EXHIBIT 10.12 MASTER LEASE AGREEMENT MASTER LEASE AGREEMENT (the "Master Lease") dated December 30, 1997 by and between COMDISCO, INC. ("Lessor") and FlyCast Communications Corporation ("Lessee"). IN CONSIDERATION of the mutual agreements described...

EXHIBIT 10.12

MASTER LEASE AGREEMENT

MASTER LEASE AGREEMENT (the "Master Lease") dated December 30, 1997 by and
between COMDISCO, INC. ("Lessor") and FlyCast Communications Corporation
("Lessee").

IN CONSIDERATION of the mutual agreements described below, the parties agree as
follows (all capitalized terms are defined in Section 14.18):

1. PROPERTY LEASED.

Lessor leases to Lessee all of the Equipment described on each Summary Equipment
Schedule. In the event of a conflict, the terms of the applicable Schedule
prevail over this Master Lease.

2. TERM.

On the Commencement Date, Lessee will be deemed to accept the Equipment, will be
bound to its rental obligations for each item of Equipment and the term of a
Summary Equipment Schedule will begin and continue through the Initial Term and
thereafter until terminated by either party upon prior written notice received
during the Notice Period. No termination may be effective prior to the
expiration of the Initial Term.

3. RENT AND PAYMENT.

Rent is due and payable in advance on the first day of each Rent Interval at the
address specified in Lessor's invoice. Interim Rent is due and payable when
invoiced. If any payment is not made when due, Lessee will pay a Late Charge on
the overdue amount. Upon Lessee's execution of each Schedule, Lessee will pay
Lessor the Advance specified on the Schedule. The Advance will be credited
towards the final Rent payment is Lessee is not then in default. No interest
will be paid on the Advance.

4. SELECTION; WARRANTY AND DISCLAIMER OF WARRANTIES.

4.1 SELECTION. Lessee acknowledges that it has selected the Equipment and
disclaims any reliance upon statements made by the Lessor, other than as set
forth in the Schedule.

4.2 WARRANTY AND DISCLAIMER OF WARRANTIES. Lessor warrants to Lessee
that, so long as Lessee is not in default, Lessor will not disturb Lessee's
quiet and peaceful possession, and unrestricted use of the Equipment. To the
extent permitted by the manufacturer, Lessor assigns to Lessee during the term
of the Summary Equipment Schedule any manufacturer's warranties for the
Equipment. LESSOR MAKES NO OTHER WARRANTY, EXPRESS OR IMPLIED AS TO ANY MATTER
WHATSOEVER, INCLUDING, WITHOUT LIMITATION, THE MERCHANTABILITY OF THE EQUIPMENT
OR ITS FITNESS FOR A PARTICULAR PURPOSE. Lessor is not responsible for any
liability, claim, loss, damage or expense of any kind (including strict
liability in tort) caused by the Equipment except for any loss or damage caused
by the willful misconduct or negligent acts of Lessor. In no event is Lessor
responsible for special, incidental or consequential damages.

5. TITLE; RELOCATION OR SUBLEASE; AND ASSIGNMENT.

5.1 TITLE. Lessee holds the Equipment subject and subordinate to the
rights of the Owner, Lessor, any Assignee and any Secured Party. Lessee
authorizes Lessor, as Lessee's agent, and at Lessor's expense, to prepare,
execute and file in Lessee's name precautionary Uniform Commercial Code
financing statements showing the interest of the Owner, Lessor, and any Assignee
or Secured Party in the Equipment and to insert serial numbers in Summary
Equipment Schedules as appropriate. Lessee will, at its expense, keep the
Equipment free and clear from any liens or encumbrances of any kind (except any

caused by Lessor) and will indemnify and hold the Owner, Lessor, any Assignee
and Secured Party harmless from and against any loss caused by Lessee's failure
to do so, except where such is caused by Lessor.

5.2 RELOCATION OR SUBLEASE. Upon prior written notice, Lessee may
relocate Equipment to any location within the continental United States provided
(i) the Equipment will not be used by an entity exempt from federal income tax,
and (ii) all additional costs (including any administrative fees, additional
taxes and insurance coverage) are reconciled and promptly paid by Lessee.

Lessee may sublease the Equipment upon the reasonable consent of the Lessor
and the Secured Party. Such consent to sublease will be granted if: (i) Lessee
meets the relocation requirements set out above, (ii) the sublease is expressly
subject and subordinate to the terms of the Schedule, (iii) Lessee assigns its
rights in the sublease to Lessor and the Secured Party as additional collateral
and security, (iv) Lessee's obligation to maintain and insure the Equipment is
not altered, (v) all financing statements required to continue the Secured
Party's prior perfected security interest are filed, and (vi) Lessee executes
sublease documents acceptable to Lessor.

No relocation or sublease will relieve Lessee from any of its obligations
under this Master Lease and the relevant Schedule.

5.3 ASSIGNMENT BY LESSOR. The terms and conditions of each Schedule have
been fixed by Lessor in order to permit Lessor to sell and/or assign or transfer
its interest or grant a security interest in each Schedule and/or the Equipment
to a Secure Party or Assignee. In that event, the term Lessor will mean the
Assignee and any Secured Party. However, any assignment, sale, or other
transfer by Lessor will not relieve Lessor of its obligations to Lessee and will
not materially change Lessee's duties or materially increase the burdens or
risks imposed on Lessee. The Lessee consents to and will acknowledge such
assignments in a written notice given to Lessee. Lessee also agrees that:

(a) The Secured Party will be entitled to exercise all of Lessor's
rights, but will not be obligated to perform any of the obligations of Lessor.
The Secured Party will not disturb Lessee's quiet and peaceful possession and
unrestricted use of the Equipment so long as Lessee is not in default and the
Secured Party continues to receive all Rent payable under the Schedule;

(b) Lessee will pay all Rent and all other amounts payable to the
Secured Party despite any defense or claim which it has against Lessor. Lessee
reserves its right to have recourse directly against Lessor for any defense or
claim; and

(c) Subject to and without impairment of Lessee's leasehold rights in
the Equipment, Lessee holds the Equipment for the Secured Party to the extent of
the Secured Party's rights in that Equipment.

6. NET LEASE; TAXES AND FEES.

6.1 Net Lease. Each Summary Equipment Schedule constitutes a net lease.
Lessee's obligation to pay Rent and all other amounts due hereunder is absolute
and unconditional and is not subject to any abatement, reduction, set-off,
defense, counterclaim, interruption, deferment or recoupment for any reason
whatsoever.

6.2 TAXES AND FEES. Lessee will pay when due or reimburse Lessor for all
taxes, fees or any other charges (together with any related interest or
penalties not arising from the negligence of Lessor) accrued for or arising
during the term of each Summary Equipment Schedule against Lessor, Lessee or the
Equipment by any governmental authority (except only Federal, state, local and
franchise taxes on the capital or the net income of Lessor). Lessor will file
all personal property tax returns for the Equipment

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and pay all such property taxes due. Lessee will reimburse Lessor for property
taxes within thirty (30) days of receipt of an invoice.

