiver of any provision of this lease shall be effective,
<PAGE>

unless such waiver be in writing signed by Landlord. This lease contains the
entire agreement between the parties, and no modification thereof shall be
binding unless in writing and signed by the party concerned. Tenant shall
comply with the rules and regulations printed in this lease, and any reasonable
modifications thereof or additions thereto. Landlord shall not be liable to
Tenant for the violation of such rules and regulations by any other tenant.
Failure of Landlord to enforce any provision of this lease, or any rule or
regulation, shall not be construed as the waiver of any subsequent violation of
a provision of this lease, or any rule or regulation. This lease shall not be
affected by nor shall Landlord in any way be liable for the closing, darkening
or bricking up of windows in the premises, for any reason, including as the
result of construction on any property of which the premises are not a part or
by Landlord's own acts.

                         OCCUPANCY AND USE BY TENANT.

     (A)  The parties recognize and agree that the damage to Landlord resulting
from any breach of the covenants in subdivision (A) (deleted) hereof will be
extremely substantial, will be far greater that the rent payable for the balance
of the term of this lease, and will be impossible of accurate measurement. The
parties therefore agree that in the event of a breach or threatened breach of
the said covenants, in addition to all of Landlord's other rights and remedies,
at law or in equity or otherwise, Landlord shall have the right of injunction to
preserve Tenant's occupancy and use. The words "become vacant or deserted" as
used elsewhere in this lease shall include Tenant's failure to occupy or use as
by this Article required.

     (B)  If Tenant breaches either of the covenants in subdivision (A)
(deleted) above, and this lease be terminated because of such default, then, in
addition to Landlord's rights of reentry, restoration, preparation for and
rerental, and anything elsewhere in this lease to the contrary notwithstanding,
Landlord shall retain its right to judgment on and collection of Tenant's
aforesaid obligation to make a single payment to Landlord of a sum equal to the
total of all rent and additional rent reserved for the remainder of the original
term of this lease, subject to future credit or repayment to Tenant in the event
of any rerenting of the premises by Landlord, after first deducting from
rerental income all expenses incurred by Landlord in reducing to judgment or
otherwise collecting Tenant's aforesaid obligation, and in obtaining possession
of restoring, preparing for and re-letting the premises. In no event shall
Tenant be entitled to a credit or repayment for rerental income which exceeds
the sums payable by Tenant hereunder or which covers a period after the original
term of this lease.

                                    NOTICES.

     29.  Any bill, notice or demand from Landlord to Tenant, may be delivered
personally at the premises or sent by registered or certified mail. 6. Such
bill, notice or demand shall be deemed to have been given at the time of
delivery or mailing. Any notice from Tenant to Landlord must be sent by
registered or certified mail to the last address designated in writing by
Landlord.

                                     WATER.

     30.  Tenant shall pay the amount of Landlord's cost for all water used by
Tenant for any purpose other than ordinary lavatory uses, and any sewer rent or
tax based thereon. Landlord may install a water meter to measure Tenant's water
consumption for all purposes and Tenant agrees to pay for the installation and
maintenance thereof and for water consumed as shown on said meter. If water is
made available to Tenant in the building or the demised premises through a meter
which also supplies other premises, or without a meter, then Tenant shall pay to
Landlord $75.00 per month for water.

                               SPRINKLER SYSTEM.

     31.  If there shall be a "sprinkler system" in the demised premises for any
period during this lease, Tenant shall pay $75.00 per month, for sprinkler
supervisory service. If such sprinkler system is damaged by any act or omission
of Tenant or its agents, employees, licensees or visitors, Tenant shall restore
the system to good working condition at its own expense. If the New York Board
of Fire Underwriters, the New York Fire Insurance Exchange, the Insurance
Services Office or any governmental authority requires the installation or any
alteration to a sprinkler system by reason of Tenant's occupancy or use of the
premises, including any alteration necessary to obtain the full allowance for a
sprinkler system in the fire insurance rate of Landlord, or for any other
reason, Tenant shall make such installation or alteration promptly, and at its
own expense.

                             HEAT, ELEVATOR, ETC.

     32.  Landlord shall provide elevator service during all usual business
hours including Saturdays until 1 P.M., except on Sundays, State holidays,
Federal holidays, or Building Service Employees Union Contract holidays.
Landlord shall furnish heat to the premises during the same hours on the same
days in the cold season in each year. Landlord may remove Tenant's extraordinary
refuse from the building and Tenant shall pay the cost thereof. If the elevators
in the building are manually operated, Landlord may convert to automatic
elevators at any time, without in any way affecting Tenant's obligations
hereunder.

                               SECURITY DEPOSIT.

     33.  Tenant has deposited with Landlord the sum of $45,713.80 as security
for the performance by Tenant of the terms of this lease. Landlord may use any
part of the Security to satisfy any default of Tenant and any damages or rent
deficiency before or after re-entry by Landlord. Tenant shall, upon demand,
deposit with Landlord the full amount so used, in order that Landlord shall have
the full security deposit on hand at all times during the term of this lease. If
Tenant shall comply fully with the terms of this lease, the security shall be
returned to Tenant after the date fixed as the end of the lease. In the event of
a sale or lease of the building containing the premises, Landlord may transfer
the security to the purchaser or tenant, and Landlord shall thereupon be
released from all liability for the return of the security. This provision shall
apply to every transfer or assignment of the security to a new Landlord, Tenant
shall have no legal power to assign or encumber the security herein described.

                                 ELECTRICITY.

     34.  Terms and conditions with respect to electricity rent inclusion, or
with respect to sub-meeting, as the case may be, and general conditions with
respect to either, are set forth in Article 41 in the Rider annexed to and made
part of this lease.

