<PAGE>   1

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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                             ---------------------

                                   FORM 10-Q

(Mark One)
[X]              QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
                        OF THE SECURITIES EXCHANGE ACT OF 1934
                   FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2001 OR

[ ]              TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
                        OF THE SECURITIES EXCHANGE ACT OF 1934
        FOR THE TRANSITION PERIOD FROM                   TO

                        COMMISSION FILE NUMBER: 1-13625

                             ---------------------

                       EOP OPERATING LIMITED PARTNERSHIP
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                            <C>
                   DELAWARE                                      36-4156801
       (State or other jurisdiction of                        (I.R.S. Employer
        incorporation or organization)                      Identification No.)
          TWO NORTH RIVERSIDE PLAZA,                               60606
        SUITE 2100, CHICAGO, ILLINOIS                            (Zip Code)
   (Address of principal executive offices)
</TABLE>

                                 (312) 466-3300
              (Registrant's telephone number, including area code)

                             ---------------------

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes [X]  No [ ]
                     APPLICABLE ONLY TO CORPORATE ISSUERS:
On April 30, 2001, 309,749,050 of the registrant's Units were outstanding.

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<PAGE>   2

                                    PART I.
                             FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS

                       EOP OPERATING LIMITED PARTNERSHIP
                          CONSOLIDATED BALANCE SHEETS

<TABLE>
<CAPTION>
                                                                 MARCH 31,     DECEMBER 31,
(DOLLARS IN THOUSANDS, EXCEPT PER UNIT AMOUNTS)                    2001            2000
------------------------------------------------------------    -----------    ------------
                                                                (UNAUDITED)
<S>                                                             <C>            <C>
ASSETS:
  Investment in real estate.................................    $17,543,327    $17,460,534
  Developments in process...................................         81,079         70,422
  Land available for development............................         88,424         88,424
  Accumulated depreciation..................................     (1,100,273)      (978,055)
                                                                -----------    -----------
    Investment in real estate, net of accumulated
     depreciation...........................................     16,612,557     16,641,325
  Cash and cash equivalents.................................         37,610         53,256
  Tenant and other receivables (net of allowance for
    doubtful accounts of $2,563 and $1,873, respectively)...         84,648        101,784
  Deferred rent receivable..................................        222,187        207,088
  Escrow deposits and restricted cash.......................         45,131         39,832
  Investment in unconsolidated joint ventures...............      1,135,205      1,164,613
  Deferred financing costs (net of accumulated amortization
    of $25,273 and $21,756, respectively)...................         78,338         81,854
  Deferred leasing costs (net of accumulated amortization of
    $50,966 and $39,906, respectively)......................        158,779        151,178
  Prepaid expenses and other assets (net of discounts of
    $78,337 and $78,871, respectively)......................        348,843        353,323
                                                                -----------    -----------
         Total Assets.......................................    $18,723,298    $18,794,253
                                                                ===========    ===========
LIABILITIES AND PARTNERS' CAPITAL:
  Mortgage debt (including a net discount of $(19,056) and
    $(17,825), respectively)................................    $ 2,784,255    $ 2,915,801
  Unsecured notes (including a net discount of $(3,596) and
    $(3,807), respectively).................................      5,836,404      5,836,193
  Line of credit............................................         37,500         51,000
  Accounts payable and accrued expenses.....................        418,781        497,811
  Distribution payable......................................        160,679          3,681
  Other liabilities.........................................        181,915        204,298
                                                                -----------    -----------
         Total Liabilities..................................      9,419,534      9,508,784
                                                                -----------    -----------
  Commitments and contingencies
  Minority Interests -- partially owned properties..........        198,280        197,161
                                                                -----------    -----------
  Preferred Units, 100,000,000 authorized:
    8.98% Series A Cumulative Redeemable Preferred Units,
     liquidation preference $25.00 per unit, 7,994,000
     issued and outstanding.................................        199,850        199,850
    5.25% Series B Convertible, Cumulative Redeemable
     Preferred Units, liquidation preference $50.00 per
     unit, 5,990,000 and 6,000,000 issued and outstanding,
     respectively...........................................        299,500        300,000
    8.625% Series C Cumulative Redeemable Preferred Units,
     liquidation preference $25.00 per unit, 4,562,900
     issued and outstanding.................................        114,073        114,073
  General Partners Capital..................................         70,495         70,490
  Limited Partners Capital..................................      8,457,310      8,447,021
  Deferred compensation.....................................        (30,157)       (14,871)
  Accumulated other comprehensive loss......................         (5,587)       (28,255)
                                                                -----------    -----------
         Total Partners' Capital............................      9,105,484      9,088,308
                                                                -----------    -----------
         Total Liabilities and Partners' Capital............    $18,723,298    $18,794,253
                                                                ===========    ===========
</TABLE>

                            See accompanying notes.

                                        2
<PAGE>   3

                       EOP OPERATING LIMITED PARTNERSHIP

                     CONSOLIDATED STATEMENTS OF OPERATIONS
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                            FOR THE THREE MONTHS ENDED
                                                                     MARCH 31,
                                                            ---------------------------
(DOLLARS IN THOUSANDS, EXCEPT PER UNIT AMOUNTS)                 2001           2000
----------------------------------------------------------  ------------   ------------
<S>                                                         <C>            <C>
REVENUES:
  Rental..................................................  $   509,135    $   358,366
  Tenant reimbursements...................................       97,321         62,983
  Parking.................................................       30,590         26,731
  Other...................................................       13,163         12,856
  Fee income..............................................        2,172          2,235
  Interest/dividends......................................       10,835          5,704
                                                            -----------    -----------
           Total revenues.................................      663,216        468,875
                                                            -----------    -----------
EXPENSES:
  Interest:
     Expense incurred.....................................      157,940        100,532
     Amortization of deferred financings costs............        1,326          1,377
  Depreciation............................................      114,566         83,889
  Amortization............................................        9,082          4,386
  Real estate taxes.......................................       76,662         57,910
  Insurance...............................................        3,307          2,740
  Repairs and maintenance.................................       65,600         47,899
  Property operating......................................       69,022         46,788
  Ground rent.............................................        3,081          2,024
  General and administrative..............................       25,639         19,651
                                                            -----------    -----------
           Total expenses.................................      526,225        367,196
                                                            -----------    -----------
Income before allocation to minority interests, income
  from investment in unconsolidated joint ventures, net
  gain on sales of real estate, extraordinary items and
  cumulative effect of a change in accounting principle...      136,991        101,679
Minority Interests -- partially owned properties..........       (3,253)          (553)
Income from investment in unconsolidated joint ventures...       15,426         11,374
Net gain on sales of real estate..........................           --          3,862
                                                            -----------    -----------
Income before extraordinary items and cumulative effect of
  a change in accounting principle........................      149,164        116,362
Extraordinary items.......................................           --           (611)
Cumulative effect of a change in accounting principle.....       (1,142)            --
                                                            -----------    -----------
Net income................................................      148,022        115,751
Put option settlement.....................................           --         (1,030)
Preferred distributions, net..............................      (10,884)       (10,697)
                                                            -----------    -----------
Net income available for Units............................  $   137,138    $   104,024
                                                            ===========    ===========
Net income available per weighted average Unit
  outstanding -- Basic....................................  $       .39    $      0.37
                                                            ===========    ===========
Weighted average Units outstanding -- Basic...............  348,476,502    281,380,638
                                                            ===========    ===========
Net income available per weighted average Unit and unit
  equivalent outstanding -- Diluted.......................  $       .39    $      0.37
                                                            ===========    ===========
Weighted average Units and unit equivalents
  outstanding -- Diluted..................................  351,400,853    283,568,648
                                                            ===========    ===========
</TABLE>

                            See accompanying notes.

                                        3
<PAGE>   4

                       EOP OPERATING LIMITED PARTNERSHIP

              CONSOLIDATED STATEMENTS OF NET COMPREHENSIVE INCOME
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                              FOR THE THREE MONTHS
                                                                 ENDED MARCH 31,
                                                              ---------------------
(DOLLARS IN THOUSANDS)                                          2001        2000
------------------------------------------------------------  ---------   ---------
<S>                                                           <C>         <C>
Net income..................................................  $148,022    $115,751
Other comprehensive income (loss):
  Unrealized holding (losses)/gains arising during the
     period.................................................    (1,416)     27,540
  Recognition of permanent impairment on marketable
     securities.............................................    24,084          --
                                                              --------    --------
Net comprehensive income....................................  $170,690    $143,291
                                                              ========    ========
</TABLE>

                            See accompanying notes.
                                        4
<PAGE>   5

                       EOP OPERATING LIMITED PARTNERSHIP

                     CONSOLIDATED STATEMENTS OF CASH FLOWS
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                                FOR THE THREE MONTHS ENDED
                                                                        MARCH 31,
                                                                --------------------------
                   (DOLLARS IN THOUSANDS)                          2001           2000
------------------------------------------------------------    -----------    -----------
<S>                                                             <C>            <C>
OPERATING ACTIVITIES:
  Net income................................................    $  148,022     $  115,751
  Adjustments to reconcile net income to net cash provided
    by operating activities:
    Depreciation and amortization...........................       124,974         89,652
    Amortization of discounts included in interest/dividend
     income.................................................          (534)            --
    Amortization of premiums/discounts on unsecured notes
     and terminated interest rate protection agreements.....         1,171            936
    Amortization of deferred revenue included in other
     income.................................................          (533)        (1,036)
    Compensation related to restricted shares issued to
     employees by Equity Office.............................         2,159          1,555
    Income from unconsolidated joint ventures...............       (15,426)       (11,374)
    Net gain on sales of real estate........................            --         (3,862)
    Extraordinary items.....................................            --            611
    Cumulative effect of a change in accounting principle...         1,142             --
    Provision for doubtful accounts.........................           755             58
    Allocation to minority interests........................         3,253            553
    Changes in assets and liabilities:
      Decrease in rents receivable..........................        16,381         11,837
      (Increase) in deferred rent receivables...............       (15,099)       (12,323)
      Decrease (increase) in prepaid expenses and other
       assets...............................................         4,698         (6,798)
      (Decrease) in accounts payable and accrued expenses...       (79,703)       (71,014)
      Increase (decrease) in other liabilities..............         1,541         (5,057)
                                                                ----------     ----------
         Net cash provided by operating activities..........       192,801        109,489
                                                                ----------     ----------
INVESTING ACTIVITIES:
  Property dispositions.....................................         8,600             --
  Payments of disposition costs for sales of real estate....            --           (358)
  Payments for capital and tenant improvements..............       (53,910)       (50,025)
  Distributions from unconsolidated joint ventures..........        24,724          6,804
  Investments in unconsolidated joint ventures..............       (21,248)        (5,026)
  Payments of lease acquisition costs.......................       (16,539)       (14,440)
  (Increase) in escrow deposits and restricted cash.........        (5,299)        (2,884)
                                                                ----------     ----------
    Net cash (used for) investing activities................       (63,672)       (65,929)
                                                                ----------     ----------
FINANCING ACTIVITIES:
  Repurchase of Units.......................................            --       (119,633)
  Proceeds from exercise of share options...................        12,572          1,510
  Redemption of Units for cash..............................            --         (3,780)
  Distributions to unitholders..............................          (487)        (2,154)
  Payment of preferred distributions........................       (10,884)       (10,884)
  Repurchase of preferred units, including transaction
    costs...................................................            --           (890)
  Distributions to minority interests in partially owned
    properties..............................................        (2,161)            --
  Proceeds from unsecured notes.............................            --        499,320
  Proceeds from lines of credit.............................     1,646,700      1,075,100
  Principal payments on mortgage debt.......................      (130,315)      (168,134)
  Principal payments on lines of credit.....................    (1,660,200)    (1,296,100)
  Payments of loan costs....................................            --         (3,877)
                                                                ----------     ----------
    Net cash (used for) financing activities................      (144,775)       (29,522)
                                                                ----------     ----------
  Net (decrease) increase in cash and cash equivalents......       (15,646)        14,038
  Cash and cash equivalents at the beginning of the
    period..................................................        53,256          2,338
                                                                ----------     ----------
  Cash and cash equivalents at the end of the period........    $   37,610     $   16,376
                                                                ==========     ==========
SUPPLEMENTAL INFORMATION:
  Interest paid during the period, including capitalized
    interest of $5,027 and $5,143, respectively.............    $  183,540     $  132,470
                                                                ==========     ==========
NON-CASH INVESTING AND FINANCING ACTIVITIES:
  Escrow deposits provided by property dispositions.........            --     $  (45,620)
                                                                ==========     ==========
</TABLE>

