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                                                                   EXHIBIT 10.4

                            AMB PROPERTY CORPORATION

                 DIVIDEND REINVESTMENT AND DIRECT PURCHASE PLAN

                                  JULY 9, 1999


1.    PURPOSE AND ADMINISTRATION

            AMB Property Corporation, a Maryland corporation (the "Company"),
has adopted three plans for the direct purchase of shares of the Company's
common stock, par value $.01 per share (the "Common Stock"): (i) the Dividend
Reinvestment Program (the "DRIP"); (ii) the Discount Stock Purchase Plan (the
"DSPP"); and (iii) the Waiver Discount Plan (the "WDP"). The DRIP, DSPP and WDP
are collectively referred to as the "Plan." The purpose of the Plan is to
provide existing stockholders of the Company with an opportunity to invest
automatically the cash dividends paid upon shares of the Company's Common Stock
held by them, as well as to permit existing and prospective stockholders to make
voluntary cash purchases of such Common Stock. BankBoston N.A as agent, or such
successor plan administrator as we may designate (the "Agent"), will administer
the Plan. EquiServe L.L.C., a registered transfer agent, will provide certain
administrative support to the Agent.

2.    PARTICIPATION

            Any existing holder of shares of Common Stock with any of such
shares registered in his or her name on the records of the Agent and, with
respect to the DSPP and WDP, certain other persons as described below, may
enroll in the Plan (any such person so enrolled in the Plan is referred to
herein as a "Participant"). Beneficial owners of shares of Common Stock
registered in the name of another person or entity must make arrangements for
that person or entity to handle investment or reinvestment with respect to
dividends received upon such shares, or must arrange to have such shares
registered in the beneficial owner's name in order to participate.

            If a Participant holds shares registered in the name of another
person, a Broker/Nominee Form ("B/N Form") provides the sole means whereby a
broker, bank or other nominee holding shares on a Participant's behalf may
request an Optional Cash Purchase for the Participant. In such case, the broker,
bank or other nominee must use a B/N Form for transmitting Optional Cash
Purchases on the Participant's behalf. A B/N Form must be delivered to the Agent
each time that such broker, bank or other nominee transmits Optional Cash
Purchases on the Participant's behalf. A Participant may request a B/N Form from
the Agent in writing or by telephone.

            To enroll in the Plan, a prospective Participant must complete and
sign an enrollment form, substantially in the form attached hereto as Exhibit
A-1 or Exhibit A-2

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(collectively the "Enrollment Form") and return it to the Agent and, if
applicable, a Request for Waiver, substantially in the form attached hereto as
Exhibit B (the "Request for Waiver"), and return it to the Company. If the
shares of Common Stock are registered in the more than one name (such as joint
tenants, trustees, etc.), all registered holders must sign an Enrollment Form
and, if applicable, the Request for Waiver.

             A prospective Participant may join the Plan at any time.
Participation in the DRIP will begin with the first dividend payment after an
Enrollment Form, designating the reinvestment of dividends, is received by the
Agent, provided there is sufficient time for processing prior to the next
dividend record date. Participation in the DSPP will begin concurrently with the
first DSPP Investment Date after an Enrollment Form and the DSPP Payment (as
defined below) are received by the Agent, provided the payment is received two
full business days prior to the next DSPP Investment Date. Participation in the
WDP will begin upon commencement of the first Investment Period (as defined
below) after the Request for Waiver, approved by the Company, and the WDP
Payment (as defined below) are received by the Agent, provided the payment is
received two full business days prior to the next Investment Period.

            By selecting the "Partial Reinvestment" option on the Enrollment
Form, stockholders may elect to receive cash dividends on a specified number of
their shares, and reinvest the dividends on the balance of such shares. A
Participant may change the dividend reinvestment option at any time by
submitting a newly executed Enrollment Form to the Agent or by writing to the
Agent. Enrollment Forms may be obtained by contacting the Agent at the address
set forth in Section 22. Any change in the number of shares with respect to
which the Agent is authorized to reinvest dividends must be received by the
Agent prior to the record date for a dividend to permit the new number of shares
to apply to that dividend.

3.    DIVIDEND REINVESTMENT

            Purchases of shares of Common Stock with reinvested dividends shall
occur on the dividend payment date or on the actual date of purchase if the
Company directs the Agent to extend the period used to purchase shares in the
open market or in privately negotiated transactions for up to an additional
trading 15 days after the applicable dividend payment date. Shares of Common
Stock purchased with such reinvested dividends shall be, at the Company's
option, either from (i) authorized but unissued shares of Common Stock or (ii)
shares of Common Stock purchased by the Agent in open market or privately
negotiated transactions. In either case, such shares of Common Stock will be
sold to the Participant at a price per share determined in accordance with
Section 5 hereof.