                                 RENT CONTROL.

     35.  In the event the fixed annual rent or additional rent or any part
thereof provided to be paid by Tenant under the provisions of this lease during
the demised term shall become uncollectible or shall be reduced or required to
be reduced or refunded by virtue of any Federal, State, County or City law,
order or regulation, or by any direction of a public officer or body pursuant to
law, or the orders, rules, code or regulations of any organization or entity
formed pursuant to law, whether such organization or entity be public or
private, then Landlord, at its option, may at any time thereafter terminate this
lease, by not less than thirty (30) days' written notice to Tenant, on a date
set forth in said notice, in which event this lease and the term hereof shall
terminate and come to an end on the date fixed in said notice as if the said
date were the date originally fixed herein for the termination of the demised
term. Landlord shall not have the right so to terminate this lease if Tenant
within such period of thirty (30) days shall in writing lawfully agree that the
rentals, herein reserved are a reasonable rental and agree to continue to pay
said rentals, and if such agreement by Tenant shall then be legally enforceable
by Landlord.

                                   SHORING.

     36.  Tenant shall permit any person authorized to make an excavation on
land adjacent to the building containing the premises to do any work within the
premises necessary to preserve the wall of the building from injury or damage,
and Tenant shall have no claim against Landlord for damages or abatement of rent
by reason thereof.

                          EFFECT OF CONVEYANCE, ETC.

     37.  If the building containing the premises shall be sold, transferred or
leased, or the lease thereof transferred or sold, Landlord shall be relieved of
all future obligations and liabilities hereunder and the purchaser, transferee
or tenant of the building shall be deemed to have assumed and agreed to perform
all such obligations and liabilities of Landlord hereunder. In the event of such
sale, transfer or lease, Landlord shall also be relieved of all existing
obligations and liabilities hereunder, provided that the purchaser, transferee
or tenant of the building assumes in writing such obligations and liabilities.

                       RIGHTS OF SUCCESSORS AND ASSIGNS.

     38.  This lease shall bind and inure to the benefit of the heirs,
executors, administrators, successors, and, except as otherwise provided herein,
the assigns of the parties hereto. If any provision of any Article of this lease
or the application thereof to any person or circumstances shall, to any extent,
be invalid or unenforceable, the remainder of that Article, or the application
of such provision to persons or circumstances other than those as to which it is
held invalid or unenforceable, shall not be affected thereby, and each provision
of said Article and of this lease shall be valid and be enforced to the fullest
extent permitted by law.

                                   CAPTIONS.

     39.  The captions herein are inserted only for convenience, and are in no
way to be construed as a part of this lease or as a limitation of the scope of
any provision of this lease.

                               LEASE SUBMISSION.

     40.  Landlord and Tenant agree that this lease is submitted to Tenant on
the understanding that it shall not be considered an offer and shall not bind
Landlord in any way unless and until (i) Tenant has duly executed and delivered
duplicate originals thereof to Landlord and (ii) Landlord has executed and
delivered one of said originals to Tenant.
<PAGE>

              SEE RIDER(S) ANNEXED HERETO AND MADE A PART HEREOF

     In Witness Whereof, Landlord and Tenant have executed this lease as of the
day and year first above written.

<TABLE>
<S>                                                              <C>
                                                                 INVESTMENT PROPERTIES ASSOCIATES
---------------------------------------------------              C/O HELMSLEY SPEAR, INC. AGENTS         (L.S.)
               Witness for Landlord                              ----------------------------------------------

---------------------------------------------------              BY: /s/ Irving Schneider                (L.S.)
               Witness for Tenant                                    ------------------------------------------
                                                                     IRVING SCHNEIDER, C.O.O.

                                                                 BY: /s/ Darold R. Stagner CFO              (L.S.)
                                                                     ------------------------------------------
                                                                     PARTMINER, INC.

                                                         ACKNOWLEDGEMENTS.

                                                                 State of New York  )
                                                                 County of New York )  ss.:
State of New York  )                                             On the day of                               , 19    , before me
County of New York )  ss.:                                       personally came
On the       day of                     ,19    , before me       to me known, who being by me duly sworn, did depose and say that he
personally came                                                  resides at No.
to me known and known to me to be the individual described       that he is the                of
in, and who executed, the foregoing instrument, and              the corporation described in, and which executed, the foregoing
acknowledged to me that he executed the same.                    instrument; and that he signed h       name thereto by authority
                                                                 of the Board of Directors of said corporation.

                                    ----------------------                                                   ----------------------
                                             Notary Public                                                            Notary Public
</TABLE>

                                   GUARANTY.

     For Value Received and in consideration of the letting of the premises
within mentioned to the within named Tenant, the undersigned do hereby covenant
and agree, to and with the Landlord and the Landlord's legal representatives,
that if default shall at any time be made by the said Tenant in the payment of
the rent and the performance of the covenants contained in the within lease, on
the Tenant's part to be paid and performed, that the undersigned will well and
truly pay the said rent, or any arrears thereof that may remain due unto said
Landlord, and also pay all damages that may arise in consequence of the
non-performance of said covenants, or either of them, without requiring notice
of any such default from the Landlord. The undersigned hereby waives all right
to trial by jury in any action or proceeding hereinafter instituted by the
Landlord, to which the undersigned may be a party.

     IN WITNESS WHEREOF, the undersigned has      set      hand and seal this
day of            19

<TABLE>
<S>                                                              <C>
___________________________________________________              ________________________________________________(L.S.)