                            See accompanying notes.
                                        5
<PAGE>   6

                       EOP OPERATING LIMITED PARTNERSHIP

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                  (UNAUDITED)

     The consolidated financial statements of EOP Partnership have been prepared
pursuant to the Securities and Exchange Commission ("SEC") rules and
regulations. The following notes highlight significant changes to the notes to
the December 31, 2000 audited consolidated financial statements of EOP
Partnership and should be read in conjunction with the financial statements and
notes thereto included in the Form 10-K and present interim disclosures as
required by the SEC.

NOTE 1 -- BUSINESS AND FORMATION OF EOP PARTNERSHIP

     As used herein, "EOP Partnership" means EOP Operating Limited Partnership,
a Delaware limited partnership, together with its subsidiaries. EOP Partnership
is a subsidiary of Equity Office Properties Trust ("Equity Office"), a Maryland
real estate investment trust, which was formed on October 9, 1996 to continue
and expand the national office property business organized by Mr. Samuel Zell,
Chairman of the Board of Trustees of Equity Office, and to complete the
consolidation of the Equity Office Predecessors (the "Consolidation"). Equity
Office completed its initial public offering (the "IPO") on July 11, 1997 having
sold its common shares of beneficial interest, $0.01 par value per share
("Common Shares"). The net proceeds of the IPO were contributed to EOP
Partnership in exchange for units of partnership interest ("Units"). EOP
Partnership is a fully integrated, self-administered and self-managed real
estate company engaged in acquiring, owning, managing, developing, leasing and
renovating office properties and parking facilities. Equity Office's assets,
which include investments in joint ventures, are owned by, and substantially all
of its operations are conducted through EOP Partnership. Equity Office is the
general partner of EOP Partnership. Equity Office has elected to be taxed as a
real estate investment trust ("REIT") for federal income tax purposes and
generally will not be subject to federal income tax if it distributes 100% of
its taxable income and complies with a number of organizational and operational
requirements. As of March 31, 2001, EOP Partnership owned or had an interest in
380 office properties (the "Office Properties") containing approximately 99.0
million rentable square feet of office space and owned nine stand-alone parking
facilities (the "Parking Facilities" and, together with the Office Properties,
the "Properties") containing approximately 14,244 parking spaces. The weighted
average occupancy for the Office Properties at March 31, 2001, was approximately
94.2%. The Office Properties are located in 103 submarkets in 37 markets in 24
states and the District of Columbia. The Office Properties, by rentable square
feet, are located approximately 51.3% in central business districts ("CBDs") and
48.7% in suburban markets.

NOTE 2 -- SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

  Basis of Presentation

     The consolidated financial statements represent the financial condition and
results of EOP Partnership and its subsidiaries. All intercompany transactions
and balances have been eliminated in consolidation.

  Use of Estimates

     The preparation of the consolidated financial statements in conformity with
accounting principles generally accepted in the United States requires
management to make estimates and assumptions that affect the reported amounts of
assets and liabilities and disclosure of contingent assets and liabilities at
the date of the financial statements and the reported amounts of revenues and
expenses during the reporting periods. Actual results could differ from those
estimates.

  Unaudited Interim Statements

     The consolidated financial statements as of and for the three months ended
March 31, 2001 and 2000 and related footnote disclosures are unaudited. In the
opinion of management, such financial statements reflect all

                                        6
<PAGE>   7

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

adjustments necessary for a fair presentation of the results of the interim
periods. All such adjustments are of a normal, recurring nature.

  Reclassifications

     Certain reclassifications have been made to the previously reported 2000
statements in order to provide comparability with the 2001 statements reported
herein. These reclassifications have not changed the 2000 results or partners'
capital.

NOTE 3 -- DISPOSITIONS

     On January 25, 2001, Warner Park Center in Woodland Hills, CA was disposed
of for approximately $8.95 million to Adler Realty Advisors, Inc. and its
investors. There was no gain or loss on the sale of Warner Park Center. The
building consisted of 57,366 square feet and was 66.3% occupied.

NOTE 4 -- INVESTMENT IN UNCONSOLIDATED JOINT VENTURES

     EOP Partnership has several investments in unconsolidated joint ventures
consisting of Office Properties, Parking Facilities, a management company and a
company that provides fully furnished office space to tenants. Combined
summarized financial information of the unconsolidated joint ventures is as
follows:

<TABLE>
<CAPTION>
                                                                DECEMBER 31,    MARCH 31,
                   (DOLLARS IN THOUSANDS)                           2000           2001
------------------------------------------------------------    ------------    ----------
<S>                                                             <C>             <C>
Balance Sheets:
  Real estate, net..........................................     $2,912,972     $2,928,225
  Other assets..............................................        226,183        239,267
                                                                 ----------     ----------
          Total Assets......................................     $3,139,155     $3,167,492
                                                                 ==========     ==========
  Mortgage debt.............................................     $1,335,100     $1,333,304
  Other liabilities.........................................        131,850        138,210
  Partners' and shareholders' equity........................      1,672,205      1,695,978
                                                                 ----------     ----------
          Total Liabilities and Partners' and Shareholders'
            Equity..........................................     $3,139,155     $3,167,492
                                                                 ==========     ==========
EOP Partnership's share of equity...........................     $1,002,226     $1,016,213
Net excess of cost of investments over/under the net book
  value of underlying net assets, net of accumulated
  depreciation of $18,061 and $16,905, respectively.........        132,979        148,400
                                                                 ----------     ----------
Carrying value of investments in unconsolidated joint
  ventures..................................................     $1,135,205     $1,164,613
                                                                 ==========     ==========
EOP Partnership's share of unconsolidated mortgage debt.....     $  835,873     $  834,093
                                                                 ==========     ==========
</TABLE>

                                        7
<PAGE>   8

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                              FOR THE THREE MONTHS
                                                                ENDED MARCH 31,
                                                              --------------------
(DOLLARS IN THOUSANDS)                                          2001        2000
------------------------------------------------------------  ---------   --------
<S>                                                           <C>         <C>
Statements of Operations:
  Revenues..................................................  $130,819    $71,270
                                                              --------    -------
  Expenses:
     Interest expense.......................................    25,310     10,741
     Depreciation and amortization..........................    20,980     12,072
     Operating expenses.....................................    55,643     27,978
                                                              --------    -------
          Total expenses....................................   101,933     50,791
                                                              --------    -------
  Net income before cumulative effect of a change in
     accounting principle...................................    28,886     20,479
  Cumulative effect of a change in accounting principle.....    (2,279)        --
                                                              --------    -------
  Net income................................................  $ 26,607    $20,479
                                                              ========    =======
EOP Partnership's share of net income.......................  $ 15,426    $11,374
                                                              ========    =======
EOP Partnership's share of interest expense.................  $ 16,415    $ 5,114
                                                              ========    =======
EOP Partnership's share of depreciation and amortization
  (real estate related).....................................  $ 12,677    $ 7,259
                                                              ========    =======
</TABLE>

NOTE 5 -- MORTGAGE DEBT

     The following mortgage notes were repaid or prepaid with available cash
and/or borrowings from the line of credit during the current quarter:

<TABLE>
<CAPTION>
                                                 PAYOFF AMOUNT
DATE PAID                PROPERTY                (IN THOUSANDS)
---------       --------------------------       --------------
<S>             <C>                              <C>
1/19/2001       Palo Alto Square                    $ 49,950
2/15/2001       Community Corporate Center            16,553
2/23/2001       Wachovia Center                       25,314
2/28/2001       Centerpointe I & II                   29,012
                                                    --------
                                                    $120,829
                Total
                                                    ========
</TABLE>

NOTE 6 -- PARTNERS' CAPITAL

  Units

     The following table presents the changes in the issued and outstanding
Units since January 1, 2001:

<TABLE>
<S>                                                             <C>
OUTSTANDING AT JANUARY 1, 2001..............................    349,027,487
Retired Units...............................................       (113,829)
Issued for property acquisitions............................          7,930
Issued to Equity Office related to Common Shares issued for
  share option exercises....................................        537,063
Restricted Units issued/cancelled, net......................        598,066
Units issued in exchange for the conversion of 10,000 Series
  B Preferred Units.........................................         14,005
Units issued to Equity Office for Common Shares issued
  through the Dividend Reinvestment Program.................          1,743
                                                                -----------
OUTSTANDING AT MARCH 31, 2001...............................    350,072,465
                                                                ===========
</TABLE>

                                        8
<PAGE>   9

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

  Preferred Units

     On March 29, 2001, a holder of 10,000 Series B Preferred Units exercised
its right to convert its Series B Preferred Units into 14,005 Units.

  Distributions

     The following tables summarize the distributions paid or declared to
unitholders and preferred unitholders during the current quarter:

<TABLE>
<CAPTION>
                                                             DISTRIBUTION
                                                                AMOUNT
                                                               PER UNIT      DATE PAID    RECORD DATE
                                                             ------------    ---------    -----------
<S>                                                          <C>             <C>          <C>
Units....................................................     $     0.45     4/16/2001     3/30/2001
Series A Preferred Units.................................     $  0.56125     3/15/2001      3/1/2001
Series B Preferred Units.................................     $  0.65625     2/15/2001      2/1/2001
Series C Preferred Units.................................     $0.5390625     3/15/2001      3/1/2001
</TABLE>

NOTE 7 -- CUMULATIVE EFFECT OF A CHANGE IN ACCOUNTING PRINCIPLE

     In June 1998, the FASB issued Statement No. 133 "Accounting for Derivative
Instruments and Hedging Activities." The statement requires recording all
derivative instruments as assets or liabilities, measured at fair value.
Derivatives that are not hedges must be adjusted to fair value through income.
If the derivative is a hedge, depending on the nature of the hedge, changes in
the fair value of derivatives will either be offset against the hedge in fair
value of the hedged assets, liabilities, or firm commitments through earnings or
recognized in other comprehensive income until the hedged item is recognized in
earnings. The ineffective portion of a derivative's change in fair value will be
immediately recognized in earnings. The standard's effective date was deferred
by FASB Statement No. 137 to all fiscal years beginning after June 15, 2000. EOP
Partnership adopted the standard on January 1, 2001, and recorded a cumulative
effect of a change in accounting principle resulting in a loss of approximately
$1.1 million in connection with EOP Partnership's share of the cumulative effect
of a change in accounting principle recorded on an interest rate cap in place at
a property held through a joint venture.