4.    OPTIONAL CASH PURCHASES

            A voluntary cash purchase may be made under either the DSPP or WDP
(the "Optional Cash Purchase") at the time a Participant enrolls in the Plan,
and thereafter from time to time as set forth below. Participants may make
Optional Cash Purchases under the

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DSPP by delivering a check or money order payable to AMB Investment Plan to the
Agent at the address set forth herein. Participants may make Optional Cash
Purchases under the WDP by transmitting immediately available funds to the Agent
to the account referenced on the Request for Waiver. Participants should send
all inquiries regarding other forms of payments and all other written inquiries
directly to the Agent at its address set forth in Section 22.

      A.    Direct Share Purchase Plan.

            Any Participant may purchase additional shares of Common Stock under
the DSPP by delivering to the Agent a check or money order in U.S. currency made
payable to AMB Investment Plan at the address set forth in Section 22. Wire
transfers are not permitted for purchases under the DSPP. Under the DSPP, the
purchase of shares of Common Stock by a Participant will occur on the next DSPP
Investment Date following the date on which the Agent receives the DSPP Payment;
provided, however, that if any DSPP Payment is received less than two full
business days before the second DSPP Investment Date following the date the
payment is received by the Agent, such DSPP Payment will be used to purchase
shares of Common Stock on the next DSPP Investment Date following the date on
which the Agent receives the DSPP Payment if the Agent determines, in its sole
discretion, that insufficient time exists to process the DSPP Payment prior to
the next DSPP Investment Date. The aggregate amount of any DSPP Payment of a
Participant used to purchase shares of Common Stock during any calendar month
shall not be less than $500 nor more than $5,000. Shares of Common Stock
purchased under the DSPP shall be, at the Company's option, either from (i)
authorized but unissued shares of Common Stock or (ii) shares of Common Stock
purchased by the Agent in open market or privately negotiated transactions. In
either case, such shares of Common Stock will be sold to the Participant at a
price per share determined in accordance with Section 5.

      B.    Waiver Discount Plan.

            Any Participant may purchase additional shares of Common Stock under
the WDP by transferring immediately available funds to the account referenced in
the Request for Waiver. The Agent must also receive written approval from the
Company of the Request for Waiver at least one full business day before the next
Investment Period. Under the WDP, a Participant shall purchase the maximum
number of shares of Common Stock that may be purchased on each trading day
during the applicable Investment Period (as defined below) with 1/12th of the
WDP Payment at a price per share equal to the average of the average high and
low price per share on that particular trading day during the applicable
Investment Period as reported by the New York Stock Exchange or, if the Common
Stock is not then listed on the New York Stock Exchange, any other securities
exchange or national quotation service on which the Common Stock is then traded
or listed for quotation, less a discount of up to 5% in the case of purchases of
previously unissued shares of Common Stock, subject to any applicable Threshold
Price (as defined below) established pursuant to Section 4.C below (the
"Investment Period Average Purchase Price"). "Investment Period" means the
period of twelve (12) consecutive trading days

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during any calendar month commencing on a date determined at the sole discretion
of the Company. Under the WDP, the purchase of shares of Common Stock by a
Participant will occur on each trading day during the Investment Period on which
shares are traded on the NYSE and, if applicable, on which the average of the
high and low sales price per share, as reported on the NYSE, exceeds the
applicable Threshold Price. Under the WDP, a Participant will acquire, on each
such trading day, all rights of ownership with respect to the shares of Common
Stock purchased on such day, including without limitation, the right to dispose
of or vote such shares. The WDP Payment must be received by the Agent not less
than two full business days before the commencement of the Investment Period;
provided, however, that if any WDP Payment is received less than two full
business days before the commencement of an Investment Period, such WDP Payment
will be used to purchase shares of Common Stock on the second Investment Period
following the date on which the Agent receives the WDP Payment if the Agent
determines, in its sole discretion, that insufficient time exists to process the
WDP Payment prior to commencement of the next Investment Period. The aggregate
amount of any WDP Payment of a Participant used to purchase shares of Common
Stock during any calendar month shall not be less than $5,000. Shares of Common
Stock purchased under the WDP shall be, at the Company's option, either from (i)
authorized and unissued shares of Common Stock or (ii) shares of Common Stock
purchased by the Agent in open market or privately negotiated transactions. In
either case, such shares of Common Stock will be sold to the Participant at a
price per share determined in accordance with Section 5.