___________________________________________________              ________________________________________________(L.S.)
                                                                 to me known and known to me to be the individual described in, and
State of New York  )                                             who executed the foregoing Guaranty and acknowledged to me that he
County of New York )  ss.:                                       executed the same.
On the      day of                 ,19     ,before me
personally came

                                                                                                              ----------------------
                                                                                                                       Notary Public
</TABLE>


<PAGE>

           ---------------------------------------------------------
              RIDER ANNEXED TO AND MADE A PART OF LEASE BETWEEN

              INVESTMENT PROPERTIES ASSOCIATES              LANDLORD
              ----------------------------------------------

              AND PARTMINER, INC.                           TENANT
                  ------------------------------------------
          ---------------------------------------------------------

                         RULES AND REGULATIONS REFERRED
                               TO IN THIS LEASE

  1.  No animals, birds, bicycles or vehicles shall be brought into or kept in
the premises. The premises shall not be used for manufacturing or commercial
repairing or for sale or display of merchandise or as a lodging place, or for
any immoral or illegal purpose, nor shall the premises be used for a public
stenographer or typist; barber or beauty shop; telephone, secretarial or
messenger service; employment, travel or tourist agency; school or classroom;
commercial document reproduction; or for any business other than specifically
provided for in the tenant's lease. Tenant shall not cause or permit in the
premises any disturbing noises which may interfere with occupants of this or
neighboring buildings, any cooking or objectionable odors, or any nuisance of
any kind, or any inflammable or explosive fluid, chemical or substance.
Canvassing, soliciting and peddling in the building are prohibited, and each
tenant shall cooperate so as to prevent the same.

  2.  The toilet rooms and other water apparatus shall not be used for any
purposes other than those for which they were constructed, and no sweepings,
rags, ink, chemicals or other unsuitable substances shall be thrown therein.
Tenant shall not throw anything out of doors, windows or skylights, or into
hallways, stairways or elevators, nor place food or objects on outside window
sills. Tenant shall not obstruct or cover the halls, stairways and elevators, or
use them for any purpose other than ingress and egress to or from tenant's
premises, nor shall skylights, windows, doors and transoms that reflect or admit
light into the building be covered or obstructed in any way.

  3.  Tenant shall not place a load upon any floor of the premises in excess of
the load per square foot which such floor was designed to carry and which is
allowed by law. Landlord reserves the right to prescribe the weight and position
of all safes in the premises. Business machines and mechanical equipment shall
be placed and maintained by tenant, at tenant's expense, only with Landlord's
consent and in settings approved by Landlord to control weight, vibration, noise
and annoyance. Smoking or carrying lighted cigars, pipes or cigarettes in the
elevators of the building is prohibited. If the premises are on the ground floor
of the building the tenant thereof at its expense shall keep the sidewalks and
curb in front of the premises clean and free from ice, snow, dirt and rubbish.

  4.  Tenant shall not move any heavy or bulky materials into or out of the
building without Landlord's prior written consent, and then only during such
hours and in such manner as Landlord shall approve. If any material or equipment
requires special handling, tenant shall employ only persons holding a Master
Rigger's License to do such work, and all such work shall comply with all legal
requirements. Landlord reserves the right to inspect all freight to be brought
into the building, and to exclude any freight which violates any rule,
regulation or other provision of this lease.

  5.  No sign, advertisement, notice or thing shall be inscribed, painted or
affixed on any part of the building, without the prior written consent of
Landlord. Landlord may remove anything installed in violation of this provision,
and Tenant shall pay the cost of such removal. Interior signs on doors and
directories shall be inscribed or affixed by Landlord at Tenant's expense.
Landlord shall control the color, size, style and location of all signs,
advertisements and notices. No advertising of any kind by Tenant shall refer to
the building, unless first approved in writing by Landlord.

  6.  No article shall be fastened to, or holes drilled or nails or screws
driven into, the ceilings, walls, doors or other portions of the premises, nor
shall any part of the premises be painted, papered or otherwise covered, or in
any way marked or broken, without the prior written consent of Landlord.

  7.  No existing locks shall be changed, nor shall any additional locks or
bolts of any kind be placed upon any door or window by Tenant, without the prior
written consent of Landlord. At the termination of this lease, Tenant shall
deliver to Landlord all keys for any portion of the premises or building. Before
leaving the premises at any time, Tenant shall close all windows and close and
lock all doors.

  8.  No Tenant shall purchase or obtain for use in the premises any spring
water, ice, towels, food, bootblacking, barbering or other such service
furnished by any company or person not approved by Landlord. Any necessary
exterminating work in the premises shall be done at Tenant's expense, at such
times, in such manner and by such company as Landlord shall require. Landlord
reserves the right to exclude from the building, from 6:00 p.m. to 8:00 am., and
at all hours on Sunday and legal holidays, all persons who do not present a pass
to the building signed by Landlord. Landlord will furnish passes to all persons
reasonably designated by Tenant. Tenant shall be responsible for the acts of all
persons to whom passes are issued at Tenant's request.

  9.  Whenever Tenant shall submit to Landlord any plan, agreement or other
document for Landlord's consent or approval, Tenant agrees to pay Landlord as
additional rent, on demand, an administrative fee equal to the sum of the
reasonable fees of any architect, engineer or attorney employed by Landlord to
review said plan, agreement or document and Landlord's administrative costs for
same.

  10.  The use in the demised premises of auxiliary heating devices, such as
portable electric heaters, heat lamps or other devices whose principal function
at the time of operation is to produce space heating, is prohibited.