7. CARE, USE AND MAINTENANCE; INSPECTION BY LESSOR.

7.1 CARE, USE AND MAINTENANCE. Lessee will maintain the Equipment in good
operating order and appearance, protect the Equipment from deterioration, other
than normal wear and tear, and will not use the Equipment for any purpose other
than that for which it was designed. If commercially available and considered
common business practice for each item of Equipment, Lessee will maintain in
force a standard maintenance contract with the manufacturer of the Equipment or
another party acceptable to Lessor, and will provide Lessor with a complete copy
of that contract. If Lessee has the Equipment maintained by a party other than
the manufacturer or self maintains, Lessee agrees to pay any costs necessary for
the manufacturer to bring the Equipment to then current release, revision and
engineering change levels, and to re-certify the Equipment as eligible for
manufacturer's maintenance at the expiration of the lease term, provided re-
certification is available and is required by Lessor. The lease term will
continue upon the same terms and conditions until re-certification has been
obtained.

7.2 INSPECTION BY LESSOR. Upon reasonable advance notice, Lessee, during
reasonable business hours and subject to Lessee's security requirements, will
make the Equipment and its related log and maintenance records available to
lessor for inspection.

8. REPRESENTATIONS AND WARRANTIES OF LESSEE. Lessee hereby represents,
warrants and covenants that with respect to the Master Lease and each Schedule
executed hereunder:

(a) The Lessee is a corporation duly organized and validly existing
in good standing under the laws of the jurisdiction of its incorporation, is
duly qualified to do business in each jurisdiction (including the jurisdiction
whom the Equipment is, or is to be, located) where its ownership or lease of
property or the conduct of its business requires such qualification, except for
where such lack of qualification would not have a material adverse effect on the
Company's business; and has full corporate power and authority to hold property
under the Master Lease and each Schedule and to enter into and perform its
obligations under the Master Lease and each Schedule.

(b) The execution and delivery by the Lessee of the Master Lease and
each Schedule and its performance thereunder have been duly authorized by all
necessary corporate action on the part of the Lessee, and the Master Lease and
each Schedule are not inconsistent with the Lessee's Articles of Incorporation
or Bylaws, do not contravene any law or governmental rule, regulation or order
applicable to it, do not and will not contravene any provision of, or constitute
a default under, any indenture, mortgage, contract or other instrument to which
it is a party or by which It is bound, and the Master Lease and each Schedule
constitute legal, valid and binding agreements of the Lessee, enforceable in
accordance with their terms, subject to the effect of applicable bankruptcy and
other similar laws affecting the rights of creditors generally and rules of law
concerning equitable remedies.

(c) There are no actions, suits, proceedings or patent claims pending
or, to the knowledge of the Lessee, threatened against or affecting the Lessee
in any court or before any governmental commission, board or authority which, if
adversely determined, will have a material adverse effect on the ability of the
Lessee to perform its obligations under the Master Lease and each Schedule.

(d) The Equipment is personal property and when subjected to use by
the Lessee will not be or become fixtures under applicable law.

(e) The Lessee has no material liabilities or obligations, absolute
or contingent (individually or in the aggregate) except the liabilities and
obligations of the Lessee as set forth in the Financial Statements and
liabilities and obligations which have occurred in the ordinary course of

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business, and which have not been, In any case or in the aggregate, materially
adverse to Lessee's ongoing business.

(f) To the best of the Lessee's knowledge, the Lessee owns,
possesses, has access to, or can become licensed on reasonable terms under all
patents, patent applications, trademarks, trade names, inventions, franchises,
licenses, permits, computer software and copyrights necessary for the operations
of Its business as now conducted, with no known infringement of, or conflict
with, the rights of others.

(g) All material contracts, agreements and instruments to which the
Lessee is a party are in full force and effect in all material respects, and are
valid, binding and enforceable by the Lessee in accordance with their respect
terms, subject to the effect of applicable bankruptcy and other similar laws
affecting the rights of creditors generally, and rules of law concerning
equitable remedies.

9. DELIVERY AND RETURN OF EQUIPMENT.

Lessee hereby assumes the full expense of transportation and in-transit
insurance to Lessee's premises and installation thereat of the Equipment. Upon
termination (by expiration or otherwise) of each Summary Equipment Schedule,
Lessee shall, pursuant to Lessor's instructions and at Lessee's full expense
(including, without limitation, expenses of transportation and in-transit
insurance), return the Equipment to Lessor in the same operating order, repair,
condition and appearance as when received, less normal depreciation and wear and
tear. Lessee shall return the Equipment to Lessor at ▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇,
▇▇▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ ▇▇▇▇▇ or at such other address within the continental United
States as directed by Lessor, provided, however, that Lessee's expense shall be
limited to the cost of returning the Equipment to Lessor's address as set forth
herein. During the period subsequent to receipt of a notice under Section 2,
Lessor may demonstrate the Equipment's operation in place and Lessee will supply
any of its personnel as may reasonably be required to assist in the
demonstrations.

10. LABELING.

Upon request, Lessee will ▇▇▇▇ the Equipment indicating Lessor's interest with
labels provided by Lessor. Lessee will keep all Equipment free from any other
marking or labeling which might be interpreted as a claim of ownership.

11. INDEMNITY.

With regard to bodily injury and property damage liability only, Lessee will
indemnify and hold Lessor, any Assignee and any Secured Party harmless from and
against any and all claims, costs, expenses, damages and liabilities, including
reasonable attorneys' fees, arising out of the ownership (for strict liability
in tort only), selection, possession, leasing, operation, control, use,
maintenance, delivery, return or other disposition of the Equipment during the
term of this Master Lease or until Lessee's obligations under the Master Lease
terminate. However, Lessee is not responsible to a party indemnified hereunder
for any claims, costs, expenses, damages and liabilities occasioned by the
negligent acts of such indemnified party. Lessee agrees to carry bodily injury
and property damage liability insurance during the term of the Master Lease in
amounts and against risks customarily insured against by the Lessee on Equipment
owned by it. Any amounts received by Lessor under that insurance will be
credited against Lessee's obligations under this Section.

12. RISK OF LOSS.

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at least thirty (30) days prior written notice to the Lessor of cancellation or
expiration, and will insure Lessors interests regardless of any breach or
violation by Lessee of any representation, warranty or condition contained in
such policies and will be primary without right of contribution from any
insurance effected by Lessor. Upon the execution of any Schedule, the Lessee
will furnish appropriate evidence of such insurance acceptable to Lessor.

Lessee will promptly repair any damaged item of Equipment unless such Equipment
has suffered a Casualty Loss. Within fifteen (15) days of a Casualty Loss,
Lessee will provide written notice of that loss to Lessor and Lessee will, at
Lessee's option, either (a) replace the item of Equipment with Like Equipment
and marketable title to the Like Equipment will automatically vest in Lessor or
(b) pay the Casualty Value and after that payment and the payment of all other
amounts due and owing with respect to that item of Equipment, Lessee's
obligation to pay further Rent for the item of Equipment will cease.