      C.    Threshold Pricing.

         The Company may elect to establish for any Investment Period a minimum
threshold price (a "Threshold Price") applicable to Optional Cash Purchases made
under the WDP with respect to the purchase of newly issued shares of Common
Stock not later than three business days prior to the first day of the
applicable Investment Period. The Threshold Price, if any, shall be determined
by the Company in its sole discretion after reviewing the current market
conditions and shall be the per share price that the average of the high and low
prices of the Common Stock as reported on the New York Stock Exchange must equal
or exceed for each trading day of the relevant Investment Period. In the event
that (i) the average per share sale price does not equal or exceed the Threshold
Price for any particular trading day in the Investment Period or (ii) no trades
of Common Stock are made on the New York Stock Exchange on a day in the
Investment Period, then the Company shall exclude that trading day from the
Investment Period. The Agent shall return to a Participant one-twelfth of that
Participant's Optional Cash Purchase for each trading day of an Investment
Period that is excluded by the Company in accordance with the immediately
preceding sentence. The Company's election whether to establish a Threshold
Price for any particular Investment Period will not affect its rights to
establish a Threshold Price in any other Investment Period. Neither the Company
nor the Agent shall have any responsibility to notify any Participant regarding
the Company's establishment of a Threshold Price for an Investment Period. Any
Participant shall be able to confirm the existence of a Threshold Price by
telephoning the Company's Investor Relations at (877) 285-3111 during the three
business days preceding the applicable Investment Period.

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        D.    Discount Pricing.

            The Company may elect to establish, each month and in no event later
than three business days prior to the dividend record date, DSPP Investment Date
or the first day of the applicable Investment Period, as applicable, a discount
from the market price applicable to reinvested dividends and Optional Cash
Purchases with respect to the purchase of newly issued shares from the Company.
Any discount set by the Company with respect to an Optional Cash Purchase shall
apply to the entire Optional Cash Purchase, subject to the limitations set forth
below. The Company's election whether to establish a discount for dividend
reinvestment or Optional Cash Purchases for any dividend payment date, DSPP
Investment Date or Investment Period, as applicable, will not affect its rights
to establish a discount for any other dividend payment date, DSPP Investment
Date or Investment Period in the future. Any Participant may obtain the discount
applicable to the next dividend payment date, DSPP Investment Date or Investment
Period by telephoning the Investor Relations at (877) 285-3111 during the three
business days prior to the applicable dividend payment date, DSPP Investment
Date or Investment Period, as applicable. The discount, if any, shall be
determined by the Company in its sole discretion after reviewing the current
market conditions, the level of participation in the plan, and current and
projected capital needs. Such discount may vary but shall at no time be more
than 5% of the average of the high and low sales price per share of Common Stock
as reported by the New York Stock Exchange on the applicable dividend payment
date or DSPP Investment Date, and for each day during an Investment Period.
Notwithstanding the foregoing, the discount may not be varied by the Company
during an Investment Period, and shall apply uniformly to all Optional Cash
Purchases made under the WDP for each day of the respective Investment Period,
provided however, that such purchase price for each share purchased on any
particular trading day during the applicable Investment Period, after giving
effect to the applicable discount, less the per share amount of any brokerage
commissions, trading fees and other costs of purchase paid by the Company on
behalf of the Participants on such day, shall not be less than the Minimum
Purchase Price as defined in Section 5 below.

      E.    Procedures Applicable to Optional Cash Purchases.

            Participants shall not be obligated to make any DSPP investments or
WDP investments, and the amount of such investments may vary, in the case of a
purchase under the DSPP, among DSPP Investment Dates, and in the case of a
purchase under the WDP, among Investment Periods. With respect to a purchase
under the DSPP, if the "Optional Cash Only" box on the Enrollment Form is
checked, the Company will continue to pay cash dividends on the shares
registered in the Participant's name in the usual manner, but any DSPP Payment
received will be applied toward the purchase of additional shares of Common
Stock under the DSPP in accordance with the terms hereof. DSPP Payments shall be
delivered to the Agent at the address set forth in Section 22.

            In the event that any Participant's check with respect to a DSPP
Payment is

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returned unpaid for any reason, the Agent will consider the request for
investment of such money null and void and shall immediately remove from the
Participant's account shares, if any, purchased upon the prior credit of such
money. The Agent shall thereupon be entitled to sell these shares to satisfy any
uncollected amounts. If the net proceeds of the sale of such shares are
insufficient to satisfy the balance of such uncollected amounts, the Agent, in
addition to any other legal remedies it may have, shall be entitled to sell such
additional shares from the Participant's account to satisfy the uncollected
balance.

            A Participant may obtain a refund of any DSPP Payment or WDP Payment
not yet invested upon written request to the Agent at the address set forth in
Section 22, provided such request is received not later than two business days
prior to, in the case of a DSPP Payment, the next DSPP Investment Date, and in
the case of a WDP Payment, the commencement of the next Investment Period. If
the Agent receives the Participant's request for refund later than these
specified times, the DSPP Payment or WDP Payment, as applicable, will be applied
to the purchase of shares of Common Stock.