  In case of any conflict or inconsistency between any provisions of this lease
and any of the rules and regulations as originally or as hereafter adopted, the
provisions of this lease shall control.
<PAGE>

                           RIDER ANNEXED TO AND MADE

                            PART OF A LEASE BETWEEN

                  INVESTMENT PROPERTIES ASSOCIATES, LANDLORD

                          AND PARTMINER, INC., TENANT

                                  ELECTRICITY

41.  Tenant agrees that Landlord may furnish electricity to Tenant on a
"submetering" basis or on a "rent inclusion" basis. Electricity and electric
service, as used herein, shall mean any element affecting the generation,
transmission, and/or distribution or redistribution of electricity, including
but not limited to services which facilitate the distribution of service.

     (A). Submetering: If and so long as Landlord provides electricity to the
demised premises on a submetering basis, Tenant covenants and agrees to purchase
the same from Landlord or Landlord's designated agent at charges, terms and
rates set, from time to time, during the term of this lease by Landlord but not
more than those specified in the service classification in effect on January 1,
1970 pursuant to which Landlord then purchased electric current from the public
utility corporation serving the part of the city where the building is located;
provided however, said charges shall be increased in the same percentage as any
percentage increase in the billing to Landlord for electricity for the entire
building, by reason of increase in Landlord's electric rates or service
classifications, subsequent to January 1, 1970, and so as to reflect any
increase in Landlord's electric charges, including changes in market prices for
electricity from utilities and/or other providers, in fuel adjustments, or by
taxes or charges of any kind imposed on Landlord's electricity purchases or
redistribution, or for any other such reason, subsequent to said date. Any such
percentage increase in Landlord's billing for electricity due to changes in
rates, service classifications, or market prices, shall be computed by the
application of the average consumption (energy and demand) of electricity for
the entire building for the twelve (12) full months immediately prior to the
rate and/or service classification change, or any changed methods of or rules
on billing for same, applied on a consistent basis to the new rate and/or
service classification or market price, and to the service classification and
rate in effect on January 1, 1970. If the average consumption of electricity for
the entire building for said prior twelve (12) months cannot reasonably be
applied and used with respect to changed methods of or rules on billing, then
the percentage shall be computed by the use of the average consumption (energy
and demand) for the entire building for the first three (3) months after such
change, projected to a full twelve (12) months, so as to reflect the different
seasons; and that same consumption, so projected, shall be applied to the
service classification and rate in effect on January 1, 1970. Where more than
one meter measures the service of Tenant in the building, the service rendered
through each meter may be computed and billed separately in accordance with the
rates herein specified. Bills therefore shall be rendered at such times as
Landlord may elect and the amount, as computed from a meter, shall be deemed to
be, and be paid as, additional rent. In the event that such bills are not paid
within five (5) days after the same are rendered, Landlord may, without further
notice, discontinue the service of electric current to the demised premises
without releasing Tenant from any liability under this lease and without

                                     -1-






<PAGE>

Landlord or Landlord's agent incurring any liability for any damage or loss
sustained by lessee by such discontinuance of service. If any tax is imposed
upon Landlord's receipt from the sale, resale or redistribution of electricity
or gas or telephone service to Tenant by any Federal, State, or Municipal
authority, Tenant covenants and agrees that where permitted by law, Tenant's
pro-rata share of such taxes shall be passed on to and included in the bill of,
and paid by, Tenant to Landlord.

     (B). Rent Inclusion: If and so long as Landlord provides electricity to the
demised premises on a rent inclusion basis, Tenant agrees that the fixed annual
rent shall be increased by the amount of the Electricity Rent Inclusion Factor
("ERIF"), as hereinafter defined. Tenant acknowledges and agrees (i) that the
fixed annual rent hereinabove set forth in this lease does not yet, but is to
include an ERIF of $3.15 per rentable square foot per annum to compensate
Landlord for electrical wiring and other installations necessary for, and for
its obtaining and making available to Tenant the redistribution of electric
current as an additional service; and (ii) that said ERIF, which shall be
subject to periodic adjustments as hereinafter provided, has been partially
based upon an estimate of the Tenant's connected electrical load, in whatever
manner delivered to Tenant, which shall be deemed to be the demand (KW), and
hours of use thereof, which shall be deemed to be the energy (KWH), for ordinary
lighting and light office equipment and the operation of the usual small
business machines, including Xerox or other copying machines (such lighting and
equipment are hereinafter called "Ordinary Equipment") during ordinary business
hours ("ordinary business hours" shall be deemed to mean 50 hours per week),
with Landlord providing an average connected load of 4 1/2 watts of electricity
for all purposes per rentable square foot. Any installation and use of equipment
other than Ordinary Equipment and/or any connected load and/or energy usage by
Tenant in excess of the foregoing shall result in adjustment of the ERIF as
hereinafter provided. For purposes of this lease the rentable square foot area
of the presently demised premises shall be deemed to be 7752 square feet.