                                        9
<PAGE>   10

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

NOTE 8 -- EARNINGS PER UNIT

     The following table sets forth the computation of basic and diluted
earnings per Unit and unit equivalent:

<TABLE>
<CAPTION>
                                                                FOR THE THREE MONTHS ENDED
                                                                        MARCH 31,
                                                                --------------------------
        (DOLLARS IN THOUSANDS, EXCEPT PER UNIT DATA)               2001           2000
------------------------------------------------------------    -----------    -----------
<S>                                                             <C>            <C>
NUMERATOR:
  Net income available for Units before net gain on sales of
     real estate, extraordinary items and cumulative effect
     of a change in accounting principle....................    $   138,280    $   100,773
  Net gain on sales of real estate..........................             --          3,862
  Extraordinary items.......................................             --           (611)
  Cumulative effect of a change in accounting principle.....         (1,142)            --
                                                                -----------    -----------
Numerator for basic and diluted earnings per Unit -- net
  income available for Units and unit equivalents...........    $   137,138    $   104,024
                                                                ===========    ===========
DENOMINATOR:
  Denominator for basic earnings per Unit -- weighted
     average Units outstanding..............................    348,476,502    281,380,638
  Effect of dilutive securities:
     Units issuable upon exercise of Equity Office share
      Options, put options and restricted shares............      2,924,351      2,188,010
                                                                -----------    -----------
  Denominator for diluted earnings per Unit -- adjusted
     weighted average Units and unit equivalents
     outstanding............................................    351,400,853    283,568,648
                                                                ===========    ===========
BASIC EARNINGS AVAILABLE FOR UNITS PER WEIGHTED AVERAGE
  UNIT:
  Net income before net gain on sales of real estate,
     extraordinary items and cumulative effect of a change
     in accounting principle................................    $      0.40    $      0.36
  Net gain on sales of real estate..........................             --           0.01
  Extraordinary items.......................................             --             --
  Cumulative effect of a change in accounting principle.....          (0.01)            --
                                                                -----------    -----------
  Net income................................................    $      0.39    $      0.37
                                                                ===========    ===========
DILUTED EARNINGS AVAILABLE FOR UNITS AND UNIT EQUIVALENTS
  PER WEIGHTED AVERAGE UNITS AND UNIT EQUIVALENTS:
  Net income before net gain on sales of real estate,
     extraordinary items and cumulative effect of a change
     in accounting principle................................    $      0.39    $      0.36
  Net gain on sales of real estate..........................             --           0.01
  Extraordinary items.......................................             --             --
  Cumulative effect of a change in accounting principle.....             --             --
                                                                -----------    -----------
  Net income................................................    $      0.39    $      0.37
                                                                ===========    ===========
</TABLE>

                                        10
<PAGE>   11

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

     The following securities were not included in the computation of diluted
earnings per Unit and unit equivalent since they would have an antidilutive
effect:

<TABLE>
<CAPTION>
                                                                           FOR THE THREE MONTHS ENDED
                                                                                    MARCH 31,
                                                        WEIGHTED AVERAGE   ---------------------------
               ANTIDILUTIVE SECURITIES                   EXERCISE PRICE        2001           2000
------------------------------------------------------  ----------------   ------------   ------------
<S>                                                     <C>                <C>            <C>
Share options.........................................      $30.340          3,077,389             --
Share options.........................................      $30.030                 --      3,396,317
Series B Preferred Units..............................      $35.700          6,000,000      6,000,000
Warrants..............................................      $39.375          5,000,000      5,000,000
                                                                            ----------     ----------
          Total.......................................                      14,077,389     14,396,317
                                                                            ==========     ==========
</TABLE>

NOTE 9 -- SEGMENT INFORMATION

     As discussed in Note 1, EOP Partnership's primary business is the ownership
and operation of Office Properties. EOP Partnership's long-term tenants are in a
variety of businesses and no single tenant is significant to EOP Partnership's
business. The Property Operating Revenues generated at the Corporate and Other
segment consist of revenues earned by the Parking Facilities primarily from the
rental of parking spaces. The Other Revenues generated at the Corporate and
Other segment consist primarily of fee income from the management of office
properties owned by third parties and interest and dividend income on various
investments. Information related to this segment for the three months ended
March 31, 2001 and 2000 is below:

<TABLE>
<CAPTION>
                                                          FOR THE THREE MONTHS ENDED MARCH 31, 2001
                                                          -----------------------------------------
                                                             OFFICE      CORPORATE
                 (DOLLARS IN THOUSANDS)                    PROPERTIES    AND OTHER    CONSOLIDATED
--------------------------------------------------------  ------------   ----------   -------------
<S>                                                       <C>            <C>          <C>
Property Operating Revenues.............................  $   645,462    $   4,747     $   650,209
Property Operating Expenses.............................     (213,415)      (1,176)       (214,591)
                                                          -----------    ---------     -----------
  Net operating income..................................      432,047        3,571         435,618
                                                          -----------    ---------     -----------
Adjustments to arrive at net income:
  Other revenues........................................        1,133       11,874          13,007
  Interest expense(1)...................................      (52,600)    (105,340)       (157,940)
  Depreciation and amortization.........................     (118,531)      (6,443)       (124,974)
  Ground rent...........................................       (3,081)          --          (3,081)
  General and administrative............................          (47)     (25,592)        (25,639)
                                                          -----------    ---------     -----------
  Total adjustments to arrive at net income.............     (173,126)    (125,501)       (298,627)
                                                          -----------    ---------     -----------
Income before allocation to minority interests, income
  from investment in unconsolidated joint ventures and
  cumulative effect of a change in accounting
  principle.............................................      258,921     (121,930)        136,991
Minority interests......................................       (3,253)          --          (3,253)
Income from investment in unconsolidated joint
  ventures..............................................       15,208          218          15,426
Cumulative effect of a change in accounting principle...       (1,142)          --          (1,142)
                                                          -----------    ---------     -----------
Net income..............................................  $   269,734    $(121,712)    $   148,022
                                                          ===========    =========     ===========
Capital and tenant improvements.........................  $    47,746    $   6,164     $    53,910
                                                          ===========    =========     ===========
Total Assets............................................  $18,122,318    $ 600,980     $18,723,298
                                                          ===========    =========     ===========
</TABLE>

                                        11
<PAGE>   12

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

<TABLE>
<CAPTION>
                                                                    FOR THE THREE MONTHS ENDED
                                                                          MARCH 31, 2000
                                                              ---------------------------------------
                                                                OFFICE      CORPORATE
                   (DOLLARS IN THOUSANDS)                     PROPERTIES    AND OTHER    CONSOLIDATED
------------------------------------------------------------  ----------    ---------    ------------
<S>                                                           <C>           <C>          <C>
Property Operating Revenues.................................  $ 450,992     $  9,944      $ 460,936
Property Operating Expenses.................................   (152,646)      (2,691)      (155,337)
                                                              ---------     --------      ---------
  Net operating income......................................    298,346        7,253        305,599
                                                              ---------     --------      ---------
Adjustments to arrive at net income:
  Other revenues............................................      2,918        5,021          7,939
  Interest expense(1).......................................    (27,505)     (73,027)      (100,532)
  Depreciation and amortization.............................    (85,457)      (4,195)       (89,652)
  Ground rent...............................................     (2,011)         (13)        (2,024)
  General and administrative................................       (112)     (19,539)       (19,651)
                                                              ---------     --------      ---------
  Total adjustments to arrive at net income.................   (112,167)     (91,753)      (203,920)
                                                              ---------     --------      ---------
Income before allocation to minority interests, income from
  investment in unconsolidated joint ventures, net gain on
  sales of real estate and extraordinary items..............    186,179      (84,500)       101,679
Minority interests..........................................       (438)        (115)          (553)
Income from investment in unconsolidated joint ventures.....     11,361           13         11,374
Net gain on sales of real estate............................      3,862           --          3,862
Extraordinary items.........................................       (611)          --           (611)
                                                              ---------     --------      ---------
Net income..................................................  $ 200,353     $(84,602)     $ 115,751
                                                              =========     ========      =========
Capital and tenant improvements.............................  $  45,348     $  4,677      $  50,025
                                                              =========     ========      =========
</TABLE>

---------------
(1) Interest expense for the Office Properties does not include an allocation of
    interest expense on corporate unsecured debt.

NOTE 10 -- PENDING MERGER WITH SPIEKER PROPERTIES, INC.

     On February 22, 2001, Equity Office and Spieker Properties, Inc.
("Spieker") entered into a merger agreement in which Spieker will merge into
Equity Office and Spieker Properties, L.P. ("Spieker Partnership"), Spieker's
operating partnership subsidiary, will merge into EOP Partnership (the "Spieker
Merger"). The transaction values Spieker (including the outside interests in
Spieker Partnership) at approximately $7.3 billion, which includes transaction
costs and the assumption of approximately $2.1 billion in debt and $356.3
million in preferred stock and partnership units. EOP Partnership will pay
approximately $1.2 billion in cash and issue approximately 117.7 million new EOP
Partnership Units and 14.3 million new EOP Partnership preferred units in the
transaction. EOP Partnership intends to finance the $1.2 billion cash portion of
the purchase price using a combination of available borrowing capacity under the
line of credit and a new bridge loan facility to be entered into before the
closing of the merger. In May 2001, Equity Office received a commitment for an
$815 million bridge loan facility (subject to increase to $1.0 billion upon
execution of the commitment by the remaining three participant banks) with a
term of 364 days at an interest rate based on LIBOR plus 80 basis points,
subject to Equity Office's credit rating.

     Following the Spieker Merger, EOP Partnership is expected to own and
operate approximately 124 million square feet of office space nationwide, which
includes 25 million square feet of office space attributable to Spieker. EOP
Partnership is expected to acquire Spieker's industrial portfolio of
approximately 12.7 million square feet and its development properties totaling
approximately 1.7 million square feet.
                                        12
<PAGE>   13

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

     Upon completion of the Spieker Merger, Equity Office will expand its Board
of Trustees from 13 to 16 members. The new members will be Warren E. Spieker,
Jr., chairman of Spieker, and Co-Chief Executive Officers Craig G. Vought and
John A. Foster.

     The Spieker Merger, which will be accounted for using purchase accounting,
is subject to the approval of the shareholders of Equity Office and Spieker and
the partners of EOP Partnership and Spieker Partnership, as applicable, and to
other customary conditions.

NOTE 11 -- COMMITMENTS AND CONTINGENCIES

  Concentration of Credit Risk

     EOP Partnership maintains its cash and cash equivalents at financial
institutions. The combined account balances at each institution typically exceed
FDIC insurance coverage and, as a result, there is a concentration of credit
risk related to amounts on deposit in excess of FDIC insurance coverage.
Management of EOP Partnership believes that the risk is not significant.