13. DEFAULT, REMEDIES AND MITIGATION.

13.1 DEFAULT. The occurrence of any one or more of the following Events of
Default constitutes a default under a Summary Equipment Schedule:

(a) Lessee's failure to pay Rent or other amounts payable by Lessee
when due if that failure continues for five (5) business days after written
notice; or

(b) Lessee's failure to perform any other term or condition of the
Schedule or the material inaccuracy of any representation or warranty made by
the Lessee in the Schedule or in any document or certificate furnished to the
Lessor hereunder if that failure or inaccuracy continues for ten (10) business
days after written notice; or

(c) An assignment by Lessee for the benefit of its creditors, the
failure by Lessee to pay its debts when due, the insolvency of Lessee, the
filing by Lessee or the filing against Lessee of any petition under any
bankruptcy or insolvency law or for the appointment of a trustee or other
officer with similar powers, the adjudication of Lessee as insolvent, the
liquidation of Lessee, or the taking of any action for the purpose of the
foregoing; or

(d) The occurrence of an Event of Default under any Schedule,
Summary Equipment Schedule or other agreement between Lessee and Lessor or its
Assignee or Secured Party.

13.2 REMEDIES. Upon the occurrence of any of the above Events of Default,
Lessor, at its option, may:

(a) enforce Lessee's penalty of the provisions of the applicable
Schedule by appropriate court action in law or in equity;

(b) recover from Lessee any damages and or expenses, including
Default Costs;

(c) with notice and demand, recover all sums due and accelerate and
recover the present value of the remaining payment stream of all Rent due under
the defaulted Schedule (discounted at the same rate of interest at which such
defaulted Schedule was discounted with a Secured Party plus any prepayment fees
charged to Lessor by the Secured Party or, if there is no Secured Party, then
discounted at 6%) together with all Rent and other amounts currently due as
liquidated damages and not as a penalty;

(d) with notice and process of law and in compliance with Lessee's
security requirements, Lessor may enter on Lessee's premises to remove and
repossess the Equipment without being liable to Lessee for damages due to the
repossession, except these resulting from Lessor's, its assignees', agents' or
representatives' negligence; and

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(e) pursue any other remedy permitted by law or equity.

The above remedies, in Lessor's discretion and to the extent permitted by
law, are cumulative and may be exercised successively or concurrently.

13.3 MITIGATION. Upon return of the Equipment pursuant to the terms of
Section 13.2, Lessor will use its best efforts in accordance with its normal
business procedures (and without obligation to give any priority to such
Equipment) to mitigate Lessor's damages as described below. EXCEPT AS SET FORTH
IN THIS SECTION, LESSEE HEREBY WAIVES ANY RIGHTS NOW OR HEREAFTER CONFERRED BY
STATUTE OR OTHERWISE WHICH MAY REQUIRE LESSOR TO MITIGATE ITS DAMAGES OR MODIFY
ANY OF LESSOR'S RIGHTS OR REMEDIES STATED HEREIN. Lessor may sell, lease or
otherwise dispose of all or any part of the Equipment at a public or private
sale for cash or credit with the privilege of purchasing the Equipment. The
proceeds from any sale, lease or other disposition of the Equipment are defined
as either:

(a) if sold or otherwise disposed of, the cash proceeds less the
Fair Market Value of the Equipment at the expiration of the Initial Term less
the Default Costs; or

(b) if leased, the present value (discounted at three percent (3%)
over the U.S. Treasury Notes of comparable maturity to the term of the release)
of the rentals for a term not to exceed the Initial Term less the Default Costs.

Any proceeds will be applied against liquidated damages and any other sums
due to Lessor from Lessee. However, Lessee is liable to Lessor for, and Lessor
may recover the amount by which the proceeds are less than the liquidated
damages and other sums due to Lessor from Lessee.

14. ADDITIONAL PROVISIONS.

14.1 BOARD ATTENDANCE. Upon invitation of Lessee, one representative of
Lessor will have the right to attend Lessee's corporate Board of Directors
meetings and Lessee will give Lessor reasonable notice in advance of any special
Board of Directors meeting, which notice will provide an agenda of the subject
matter to be discussed at such board meeting. Lessee will provide Lessor with a
certified copy of the minutes of each Board of Directors meeting within thirty
(30) days following the date of such meeting held during the term of this Master
Lease.

14.2 FINANCIAL STATEMENTS. As soon as practicable at the end of each month
(and in any event within thirty (30) days), Lessee will provide to Lessor the
same information which Lessee provides to its Board of Directors, but which will
include not less than a monthly income statement, balance sheet and statement of
cash flows prepared in accordance with generally accepted accounting principles,
consistently applied (the "Financial Statements"). As soon as practicable at the
end of each fiscal year, Lessee will provide to Lessor audited Financial
Statements setting forth in comparative form the corresponding figures for the
fiscal year (and in any event within ninety (90) days), and accompanied by an
audit report and opinion of the independent certified public accountants
selected by Lessee. Lessee will promptly furnish to Lessor any additional
Information (including, but not limited to, tax returns, income statements,
balance sheets and names of principal creditors) as Lessor reasonably believes
necessary to evaluate Lessee's continuing ability to meet financial obligations.
After the effective date of the initial registration statement covering a public
offering of Lessee's securities, the term "Financial Statements" will be deemed
to refer to only those statements required by the Securities and Exchange
Commission.

14.3 OBLIGATION TO LEASE ADDITIONAL EQUIPMENT. Upon notice to Lessee,
Lessor will not be obligated to lease any Equipment which would have a
Commencement Date after said notice if (i) Lessee is in default under this
Master Lease or any Schedule; (ii) Lessee is in default under any loan
agreement, the result of which would allow the tender or any secured party to
demand immediate payment of any material indebtedness; (iii) there is a material
adverse change in Lessee's credit standing; or (iv) Lessor

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determines (in reasonable good faith) that Lessee will be unable to perform its
obligations und er this Master Lease or any Schedule.

14.4 MERGER AND SALE PROVISIONS. Lessee will notify Lessor of any
proposed Merger at least sixty (60) days prior to the closing date. Lessor may,
in its discretion, either (i) consent to the assignment of the Master Lease and
all relevant Schedules to the successor entity, or (ii) terminate the Lease and
all relevant Schedules. If Lessor elects to consent to the assignment, Lessee
and its successor will sign the assignment documentation provided by Lessor. If
Lessor elects to terminate the Master Lease and all relevant Schedules, then
Lessee will pay Lessor all amounts then due and owing and a termination fee
equal to the present value (discounted at 6%) of the remaining Rent for the
balance of the Initial Term(s) of all Schedules, and will return the Equipment
in accordance with Section 9. Lessor hereby consents to any Merger in which the
acquiring entity has a ▇▇▇▇▇'▇ Bond Rating of BA3 or better or a commercially
acceptable equivalent measure of creditworthiness as reasonably determined by
Lessor.