     If the cost to Landlord of electricity shall have been, or shall be,
increased or decreased subsequent to May 1, 1999 (whether such change occurs
prior to or during the term of this Lease), by change in Landlord's electric
rates or service classifications, or electricity charges, including changes in
market prices, or by any increase, subsequent to the last such electric rate or
service classification change or market price change, in fuel adjustments or
charges of any kind, or by taxes, imposed on Landlord's electricity purchases or
on Landlord's electricity redistribution, or for any other such reason, then the
aforesaid ERIF portion of the fixed annual rent shall be changed in the same
percentage as any such change in cost due to changes in electric rates, service
classifications or market prices, and, also Tenant's payment obligation, for
electricity redistribution, shall change from time to time so as to reflect any
such increase in fuel adjustments or charges, and such taxes. Any such
percentage change in Landlord's cost due to change in Landlord's electric rates
or service classifications or market prices, shall be computed on the basis of
the average consumption of electricity for the building for the twelve full
months immediately prior to the rate change or other such changes in cost,
energy and demand, and any changed methods of or rules on billing for same,
applied on a consistent basis to the new electric rate or service classification
or market price and to the immediately prior existing electric rate or service
classification or market price. If the average consumption (energy and demand)
for the entire building for said prior (12) months cannot reasonably be applied
and used with respect to changed methods of or rules on billing, then the
percentage increase shall be computed by the use of the average consumption
(energy and demand) for the entire building for the first three (3) months after
such change, projected to a full twelve (12) months, so as to reflect the
different seasons; and that same consumption, so projected, shall be applied to
the rate and/or service classification or market price which existed immediately
prior to the change. The parties agree that a reputable,

                                      -2-
<PAGE>

independent electrical consultant firm, selected by Landlord, ("Landlord's
electrical consultant"), shall determine the percentage change for the changes
in ERIF due to Landlord's changed costs, and that Landlord's electrical
consultant may from time to time make surveys in the demised premises of the
electrical equipment and fixtures and use of current. (i) If such survey shall
reflect a connected electrical load in the demised premises in excess of 4 1/2
watts of electricity for all purposes per rentable square foot and/or energy
usage in excess of ordinary business hours (each such excess hereinafter called
"excess electricity") then the connected electrical load and/or the hours of use
portion(s) of the then existing ERIF shall be increased by an amount which is
equal to a fraction of the then existing ERIF, the numerator of which is the
excess electricity (i.e. excess connected load and/or excess usage) and the
denominator of which is the connected load and/or the energy usage which was the
basis of the then existing ERIF. Such fractions shall be determined by
Landlord's electrical consultant. The fixed annual rent shall then be
appropriately adjusted, effective as of the date of any such change in connected
load and/or usage, as disclosed by said survey. (ii) If such survey shall
disclose installation and use of other than Ordinary Equipment, then effective
as of the date of said survey, there shall be added to the ERIF portion of fixed
annual rent (computed and fixed as hereinbefore described) an additional amount
equal to what would be paid under the SC-4 Rate I Service Classification in
effect on May l, 1999 (and not the time-of-day rate schedule) for such load and
usage of electricity, with the connected electrical load deemed to be the demand
(KW) and the hours of use thereof deemed to be the energy (KWH), as
hereinbefore provided, (which addition to the ERIF shall be increased or
decreased by all electricity cost changes of Landlord, as hereinabove provided,
from May 1, 1999 through the date of billing).

     In no event, whether because of surveys, rates or cost changes, or for any
other reason, is the originally specified $3.15 per annum per rentable square
foot ERIF portion of the fixed annual rent (plus any net increase thereof, but
not decrease, by virtue of all electricity rate, service classification or
market price changes of Landlord subsequent to May 1, l999) to be reduced.

    (C). General Conditions: The determinations by Landlord's electrical
consultant shall be binding and conclusive on Landlord and Tenant from and after
the delivery of copies of such determinations to Landlord and Tenant, unless,
within fifteen (15) days after delivery thereof; Tenant disputes such
determination. If Tenant so disputes the determination, it shall, at its own
expense, obtain from a reputable, independent electrical consultant its own
determinations in accordance with the provisions of this Article. Tenant's
consultant and Landlord's consultant then shall seek to agree. If they cannot
agree within thirty (30) days they shall choose a third reputable electrical
consultant, whose cost shall be shared equally by the parties, to make similar
determinations which shall be controlling. (If they cannot agree on such third
consultant within ten (10) days, than either party may apply to the Supreme
Court in the County of New York for such appointment) However, pending such
controlling determinations, Tenant shall pay to Landlord the amount of
additional rent or ERIF in accordance with the determinations of Landlord's
electrical consultant. If the controlling determinations differ from Landlord's
electrical consultant, then the parties shall promptly make adjustment for any
deficiency owed by Tenant or overage paid by Tenant.

     At the option of Landlord, Tenant agrees to purchase from Landlord or its
agents all lamps and bulbs used in the demised premises and to pay for the cost
of installation thereof. Supplementing Article 35 hereof, if all or part of the
submetering additional rent or the ERIF payable in accordance with Subdivision
(A) or (B) of this Article becomes uncollectible or reduced or refunded by
virtue of any law, order or regulation, the parties agree that, at Landlord's
option, in lieu of submetering additional rent or ERIF, and in consideration of
Tenant's use of the building's electrical distribution system and receipt of

                                      -3-
<PAGE>

redistributed electricity and payment by Landlord of consultant's fees and other
redistribution costs, the fixed annual rental rate(s) to be paid under this
lease shall be increased by an "alternative charge" which shall be a sum equal
to $3.15 per year per rentable square foot of the demised premises, changed in
the same percentage as any increases in the cost to Landlord for electricity for
the entire building subsequent to May 1, 1999, because of electric rate, service
classification or market price changes, such percentage change to be computed as
in Subdivision (B) provided.