  Environmental

     EOP Partnership, as an owner of real estate, is subject to various
environmental laws of federal and local governments. Compliance by EOP
Partnership with existing laws has not had a material adverse effect on EOP
Partnership's financial condition and results of operations, and management does
not believe it will have such an impact in the future. However, EOP Partnership
cannot predict the impact of new or changed laws or regulations on its current
Properties or on properties that it may acquire in the future.

  Litigation

     Neither EOP Partnership nor any of its Properties is presently subject to
material litigation nor, to EOP Partnership's knowledge, is any litigation
threatened against EOP Partnership or any of the Properties, other than routine
actions for negligence and other claims and administrative proceedings arising
in the ordinary course of business, some of which are expected to be covered by
liability insurance and all of which collectively are not expected to have a
material adverse effect on the liquidity, results of operations, or business or
financial condition of EOP Partnership.

  Insurance

     EOP Partnership is self-insured for certain amounts related to losses that
may be incurred at the Properties and has third party insurance coverage for
specified amounts above the deductible amounts. However, management does not
believe that this exposure will have a material adverse effect on EOP
Partnership.

     EOP Partnership carries earthquake insurance on all of the Properties,
including those located in California, subject to coverage limitations which EOP
Partnership believes are commercially reasonable. In light of the California
earthquake risk, California building codes since the early 1970s have
established construction standards for all new buildings. The current and
strictest construction standards were adopted in 1987. Of the 103 Properties
located in California, 19 have been built since January 1, 1988, and EOP
Partnership believes that all of the Properties were constructed in full
compliance with the applicable standards existing at the time of construction.
No assurance can be given that material losses in excess of insurance proceeds
will not occur in the future.

                                        13
<PAGE>   14

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
                                  (UNAUDITED)

  Commitments

     In accordance with the agreement governing the investment in Wright Runstad
Associates Limited Partnership ("WRALP"), EOP Partnership agreed to make
available to WRALP up to $20.0 million in additional financing or credit support
for future development. As of March 31, 2001, no amounts have been funded
pursuant to this agreement. However, EOP Partnership has guaranteed WRALP's line
of credit, which has an outstanding balance of approximately $16.3 million as of
March 31, 2001.

  Contingencies

     Certain Properties owned in joint ventures with unaffiliated parties have
buy/sell options that may be exercised to acquire the other partner's interest
by either EOP Partnership or its joint venture partner if certain conditions are
met as defined in the respective joint venture agreement.

     In connection with the acquisition of certain Properties, EOP Partnership
has agreed not to sell such Properties in a taxable transaction for a period of
time as defined in their respective agreements, or EOP Partnership may be
obligated to make additional payments to the respective sellers.

     The holders of the Wright Runstad & Company options (the "WR Holders")
exercised their option to extend the date to August 13, 2001 at which time the
WR Holders can require Equity Office to purchase all or a portion of the
remaining 1,717,844 Common Shares issued to them at a price equal to $31.50 per
Common Share. Prior to such date, if the WR Holders sell all or a portion of
their Common Shares to a third party for a price less than $29.10625, then
Equity Office is obligated to pay to the WR Holders for each Common Share sold
at such lower price an amount equal to the difference between $29.10625 and such
lower price, not to exceed $3.00 per Common Share. Any amounts paid by Equity
Office as a result of such sales will result in EOP Partnership making an equal
payment to Equity Office and will be recorded as a reduction in partners'
capital. For put options exercised on August 13, 2001, any amounts paid up to
$29.10625 per Common Share would be reflected as a reduction in partners'
capital and the portion of any amounts paid in excess of $29.10625 per Common
Share (not to exceed $2.39375 per Common Share up to an aggregate of
approximately $4.1 million) would be reflected as a put option settlement. The
$4.1 million portion of the total potential payment has been reflected as a put
option settlement on a straight-line basis over the period between August 13,
1999 and August 13, 2000.

     In connection with the acquisition of Worldwide Plaza on October 1, 1998,
EOP Partnership issued a transferable put option on the 6,861,166 Units issued
in the transaction, which is exercisable only on the third anniversary of
closing with an estimated fair value of approximately $27.4 million. This option
entitles its holder to additional Common Shares, the number of which shall be
determined using a formula based on the extent, if any, that the Common Shares
are then trading at less than $29.05 per share.

NOTE 12 -- SUBSEQUENT EVENTS

1. On April 30, 2001, EOP Partnership acquired the remaining 33.3% interest in
   the 120 Montgomery Office Property from an unaffiliated party for
   approximately $23.8 million. The mortgage note encumbering the Property was
   prepaid. The total payoff was approximately $47.5 million, which included
   accrued interest of approximately $.2 million.

2. EOP Partnership has an equity investment in Broadband Office, Inc., a
   facilities based provider of broadband data, video and voice communication
   services delivered over fiber optic networks. In May 2001, Broadband Office,
   Inc. filed for Chapter 11 bankruptcy protection. The management of EOP
   Partnership believes that any potential loss in its investment in Broadband
   will not have a material adverse effect on the financial condition of EOP
   Partnership.

                                        14
<PAGE>   15

ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS.

OVERVIEW

     The following discussion and analysis of the consolidated financial
condition and consolidated results of operations should be read together with
the consolidated financial statements of EOP Partnership and notes thereto
contained in this Form 10-Q. Terms employed herein as defined terms, but without
definition, shall have the meaning set forth in the notes to the financial
statements. Statements contained in this "Management's Discussion and Analysis
of Financial Condition and Results of Operations," including, without
limitation, the "Market Risk" and "Developments" disclosures, which are not
historical fact may be forward-looking statements. Such statements (none of
which is intended as a guarantee of performance) are subject to certain risks
and uncertainties, which could cause actual results to differ materially from
those projected or anticipated. Readers are cautioned not to place undue
reliance on these forward-looking statements, which speak only as of March 31,
2001. Among the factors that EOP Partnership has made assumptions are the
following:

     - Future economic conditions which may have an impact upon the demand for
       office space and tenant ability to pay rent, either at current or at
       increased levels (including, without limitation, changes in
       macro-economic conditions and the demand for office space in California
       and other West Coast markets in which Spieker Properties has a
       substantial presence, as well as the nationwide markets in which EOP
       Partnership has a presence);

     - Equity Office's ability to merge successfully the operations of Spieker
       Properties into the Equity Office organization;

     - Prevailing interest rates;

     - Extent of any inflation on operating expenses;

     - EOP Partnership's ability to reduce various expenses as a percentage of
       revenues;

     - EOP Partnership's continuing ability to pay amounts due to its
       noteholders and preferred Unitholders before any distribution to holders
       of Units;

     - Costs to complete and lease-up pending developments;

     - EOP Partnership's continued access to adequate credit facilities or other
       debt financing on acceptable terms, including amounts required for the
       Spieker Merger; and

     - Demand from EOP Partnership's customers for office-related services.

     During the three months ended March 31, 2001, EOP Partnership completed the
following key transactions:

     - Sold Warner Park Center for approximately $8.95 million;

     - Paid-off approximately $120.8 million of mortgage debt encumbering
       several Office Properties.

SPIEKER MERGER

     On February 22, 2001, Equity Office and Spieker entered into a merger
agreement in which Spieker will merge into Equity Office and Spieker Partnership
will merge into EOP Partnership. The transaction values Spieker (including the
outside interests in Spieker Partnership) at approximately $7.3 billion, which
includes transaction costs and the assumption of approximately $2.1 billion in
debt and $356.3 million in preferred stock and partnership units. EOP
Partnership will pay approximately $1.2 billion in cash and issue approximately
117.7 million new EOP Partnership Units and 14.3 million new EOP Partnership
preferred units in the transaction. EOP Partnership intends to finance the $1.2
billion cash portion of the purchase price using a combination of available
borrowing capacity under the line of credit and a new bridge loan facility to be
entered into before the closing of the merger. In May 2001, Equity Office
received a commitment for an $815 million bridge loan facility (subject to
increase to $1.0 billion upon execution of the commitment by the

                                        15
<PAGE>   16

remaining three participant banks) with a term of 364 days at an interest rate
based on LIBOR plus 80 basis points, subject to EOP Partnership's credit rating.

     Following the Spieker Merger, EOP Partnership is expected to own and
operate approximately 124 million square feet of office space nationwide, which
includes approximately 25 million square feet of office space attributable to
Spieker. EOP Partnership is expected to acquire Spieker's industrial portfolio
of approximately 12.7 million square feet and its development properties
totaling approximately 1.7 million square feet.

RESULTS OF OPERATIONS

  GENERAL

     The following discussion is based primarily on the consolidated financial
statements of EOP Partnership as of March 31, 2001 and for the three months
ended March 31, 2001 and 2000.

     EOP Partnership receives income primarily from rental revenue from the
Office Properties, including reimbursements from tenants for certain operating
costs, and from parking revenue from Office Properties and Parking Facilities.
During the three months ended March 31, 2001, there was an increase in overall
vacancy rates and sublease space for office properties in many of Equity
Office's markets due to the current slowdown in economic activity. Despite the
increase in overall vacancy rates and sublease space, Equity Office's weighted
average occupancy rate was substantially unchanged at 94.2% at March 31, 2001,
compared to 94.6% at December 31, 2000. Market rents also have declined in
certain of Equity Office's markets. Although Class A office properties, such as
those owned by Equity Office, historically have outperformed Class B and Class C
office properties during periods of declining economic activity, there can be no
assurance that vacancy rates, sublease space and market rents will stabilize at
their current levels. Further increases in overall vacancy rates and sublease
space and/or further declines in market rents could adversely affect Equity
Office's occupancy rate, the market rents it can charge on expiring leases and
its revenues and operating results in subsequent periods.

     Below is a summary of EOP Partnership's acquisition and disposition
activity since January 1, 2000. The buildings and total square feet shown
include Properties EOP Partnership owns in joint ventures with other partners
and reflects the total square footage of the Properties. Excluding the joint
venture partners' share of the square feet of these Properties, EOP Partnership
effectively owned 92.7 million square feet of office space as of March 31, 2001.

<TABLE>
<CAPTION>
                                                                OFFICE PROPERTIES
                                                            -------------------------    PARKING FACILITIES
                                                                         TOTAL SQUARE    -------------------
                                                            BUILDINGS        FEET        GARAGES     SPACES
                                                            ---------    ------------    --------    -------
<S>                                                         <C>          <C>             <C>         <C>
Properties owned as of:
January 1, 2000.........................................       294        77,015,610        20       20,506
  Acquisitions..........................................        85        20,980,290        --           --
  Developments placed in service........................         9         1,843,653        --           --
  Dispositions..........................................        (7)         (964,136)      (11)      (6,992)
  Building remeasurements...............................        --           120,577        --          730
                                                               ---        ----------       ---       ------
December 31, 2000.......................................       381        98,995,994         9       14,244
  Dispositions..........................................        (1)          (58,183)       --           --
  Building remeasurements...............................        --            44,568        --           --
                                                               ---        ----------       ---       ------
March 31, 2001 ("Total Portfolio")......................       380        98,982,379         9       14,244
                                                               ===        ==========       ===       ======
</TABLE>

     As a result of the acquisition and disposition of properties, the financial
data presented shows changes in revenues and expenses from period-to-period.
Therefore, EOP Partnership does not believe its period-to-period financial data
are necessarily comparable. The following analysis shows changes resulting from
Properties that were held during the entire period for the periods being
compared (the "Core Portfolio") and the changes in the Total Portfolio.