14.5 ENTIRE AGREEMENT. This Master Lease and associated Schedules and
Summary Equipment Schedules supersede all other oral or written agreements or
understandings between the parties concerning the Equipment including, for
example, purchase orders. ANY AMENDMENT OF THIS MASTER LEASE OR A SCHEDULE, MAY
ONLY BE ACCOMPLISHED BY A WRITING SIGNED BY THE PARTY AGAINST WHOM THE AMENDMENT
IS SOUGHT TO BE ENFORCED.

14.6 NO WAIVER. No action taken by Lessor or Lessee will be deemed to
constitute a waive of compliance with any representation, warranty or covenant
contained in this Master Lease or a Schedule. The Waiver by Lessor or Lessee of
a breach of any provision of this Master Lease or a Schedule will not operate or
be construed as a waiver of any subsequent breach.

14.7 BINDING NATURE. Each Schedule is binding upon, and inures to the
benefit of Lessor and its assigns. LESSEE MAY NOT ASSIGN ITS RIGHTS OR
OBLIGATIONS.

14.8 SURVIVAL OF OBLIGATIONS. All agreements, obligations including, but
not limited to those arising under Section 6.2, representations and warranties
contained in this Master Lease, any Schedule, Summary Equipment Schedule or in
any document delivered in connection with those agreements are for the benefit
of Lessor and any Assignee or Secured Party and survive the execution, delivery,
expiration or termination of this Master Lease.

14.9 NOTICES. Any notice, request or other communication to either party
by the other party will be given in writing and deemed received upon the earlier
of (1) actual receipt or (2) three days after mailing if mailed postage prepaid
by regular or airmail to Lessor (to the attention of the "Comdisco Venture
Group") or Lessee, at the address set out the Schedule or (3) one day after it
is sent by courier or (4) on the same day as sent facsimile transmission,
provided that the original is sent by personal delivery or mail by the sending
party.

14.10 APPLICABLE LAW. THIS MASTER LEASE HAS BEEN, AND EACH SCHEDULE WILL
HAVE BEEN MADE, EXECUTED AND DELIVERED IN THE STATE OF ILLINOIS AND WILL BE
GOVERNED AND CONSTRUED FOR ALL PURPOSES IN ACCORDANCE WITH THE LAWS OF THE STATE
OF ILLINOIS WITHOUT GIVING EFFECT TO CONFLICT OF LAW PROVISIONS. NO RIGHTS OR
REMEDIES REFERRED TO IN ARTICLE 2A OF THE UNIFORM COMMERCIAL CODE WILL BE
CONFERRED ON LESSEE UNLESS EXPRESSLY GRANTED IN THIS MASTER LEASE OR A SCHEDULE.

14.11 SEVERABILITY. If any one or more of the provisions of this Master
Lease or any Schedule is for any reason held invalid, illegal or unenforceable,
the remaining provisions of this Master Lease and any such Schedule will be
unimpaired, and the invalid, illegal or unenforceable provision replaced by a
mutually acceptable valid legal and enforceable provision that is closest to the
original intention of the parties.

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14.12 COUNTERPARTS. This Master Lease and any Schedule may be executed in
any number of counterparts, each of which will be deemed an original, but all
such counterparts together constitute one and the same instrument. If Lessor
grants a security interest in all or any part of a Schedule, the Equipment or
sums payable thereunder, only that counterpart Schedule marked "Secured Party's
Original" can transfer Lessor's rights and all other counterparts will be marked
"Duplicate."

14.13 LICENSED PRODUCTS. Lessee will obtain no title to Licensed Products
which will at all times remain the properly of the owner of the Licensed
Products. A license from the owner may be required and it is Lessee's
responsibility to obtain any required license before the use of the Licensed
Products. Lessee agrees to treat the Licensed Products as confidential
information of the owner, to observe all copyright restrictions, and not to
reproduce or sell the Licensed Products.

14.14 SECRETARY'S CERTIFICATE. Lessee will, upon execution of this Master
Lease, provide Lessor with a secretary's certificate of incumbency and
authority. Upon the execution of each Schedule with a purchase price in excess
of $1,000,000, Lessee will provide Lessor with an opinion from Lessee's counsel
in a form acceptable to Lessor regarding the representations and warranties in
Section 8.

14.15 ELECTRONIC COMMUNICATIONS. Each of the parties may communicate with
the other by electronic means under mutually agreeable terms.

14.16 LANDLORD/MORTGAGEE WAIVER. Lessee agrees to provide Lessor with a
Landlord/Mortgagee Waiver with respect to the Equipment. Such waiver shall be
in a form satisfactory to Lessor.

14.17 EQUIPMENT PROCUREMENT CHARGES/PROGRESS PAYMENTS. Lessee hereby
agrees that Lessor shall not, by virtue of its entering into this Master Lease,
be required to remit any payments to any manufacturer or other third party until
Lessee accepts the Equipment subject to this Master Lease.

14.18 DEFINITIONS.

ADVANCE - means the amount due to Lessor by Lessee upon Lessee's execution
-------
of each Schedule.

ASSIGNEE - means an entity to whom Lessor has sold or assigned its rights
--------
as owner and Lessor of Equipment.

CASUALTY LOSS - means the irreparable loss or destruction of Equipment.
-------------

CASUALTY VALUE - means the greater of the aggregate Rent remaining to be
--------------
paid for the balance of the lease term or the Fair Market Value of the Equipment
immediately prior to the Casualty Loss. However, if a Casualty Value Table is
attached to the relevant Schedule its terms will control.

COMMENCEMENT DATE - is defined in each Schedule.
-----------------

DEFAULT COSTS - means reasonable attorney's fees and remarketing costs
-------------
resulting from a Lessee default or Lessor's enforcement of its remedies.

DELIVERY DATE - means date of delivery of Inventory Equipment to Lessee's
-------------
address.

EQUIPMENT - means the property described on a Summary Equipment Schedule
---------
and any replacement for that property required or permitted by this Master Lease
or a Schedule.

EVENT OF DEFAULT - means the events described in Subsection 13.1.
----------------

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FAIR MARKET VALUE - means the aggregate amount which would be obtainable in
-----------------
an arm's-length transaction between an informed and willing buyer/user and an
informed and willing seller under no compulsion to sell.

INITIAL TERM - means the period of time beginning on the first day of the
------------
first full Rent Interval following the Commencement Date for all terms of
Equipment and continuing for the number of Rent Intervals indicated on a
Schedule.

INTERIM RENT - means the pro rata portion of Rent due for the period from
------------
the Commencement Date through but not including the first day of the first full
Rent Interval included in the Initial Term.

LATE CHARGE - means the lesser of five percent (5%) of the payment due or
-----------
the maximum amount permitted by the law of the state where the Equipment is
located.

LICENSED PRODUCTS - means any software or other licensed products attached
-----------------
to the Equipment.

LIKE EQUIPMENT - means replacement Equipment which is lien free and of the
--------------
same model, type, configuration and manufacture as Equipment.