     Landlord shall not be liable to Tenant for any loss or damage or expense
which Tenant may sustain or incur if either the quantity or character of
electric service is changed or is no longer available or suitable for Tenant's
requirements. Tenant covenants and agrees that at all times its use of electric
current shall never exceed the capacity of existing feeders to the building or
wiring installation. Tenant agrees not to connect any additional electrical
equipment to the building electric distribution system, other than lamps,
typewriters and other small office machines which consume comparable amounts of
electricity, without Landlord's prior written consent, which consent shall not
be unreasonably withheld. Any riser or risers to supply Tenant's electrical
requirements, upon written request of Tenant, will be installed by Landlord, at
the sole cost and expense of Tenant, if, in Landlord's sole judgment, the same
are necessary and will not cause permanent damage or injury to the building or
demised premises or cause or create a dangerous or hazardous condition or entail
excessive or unreasonable alterations, repairs or expense or interfere with or
disturb other tenants or occupants. In addition to the installation of such
riser or risers, Landlord will also at the sole cost and expense of Tenant,
install all other equipment proper and necessary in connection therewith subject
to the aforesaid terms and conditions. The parties acknowledge that they
understand that it is anticipated that electric rates, charges, etc., may be
changed by virtue of time-of-day rates or changes in other methods of billing,
and/or electricity purchases and the redistribution thereof, and fluctuation in
the market price of electricity, and that the references in the foregoing
paragraphs to changes in methods of or rules on billing are intended to
include any such changes. Anything hereinabove to the contrary notwithstanding,
in no event is the submetering additional rent or ERIF, or any "alternative
charge", to be less than an amount equal to the total of Landlord's payments to
public utilities and/or other providers for the electricity consumed by Tenant
(and any taxes thereon or on redistribution of same) plus 5% thereof for
transmission line loss, plus 10% thereof for other redistribution costs. The
Landlord reserves the right, at any time upon thirty (30) days' written notice,
to change its furnishing of electricity to Tenant from a rent inclusion basis to
a submetering basis, or vice versa, or to change to the distribution of less
than all the components of the existing service to Tenant. The Landlord reserves
the right to terminate the furnishing of electricity on a rent inclusion,
submetering, or any other basis at any time, upon thirty (30) days' written
notice to the Tenant, in which event the Tenant may make application directly to
the public utility and/or other providers for the Tenant's entire separate
supply of electric current and Landlord shall permit its wires and conduits, to
the extent available and safely capable, to be used for such purpose, but only
to the extent of Tenant's then authorized load. Any meters, risers, or other
equipment or connections necessary to furnish electricity on a submetering basis
or to enable Tenant to obtain electric current directly from such utility and/or
other providers shall be installed at Landlord's sole cost and expense. Only
rigid conduit or electricity metal tubing (EMT) will be allowed. The Landlord,
upon the expiration of the aforesaid thirty (30) days' written notice to the
Tenant may discontinue furnishing the electric current but this lease shall
otherwise remain in full force and effect. If Tenant was provided electricity on
a rent inclusion basis when it was so discontinued, then commencing when Tenant
receives such direct service and as long as Tenant shall continue to receive
such service, the fixed annual rent payable under this lease shall be reduced by
the amount of the ERIF which was payable immediately prior to such
discontinuance of electricity on a rent inclusion basis.

                                      -4-
<PAGE>

                               DATED JULY, 1999

                                    BETWEEN

                       INVESTMENT PROPERTIES ASSOCIATES

                                      AND

                                PARTMINER, INC.

PAR 42    The tenant agrees that the minimum charge for electricity for said
premises shall be $2,034.90 per month, which ERIF shall be subject to increase
because of rate changes after the date of this lease, or based on tenant's
consumption, as provided in Article 41.

PAR 43    This agreement is prepared by the managing agent for the tenant. It is
not binding upon either party until it is signed by the tenant and the landlord
and returned to the tenant.

PAR 44    Lessor shall cause the public halls and public portions of the
building to be kept clean in accordance with Landlord's customary standards for
the building. Tenant shall at its own expense keep demised premises clean, in
order, to the satisfaction of the Landlord. It is expressly agreed that the
Tenant shall keep the public corridors free of all refuse and shall at no time
store any furniture, cartons, displays or any other articles in said public
corridors. It is the Tenant's sole responsibility for the removal of all its
refuse. In the event that any such item is found in the public corridor or
freight halls, then the Landlord shall have the right to remove such items to
the basement and charge Tenant for storage and moving costs for such work or
arrange with a carting company to remove such refuse for which the Tenant shall
reimburse the Lessor for such expenses. It is also agreed and understood that
hand truck may not be used in the passenger elevators by the Tenant, its
invitees, or any person making deliveries to the Tenant.

PAR 45    Landlord and Tenant each represent and warrant that it has had no
dealings with respect to this transaction with any broker (person, firm or
corporation) other than Helmsley-Spear Inc., and Newmark & Company, and each
party does hereby indemnify and hold the other harmless against all claims for
commissions or other compensation that may be made by anyone else with whom the
other party may have dealt in connection with this transaction. Lessor agrees to
pay a commission to said brokers in accordance with the terms of a separate
agreement.

                                      -5-
<PAGE>

PAR 46    Lessee expressly acknowledges and agrees that Lessor has not made and
is not making, and Lessee, in executing and delivering this Lease, is not
relying upon, any warranties, representations, promises or statements, except,
to the extent that the same are expressly set forth in this lease or on any
other written agreement which may be made between the parties concurrently with
the execution and delivery of this Lease and shall expressly refer to this
Lease. This Lease and said other written agreement(s) made concurrently herewith
are hereinafter referred to as the "lease documents." It is understood and
agreed that all understandings and agreements heretofore had between the parties
are merged in the lease documents, which alone fully and completely express
their agreements and that the same are entered into after full investigation,
neither party relying upon any statement or representation not embodied in the
lease documents, made by the other. Lessor is not required to perform work of
any kind, nature or description to prepare the demised premises for Lessee's
occupancy except as set forth in Paragraph 53 of this Rider hereto.