                                        16
<PAGE>   17

     As reflected in the tables below, property revenues include rental
revenues, reimbursements from tenants for certain expenses, parking revenue,
Access services revenue and other property operating revenues. Property
operating expenses include real estate taxes, insurance, repairs and maintenance
and other property operating expenses.

 COMPARISON OF THE THREE MONTHS ENDED MARCH 31, 2001 TO MARCH 31, 2000

     The table below represents selected operating information for the Total
Portfolio and for the Core Portfolio consisting of 288 Office Properties and
nine Parking Facilities acquired or placed in service on or prior to January 1,
2000.

<TABLE>
<CAPTION>
                                            TOTAL PORTFOLIO                             CORE PORTFOLIO
                               -----------------------------------------   -----------------------------------------
                                                     INCREASE/      %                            INCREASE/      %
(DOLLARS IN THOUSANDS)           2001       2000     (DECREASE)   CHANGE     2001       2000     (DECREASE)   CHANGE
-----------------------------  --------   --------   ----------   ------   --------   --------   ----------   ------
<S>                            <C>        <C>        <C>          <C>      <C>        <C>        <C>          <C>
Property revenues............  $650,209   $460,936    $189,273     41.1%   $467,563   $441,646    $25,917        5.9%
Fee income...................     2,172      2,235         (63)    (2.8)         --         --         --         --
Interest/dividend income.....    10,835      5,704       5,131     90.0         827        517        310       60.0
                               --------   --------    --------    ------   --------   --------    -------     ------
      Total revenues.........   663,216    468,875     194,341     41.4     468,390    442,163     26,227        5.9
                               --------   --------    --------    ------   --------   --------    -------     ------
Interest expense.............   157,940    100,532      57,408     57.1      32,477     30,256      2,221        7.3
Depreciation and
  amortization...............   124,974     89,652      35,322     39.4      91,302     83,259      8,043        9.7
Property operating
  expenses...................   214,591    155,337      59,254     38.1     160,056    149,565     10,491        7.0
Ground rent..................     3,081      2,024       1,057     52.2       2,733      2,024        709       35.0
General and administrative...    25,639     19,651       5,988     30.5          (8)       (17)         9      (52.9)
                               --------   --------    --------    ------   --------   --------    -------     ------
      Total expenses.........   526,225    367,196     159,029     43.3     286,560    265,087     21,473        8.1
                               --------   --------    --------    ------   --------   --------    -------     ------
Income before allocation to
  minority interests, income
  from investment in
  unconsolidated joint
  ventures, net gain on sales
  of real estate,
  extraordinary items and
  cumulative effect of a
  change in accounting
  principle..................   136,991    101,679      35,312     34.7     181,830    177,076      4,754        2.7
Minority interests...........    (3,253)      (553)     (2,700)   488.2      (1,095)      (438)      (657)     150.0
Income from investment in
  unconsolidated joint
  ventures...................    15,426     11,374       4,052     35.6      12,001     10,008      1,993       19.9
Net gain on sales of real
  estate.....................        --      3,862      (3,862)   (100.0)        --         --         --         --
Extraordinary items..........        --       (611)        611    (100.0)        --       (611)       611     (100.0)
Cumulative effect of a change
  in accounting principle....    (1,142)        --      (1,142)      --          --         --         --         --
                               --------   --------    --------    ------   --------   --------    -------     ------
Net income...................  $148,022   $115,751    $ 32,271     27.9%   $192,736   $186,035    $ 6,701        3.6%
                               ========   ========    ========    ======   ========   ========    =======     ======
Property revenues less
  property operating expenses
  before depreciation and
  amortization, general and
  administrative, ground rent
  and interest expense.......  $435,618   $305,599    $130,019     42.5%   $307,507   $292,081    $15,426        5.3%
                               ========   ========    ========    ======   ========   ========    =======     ======
Net deferred rental
  revenue....................  $ 14,324   $ 12,206    $  2,118     17.4%   $  8,094   $ 11,804    $(3,710)     (31.4)%
                               ========   ========    ========    ======   ========   ========    =======     ======
Lease termination fees.......  $  6,750   $  7,228    $   (478)    (6.6)%  $  1,342   $  7,205    $(5,863)     (81.4)%
                               ========   ========    ========    ======   ========   ========    =======     ======
</TABLE>

  Property Revenues

     The increase in property revenues in the Core Portfolio resulted from an
increase in rental rates and a slight increase in occupancy. The weighted
average occupancy of the Core Portfolio increased from 93.9% at January 1, 2000
to 94.1% at March 31, 2001, mainly due to tenant rollover at various Properties.
Included in Property Revenues are lease termination fees. These fees relate to
specific tenants, each of whom has paid a fee to terminate its lease obligations
before the end of the contractual term of the lease. Although EOP

                                        17
<PAGE>   18

Partnership has historically experienced similar levels of such termination
fees, there is no way of predicting the timing or amounts of future lease
termination fees.

  Interest/Dividend Income

     Total Portfolio interest/dividend income increased primarily as a result of
a $75 million investment in May 2000 in Series A Convertible Cumulative
Preferred Stock (the "HQ Series A Preferred Stock") of HQ Global Workplaces,
Inc. ("HQ"). The HQ Series A Preferred Stock has an initial dividend rate of
13.5% per annum, which increases by 50 basis points each year through maturity
in 2007.

  Interest Expense

     Total Portfolio interest expense increased from the prior period as a
result of having a higher average outstanding debt balance as compared to the
prior period, mainly as a result of the Cornerstone Merger, and an increase in
the weighted average interest rate. In addition, the following statistics for
each period for the Total Portfolio are as follows:

     - Total debt to total assets increased to 46.2% from 42.3%;

     - Interest coverage ratio decreased to 2.7 times from 3.0 times; and

     - Weighted average interest rate increased to 7.5% from 7.3%.

     Core Portfolio interest expense increased from the prior period due to the
financing of Park Avenue Tower and 850 Third Avenue partially offset by the
paydown of mortgage debt on certain Properties. Interest expense on unsecured
notes and the line of credit are not reflected in the Core Portfolio.

  Depreciation and Amortization

     Total portfolio depreciation and amortization expense increased from the
prior period as a result of Properties acquired and capital and tenant
improvements made during the periods. Core Portfolio depreciation and
amortization expense increased as a result of capital and tenant improvements
made during the periods.

  Property Operating Expenses

     Core Portfolio property operating expenses increased mainly as a result of
increases in utilities, primarily electricity, and repairs and maintenance.
Utilities increased approximately $5.4 million consisting mostly of electricity
expense and repairs and maintenance increased approximately $3.6 million
primarily due to higher wages and increases in contract services. Management has
noted the potential for further increases in utility costs as a result of
service disruptions that have occurred in California and may occur elsewhere.
Substantially all of the office leases require the tenant to pay, as additional
rent, a portion of any increases in operating expenses over a base amount.
Equity Office believes the majority of any increase in expenses will be offset,
in part, by expense reimbursements from tenants.

  General and Administrative Expenses

     General and administrative expenses increased due to an increase in the
number of employees at the corporate and regional offices mainly as a result of
hiring additional personnel due to the Cornerstone Merger, which was
anticipated, and an increase in franchise and income taxes at certain
properties. Although general and administrative expenses are subject to increase
along with any increase in the size of the portfolio, it is also anticipated
that economies of scale may be realized with future growth, should it occur.

  Income from Investment in Unconsolidated Joint Ventures

     Income from investment in unconsolidated joint ventures increased for the
Total Portfolio due to the acquisition of an interest in 1301 Avenue of the
Americas office property in August 2000 and the partial sale of two Office
Properties in June 2000. EOP Partnership retained an equity interest in the
Office Properties that

                                        18
<PAGE>   19

were partially sold and accounts for its remaining interests under the equity
method of accounting. Prior to the sale, the results of operations of such
Office Properties were consolidated.

ACCESS INCOME

     EOP Partnership generates additional income by providing its tenants with
access to services and by investments in companies that provide tenant services.
Below is a table summarizing this income:

<TABLE>
<CAPTION>
                                                                 FOR THE THREE
                                                                  MONTHS ENDED
                                                                   MARCH 31,
                                                                ----------------
                   (DOLLARS IN THOUSANDS)                        2001      2000
------------------------------------------------------------    ------    ------
<S>                                                             <C>       <C>
REVENUES:
OTHER INCOME
  Access services(1)........................................    $3,238    $2,034
  Amortization of deferred revenue(2).......................       533     1,036
INTEREST/DIVIDEND INCOME
  HQ Global Workplaces, Inc.................................     3,084        --
INCOME FROM UNCONSOLIDATED JOINT VENTURES
  Regus Equity Business Centers(3)..........................       432      (376)
  Access Services...........................................       327       129
                                                                ------    ------
  Total Access Income.......................................    $7,614    $2,823
                                                                ======    ======
</TABLE>

---------------
(1) Amounts reflected for Access services include income from the following:
    Telecom, Adcom, ATMs, Equity Health Clubs, Book Fairs and Vending.

(2) EOP Partnership received common stock and/or warrants to purchase common
    stock for allowing companies that provide telecommunication and other
    services access to EOP Partnership Properties. The securities received from
    these companies were recorded as deferred revenue at fair value at the time
    such securities were earned and are included in other liabilities on the
    balance sheet. The deferred revenue will be amortized into other income over
    the terms of the respective license agreements.

(3) EOP Partnership indirectly owns a 50% membership interest in this joint
    venture. The joint venture provides fully furnished offices under
    short-term, flexible rental agreements to prospective tenants seeking this
    type of office space.

PROPERTY DISPOSITIONS

     EOP Partnership has disposed or partially disposed of the following office
properties and parking facilities since January 1, 2000:

<TABLE>
<CAPTION>
 YEAR                       OFFICE PROPERTIES                                      PARKING FACILITIES(3)
 ----   --------------------------------------------------------- -------------------------------------------------------
<S>     <C>                          <C>                          <C>                         <C>
2001... Warner Park Center
2000... Bank of America Tower(1)     Agoura Hills Business Park   1111 Sansom Street Garage   Capital Common Garage
        Sarasota City Center         Westlake Spectrum Center I & 15th & Sansom Street        Forbes and Allies Garage(4)
        Media Center(2)              II                           1602-34 Chancellor Garage   Juniper/Locust Garage
        Park Plaza                   Westwood Business Centre     1616 Sansom Street Garage   Milwaukee Center Garage
                                     500 Marquette Building       Boston Harbor Garage        Riverfront Center
</TABLE>

---------------
(1) This Office Property was partially sold. EOP Partnership accounts for its
    remaining interest in this Office Property under the equity method of
    accounting.

(2) Media Center was a development site.

(3) These 11 parking facilities were disposed of on May 17, 2000.

(4) Consists of two parking facilities.