5.    SHARE PURCHASES

             As Agent for the Participants in the Plan, the Agent will receive
cash dividends from the Company with respect to Common Shares held by the
Participants and Optional Cash Purchases from the Participants. Shares to be
purchased under the DRIP, the DSPP and the WDP with such cash dividends or
Optional Cash Purchases may be purchased in the open market by the Agent on the
New York Stock Exchange or any securities exchange where shares of the Company's
Common Stock are traded, in the over-the-counter market, or in negotiated
transactions, and may be subject to such terms with respect to price, delivery
and other matters as to which the Agent may agree. Alternatively, or in
combination with open market purchases, the Company has the right to satisfy its
obligations under the DRIP, the DSPP and the WDP, by registering and issuing
additional shares of Common Stock, subject to compliance with the Securities Act
of 1933, as amended, and the rules and regulations thereunder. We may, without
giving you prior notice, change our determination as to whether the Agent will
purchase shares of Common Stock directly from us or in the open market or in
privately negotiated transactions from third parties (although we may not effect
such a change more than once in any three-month period) in connection with the
purchase of shares with reinvested dividends or from Optional Cash Purchases
under the DSPP or the WDP.

             In the event that the Company satisfies its obligations hereunder
by registering and issuing additional shares of Common Stock, the date of
issuance of shares to be purchased with reinvested dividends will be the
Dividend Payment Date, and the date of issuance of shares to be purchased with
Optional Cash Purchases will be the DSPP Investment Date or on each day on which
shares are purchased during the applicable WDP Investment Period, as the case
may be.

            When the Company is issuing shares of Common Stock to satisfy its
obligations under the DRIP or the DSPP, the purchase price will be the average
of the highest and

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lowest price per share as reported by the New York Stock Exchange or, if the
Common Stock is not then listed on the New York Stock Exchange, any other
securities exchange or national quotation service on which the Common Stock is
then traded or listed for quotation on such Dividend Payment Date or DSPP
Investment Date. When the Company is issuing shares of Common Stock to satisfy
its obligations under the WDP, the purchase price will be the average of the
highest and lowest price per share as reported by the New York Stock Exchange
or, if the Common Stock is not then listed on the New York Stock Exchange, any
other securities exchange or national quotation service on which the Common
Stock is then traded or listed for quotation on each day shares are purchased
during the applicable Investment Period. Shares of Common Stock purchased under
the DRIP, the DSPP and the WDP on the open market or in privately negotiated
transactions shall occur on the applicable Dividend Payment Date or DSPP
Investment Date or during the WDP Investment Period, as the case may be;
provided, however, that the Company may in the future advise the Agent that the
Agent may effect such purchases from time to time in its discretion over such
longer period not to exceed the 15 trading days following the applicable
Dividend Payment Date, DSPP Investment Date or WDP Investment Period; provided,
further, that in the case of such a purchase to be effected following a DSPP
Investment Date or WDP Investment Period, in no event shall any such purchase
occur on a Dividend Payment Date. If the Company exercises its discretion to
execute market purchases over an extended period, the date of issuance will be
the actual date of purchase of the Common Stock. In making purchases for a
Participant's account, the Agent may commingle a Participant's funds with those
of other Participants. The price at which shares will be deemed to have been
acquired for a Participant's account shall be the average price (on a day-by-day
basis) of all shares purchased by the Agent for the Plan with reinvested
dividends and/or DSPP Payments and/or WDP Payments then being invested. No
Participant shall have any authority or power to direct the time or price at
which Common Stock may be purchased. No interest will be paid on funds held for
investment.

            Notwithstanding anything to the contrary in this Plan, the amount
per share paid by a Participant for any shares of Common Stock (whether from
reinvested dividends or Optional Cash Purchases, and whether acquired from the
Company or through open market or privately negotiated transactions) purchased
on any particular trading day, less the amount per share of any brokerage
commissions, trading fees and any other costs of purchase paid by the Company,
if any, shall not be less than 95% of the average of the high and low sales
price of the Common Stock reported by the New York Stock Exchange on that
particular trading day (the "Minimum Purchase Price") In the event that shares
would be purchased below the Minimum Purchase Price, the Company will instead
reduce the discount, if any, or charge the Participant for such commissions,
fees or costs on such share purchase so that the Participant's purchase price
per share will equal the Minimum Purchase Price.

            The number of shares to be purchased for a Participant will depend
on the net amount of the Participant's dividends available for reinvestment
under the DRIP, and/or the aggregate amount of the DSPP Payment and/or WDP
Payment and the price per share

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of the Common Stock. Each Participant's account will be credited with the number
of shares, including fractions calculated to four decimal places, equal to the
total of a Participant's funds available for investment, divided by the
applicable per share purchase price of the shares purchased.

            The Agent shall have no responsibility as to the value of the Common
Stock acquired for a Participant's account. It is understood that for a number
of reasons, including observance of the Rules and Regulations of the Securities
and Exchange Commission requiring temporary curtailment or suspension of
purchases and the limitations on ownership contained in the Company's charter,
the whole amount of funds available in a Participant's account for the purchase
of Common Stock might not be applied to such purchase. The Agent shall not be
liable when conditions prevent the purchase of Common Stock or interfere with
the timing of such purchases.