MERGER - means any consolidation or merger of the Lessee with or into any
------
other corporation or entity, any sale or conveyance of all or substantially all
of the assets or stock of the Lessee by or to any other person or entity in
which Lessee is not the surviving entity.

NOTICE PERIOD - means not less than ninety (90) days no more than twelve
-------------
(12) months prior to the expiration of the lease term.

OWNER - means the owner of Equipment.
-----

RENT - means the rent Lessee will pay for each item of Equipment expressed
----
in a Summary Equipment Schedule either as a specific amount or an amount equal
to the amount which Lessor pays for an item of Equipment multiplied by a lease
rate factor plus all other amounts due to Lessor under this Master Lease or a
Schedule.

RENT INTERVAL - means a full calendar month or quarter as indicated on a
-------------
Schedule.

SCHEDULE - means either an Equipment Schedule or a Licensed Products
--------
Schedule which incorporates all of the terms and conditions of this Master
Lease.

SECURED PARTY - means an entity to whom Lessor has granted a security
-------------
interest for the purpose of securing a loan.

SUMMARY EQUIPMENT SCHEDULE - means a certificate provided by Lessor
--------------------------
summarizing all of the Equipment for which Lessor has received Lessee-approved
vendor invoices, purchase documents and/or evidence of delivery during a
calendar quarter which will incorporate all of the terms and conditions of the
related Schedule and this Master Lease and will constitute a separate lease for
the Equipment leased thereunder.

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IN WITNESS WHEREOF, the parties hereto have executed this Master Lease on or as
of the day and year first above written.

FLYCAST COMMUNICATIONS CORPORATION COMDISCO, INC.,
as Lessee as Lessor

By: /s/ By: /s/
______________________________ _____________________________

Title:___________________________ Title:__________________________

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ADDENDUM TO THE
MASTER LEASE AGREEMENT DATED AS OF DECEMBER 30,1997
BETWEEN FLYCAST COMMUNICATIONS CORPORATION, AS LESSEE
AND COMDISCO, INC., AS LESSOR

The undersigned hereby agree that the terms and conditions of the above-
referenced Master Lease are hereby modified and amended as follows:

1) 5.1., "TITLE"
-----

Insert the words "or such Assignee or such Secured Party or Owner." to the
end of the last sentence of the paragraph.

2) 7.1., "CARE, USE AND MAINTENANCE"
-------------------------

Insert the word "reasonable" after the word "any" in the third sentence and
delete the phrase "for the manufacturer to bring the Equipment to then
current release, revision and engineering change levels, and" from the same
sentence.

3) 8., "REPRESENTATIONS AND WARRANTIES OF LESSEE"
----------------------------------------

Subparagraph (b), insert the words "to Lessee's knowledge" before the word
"contravene" in the fifth line of the first sentence and insert the words
"in any material aspects" after the word "contravene" in the same line.

Subparagraph (g), insert the words "to the best of Lessee's knowledge" at
the beginning of the sentence.

4) 11., "INDEMNITY"
---------

Insert the words ", reckless or intentional" after the word "negligent" in
the third line of the second sentence; and change the word "such" to "any"
in the same line, before the word "indemnified".

Add the following language to the end of the section:

IN NO EVENT WILL LESSOR OR LESSEE BE LIABLE FOR ANY SPECIAL, INCIDENTAL
DAMAGES OR OTHER CONSEQUENTIAL DAMAGES, EVEN IF SUCH PARTY HAS BEEN ADVISED
OF THE POSSIBILITY OF SUCH DAMAGES.

(5) 13.1., "DEFAULTS"
--------

Subparagraph (b), in the last line, change the words "ten (10)" to "twenty
(20)". Subparagraph (d), insert the following phrase at the end of the
sentence:

", if such Event of Default continues uncured during the cure period
provided for such occurrence in the applicable Schedule, Summary Equipment
Schedule or other agreement."

6) 13.2., "REMEDIES"
--------

Subparagraph (d), insert the phrase "reckless or willful misconduct" after
the word "negligence" in the last line.

7) 14.1., "BOARD ATTENDANCE"
----------------

In the first sentence, insert the words "at least one of" after the word
"attend" on in the first line and insert the word "annually" after the word
"meetings" in the second line. In the third line, replace "any special"
with "such"; after "meeting" delete the rest of the sentence.

Delete the last sentence of the existing paragraph in its entirety.

Insert the following sentence at the end thereof:

"Notwithstanding anything to the contrary contained herein, Lessor's right
to attend Board of Directors meetings shall cease upon the effective date
of Lessee's registration statement in connection with an initial public
offering of its securities."

8) 14.2., "FINANCIAL STATEMENTS"
--------------------

In the first sentence, change the words "thirty (30)" to "forty-five (45)".
In the second sentence, change the words "ninety (90)" to "one hundred
twenty (120)". In the last sentence of the section, change the first word
"After" to the phrase "This obligation shall terminate upon the" and delete
the last portion of the sentence which reads "the term "Financial
Statements" shall be deemed to refer to only those statements required by
the Securities and Exchange Commission."

-2-

9) 14.4., "MERGER AND SALE PROVISIONS"
--------------------------

In the first sentence, change the words "sixty (60)" to "twenty (20)". In
the last sentence, insert the phrase "and assignment of the Master Lease"
after the word "Merger", insert the phrase ", a measure of credit
worthiness at least as

good as that of Lessee, as reasonably determined by Lessor" after the word
"better" in the second line and change the word "acquiring" to the word
"successor" in the same line.

10) 14.8., "NO WAIVER"
---------

Insert the phrase "(other than a written waiver)" after the word "Lessee"
in the first line of the first sentence.

11) 14.9., "NOTICES"
-------

Insert the phrase "a facsimile confirmation is received by the sending
party and" after the words "provided that" in the last full line of the
section.

12) 14.10., "APPLICABLE LAW"
--------------

Change both occurrences of the word "ILLINOIS" to "CALIFORNIA" in this
paragraph. In the second section of the paragraph, change "ARTICLE 2 OF
THE UNIFORM COMMERCIAL CODE" to "CALIFORNIA UNIFORM
COMMERCIAL CODE SECTIONS 10508-10522".

13) 14.14., "SECRETARY'S CERTIFICATE"
-----------------------

Delete the last sentence of this section.

14) 14.18., "DEFINITIONS"
-----------

LIKE EQUIPMENT - insert the phrase "or other property reasonably acceptable
--------------
to Lessor" at the end of the definition.

