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                                                                    EXHIBIT 99.4
                                [AMB LETTERHEAD]


Dear Investor:

We are pleased to offer you a convenient and economic method of purchasing
shares of AMB Property Corporation's common stock and investing all or a portion
of your cash dividends in additional shares of common stock through our Dividend
Reinvestment and Direct Purchase Plan (the "Plan"). The Plan is a comprehensive
package of shareholder services. A copy of the Plan Prospectus is enclosed for
your review along with the Enrollment Form.

Some of the highlights of the Plan are as follows:

-  You may purchase additional shares of common stock by automatically
   reinvesting all or a portion of your cash dividends in common stock through
   the Plan.

-  You may also purchase shares of stock by making optional cash purchases of
   $500 to $5,000 in any calendar month.

-  You may purchase shares of stock in excess of $5,000 in any calendar month
   with our prior written consent through our Waiver Discount Program.

-  We may offer a discount of up to 5% determined by us from time to time on
   newly issued shares of common stock.

-  You may deposit your common stock certificate for safekeeping with the Plan
   Administrator.

If after reading the enclosed prospectus you would like to enroll, please
complete the Enrollment Form as indicated and return it in the enclosed envelope
to the Plan Administrator, EquiServe.

If you have any questions regarding the Plan please contact EquiServe at
1-800-331-9474 or AMB's Investor Relations line at 877-285-3111 (toll free). We
hope that you find the features offered in this Plan interesting and thank you
for your support of AMB Property Corporation.

Sincerely,


/s/ CHRISTINE G. SCHADLICH



Christine G. Schadlich
Vice President, Investor Relations and Corporate Communication