6.    COSTS

            The Company will pay all of the costs of administrating the Plan
(other than brokerage commissions and trading fees). The Company will pass on to
each Participant the fees and commissions associated with the purchase and sale
of shares of Common Stock attributable to each Participant under the Plan.

7.    CUSTODIAL SERVICE

            All shares of Common Stock that are purchased by Participants under
the DRIP, DSPP or the WDP shall be held in the Participant's name and the shares
shall be added to the Participants' balance in the Plan. The Agent shall act as
custodian for all of the Participants' shares held in the Plan.

            A Participant may send to the Agent for safekeeping all Common Stock
certificates which the Participant holds. The Agent will keep all shares
represented by such certificates for safekeeping in book entry form, combined
with any full and fractional shares then held in the Plan in the name of the
Participant. In order to deposit share certificates in the Plan, a Participant
must submit a letter of instruction to the Agent. Shares certificates may be
withdrawn from the Plan by instructing the Agent in writing.

8.    STATEMENT OF ACCOUNT

            As soon as practicable after the purchase of Common Stock is
completed, the Agent will send each Participant a statement of account
confirming the transaction and itemizing any previous investment activity for
the calendar year. If a Participant participates in the Plan through a broker,
bank or nominee, the Participant's statement of account will be sent to the
respective broker, bank or nominee and the Participant must contact the broker,
bank or nominee to obtain the statement.

9.    DIVIDENDS ON PLAN SHARES

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            As the custodian for the Common Stock held in Participants' accounts
under the Plan (whether such shares were purchased under the DRIP, the DSPP or
the WDP) the Agent will receive dividends (less any applicable tax withholding
requirements imposed on the Company) for all Plan shares held on the applicable
record date, will credit such dividends to Participants' accounts on the basis
of shares held in these accounts, and will automatically reinvest such dividends
in additional Common Stock unless it is otherwise instructed in writing by the
Participant.

            If the Company distributes stockholders' subscription rights to
purchase additional shares of common stock or other securities, the Agent shall
sell the rights accruing to all shares held in a Participant's name when the
rights become separately tradable. The Agent will apply the net proceeds from
the sale of the rights to the purchase of Common Stock with the next monthly
Optional Cash Purchase. If a Participant does not want the subscription or such
other rights sold, such Participant may notify the Agent by submitting an
updated Enrollment Form which shall direct the Agent to distribute the rights
directly to the Participant.

10.   SALE OF PLAN SHARES

            A Participant can instruct the Agent in writing to sell any or all
of the whole shares of Common Stock held in the Plan. The written notification
to the Agent must include the number of shares to be sold. Any such request that
does not clearly indicate the number of shares to be sold will be returned to
the Participant with no action taken. The Agent will make the sale as soon as
practicable after receipt of a Participant's proper request and a check for the
proceeds, less brokerage commission, transfer taxes (if any) and a $15.00
service fee, will be sent by the Agent promptly after the settlement date. No
Participant shall have the authority or power to direct the date or sales price
at which Common Stock may be sold. A withdrawal/termination form will be
provided on the reverse side of the statement of account for this purpose.
Participants should mail this form to the Agent at the address set forth in
Section 22.

            A Participant may transfer ownership of all or any part of their
shares held in the Plan through gift, private sale or otherwise, by mailing to
the Agent at the above address a properly executed stock assignment, along with
a letter requesting the transfer and a Substitute Form W-9 completed by the
transferee. If any stock certificates in such Participant's account contain a
restrictive legend, the Agent will comply with the provisions of such
restrictive legend before effecting a sale or transfer of such restricted
shares. All transfers shall be subject to the limitations on ownership and
transfer provided herein and in the Company's charter.

11.   ISSUANCE OF SHARE CERTIFICATES

            Share certificates will not be issued unless a request is made to
the Agent. The number of shares held in the Plan by a Participant will be shown
on the regular statement

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of account provided to such Participant. By contacting the Agent by telephone or
in writing, a Participant may request, without charge, a share certificate for
any or all of the whole shares held for such Participant in the Plan. Each
certificate issued will be registered in the name or names in which the account
is maintained, unless otherwise instructed in writing. If a certificate is to be
issued in a name other than the name on the Plan Account, the Participant or
Participants must have their signature(s) guaranteed by a commercial banker or
broker. Certificates for fractional shares will not be issued under any
circumstances.