PAR 47    Lessee shall maintain comprehensive general public liability insurance
against claims for personal injury or death or property damage, occurring in the
premises or the building such insurance to afford protection to the single limit
of not less than One Million Dollars ($1,000,000.00) with respect to any one
occurrence and to the limit of Three Hundred Thousand Dollars ($300,000.00) with
respect to property damage. In addition to the foregoing, the insurance coverage
required under this paragraph shall extend to any contractual liability of
Lessee arising out of the indemnities provided for in this Lease, and the policy
shall be so endorsed. Any insurance coverage required under this paragraph may
be provided under a blanket insurance policy or policies maintained by Lessee
covering other premises, property or assureds in addition to the demised
premises, provided that amounts of insurance are at least equal to the amounts
to be provided by Lessee pursuant to this Article are allocated to the demised
premises under such blanket policy or policies and all such insurance coverage
may be affected by any combination of basic and excess or umbrella coverage.

     Lessor and Lessee hereby each release, and each hereby represent that their
respective casualty insurance policy related to the building and the premises
contains provisions to release (or waive subrogation) and to waive its right to
recover against the other party, its tenants, invitees, customers, its visitors,
agents and employees, from all liability from damage from fire or casualty to
the building or the demised premises, whether the same is caused by negligence
of Lessor or Lessee, and no insurer shall be subrogated to any rights against
Lessor or Lessee with respect to such damage.

PAR 48    Supplementing the provisions of Article 3 hereof, Lessor shall not
unreasonably withhold consent to an assignment of this lease or to subletting of
all or part of the demised premises, provided that, Lessee shall not need
Lessor's consent to assign or sublet all or part of the demised premises to any
parent, subsidiary or other entity of which lessee owns more than fifty percent
(50%), and provided that:

          I.   Any such assignment or subletting shall be made solely upon the
following terms and conditions;

                                      -6-
<PAGE>

          A.   (1) No assignment or subletting shall become effective unless and
until Lessee shall have given Lessor at least 30 days' notice of such proposed
assignment or proposed bona fide subletting, including the terms thereof.
Following Lessor's receipt of such notice, Lessor shall thereupon have the
option, exercisable by written notice within 30 days after receipt of the notice
from Lessee, (i) to terminate this lease (and release Lessee from obligations
under this Lease accruing on or after the date of termination) effective as of
the date of the proposed assignment or the commencement date of the term of such
proposed subletting if the proposed subletting is for the entire demised
premises for the balance of the term.

               (2) If Lessor shall serve Lessee notice of its exercise of
Lessor's option pursuant to paragraph (1) (i), of this Article 48 (I) (A), then
Lessee shall vacate and surrender the demised premises or the portion thereof to
which Lessor's notice related, on or before the date fixed in the Lessor's
notice (which date fixed in Lessor's notice shall be the commencement date of
Lessee's proposed subletting or assignment).

               (3) No proposed sublease or proposed assignment shall be
effective unless and until any option of Lessor provided in subparagraph (I) (A)
(1) has expired or has been expressly waived by Lessor.

               (4) In the event that Lessor has not elected to terminate this
Lease, Lessee shall pay to lessor a sum equal to the following:

                         a.   In the case of a sublease or assignment, an amount
equal to one half of (i) any rents, additional charges of other consideration
paid under the sublease or assignment to Lessee by the Subtenant or assignee
which is in excess of the fixed rent and additional rent payable by Lessee to
Lessor during the term of the sublease or assignment in respect to the subleased
or assigned space pursuant to the terms hereof, and (ii) any other profit or
gain realized by Lessee from any such subletting or assignment, excluding
amounts realized on the sale of Lessee's personal property.

                         b.   The sum payable under this subparagraph (4) shall
be paid to Lessor as additional rent promptly upon receipt thereof, reduced by
the amount of any brokerage, concessions, work costs, and reasonable attorneys'
fees actually paid by Lessee in connection with such assignment or subletting.

          B.   There shall be no material default by Lessee under any of the
 terms, covenants and conditions of this lease (continuing beyond the applicable
 grace and cure periods) at the time that Lessor's consent to any such
 subletting or assignment is requested and on the date of the commencement of
 the term of any such proposed sublease or the effective date of any such
 proposed assignment.

                                      -7-
<PAGE>

          C.   Any such sublease shall provided that the subtenant shall comply
with all applicable terms and conditions of this Lease thereafter to be
performed by the Lessee hereunder. Any such assignment of Lease shall contain an
assumption by the assignee of all of the terms and obligations of this lease to
be performed by the Lessee from and after the effective date thereof.

          D.   (i) Lessee shall, at its cost and expense, make such alterations
as may be required or reasonably deemed necessary by Lessor to physically
separate any sublet space from the balance of the premises demised hereunder and
(ii) comply with any laws or requirements of public authorities relating to such
separation. Lessor shall not be obligated in any way to provide to the sublessee
means of access and egress on the floor to such space.

PAR 49    Lessee shall use the demised premises solely for general office use.
It is expressly agreed by Lessee that the demised premises shall not be used in
whole or in part as a showroom for the sale of display of merchandise of for the
conduct of business requiring significant shipping activities or freight service
to or from the demised premises or the building.

PAR 50         Lessor's Obligations
               --------------------

          (A)  Lessor's Basic Obligation
               -------------------------

               As more specifically provided in this paragraph, Lessor shall
operate and maintain the building (other than that required of lessee in the
demised premises) in a manner appropriate for a first-class office building in
the City of New York. Lessor also agrees that if any building equipment or
machinery outside the demised premises and serving the demised premises and or
common areas shall break down or for any cause (except due to Lessee's
negligence) cease to function properly, Lessor will use reasonable diligence to
repair the same promptly.