FLYCAST COMMUNICATIONS CORPORATION COMDISCO, INC.
AS LESSEE AS LESSOR

By:_______________________ By:______________________
__________________________
Title:____________________ Title:___________________
__________________________
Date:_____________________ Date:____________________

-3-

EQUIPMENT SCHEDULE VL-2
DATED AS OF DECEMBER 30,1997
TO MASTER LEASE AGREEMENT
DATED AS OF DECEMBER 30,1997 (THE "MASTER LEASE")

LESSEE: FLYCAST COMMUNICATIONS LESSOR: COMDISCO, INC.
CORPORATION

ADMIN. CONTACT/PHONE NO.: ADDRESS FOR ALL NOTICES:
------------------------ -----------------------
_____________________ ▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇
Phone: _______________________ ▇▇▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ ▇▇▇▇▇
Fax: _________________________ Attn.: Venture Group

Address for Notices:
-------------------
▇▇▇ ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇
▇▇▇ ▇▇▇▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇

Central Billing Location: Rent Interval: Monthly
------------------------ -------------
same as above

Attn.:

Lessee Reference No.: ______________
(24 digits maximum)

Location of Equipment: Initial Term: 42 months
--------------------- ------------
same as above (Number of Rent Intervals)

Lease Rate Factor: 2.720%
Attn.: -----------------

EQUIPMENT (as defined below): Advance: $3,264.00
-------

Software and tenant improvements specifically approved by Lessor, which shall be
delivered to and accepted by Lessee during the period December 30, 1997 through
December 30, 1998 ("Equipment Delivery Period"), for which Lessor receives
vendor invoices approved for payment, up to an aggregate purchase price of
$120,000.00 ("Commitment Amount"). Equipment shall exclude custom use
equipment, leasehold improvements, installation costs and delivery costs,
rolling stock, special tooling, hand held items, molds and fungible items.

1. EQUIPMENT PURCHASE

This Schedule contemplates Lessor's acquisition of Equipment for lease to
Lessee, either by one of the first three categories listed below or by providing
Lessee with Equipment from the fourth category, in an aggregate value up to the
Commitment Amount referred to on the face of this Schedule. If the Equipment
acquired is of category (i), (ii), (iii) below, the effectiveness of this
Schedule as it relates to those items of Equipment is contingent upon Lessee's
acknowledgment at the time Lessor acquires the Equipment that Lessee has either
received or approved the relevant purchase documentation between vendor and
Lessor for that Equipment.

(i) NEW ON-ORDER EQUIPMENT. Lessor will purchase new Equipment which is
obtained from a vendor by Lessee for its use subject to Lessor's
prior approval of the Equipment.

(ii) SALE-LEASEBACK EQUIPMENT. Any in-place Equipment installed at
Lessee's site and to which Lessee has clear title and ownership may
be considered by Lessor for inclusion under this Lease (the Sale-
Leaseback Transaction"). Any request for a Sale-Leaseback
Transaction must be submitted to Lessor in writing (along with
accompanying evidence of Lessee's Equipment ownership satisfactory
to Lessor for all Equipment submitted). Further, any sale-leaseback
Equipment will be placed on lease subject to: (1) Lessor prior
approval of the Equipment; and (2) if approved, at Lessor's actual
net appraised Equipment value.

Lessee represents that it has paid all California sales tax due on the cost of
that portion of Equipment to be installed in California and agrees to provide
evidence of such payment to Lessor, if specifically requested. As a result of
the election, Lessor agrees that it will not invoice Lessee for use tax on the
monthly rental rate. Lessee understands that this is an irrevocable election to
measure the tax by the Equipment cost and cannot be changed except prior to
installation of the Equipment.

(iii) USED ON-ORDER EQUIPMENT. Lessor will purchase used Equipment which
is obtained from a third party by Lessee for its use subject to
Lessor's prior approval of the Equipment and at Lessor's appraised
value for such used Equipment.

(iv) 800 NUMBER EQUIPMENT. Upon Lessee's use of Comdisco's 1-800 Direct
Service, Lessor will purchase new or used Equipment from a third
party or Lessor will supply new or used Equipment from its inventory
for use by Lessee at rates provided by Lessor.

2. COMMENCEMENT DATE

The Commencement Date for each item of new on-order or used on-order
Equipment will be the install date as confirmed in writing by Lessee as set
forth on the vendor invoice of which a facsimile transmission will constitute an
original document. The Commencement Date for saIe-Ieaseback Equipment shall be
the date Lessor tenders the purchase price. The Commencement Date for 800
Number Equipment shall be fifteen (15) days from the ship date, such ship date
to be set forth on the vendor invoice or if unavailable on the vendor invoice
the ship date will be determined by Lessor upon other supporting shipping
documentation. Lessor will summarize all approved invoices, purchase
documentation and evidence of delivery, as applicable, received in the same
calendar quarter into a Summary Equipment Schedule in the form attached to this
Schedule as Exhibit 1, and the Initial Term will begin the first day of the
calendar quarter thereafter. Each Summary Equipment Schedule will contain the
Equipment location, description, serial number(s) and cost and will incorporate
the terms and conditions of the Master Lease and this Schedule and will
constitute a separate lease.

-2-

3. MISCELLANEOUS

In consideration of Lessor financing software and tenant improvements
hereunder, Lessee agrees in addition to its last Monthly Rent Payment to remit
to Lessor an amount equal to 15% of Lessor's aggregate cost of software and
tenant improvements provided hereunder.

4. OPTION AMOUNT

So long as no Event of Default shall have occurred and is continuing and
upon Lessee's written request and upon payment of an additional Advance in the
amount of $4,896.00, subject to final review by Lessor, at any time during the
Equipment Delivery Period, an additional amount of $180,000.00 shall be
available to Lessee under the same terms and conditions as stated herein. Such
additional amount shall thereafter be considered an addition to the Commitment
Amount referenced above.

5. SPECIAL TERMS

The terms and conditions of the Lease as they pertain to this Schedule are
hereby modified and amended as follows:

a) Section 9, Delivery and Return of Equipment
-------------------------------------------

Delete second, third and fourth sentences in their entirety.

Master Lease: This Schedule is issued pursuant to the Lease identified on page 1
of this Schedule. All of the terms and conditions of the Lease are incorporated
in and made a part of this Schedule as if they were expressly set forth in this
Schedule. The parties hereby reaffirm all of the terms and conditions of the
Lease (including, without limitation, the representations and warranties set
forth in Section 8) except as modified herein by this Schedule. This Schedule
may not be amended or rescinded except by a writing signed by both parties.

FLYCAST COMMUNICATIONS COMDISCO, INC.
CORPORATION AS LESSOR
AS LESSEE

By:________________________ By:________________________

Title:_____________________ Title:_____________________

Date:______________________ Date:______________________

-3-

EXHIBIT 1

SUMMARY EQUIPMENT SCHEDULE
--------------------------

This Summary Equipment Schedule dated XXXX is executed pursuant to
Equipment Schedule No. X to the Master Lease Agreement dated XXXX between
Comdisco, Inc. ("Lessor") and XXXX ("Lessee"). All of the terms, conditions,
representations and warranties of the Master Lease Agreement and Equipment
Schedule No. X are incorporated herein and made a part hereof, and this Summary
Equipment Schedule constitutes a Schedule for the Equipment on the attached
invoices.

