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

FORM 10-K

MACK-CALI REALTY CORPORATION
(Exact Name of Registrant as specified in its charter)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:
None

        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 ý    No o

        Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of the registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendments to this Form 10-K. ý

        Indicate by check mark whether the registrant is an accelerated filer (as defined in Exchange Act Rule 12b-2). Yes ý    No o

        As of February 20, 2004, the aggregate market value of the voting stock held by non-affiliates of the registrant was $2,495,113,846. The aggregate market value was computed with references to the closing price on the New York Stock Exchange on such date. This calculation does not reflect a determination that persons are affiliates for any other purpose.

        As of February 20, 2004, 60,084,282 shares of common stock, $0.01 par value, of the Company ("Common Stock") were outstanding.

        LOCATION OF EXHIBIT INDEX: The index of exhibits is contained herein on page number 135.

        DOCUMENTS INCORPORATED BY REFERENCE: Portions of the registrant's definitive proxy statement for fiscal year ended December 31, 2003 to be issued in conjunction with the registrant's annual meeting of shareholders expected to be held on May 20, 2004 are incorporated by reference in Part III of this Form 10-K. The definitive proxy statement will be filed by the registrant with the SEC not later than 120 days from the end of the Registrant's fiscal year ended December 31, 2003.

TABLE OF CONTENTS
FORM 10-K

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PART I

ITEM 1.    BUSINESS

GENERAL

        Mack-Cali Realty Corporation, a Maryland corporation (together with its subsidiaries, the "Company"), is a fully-integrated, self-administered and self-managed real estate investment trust ("REIT") that owns and operates a real estate portfolio comprised predominantly of Class A office and office/flex properties located primarily in the Northeast. The Company performs substantially all commercial real estate leasing, management, acquisition, development and construction services on an in-house basis. Mack-Cali Realty Corporation was incorporated on May 24, 1994. The Company's executive offices are located at 11 Commerce Drive, Cranford, New Jersey 07016, and its telephone number is (908) 272-8000. The Company has an internet website at www.mack-cali.com.

        As of December 31, 2003, the Company owned or had interests in 263 properties, aggregating approximately 28.3 million square feet (collectively, the "Properties"), plus developable land. The Properties are comprised of: (a) 256 wholly-owned or Company-controlled properties consisting of 150 office buildings and 96 office/flex buildings aggregating approximately 26.6 million square feet, six industrial/warehouse buildings totaling approximately 387,400 square feet, two stand-alone retail properties totaling approximately 17,300 square feet, and two land leases (collectively, the "Consolidated Properties"); and (b) four office buildings and one office/flex building aggregating 1.2 million square feet, a 100,740 square-foot mixed use retail property and a 350-room hotel, which are owned by unconsolidated joint ventures in which the Company has investment interests. Unless otherwise indicated, all references to square feet represent net rentable area. As of December 31, 2003, the office, office/flex, industrial/warehouse and stand-alone retail properties included in the Consolidated Properties were 91.5 percent leased to approximately 2,100 tenants. Percentage leased includes all leases in effect as of the period end date, some of which have commencement dates in the future and leases that expire at the period end date. Leases that expire as of the period end date aggregate 143,059 square feet, or 0.5 percent of the net rentable square footage. The Properties are located in eight states, primarily in the Northeast, and the District of Columbia. See Item 2: Properties.

        The Company's strategy has been to focus its operations, acquisition and development of office properties in high-barrier-to-entry markets and sub-markets where it believes it is, or can become, a significant and preferred owner and operator. The Company will continue this strategy by expanding through acquisitions and/or development in Northeast markets where it has, or can achieve, similar status. The Company believes that its Properties have excellent locations and access and are well-maintained and professionally managed. As a result, the Company believes that its Properties attract high quality tenants and achieve among the highest rental, occupancy and tenant retention rates within their markets. The Company also believes that its extensive market knowledge provides it with a significant competitive advantage, which is further enhanced by its strong reputation for, and emphasis on, delivering highly responsive, professional management services. See "Business Strategies".

        As of December 31, 2003, executive officers and directors of the Company and their affiliates owned approximately 9.8 percent of the Company's outstanding shares of Common Stock (including Units redeemable or convertible into shares of Common Stock). As used herein, the term "Units" refers to limited partnership interests in Mack-Cali Realty, L.P., a Delaware limited partnership ("Operating Partnership"), through which the Company conducts its real estate activities. The Company's executive officers have been employed by the Company and/or its predecessor companies for an average of approximately 16 years.