12.   TERMINATION OF PLAN PARTICIPATION

            In order to terminate participation in the Plan, a Participant must
notify the Agent in writing. The Company may also terminate the Plan by sending
written notice to the Participants and to the Agent. After the Agent receives
the termination notice, dividends will be sent to the stockholder in the usual
manner, and no further voluntary cash purchases may be made. A termination
notice will be effective upon receipt by the Agent, provided such notice is
received at least two business days prior to the next dividend record date,
Optional Cash Purchase Payment Date or commencement of the next Investment
Period. If a termination notice is not received by the Agent at least two
business days prior to any dividend record date, in the case of the DRIP, and in
the case of the DSPP and WDP, at least two business days prior to the
commencement of the DSPP Investment Date or Investment Period respectively, it
will not be processed until after purchases made from dividends paid have been
completed and credited to Participants' accounts. Once termination has been
effected, the Agent will issue to the Participant a certificate for all whole
shares held by a Participant under the Plan. Alternatively, a Participant may
specify in the termination notice that some or all of the shares be sold. The
Agent will deliver a check to the Participant for the net proceeds.

            If a Participant transfers shares represented by certificates
registered in such Participant's name on the Company's books but does not notify
the Agent, the Agent will continue to reinvest dividends on shares held in such
Participant's account under the Plan until otherwise directed.

            If a Participant's Plan account balance falls below one full share,
the Agent reserves the right to sell the fractional share and remit the
proceeds, less any applicable fees, to the Participant at the Participant's
address appearing in the Agent's records.

13.   PLAN ADMINISTRATION

            The Agent, or a successor selected by the Company, will administer
the Plan for Participants, keep records, send statements of account to
Participants, answer Participants' questions and perform other duties set forth
herein or otherwise related to the Plan. All inquiries regarding the Plan should
be sent to the Agent at the address set forth in Section 22.

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            As soon as practicable after each purchase for a Participant's
account, a statement of account will be mailed to the Participant by the Agent.
In addition, the Agent shall send to each Participant all communications sent to
other stockholders, including, if applicable, any annual and quarterly reports
to stockholders, proxy statements and dividend income information for tax
reporting purposes.

            The Company may remove the Agent upon 60 days prior written notice
to the Agent (the "Termination Notice"). The Agent may resign as Agent upon 60
days prior written notice to the Company. Upon any such removal or resignation,
the Agent shall be relieved and discharged of any further responsibilities with
respect to its duties thereunder. Not later than 30 days after the date on which
the Agent receives or delivers, as the case may be, the Termination Notice (the
"Termination Notice Date"), the Company shall deliver to the Agent a written
notice instructing the Agent to deliver to the Company or its designee all of
the statements of account, the shares of Common Stock held by the Agent under
the Plan, and all other books and records in connection with the administration
of the Plan (collectively, the "Plan Records"). The Agent shall comply with
instruction and deliver the Plan Records to the Company or its designee not
later than 10 business days following the date it receives such instruction;
provided, however, that if no instruction is received by the Agent by the 30th
day following the Termination Notice Date, the Agent shall deliver the Plan
Records to the Company not later than 45 days after the Termination Notice Date.
The Agent shall cooperate with and assist the Company or any successor agent
with the transfer of the Plan Records.

            As Agent, BankBoston N.A. shall act in accordance with the Plan and
in accordance with applicable laws, including without limitation the Securities
Exchange Act of 1934, as amended (the "Exchange Act") and interpretations
thereof by the Securities and Exchange Commission.

            The Agent shall keep appropriate records concerning the Plan
accounts, purchases and sales of the Company's securities made under the Plan
and Participants' addresses of record and shall send statements of account and
confirmations to each Participant in accordance with the provisions hereof.
Without limiting the foregoing, the Agent shall maintain and retain for a period
of not less than two years from the date of the event the following information:
(i) the dates and substance of any materials distributed in connection with the
Plan, (ii) the number of Participants as of the end of each month; (iii) the
volume of Company securities purchased under the Plan by the Agent each month;
and (iv) a record of any period during which the Company is engaged in any other
distribution of shares of its Common Stock or other Company securities for
purposes of Regulation M under the Exchange Act. The Company shall notify the
Agent of the commencement and the termination of any such period on the date of
any such commencement or termination:

            The Agent:

            (a)   shall have no duties or obligations other than those
                  specifically set forth herein or as may subsequently be agreed

<PAGE>   12

                to in writing between the Agent and the Company. Without
                limiting the foregoing, nothing herein shall impose any
                fiduciary duty upon the Agent to any Participant, as such term
                is defined herein;

            (b) shall be regarded as making no representation and having no
                responsibilities as to the validity, sufficiency, value, or
                genuineness of any of the Company's securities purchased or sold
                in connection herewith, and will not be required to or be
                responsible for and will make no representations as to, the
                validity, sufficiency, value or genuineness of any of the
                Company's securities;