1. For Period Beginning: And Ending:
-------------------- ----------

2. Initial Term Starts on: Initial Term:
---------------------- ------------
(Number of Rent Intervals)

3. Total Summary Equipment Cost:
----------------------------

4. Lease Rate Factor:
-----------------

5. Rent:
----

6. Acceptance Doc Type:
-------------------

EQUIPMENT SCHEDULE VL-1
DATED AS OF DECEMBER 30, 1997
TO MASTER LEASE AGREEMENT
DATED AS OF DECEMBER 30, 1997 (THE "MASTER LEASE")

LESSEE: FLYCAST COMMUNICATIONS LESSOR: COMDISCO, INC.
CORPORATION

Admin. Contact/Phone No.: ADDRESS FOR ALL NOTICES:
------------------------ -----------------------
__________________ ▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇
▇▇▇▇▇:______________________ ▇▇▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ ▇▇▇▇▇
Fax:________________________ Attn.: Venture Group

Address for Notices:
-------------------
▇▇▇ ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇
▇▇▇ ▇▇▇▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇

Central Billing Location: Rent Interval: Monthly
------------------------ -------------
same as above

Attn.:

Lessee Reference No.: ______________
(24 digits maximum)

Location of Equipment: Initial Term: 42 months
--------------------- ------------
same as above (Number of Rent Intervals)

Attn.: Lease Rate Factor: 2.720%
-----------------

EQUIPMENT (as defined below): Advance: $7,616.00
-------

Equipment specifically approved by Lessor, which shall be delivered to and
accepted by Lessee during the period December 30, 1997 through December 30, 1998
("Equipment Delivery Period"), for which Lessor receives vendor invoices
approved for payment, up to an aggregate purchase price of $280,000.00
("Commitment Amount"). Equipment shall exclude custom use equipment, leasehold
improvements,

installation costs and delivery costs, rolling stock, special tooling, "stand-
alone" software, application software bundled into computer hardware, hand held
items, molds and fungible items.

-2-

1. EQUIPMENT PURCHASE

(i) NEW ON-ORDER EQUIPMENT. Lessor will purchase new Equipment which is
obtained from a vendor by Lessee for its use subject to Lessor's
prior approval of the Equipment.

2. COMMENCEMENT DATE

The Commencement Date for each item of new on-order or used on-order
Equipment will be the install date as confirmed in writing by Lessee as set
forth on the vendor invoice of which a facsimile transmission will constitute an
original document. The Commencement Date for sale-leaseback Equipment shall be
the date Lessor tenders the purchase price. The Commencement Date for 800
Number Equipment shall be fifteen (15) days from the ship date, such ship date
to be set forth on the vendor invoice or if unavailable on the vendor invoice
the ship date will be determined by Lessor upon other supporting shipping
documentation. Lessor will summarize all approved invoices, purchase
documentation and evidence of delivery, as applicable, received in the same
calendar quarter into a Summary Equipment Schedule in the form attached to this
Schedule as Exhibit 1, and the Initial Term will begin the first day of the
calendar quarter thereafter. Each Summary Equipment Schedule will contain the
Equipment location, description, serial

-3-

number(s) and cost and will incorporate the terms and conditions of the Master
Lease and this Schedule and will constitute a separate lease.

3. OPTION TO EXTEND

So long as no Event of Default has occurred and is continuing hereunder,
and upon written notice no earlier than twelve (12) months and no later than
ninety (90) days prior to the expiration of the Initial Term of a Summary
Equipment Schedule, Lessee will have the right to extend the Initial Term of
such Summary Equipment Schedule for a period of one (1) year. In such event,
the rent to be paid during said extended period shall be mutually agreed upon
and if the parties cannot mutually agree, then the Summary Equipment Schedule
shall continue in full force and effect pursuant to the existing terms and
conditions until terminated in accordance with its terms. The Summary Equipment
Schedule will continue in effect following said extended period until terminated
by either party upon not less than ninety (90) days prior written notice, which
notice shall be effective as of the date of receipt.

4. PURCHASE OPTION

So long as no Event of Default has occurred and is continuing hereunder,
and upon written notice no earlier than twelve (12) months and no later than
ninety (90) days prior to the expiration of the Initial Term or the extended
term of the applicable Summary Equipment Schedule, Lessee will have the option
at the expiration of the Initial Term of the Summary Equipment Schedule to
purchase all, but not less than all, of the Equipment listed therein for a
purchase price not to exceed 15% of the Equipment cost and upon terms and
conditions to be mutually agreed upon by the parties following Lessee's written
notice, plus any taxes applicable at time of purchase. Said purchase price
shall be paid to Lessor at least thirty (30) days before the expiration date of
the Initial Term or extended term. Title to the Equipment shall automatically
pass to Lessee upon payment in full of the purchase price but, in no event,
earlier than the expiration of the fixed Initial Term or extended term, if
applicable. If the parties are unable to agree on the purchase price or the
terms and conditions with respect to said purchase, then the Summary Equipment
Schedule with respect to this Equipment shall remain in full force and effect.
Notwithstanding the exercise by Lessee of this option and payment of the
purchase price, until all obligations under the applicable Summary Equipment
Schedule have been fulfilled, it is agreed and understood that Lessor shall
retain a purchase money security interest in the Equipment listed therein and
the Summary Equipment Schedule shall constitute a Security Agreement under the
Uniform Commercial Code of the state in which the Equipment is located.

5. OPTION AMOUNT

So long as no Event of Default shall have occurred and is continuing and
upon Lessee's written request and upon payment of an additional Advance in the
amount of $11,424.00, subject to final review by Lessor, at any time during the
Equipment Delivery Period, an additional amount of $420,000.00 shall be
available to Lessee under the same terms and conditions as stated herein. Such
additional amount shall thereafter be considered an addition to the Commitment
Amount referenced above.

6. EQUITY CONSIDERATION

In consideration of the Lessor executing and delivering such Leases, Lessee
has allowed Lessor the right to purchase 187,970 shares of Lessee's Series B
Preferred Stock at $1.33 per share for an aggregate purchase price of
$250,000.10.
-4-

7. TECHNOLOGY EXCHANGE OPTION

If Lessee is not in default, and there is no material adverse change in
Lessee's credit, on or after the expiration of the 12th month of any Summary
Equipment Schedule, Lessee shall have the option to replace any of the Equipment
subject to such summary Equipment Schedule with new technology equipment ("New
Technology Equipment") utilizing the following guidelines:

A. Equipment being replaced with New Technology Equipment shall have an
aggregate original cost equal to or greater than $20,000 and be comprised of
full configurations of equipment.

B. This technology Exchange Option shall be limited to a maximum in the
aggregate of fifty percent (50%) of the original equipment cost and shall not
apply to software.

C. The cost of the New Technology Equipment must be equal to or greater than
the original equipment cost of the replaced equipment, but in no event shall
exceed 150% of the original equipment cost.

D. The remaining lease payments applicable to the equipment being replaced by
the New Technology Equipment will be discounted to present value at 6%.