                                        19
<PAGE>   20

     Below is a summary of the results of these properties through their
respective disposition dates:

<TABLE>
<CAPTION>
                                                                FOR THE THREE MONTHS
                                                                  ENDED MARCH 31,
                                                                --------------------
                   (DOLLARS IN THOUSANDS)                       2001          2000
------------------------------------------------------------    -----       --------
<S>                                                             <C>         <C>
Property revenues...........................................    $236        $19,214
Interest income.............................................       2             11
                                                                ----        -------
       Total revenues.......................................     238         19,225
                                                                ----        -------
Interest expense............................................      --            127
Depreciation and amortization...............................       8          3,949
Property operating expenses.................................     (92)         5,571
General and administrative..................................       4            128
                                                                ----        -------
       Total expenses.......................................     (80)         9,775
                                                                ----        -------
Income before allocation to minority interests and net gain
  on sales of real estate...................................     318          9,450
Minority interest -- partially owned properties.............      --           (115)
Net gain on sales of real estate............................      --          3,862
                                                                ----        -------
Net income..................................................    $318        $13,197
                                                                ====        =======
Property revenues less property operating expenses before
  depreciation and amortization, general and administrative
  and interest expense......................................    $328        $13,643
                                                                ====        =======
</TABLE>

LIQUIDITY AND CAPITAL RESOURCES

  Liquidity

     Net cash from operations represents the primary source of liquidity to fund
distributions, debt service, recurring capital costs and non-revenue enhancing
tenant improvements. EOP Partnership's partnership agreement generally requires
EOP Partnership to distribute substantially all of the net cash from operations
each quarter and to make reasonable efforts to distribute to Equity Office
enough cash for it to meet the 95% distribution requirement. EOP Partnership
expects that its line of credit will provide for temporary working capital, the
funding of capital improvements and revenue enhancing tenant improvements,
unanticipated cash needs and funding of acquisitions and development costs. EOP
Partnership currently intends to continue to make, but has not contractually
bound itself to make, regular quarterly distributions to holders of Units and
preferred units. Subject to the foregoing, EOP Partnership has established
annual distribution rates as follows:

     - $1.80 per annum per Unit;

     - 8.98% per annum ($2.245 per unit) for each Series A Preferred Unit;

     - 5.25% per annum ($2.625 per unit) for each Series B Preferred Unit; and

     - 8.625% per annum ($2.15625 per unit) for each Series C Preferred Unit.

     Since EOP Partnership's anticipated distributions will not allow EOP
Partnership, using only cash from operations, to retire all of its debt as it
comes due, EOP Partnership will be required to repay maturing debt with funds
from debt and/or equity financing. There can be no assurance that such financing
will be available on acceptable terms or at all.

  Debt Financing

     The table below summarizes the mortgage debt, unsecured notes and the line
of credit indebtedness at March 31, 2001 and December 31, 2000, including a net
unamortized discount on mortgage debt of $(19,056)

                                        20
<PAGE>   21

and $(17,825), respectively, and a net unamortized discount on unsecured notes
of $(3,596) and $(3,807), respectively, recorded in connection with property
acquisitions, mergers and the issuance of unsecured notes.

<TABLE>
<CAPTION>
                                                                MARCH 31,        DECEMBER 31,
(DOLLARS IN THOUSANDS)                                             2001              2000
------------------------------------------------------------    ----------       ------------
<S>                                                             <C>              <C>
DEBT SUMMARY:
Balance
  Fixed rate................................................    $8,537,314        $8,618,517
  Variable rate.............................................       120,845           184,477
                                                                ----------        ----------
          Total.............................................    $8,658,159        $8,802,994
                                                                ==========        ==========
Percent of total debt:
  Fixed rate................................................          98.6%             97.9%
  Variable rate.............................................           1.4%              2.1%
                                                                ----------        ----------
          Total.............................................         100.0%            100.0%
                                                                ==========        ==========
Effective interest rate at end of period:
  Fixed rate................................................           7.5%              7.5%
  Variable rate.............................................           6.3%              7.7%
                                                                ----------        ----------
          Effective interest rate...........................           7.5%              7.5%
                                                                ==========        ==========
</TABLE>

     The variable rate debt bears interest at an interest rate based on various
spreads over LIBOR.

MORTGAGE DEBT

     As of March 31, 2001, total mortgage debt (excluding EOP Partnership's
share of unconsolidated mortgage debt of approximately $835.9 million) consisted
of approximately $2.7 billion of fixed-rate debt with a weighted average
interest rate of approximately 7.8% and $83.3 million of variable rate debt
based on various spreads over LIBOR. EOP Partnership's mortgage debt at March
31, 2001 will mature as follows:

<TABLE>
<CAPTION>
                          (Dollars in thousands)
--------------------------------------------------------------------------
<S>                                                             <C>
2001........................................................    $   28,447
2002........................................................       177,504
2003........................................................       200,300
2004........................................................       325,446
2005........................................................       527,675
Thereafter..................................................     1,543,939
                                                                ----------
Subtotal....................................................     2,803,311
Net discount (net of accumulated amortization of $3.3
  million)..................................................       (19,056)
                                                                ----------
          Total.............................................    $2,784,255
                                                                ==========
</TABLE>

     The instruments encumbering the Properties restrict transfer of the
respective Properties subject to the terms of the mortgage, prohibit additional
liens and require payment of real estate taxes on the Properties, maintenance of
the Properties in good condition, maintenance of insurance on the Properties and
obtaining lender consent to material tenant leases.

LINE OF CREDIT

     EOP Partnership has a $1.0 billion revolving credit facility that was
obtained in May 2000 (the "Line of Credit"). The Line of Credit bears interest
at LIBOR plus 60 basis points and matures on June 19, 2003. There is also an
annual facility fee of $2.0 million payable quarterly. In addition, a
competitive bid option, whereby the lenders participating in the credit facility
bid on the interest to be charged, is available for up to $350 million of the
borrowings under the credit facility. As of May 4, 2001, there was approximately
$192.1 million outstanding on the Line of Credit.

                                        21
<PAGE>   22

     Equity Office has guaranteed the outstanding obligation under the Line of
Credit.

UNSECURED NOTES

     The table below summarizes EOP Partnership's unsecured notes outstanding as
of March 31, 2001:

<TABLE>
<CAPTION>
      TERM (IN YEARS)          MATURITY DATE      AMOUNT           NET PROCEEDS    STATED RATE    EFFECTIVE RATE(1)
      ---------------          -------------    ----------         ------------    -----------    -----------------
                                                    (Dollars in thousands)
<S>                            <C>              <C>                <C>             <C>            <C>
3..........................       1/15/02       $  200,000          $  198,593        6.38%             6.62%
4..........................       2/15/02          250,000(2)          252,225        6.38%             6.30%
5..........................       2/15/03          300,000             294,120        6.38%             6.76%
3..........................      11/15/03          400,000             397,874        7.38%             7.55%
5..........................       1/15/04          300,000             297,034        6.50%             6.71%
6..........................       6/15/04          250,000             247,269        6.50%             6.68%
7..........................        9/1/04           30,000              29,960        7.24%             7.26%
7..........................       2/15/05          400,000             388,089        6.63%             7.02%
8..........................        9/1/05           50,000              48,705        7.36%             7.69%
6..........................       3/15/06          500,000             493,531        8.38%             8.59%
9..........................        9/1/06           50,000              48,624        7.44%             7.74%
9..........................       6/15/07          300,000             299,957        6.76%             6.76%
10.........................        9/1/07           50,000              48,584        7.41%             7.70%
7..........................      11/15/07          600,000             593,374        7.75%             7.91%
10.........................       2/15/08          300,000             291,655        6.75%             7.01%
8..........................      11/15/08          325,000(3)          314,594        7.25%             7.64%
10.........................       1/15/09          500,000             493,942        6.80%             6.94%
10.........................        8/1/10          360,000             356,213        8.10%             8.22%
20.........................       2/15/18          250,000             234,881        7.25%             7.54%
30.........................       6/15/28          225,000             221,138        7.25%             7.31%
30.........................       4/19/29          200,000             196,842        7.50%             7.55%
                                                ----------          ----------        -----             -----
          Subtotal..........................     5,840,000          $5,747,204        7.16%             7.35%
                                                                    ==========        =====             =====
          Net discount (net of accumulated
            amortization $.5 million).......        (3,596)
                                                ----------
          Total.............................    $5,836,404
                                                ==========
</TABLE>

---------------
(1) Includes the cost of terminated interest rate protection agreements,
    offering and transaction costs and premiums and discounts on certain
    unsecured notes.

(2) The notes are subject to mandatory redemption and a remarketing agreement in
    2002 but do not mature until 2012.

(3) These notes are exchangeable into Common Shares at an exchange price of
    $34.00 per share, which is equal to an exchange rate of 29.4118 Common
    Shares per $1,000 principal amount of notes. If the closing price of a
    Common Share on the NYSE at the time a holder exercises its exchange right
    is less than the exchange price of $34.00, the holder will receive, in lieu
    of Common Shares, cash in an amount equal to 97% of the product of: (a) the
    number of Common Shares into which the principal amount of notes subject to
    such exercise would otherwise be exchangeable; and (b) such closing price
    per Common Shares. The notes were issued by EOP Partnership and are
    guaranteed by Equity Office. Upon exchange of a $1,000 note for common
    shares of Equity Office, EOP Partnership would issue a corresponding number
    of Units to Equity Office on a one-for-one basis.

     EOP Partnership filed a shelf registration statement, which was declared
effective by the SEC on August 31, 2000, relating to the issuance from time to
time of up to an additional $2.0 billion of unsecured debt securities and
warrants exercisable for debt securities in amounts, at initial prices and on
terms to be determined and at the time of the offering. In November 2000, EOP
Partnership issued $1.0 billion of unsecured notes under this registration
statement.

                                        22
<PAGE>   23

  Restrictions and Covenants

     Agreements or instruments relating to the unsecured notes and the Line of
Credit contain certain restrictions and requirements regarding total
debt-to-assets ratios, secured debt-to-total assets ratios, debt service
coverage ratios, minimum ratio of unencumbered assets to unsecured debt and
other limitations.