            (c) shall not be obligated to take any legal action hereunder; if,
                however, the Agent determines to take any legal action
                hereunder, and where the taking of such action might, in its
                reasonable judgment, subject or expose it to any expense or
                liability, the Agent shall not be required to act unless it
                shall have been furnished with an indemnity reasonably
                satisfactory to it;

            (d) may rely on and shall be fully authorized and protected in
                acting or failing to act in good faith reliance upon any
                certificate, instrument, opinion, notice, letter, telegram,
                telex, facsimile transmission or other document or security
                delivered to and believed by the Agent to be genuine and to have
                been signed by the proper person or persons;

            (e) shall not be liable or responsible for any failure on the part
                of the Company or any Participant to comply with any of their
                respective obligations relating to the Plan or under applicable
                law, including without limitation obligations under applicable
                securities laws;

            (f) shall have no obligation to make any payment unless it has
                received the necessary funds as set forth herein to make such
                payments in full;

            (g) may consult with counsel reasonably satisfactory to the Agent,
                including in-house counsel, if any, or counsel to the Company,
                and the advice of such counsel shall be full and complete
                authorization and protection in respect of any action taken,
                suffered, or omitted by the Agent in good faith and in
                accordance with the advice of such counsel;

<PAGE>   13

            (h) may perform any of its duties hereunder either directly or by or
                through agents or attorney which are not affiliates of the
                Company (except for purchase and sale orders submitted by
                Participants, including accompanying funds, all of which will be
                handled only by the Agent's personnel), provided that (i) any
                activities that constitute transfer agent functions, as defined
                in section 3(a)(25) of the Exchange Act, must be conducted
                either by the Agent itself or by a service organization that is
                a registered transfer agent under the Exchange Act, and (ii) no
                such agent or attorney shall receive compensation based on the
                number and type of orders or transactions processed through the
                Plan. The Agent shall not be liable or responsible for any
                misconduct or negligence on the part of any agent or attorney
                appointed with reasonable care by it hereunder; and

            (i) is not authorized, and shall have no obligation, to pay any
                brokers, dealers, or soliciting fees to any person.

            In exercising all of its duties and obligations hereunder, the Agent
shall use the same degree of skill in its exercise as a prudent man would
exercise or use under the circumstances in the conduct of his own affairs.

            Notwithstanding the foregoing, the Agent may not be relieved from
liability for its own negligent action, its own negligent failure to act, or its
own willful misconduct, except that the Agent shall not be liable for any error
or judgment made in good faith unless it is proved that the Agent was negligent
in ascertaining the pertinent facts.

            The Agent may charge reasonable fees for its services in connection
with the Plan (to the extent consistent with the provisions of the Plan)
including without limitation fees for purchase and sale order processing,
enrollment, custody, account maintenance and dividend reinvestment and shall be
reimbursed for all its reasonable out-of-pocket costs and expenses. All such
fees, costs and expenses shall be paid by the Company, except that Participants
and other eligible book entry stockholders will be required to pay a nominal
commission and fee for each sale order and a nominal fee for the issuance of
duplicate statements of account or transaction notices. The Agent may from time
to time by notice to the Company and the Participants establish the amount of
any such fees.

            The Agent shall have the authority to undertake any act reasonably
necessary to fulfill its duties as set forth herein.

            In administering the Plan, neither the Agent, the Company nor any
agent for either will be liable for (i) any act done in good faith or for any
good faith omission to act, including, without limitation, any claim of
liability arising out of failure to terminate a Participant's account upon such
Participant's death or adjudicated incompetence prior to

<PAGE>   14

the receipt of written notice of such death or adjudicated incompetence, (ii)
the prices at which Common Stock are purchased for the Participant's account,
(iii) the times when purchases are made or (iv) fluctuations in the per share
market value of the Common Stock. The Agent shall not be liable for any failure
or delays arising out of conditions beyond its reasonable control including, but
not limited to, work stoppages, fires, civil disobedience, riots, rebellions,
storms, electrical, mechanical, computer or communications facilities failures,
acts of God or similar occurrences.

            Neither the Agent, the Company nor any agent for either shall have
any duties, responsibilities or liabilities except such as are expressly set
forth herein and in the Agent Agreement. The Company specifically disclaims any
responsibility for any of the Agent's actions or inactions in connection with
the administration hereof.

            The Company will indemnify and hold harmless the Agent and its
officers, directors, shareholders, and agents from and against any loss,
liability, damage or expense (including reasonable attorneys' fees and expenses)
(a "Loss") incurred as a result of the performance of the Agent's duties
hereunder, provided that such Loss is not (a) due to any negligent or bad faith
act or omission by the Agent, (b) due to a failure by the Agent to act in
accordance with the provisions hereof or the written instructions of the Company
or (c) due to a breach by the Agent of its agreements set forth herein.

14.   PLEDGE OF SHARES

            Shares held in the Plan may not be pledged or assigned, and any such
purported pledge or assignment shall be void.