The wholesale market value of the equipment being replaced will be established
by Comdisco based upon then current market conditions. Upon the return of the
replaced equipment, the wholesale price will be deducted from the present value
of the remaining rentals and the differential will be added to the cost of the
New Technology Equipment in calculating the new rental. The lease for the New
Technology Equipment will contain terms and conditions substantially similar to
those for the replaced equipment and will have an Initial Term not less than the
balance of the remaining Initial Term for the replaced equipment.

8. SPECIAL TERMS

The terms and conditions of the Lease as they pertain to this Schedule are
hereby modified and amended as follows:

a) 14.16. Landlord/Mortgagee Waiver: Delete this section in its entirety.

FLYCAST COMMUNICATIONS
CORPORATION
AS LESSEE

By: /s/
____________________________

Title:_________________________

Date:__________________________

COMDISCO, INC.
AS LESSOR

-5-

By:____________________________

Title:_________________________

Date:__________________________

-6-

EXHIBIT 1

SUMMARY EQUIPMENT SCHEDULE
--------------------------

1. For Period Beginning: And Ending:
-------------------- ----------

2. Initial Term Starts on: Initial Term:
---------------------- ------------
(Number of Rent Intervals)

3. Total Summary Equipment Cost:
----------------------------

4. Lease Rate Factor:
-----------------

5. Rent:
----

6. Acceptance Doc Type:
-------------------

-7-

MASTER LEASE AGREEMENT

MASTER LEASE AGREEMENT (the "Master Lease") dated December 30, 1997 by and
between COMDISCO, INC. ("Lessor") and FlyCast Communications Corporation
("Lessee").

IN CONSIDERATION of the mutual agreements described below, the parties
agree as follows (all capitalized terms are defined in Section 14.18):

1. PROPERTY LEASED.

Lessor leases to Lessee all of the Equipment described on each Summary
Equipment Schedule. In the event of a conflict, the terms of the applicable
Schedule prevail over this Master Lease.

2. TERM.

On the Commencement Date, Lessee will be deemed to accept the Equipment,
will be bound to its rental obligations for each item of Equipment and the term
of a Summary Equipment Schedule will begin and continue through the Initial Term
and thereafter until terminated by either party upon prior written notice
received during the Notice Period. No termination may be effective prior to the
expiration of the Initial Term.

3. RENT AND PAYMENT.

Rent is due and payable in advance on the first day of each Rent Interval
at the address specified in Lessor's invoice. Interim Rent is due and payable
when invoiced. If any payment is not made when due, Lessee will pay a Late
Charge on the overdue amount. Upon Lessee's execution of each Schedule, Lessee
will pay Lessor the Advance specified on the Schedule. The Advance will be
credited towards the final Rent payment is Lessee is not then in default. No
interest will be paid on the Advance.

4. SELECTION; WARRANTY AND DISCLAIMER OF WARRANTIES.

4.1 SELECTION. Lessee acknowledges that it has selected the Equipment and
disclaims any reliance upon statements made by the Lessor, other than as set
forth in the Schedule.

5. TITLE; RELOCATION OR SUBLEASE; AND ASSIGNMENT.

No relocation or sublease will relieve Lessee from any of its obligations
under this Master Lease and the relevant Schedule.

(c) Subject to and without impairment of Lessee's leasehold rights in
the Equipment, Lessee holds the Equipment for the Secured Party to the extent of
the Secured Party's rights in that Equipment.

6. NET LEASE; TAXES AND FEES.

6.1 NET LEASE. Each Summary Equipment Schedule constitutes a net lease.
Lessee's obligation to pay Rent and all other amounts due hereunder is absolute
and unconditional and is not subject to any abatement, reduction, set-off,
defense, counterclaim, interruption, deferment or recoupment for any reason
whatsoever.

-2-

and pay all such property taxes due. Lessee will reimburse Lessor for property
taxes within thirty (30) days of receipt of an invoice.

7. CARE, USE AND MAINTENANCE; INSPECTION BY LESSOR.

8. REPRESENTATIONS AND WARRANTIES OF LESSEE. Lessee hereby represents,
warrants and covenants that with respect to the Master Lease and each Schedule
executed hereunder:

(d) The Equipment is personal property and when subjected to use by
the Lessee will not be or become fixtures under applicable law.

-3-

9. DELIVERY AND RETURN OF EQUIPMENT.

10. LABELING.

11. INDEMNITY.

-4-

12. RISK OF LOSS.

Effective upon delivery and until the Equipment is returned, Lessee relieves
Lessor of responsibility for all risks of physical damage to or loss or
destruction of the Equipment. Lessee will carry casualty insurance for each
item of Equipment in an amount not less than the Casualty Value. All policies
for such insurance will name the Lessor and any Secured Party as additional
insured and as loss payee and will provide for at least thirty (30) days prior
written notice to the Lessor of cancellation or expiration, and will insure
Lessors interests regardless of any breach or violation by Lessee of any
representation, warranty or condition contained in such policies and will be
primary without right of contribution from any insurance effected by Lessor.
Upon the execution of any Schedule, the Lessee will furnish appropriate evidence
of such insurance acceptable to Lessor.

13. DEFAULT, REMEDIES AND MITIGATION.

13.1 DEFAULT. The occurrence of any one or more of the following Events
of Default constitutes a default under a Summary Equipment Schedule:

(a) Lessee's failure to pay Rent or other amounts payable by Lessee
when due if that failure continues for five (5) business days after written
notice; or

(d) The occurrence of an Event of Default under any Schedule, Summary
Equipment Schedule or other agreement between Lessee and Lessor or its Assignee
or Secured Party.

13.2 REMEDIES. Upon the occurrence of any of the above Events of Default,
Lessor, at its option, may:

(a) enforce Lessee's penalty of the provisions of the applicable
Schedule by appropriate court action in law or in equity;

(b) recover from Lessee any damages and or expenses, including
Default Costs;

(c) with notice and demand, recover all sums due and accelerate and
recover the present value of the remaining payment stream of all Rent due under
the defaulted Schedule (discounted

-5-

at the same rate of interest at which such defaulted Schedule was discounted
with a Secured Party plus any prepayment fees charged to Lessor by the Secured
Party or, if there is no Secured Party, then discounted at 6%) together with all
Rent and other amounts currently due as liquidated damages and not as a penalty;

(e) pursue any other remedy permitted by law or equity.

The above remedies, in Lessor's discretion and to the extent permitted by
law, are cumulative and may be exercised successively or concurrently.

(a) if sold or otherwise disposed of, the cash proceeds less the Fair
Market Value of the Equipment at the expiration of the Initial Term less the
Default Costs; or

14. ADDITIONAL PROVISIONS.

-6-

an audit report and opinion of the independent certified public accountants
selected by Lessee. Lessee will promptly furnish to Lessor any additional
Information (including, but not limited to, tax returns, income statements,
balance sheets and names of principal creditors) as Lessor reasonably believes
necessary to evaluate Lessee's continuing ability to meet financial obligations.
After the effective date of the initial registration statement covering a public
offering of Lessee's securities, the term "Financial Statements" will be deemed
to refer to only those statements required by the Securities and Exchange
Commission.