EQUITY SECURITIES

     A summary of the activity of Equity Office's Common Shares and EOP
Partnership's Units (exclusive of Units owned by Equity Office) during 2001 is
as follows:

<TABLE>
<CAPTION>
                                                          COMMON SHARES      UNITS          TOTAL
                                                          -------------    ----------    -----------
<S>                                                       <C>              <C>           <C>
Outstanding at January 1, 2001........................     306,966,596     42,060,891    349,027,487
  Units exchanged for Common Shares...................         898,746       (898,746)            --
  Share options exercised.............................         537,063             --        537,063
  Restricted shares issued/cancelled, net.............         598,066             --        598,066
  Common Shares issued in exchange for the conversion
     of 10,000 Series B Preferred Shares..............          14,005             --         14,005
  Common Shares issued through the Dividend
     Reinvestment Program.............................           1,743             --          1,743
  Units retired.......................................              --       (113,829)      (113,829)
Units issued in the final reproration of a property
  acquisition.........................................              --          7,930          7,930
                                                           -----------     ----------    -----------
Outstanding at March 31, 2001.........................     309,016,219     41,056,246    350,072,465
                                                           ===========     ==========    ===========
</TABLE>

INVESTMENT IN SECURITIES

     EOP Partnership owns equity interests in several companies that provide
communication services or amenities to tenants. The equity interests are in the
form of common or preferred stock, vested and unvested warrants to acquire
common stock and an interest in a limited liability company. These investments
are included in Other Assets on the Consolidated Balance Sheets. Below is a
summary of these investments as of March 31, 2001:

<TABLE>
<CAPTION>
                             SQUARE FEET                         CAPITAL       SHARES       WARRANTS        BOOK
COMPANY                    (IN MILLIONS)(B)       SYMBOL       INVESTMENT    RECEIVED(C)   RECEIVED(C)    VALUE(D)
-------                    ----------------   --------------   -----------   -----------   -----------   -----------
                                                               (Dollars in                               (Dollars in
                                                               thousands)                                thousands)
<S>                        <C>                <C>              <C>           <C>           <C>           <C>
Allied Riser Communication
  Corp. ..................        94               ARCC         $  2,199      2,688,520        90,224     $  4,400
Broadband Office, Inc.....        58          Privately Held       3,525      2,656,609            --        5,014
Captivate Network, Inc....        72          Privately Held      10,164      2,287,169     2,406,781       20,530
Cypress Communications....        17               CYCO              829        828,950       919,581          390
HQ Global Workplace.......        --          Privately Held      85,181      1,839,497       555,911       85,181
Constellation Real
  Technologies............        --          Privately Held       2,749             --            --        2,749
CenterBeam, Inc.(a).......        --          Privately Held       7,000        664,767        31,160        7,000
                                                                --------     ----------     ---------     --------
       Total..............                                      $111,647     10,965,512     4,003,657     $125,264
                                                                ========     ==========     =========     ========
</TABLE>

---------------
(a) EOP Partnership obtained $7.0 million of series C preferred stock of
    CenterBeam, a provider of subscription based computing services. In
    addition, EOP Partnership entered into a marketing services agreement for
    which EOP Partnership may receive CenterBeam warrants for promotion and
    referral of tenants to CenterBeam.

(b) The Square Feet (in millions) represents the portion of EOP Partnership's
    portfolio that is anticipated to be wired by each company in accordance with
    their respective agreements. These square footage amounts

                                        23
<PAGE>   24

    are subject to change upon the signing of additional licensing agreements.
    As of March 31, 2001, approximately 84% of EOP Partnership's portfolio was
    wired and operational by at least one of EOP Partnership's strategic
    telecommunications providers.

(c) Common/preferred shares and warrants received may include amounts allocable
    to joint venture partners. EOP Partnership may earn additional
    common/preferred shares or warrants based upon achieving certain thresholds
    in accordance with the respective investment agreements or upon the signing
    of additional license agreements for properties.

(d) EOP Partnership's investments in publicly traded companies are adjusted to
    reflect their current market values. EOP Partnership's investments in
    privately held entities were recorded at estimated fair values when the
    investment was made.

MARKET RISK

     Since December 31, 2000, there have been no material changes in the
information regarding market risk that was provided in EOP Partnership's Form
10-K for the year ended December 31, 2000.

CAPITAL EXPENDITURES AND TENANT IMPROVEMENTS

     Capital expenditures are categorized as follows:

     - Non-recurring capital improvements -- capital improvements completed in
       the year of acquisition and the following two years (which were planned
       at the time of acquisition) and major renovations that enhance the value
       of the Property (such as lobby renovation, roof replacement or
       significant renovations for ADA compliance);

     - Recurring capital expenditures -- capital improvements incurred that
       enhance the value of the Property that are not classified as
       non-recurring capital improvements (such as chiller replacement, elevator
       upgrades or replacement of furniture, fixtures and equipment);

     - Development costs -- all hard and soft costs associated with the
       development or redevelopment of a Property, including tenant
       improvements, leasing commissions and capitalized interest and operating
       costs until the Property is substantially complete and ready for its
       intended use;

     - Revenue enhancing tenant improvements and leasing commissions -- tenant
       improvements and leasing commissions incurred on space which is vacant at
       the time of acquisition or has been vacant for nine months or more; and

     - Non-revenue enhancing tenant improvements and leasing
       commissions -- tenant improvements and leasing commissions incurred in
       connection with the renewal or retenanting of currently leased space to
       maintain the revenue being generated by such space.

                                        24
<PAGE>   25

     The table below details the amounts incurred for each type of expenditure:

<TABLE>
<CAPTION>
                                                          FOR THE THREE MONTHS ENDED
(DOLLARS IN THOUSANDS, EXCEPT PER SQUARE FOOT AMOUNTS)          MARCH 31, 2001
------------------------------------------------------    --------------------------
<S>                                                       <C>
CAPITAL EXPENDITURES:
Development costs.................................                 $10,656
Non-recurring capital improvements................                 $ 5,135
Recurring capital expenditures....................                 $ 4,983
Recurring capital expenditures per weighted average
  square foot.....................................                 $   .05
TENANT IMPROVEMENTS AND LEASING COMMISSIONS:
(The amounts shown below represent the total tenant improvement and leasing
commissions for leases which commenced during the period, regardless of when such
costs were actually paid which is a more useful measure of the total Tenant
Improvements and Leasing Commissions cost for the period presented).
Revenue enhancing.................................                 $ 6,395
Per square foot leased............................                 $ 21.76
Non-revenue enhancing:
  Non-revenue enhancing -- renewals...............                 $13,758
  Per square foot leased..........................                 $ 11.05
  Non-revenue enhancing -- retenanted.............                 $23,065
  Per square foot leased..........................                 $ 13.37
                                                                   -------
Total non-revenue enhancing.......................                 $36,823
Per square foot leased............................                 $ 12.40
</TABLE>

DEVELOPMENTS

     EOP Partnership currently owns several Properties in various stages of
development or pre-development. These developments are funded with proceeds from
working capital and the credit facility. Specifically identifiable direct
acquisition, development and construction costs are capitalized including, where
applicable, salaries and related costs, real estate taxes, interest and certain
pre-construction costs essential to the development of a property. The
Properties under development as of March 31, 2001 are as follows:
<TABLE>
<CAPTION>
                                                                                            EOP PARTNERSHIP'S
                                                                              ---------------------------------------------
                        ESTIMATED                                                           COSTS                   TOTAL
                        PLACED IN                                             EFFECTIVE    INCURRED     TOTAL      PROJECT
                         SERVICE                       NUMBER OF    SQUARE    OWNERSHIP     AS OF     ESTIMATED   ESTIMATED
     WHOLLY-OWNED        DATE(A)        LOCATION       BUILDINGS     FEET     PERCENTAGE   3/31/01    COSTS(A)      COST
----------------------  ---------   -----------------  ---------   ---------  ----------   --------   ---------   ---------
                                                                                         (Dollars in thousands)
<S>                     <C>         <C>                <C>         <C>        <C>          <C>        <C>         <C>
Parkside Towers(b)....   4Q/2001    Foster City, CA        2         398,000     100%      $ 72,923   $132,100    $132,100
EJ Randolph II........   2Q/2002    McLean, VA             1         122,000     100%         8,156     35,700      35,700
                                                          --       ---------               --------   --------    --------
                                                           3         520,000               $ 81,079   $167,800    $167,800
                                                          ==       =========               ========   ========    ========

<CAPTION>

                         CURRENT
                        PERCENTAGE
     WHOLLY-OWNED         LEASED
----------------------  ----------

<S>                     <C>
Parkside Towers(b)....      96%
EJ Randolph II........     100%
                           ---
                            97%
                           ===
</TABLE>

                                        25
<PAGE>   26
<TABLE>
<CAPTION>
                                                                                      EOP PARTNERSHIP'S
                                                                              ---------------------------------
                                                                                            COSTS
                        ESTIMATED                                             EFFECTIVE    INCURRED                 TOTAL
                        PLACED IN                                             OWNERSHIP     AS OF       TOTAL      PROJECT
WILSON/ EQUITY OFFICE    SERVICE                       NUMBER OF    SQUARE    PERCENTAGE   3/31/01    ESTIMATED   ESTIMATED
   DEVELOPMENTS(C)       DATE(D)        LOCATION       BUILDINGS     FEET        (D)         (D)      COSTS(D)     COST(E)
---------------------   ---------   -----------------  ---------   ---------  ----------   --------   ---------   ---------
<S>                     <C>         <C>                <C>         <C>        <C>          <C>        <C>         <C>
                         4Q/2001
San Rafael Corporate         and
  Center..............   3Q/2003    San Rafael, CA         5         388,000      80%      $ 30,720   $113,200    $141,500
Foundry Square (fka
  First and             2Q/2002 -
  Howard)(f)..........   3Q/2003    San Francisco, CA      4       1,260,000     (f)         37,099    249,000     436,200
Ferry Building(g).....   3Q/2002    San Francisco, CA      1         242,000      80%        11,117     66,000      82,400
Concar(h).............   4Q/2002    San Mateo, CA          2         207,000      80%         5,270     52,100      65,100
                                                          --       ---------               --------   --------    --------
                                                          12       2,097,000                 84,206    480,300     725,200
                                                          --       ---------               --------   --------    --------
Grand Total/Weighted Average                              15       2,617,000               $165,285   $648,100    $893,000
                                                          ==       =========               ========   ========    ========

<CAPTION>

                         CURRENT
WILSON/ EQUITY OFFICE   PERCENTAGE
   DEVELOPMENTS(C)        LEASED
---------------------   ----------
<S>                     <C>
San Rafael Corporate
  Center..............       0%
Foundry Square (fka
  First and
  Howard)(f)..........      42%
Ferry Building(g).....       0%
Concar(h).............      99%
                           ---
                            35%
                           ---
Grand Total/Weighted A      47%
                           ===
</TABLE>

---------------
(a) The Estimated Placed in Service Date represents the date the certificate of
    occupancy has been or is currently anticipated to be obtained. Subsequent to
    obtaining the certificate of occupancy, the Property is expected to undergo
    a lease-up period. The Total Estimated Costs represent current estimates of
    total development costs, including amounts required to tenant the Property.
    These costs are estimates and are subject to change upon or prior to
    completion of the development.

(b) Parkside Towers is 96% leased to Inktomi, however, Inktomi has notified EOP
    Partnership that it does not intend to take occupancy of the building.
    Inktomi remains obligated for this lease and is currently marketing the
    property for sublease.

(c) EOP Partnership and Wilson Investors ("WI") entered into a joint venture
    agreement to form Wilson/Equity Office ("W/EO") for the purpose of
    developing, constructing, leasing and managing developments. W/EO is owned
    49.9% by EOP Partnership and 50.1% by WI. William Wilson III, a trustee of
    Equity Office, through his ownership of WI, owns approximately 22% of W/EO
    (and approximately 30% of any promote to which WI is entitled under the
    joint venture agreement). EOP Partnership will loan up to $25 million to WI
    for its required contribution to W/EO at a 15% return per annum. The current
    outstanding balance of this loan as of 3/31/01 is approximately $8.4
    million.