15.   VOTING

            The Agent will not vote any shares that it holds for a Participant's
account except as directed by the Participant. If no instructions are received,
the shares will not be voted. Each Participant that is a registered holder will
receive a proxy voting card for the total of their whole shares, including
shares that they hold in the Plan. Neither the Company nor the Agent shall be
required to send proxy materials to any Participant that holds shares of Common
Stock through a broker, bank or nominee and any such Participant must contact
such broker, bank or nominee to vote their shares.

16.   SHARE DIVIDENDS, ETC.

            Any Common Stock dividend upon, or shares of Common Stock issued as
a result of, splits of Common Stock, both full and fractional, will be credited
by the Agent to Participants' accounts. Participation in any rights offering
will be based upon both the Common Stock registered in Participants' names and
the Common Stock credited to Participants' accounts. Rights applicable to Common
Stock credited to a Participant's account under the Plan will be sold by the
Agent and proceeds will be credited to the Participant's account under the Plan
and applied to the purchase of Common Stock on the

<PAGE>   15

next DSPP Investment Date (or over the 15 trading days following the next DSPP
Investment Date as provided in Section 5 of this Plan). Any Participant who
wishes to exercise, transfer or sell the rights applicable to the Common Stock
credited to the Participant's account under the Plan must request, prior to the
record date for the issuance of any such rights, that the Common Stock credited
to the Participant's account be transferred from the Participant's account and
registered in the Participant's name.

17.      OWNERSHIP LIMITATIONS

            The Company's charter places certain restrictions upon the actual
and constructive ownership of shares of each class or series of stock, applied
to each class or series of stock separately. With respect to the Common Stock of
the Company, any one person or entity is limited to owning, actually and
constructively, no more than 9.8% of the outstanding Common Stock of the Company
(the "Ownership Limit"). The percentage of ownership is measured by either value
or absolute number of shares, whichever measurement is more restrictive. To the
extent any transfer of Common Stock, reinvestment of dividends or Optional Cash
Purchase elected by a stockholder would cause such stockholder or any other
person or entity to exceed the Ownership Limit or otherwise violate the
Company's charter, such transfer or investment will be void ab initio as to that
stockholder or the other person or entity, and such stockholder or other person
or entity will be entitled to receive cash dividends (without interest) in lieu
of such reinvestment or to a return of such Optional Cash Purchase (without
interest), as applicable.

            In order to monitor the Ownership Limit and the limitation of cash
purchases which may be made under the Plan, the Company has right to aggregate
all plan accounts that it believes, in its sole discretion, are under common
control or management or to have common ultimate beneficial ownership. If the
Company exercises such right, it shall aggregate the accounts and return,
without interest, within 35 days of receipt, any amounts in excess of the
investment limitations applicable to a single account received in respect of all
such accounts.

18.   AMENDMENT OR TERMINATION OF PLAN

            The Plan may be amended, modified, suspended, supplemented or
terminated by the Company at any time, provided, however, that when necessary or
appropriate to comply with law or the rules or policies of the Securities and
Exchange Commission or other applicable regulatory authority, such action shall
be effective only by mailing appropriate written notice at least 30 days prior
to the effective date of such action to each Participant. Any such action shall
be deemed accepted by the Participant unless prior to the effective date
thereof, the Agent receives written notice of the termination of the
Participant's account. Any such amendment may include an appointment by the
Company of a successor agent under the terms and conditions set forth herein, in
which event the Company is authorized to pay such successor agent for the
account of each Participant all dividends and distributions payable on Common
Stock held by the Participant under the Plan for application by such successor
agent as provided herein. Notwithstanding the

<PAGE>   16

foregoing, such action shall not have any retroactive effect that would
prejudice the interests of the Participants. In the event of termination,
certificates for whole shares held by each Participant in the Plan will be
delivered to such Participant together with a check for the net proceeds of the
value of any fractional shares, which value will be equal to the average of the
highest and lowest price per share as then reported by the New York Stock
Exchange or, if the Common Stock is not then listed on the New York Stock
Exchange, any other securities exchange or national quotation service on which
the Common Stock is then traded or listed for quotation on the date of such
termination.

19.   GOVERNING LAW

            The terms and conditions of the Plan and its operation shall be
governed by the internal laws of the State of Maryland, without regard to
otherwise applicable principles of conflicts of law.

20.   INTERPRETATION

            Any question of interpretation arising under the Plan will be
determined by the Company, and any such determination will be final.

21.   EFFECTIVE DATE

            The effective date of the Plan shall be July 9,1999.

22.   CORRESPONDENCE AND QUESTIONS

            All correspondence and questions regarding the Plan and any account
thereunder should be directed to:

                                BankBoston N.A.
                       c/o EquiServe Limited Partnership
                               150 Royall Street
                          Canton, Massachusetts 02021
                            Telephone (800) 331-9474