          (B)  Maintenance of Building
               -----------------------

               Except with respect to maintenance or repairs made or to be made
by Lessee as indicated in this Lease, and except where necessitated by Lessee's
negligence, Lessor shall maintain and repair or cause to be maintained and
repaired the public portion and structural elements of the building and, insofar
as such is not the obligation of the provider of the utility, building systems
serving the demised premises within the building which are located outside the
boundary of the building.

          (C)  Interruption in Services
               ------------------------

               Should any of the building equipment, machinery, electrical
wiring, pipes or ducts serving the demised premises, or any of the equipment,
machinery, electrical wiring, pipes or ducts installed in the premises by
Lessor, for any cause (except by reason of Lessee's acts or omissions) or reason
cease to function or operate properly, Lessee shall have no claim for abatement
or rebate or rent or damages on account of any interruptions in service
occasioned thereby

                                      -8-
<PAGE>

or resulting therefrom unless such cessation or improper operation has been
caused by Lessor's negligent acts or omissions. Lessor reserves the right to
temporarily suspend any services for repairs, alterations or replacement deemed
necessary or desirable. Lessor shall give notice of such suspension of services
whenever possible.

     (D)  Elevator Service
          ----------------

          Lessor shall provide automatic elevator service to the premises on a
twenty-four (24) hours per day, seven (7) days per week basis.

     (E)  Maintenance Services
          --------------------

          Except where such requirements are caused by Lessee's negligent acts
or omissions, Lessor shall provide maintenance services for the premises and for
the building in which said premises are located which serve the demised premises
as provided below.

          (i)   Elevators shall be kept in good maintenance and repair under an
elevator service contract.

          (ii)  All heating for the premises and the building shall be kept in
good repair adequate to provide the services required under the Lease.

     (F)  Water Services
          --------------

          On a twenty-four (24) hours per day, seven (7) days a week basis,
Lessor shall furnish at no extra charge to Lessee hot and cold domestic water at
all points of supply made available for the general use of Lessee in the
building or otherwise specified in the Lease.

     (G)  Basic Heating Services
          ----------------------

          Heating adequate to heat the premises to 68 degrees during the heating
season (unless a change in the above temperature standards are necessitated by
governmental regulations or guidelines) shall be available at the times
specified in Article 31 of the Lease at no additional charge to Lessee.

     (H)  Access
          ------

          Lessor agrees that Lessee shall have access to the building and the
premises twenty-four (24) hours a day, seven (7) days a week.

                                      -9-

<PAGE>

PAR 51    Lessee agrees to accept these premises "AS IS" in all respects except
for the following:

1.   Existing space shall be in broom clean condition.

2.   All mechanical systems shall be placed in good working order.

3.   Place existing air cooled air conditioning units in good working order and
     maintain same for one full year following commencement date of said lease.

PAR 52    In the event of any inconsistency between the printed portion of this
Lease and this Rider, the terms of this Rider shall control.


                                        INVESTMENT PROPERTIES ASSOCIATES
                                        By: Helmsley-Spear, Inc., as agent

                                        By: /s/ Irving Schneider
                                            -------------------------------
                                            Irving Schneider, C.O.O.

                                        PARTMINER, INC.

                                        By: /s/ Darold R. Stagner
                                            -------------------------------
                                            CFO

                               -10-
<PAGE>

                           RIDER ANNEXED TO AND MADE
                            PART OF A LEASE BETWEEN
                       INVESTMENT PROPERTIES ASSOCIATES,
                      LANDLORD AND PARTMINER, INC., TENANT

     1.   ALTERATIONS. Paragraph 7. At the end of paragraph, add the following:

     "Notwithstanding the foregoing, (i) structural renovations of Tenant in
amounts less than $10,000 shall not require the prior written approval of
Landlord, and (ii) Tenant shall not be required to remove any alterations,
additions and/or improvements which Landlord has approved."

     2.   LIENS. Paragraph 8. Delete the first sentence and replace it with the
following:

     "Prior to commencement of Tenant's structural renovations in the demised
premises, Tenant shall obtain and deliver to Landlord a copy of the renovation
plan or its equivalent, signed by architects to become involved in such work."

     3.   SUBORDINATION AND ESTOPPEL, ETC. Paragraph 12. Add the following at
the end of the paragraph.

     "Notwithstanding the foregoing, the Landlord represents and warrants to
Tenant that no Master Lease exists."

     4.   POSSESSION. Paragraph 16. At the end of the first sentence, add the
following:

     "; provided that, Landlord shall provide Tenant with temporary premises
rent free for a period of up to three (3) weeks in the event that Landlord is
unable to give possession of the premises to Tenant on the commencement date."

     5.   POSSESSION. Paragraph 16. At the end of the paragraph, add the
following:

     "Notwithstanding the foregoing, in the event that the Landlord is unable to
give possession of the premises to Tenant by November 30, 1999, Tenant shall
have the right to terminate the Lease without further obligation, and Tenant's
full security deposit shall be immediately returned to Tenant."









<PAGE>

     6.   NOTICES. Paragraph 29. At the end of the first sentence, add the
following language: ", with a copy sent to the following address:

          PartMiner, Inc.
          432 Park Avenue South, 12/th/ Floor
          New York, New York 10016

          Attention:     General Counsel"

                         INVESTMENT PROPERTIES ASSOCIATES
                         By: Helmsley-Spear, Inc., as agent

                         By: /s/ Irving Schneider
                             ------------------------------
                             Irving Schneider, C.O.O.

                         PARTMINER, INC.


                         By: /s/ Darold R. Stagner      CFO
                             ------------------------------