    EOP Partnership has created or anticipates creating joint ventures with
    W/EO, and in certain cases, unaffiliated third parties for the development
    properties included herein. The costs for these developments will be funded
    by EOP Partnership and W/EO in a 60%/40% ratio and in some cases by third
    parties as described within each developments' respective operating
    agreement. The Board of Trustees has also authorized Equity Office to
    negotiate and enter into an agreement with W/EO providing for the extension
    of first mortgage financing to the ownership entities of each of these
    developments at LIBOR plus 2.4642%, generally maturing 36 months after
    initial funding (or earlier at the option of Equity Office in the event
    alternative financing sources are available on terms reasonably acceptable
    to WI and any unrelated third-party investors). The aggregate amount of any
    such financing would generally be capped at 70% of budgeted construction
    costs. In accordance with the W/EO Operating Agreement, EOP Partnership is
    entitled to purchase the W/EO interest in each development subsequent to
    project stabilization.

(d) The Estimated Placed in Service Date represents the date the certificate of
    occupancy has been or is currently anticipated to be obtained. Effective
    Ownership Percentage represents EOP Partnership's direct interest in the
    development and its 49.9% interest in W/EO. EOP Partnership's Costs Incurred
    as of March 31, 2001 and Total Estimated Costs are based on EOP
    Partnership's Effective Ownership Percentage. The remaining ownership
    interest/costs are owned/funded by WI through its investment in W/EO and on
    certain developments with unaffiliated third parties.

(e) Total Project Estimated Costs represent 100% of the estimated costs
    including EOP Partnership's, WI's and any unaffiliated third party's
    portions. These costs are subject to change upon or prior to the completion
    of the development and include amounts required to tenant the Property.

                                        26
<PAGE>   27

(f) Foundry Square is a project with four sites, each of which has a separate
    joint venture structure. EOP Partnership's Effective Ownership Percentages
    are approximately 64%, 68%, 40% and 40%, for Sites I through IV,
    respectively.

(g) Under the terms of the lease for the property, the lessor is entitled to
    share, in addition to base rent, in 50% of proceeds from the operation and
    ownership of this development after a preferred 11% cumulative return to the
    lessee (8% prior to project stabilization). Other partners may share in
    excess cash flow, if any.

(h) Under the terms of the ground lease, the ground lessor is entitled to share,
    in addition to ground rent, in proceeds from the operation and ownership of
    this development after a 10% return to the lessee, calculated at 25.7% of
    proceeds prior to a 14% cumulative return (18% after 2018) and 20.7%
    thereafter.

     In addition to the developments described above, EOP Partnership owns
various land parcels available for development. These sites represent possible
future development of up to approximately seven million square feet of office
space. The development of these sites will be impacted by the timing and
likelihood of success of the entitlement process, which is uncertain. These
various sites include, among others: Reston Town Center, Reston, VA; Prominence
in Buckhead, Atlanta, GA; Perimeter Center, Atlanta, GA; Tabor Center, Denver,
CO; Orange Center, Orange, CA; and City Center Bellevue, Bellevue, WA.

IMPACT OF NEW ACCOUNTING STANDARDS

     In June 1998, the FASB issued Statement No. 133 "Accounting for Derivative
Instruments and Hedging Activities." The statement requires recording all
derivative instruments as assets or liabilities, measured at fair value.
Derivatives that are not hedges must be adjusted to fair value through income.
If the derivative is a hedge, depending on the nature of the hedge, changes in
the fair value of derivatives will either be offset against the hedge in fair
value of the hedged assets, liabilities, or firm commitments through earnings or
recognized in other comprehensive income until the hedged item is recognized in
earnings. The ineffective portion of a derivative's change in fair value will be
immediately recognized in earnings. The standard's effective date was deferred
by FASB Statement No. 137 to all fiscal years beginning after June 15, 2000.
Equity Office adopted the standard on January 1, 2001, and recorded a cumulative
effect of a change in accounting principle resulting in a loss of approximately
$1.1 million in connection with Equity Office's share of the cumulative effect
of a change in accounting principle recorded on an interest rate cap in place at
a property held through a joint venture.

INFLATION

     Substantially all of the office leases require the tenant to pay, as
additional rent, a portion of any increases in real estate taxes (except, in the
case of certain California leases, which limit the ability of the landlord to
pass through to the tenants the effect of increased real estate taxes
attributable to a sale of real property interests) and operating expenses over a
base amount. In addition, many of the office leases provide for fixed increases
in base rent or indexed escalations (based on the Consumer Price Index or other
measures). EOP Partnership believes that the majority of inflationary increases
in expenses will be offset, in part, by the expense reimbursements and
contractual rent increases described above.

FUNDS FROM OPERATIONS

     Management of EOP Partnership believes Funds from Operations, as defined by
the Board of Governors of the National Association of Real Estate Investment
Trusts ("NAREIT") to be an appropriate measure of performance for an equity
REIT. While Funds from Operations is a relevant and widely used measure of
operating performance of equity REITs, it does not represent cash flow from
operations or net income as defined by GAAP, and it should not be considered as
an alternative to these indicators in evaluating liquidity or operating
performance of EOP Partnership.

                                        27
<PAGE>   28

     The following table reflects the calculation of Funds from Operations for
the three months ended March 31, 2001 and 2000, respectively:

<TABLE>
<CAPTION>
                                                                       FOR THE
                                                                 THREE MONTHS ENDED
                                                                      MARCH 31,
                                                                ---------------------
                   (DOLLARS IN THOUSANDS)                         2001         2000
------------------------------------------------------------    ---------    --------
<S>                                                             <C>          <C>
Income before allocation to minority interests, income from
  Investment in unconsolidated joint ventures, net gain on
  sales of real estate, extraordinary items and cumulative
  effect of a change in accounting principle................    $ 136,991    $101,679
Add (deduct):
  Income allocated to minority interests for partially owned
     properties.............................................       (3,253)       (553)
  Income from investment in unconsolidated joint ventures...       15,426      11,374
  Depreciation and amortization (real estate related)
     (including EOP Partnership's share of unconsolidated
     joint ventures)........................................      134,311      94,786
  Put option settlement.....................................           --      (1,030)
  Preferred distributions...................................      (10,884)    (10,697)
                                                                ---------    --------
Funds from Operations(1)....................................      272,591     195,559
  Less deferred rental revenue..............................      (14,985)    (12,707)
  Plus deferred rental expense..............................          661         501
                                                                ---------    --------
Adjusted Funds from Operations..............................    $ 258,267    $183,353
                                                                =========    ========
Cash Flow Provided By (Used For):
  Operating Activities......................................    $ 192,801    $109,489
  Investing Activities......................................    $ (63,672)   $(65,929)
  Financing Activities......................................    $(144,775)   $(29,522)
Ratio of earnings to combined fixed charges and preferred
  share distributions.......................................          1.8         1.8
</TABLE>

---------------
(1) The White Paper on Funds from Operations approved by NAREIT in March 1995
    defines Funds from Operations as net income (loss), computed in accordance
    with GAAP, excluding gains (or losses) from debt restructuring and sales of
    properties, plus real estate related depreciation and amortization and after
    adjustments for unconsolidated partnerships and joint ventures. In November
    1999, NAREIT issued a National Policy Bulletin effective January 1, 2000
    clarifying the definition of Funds from Operations to include all operating
    results, both recurring and non-recurring, except those defined as
    extraordinary under GAAP. EOP Partnership believes that Funds from
    Operations is helpful to investors as a measure of the performance of an
    equity REIT because, along with cash flow from operating activities,
    financing activities and investing activities, it provides investors with an
    indication of the ability of EOP Partnership to incur and service debt, to
    make capital expenditures and to fund other cash needs. EOP Partnership
    computes Funds from Operations in accordance with standards established by
    NAREIT, which may not be comparable to Funds from Operations reported by
    other REITs that do not define the term in accordance with the current
    NAREIT definition or that interpret the current NAREIT definition
    differently than EOP Partnership. Funds from Operations does not represent
    cash generated from operating activities in accordance with GAAP, nor does
    it represent cash available to pay distributions and should not be
    considered as an alternative to net income, determined in accordance with
    GAAP, as an indication of EOP Partnership's financial performance or to cash
    flow from operating activities, determined in accordance with GAAP, as a
    measure of EOP Partnership's liquidity, nor is it indicative of funds
    available to fund EOP Partnership's cash needs, including its ability to
    make cash distributions.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

     Since December 31, 2000, there have been no material changes in the
information regarding market risk that was provided in EOP Partnership's Form
10-K for the year ended December 31, 2000.

                                        28
<PAGE>   29

                           PART II. OTHER INFORMATION

ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K.

     (a) Exhibits

<TABLE>
<CAPTION>
        EXHIBIT
          NO.                                          DESCRIPTION
        -------                                        -----------
<C>                            <S>
           2.3                 Agreement and Plan of Merger, dated February 23, 2001, among
                               Equity Office, EOP Partnership, Spieker Properties, Inc. and
                               Spieker, L.P. (incorporated herein by reference to Exhibit
                               2.1 to Equity Office's Current Report on Form 8-K filed with
                               the SEC on March 9, 2001), including Exhibits D-I and K
                               thereto. The registrant agrees to furnish supplementally a
                               copy of Exhibits A-C and J to the SEC upon request.
          10.1                 Bridge Facility Commitment Letter
          10.2                 Fee Letter for Bridge Loan Facility dated May 11, 2001
          12.1                 Statement of computation of earnings to combined fixed
                               charges and preferred share distributions.
</TABLE>

     (b) Reports on Form 8-K

     On February 28, 2001, EOP Partnership filed a Current Report on Form 8-K,
Item 9, dated February 27, 2001, containing information included in a
presentation made on behalf of Equity Office by Richard Kincaid, Executive Vice
President and Chief Financial Officer of Equity Office.

     On March 9, 2001, EOP Partnership filed a Current Report on Form 8-K, Item
5 dated February 22, 2001, in connection with the announced merger agreement
with Spieker Properties, Inc.

                                        29
<PAGE>   30

                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                        EOP OPERATING LIMITED PARTNERSHIP

                                        By: EQUITY OFFICE PROPERTIES TRUST
                                           its general partner

Date: May 15, 2001                      By:      /s/ STANLEY M. STEVENS
                                           -------------------------------------
                                                    Stanley M. Stevens
                                                 Executive Vice President,
                                             Chief Legal Counsel and Secretary

Date: May 15, 2001                      By:      /s/ RICHARD D. KINCAID
                                           -------------------------------------
                                                    Richard D. Kincaid
                                                 Executive Vice President,
                                                  Chief Financial Officer

                                        30
<PAGE>   31

                               INDEX TO EXHIBITS

<TABLE>
<CAPTION>
        EXHIBIT
          NO.                                          DESCRIPTION
        -------                                        -----------
<C>                            <S>
           2.3                 Agreement and Plan of Merger, dated February 23, 2001, among
                               Equity Office, EOP Partnership, Spieker Properties, Inc. and
                               Spieker, L.P. (incorporated herein by reference to Exhibit
                               2.1 to Equity Office's Current Report on Form 8-K filed with
                               the SEC on March 9, 2001), including Exhibits D-I and K
                               thereto. The registrant agrees to furnish supplementally a
                               copy of Exhibits A-C and J to the SEC upon request.
          10.1                 Bridge Facility Commitment Letter
          10.2                 Fee Letter for Bridge Loan Facility dated May 11, 2001
          12.1                 Statement of computation of earnings to combined fixed
                               charges and preferred share distributions.
</TABLE>

                                        31