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BUSINESS STRATEGIES

Operations

        Reputation:    The Company has established a reputation as a highly-regarded landlord with an emphasis on delivering quality tenant services in buildings it owns and/or manages. The Company believes that its continued success depends in part on enhancing its reputation as an operator of choice, which will facilitate the retention of current tenants and the attraction of new tenants. The Company believes it provides a superior level of service to its tenants, which should in turn allow the Company to outperform the market with respect to occupancy rates, as well as improve tenant retention.

        Communication with tenants:    The Company emphasizes frequent communication with tenants to ensure first-class service to the Properties. Property managers generally are located on site at the Properties to provide convenient access to management and to ensure that the Properties are well-maintained. Property management's primary responsibility is to ensure that buildings are operated at peak efficiency in order to meet both the Company's and tenants' needs and expectations. Property managers additionally budget and oversee capital improvements and building system upgrades to enhance the Properties' competitive advantages in their markets and to maintain the quality of the Company's properties.

        Additionally, the Company's in-house leasing representatives develop and maintain long-term relationships with the Company's diverse tenant base and coordinate leasing, expansion, relocation and build-to-suit opportunities within the Company's portfolio. This approach allows the Company to offer office space in the appropriate size and location to current or prospective tenants in any of its sub-markets.

Growth

        The Company plans to continue to own and operate a portfolio of properties in high-barrier-to-entry markets, with a primary focus in the Northeast. The Company's primary objectives are to maximize operating cash flow and to enhance the value of its portfolio through effective management, acquisition, development and property sales strategies, as follows:

        Internal Growth:    The Company seeks to maximize the value of its existing portfolio through implementing operating strategies designed to produce the highest effective rental and occupancy rates and lowest tenant installation cost within the markets that it operates. The Company continues to pursue internal growth through re-leasing space at higher effective rents with contractual rent increases and developing or redeveloping space for its diverse base of high credit tenants, including Citigroup, Dow Jones, Merck and Prudential Insurance. In addition, the Company seeks economies of scale through volume discounts to take advantage of its size and dominance in particular sub-markets, and operating efficiencies through the use of in-house management, leasing, marketing, financing, accounting, legal, development and construction services.

        Acquisitions:    The Company also believes that growth opportunities exist through acquiring operating properties or properties for redevelopment with attractive returns in its core Northeast sub-markets where, based on its expertise in leasing, managing and operating properties, it believes it is, or can become, a significant and preferred owner and operator. The Company intends to acquire, invest in or redevelop additional properties that: (i) are expected to provide attractive initial yields with potential for growth in cash flow from operations; (ii) are well-located, of high quality and competitive in their respective sub-markets; (iii) are located in its existing sub-markets or in sub-markets in which the Company can become a significant and preferred owner and operator; and (iv) it believes have been under-managed or are otherwise capable of improved performance through intensive management, capital improvements and/or leasing that should result in increased effective rental and occupancy rates.

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        Development:    The Company seeks to selectively develop additional properties where it believes such development will result in a favorable risk-adjusted return on investment in coordination with the above operating strategies. Such development primarily will occur: (i) when leases have been executed prior to construction; (ii) in stable core Northeast sub-markets where the demand for such space exceeds available supply; and (iii) where the Company is, or can become, a significant and preferred owner and operator.

        Property Sales:    While management's principal intention is to own and operate its properties on a long-term basis, it periodically assesses the attributes of each of its properties, with a particular focus on the supply and demand fundamentals of the sub-markets in which they are located. Based on these ongoing assessments, the Company may, from time to time, decide to sell any of its properties.

Financial

        The Company currently intends to maintain a ratio of debt-to-undepreciated assets (total debt of the Company as a percentage of total undepreciated assets) of 50 percent or less. As of December 31, 2003, the Company's total debt constituted approximately 37.9 percent of total undepreciated assets of the Company. The Company has three investment grade credit ratings. Standard & Poor's Rating Services ("S&P") and Fitch, Inc. ("Fitch") have each assigned their BBB rating to existing and prospective senior unsecured debt of the Operating Partnership. S&P and Fitch have also assigned their BBB- rating to existing and prospective preferred stock offerings of the Company. Moody's Investors Service ("Moody's") has assigned its Baa2 rating to existing and prospective senior unsecured debt of the Operating Partnership and its Baa3 rating to existing and prospective preferred stock offerings of the Company. Although there is no limit in the Company's organizational documents on the amount of indebtedness that the Company may incur or a requirement for the maintenance of investment grade credit ratings, the Company has entered into certain financial agreements which contain covenants that limit the Company's ability to incur indebtedness under certain circumstances. The Company intends to conduct its operations so as to best be able to maintain its investment grade rated status. The Company intends to utilize the most appropriate sources of capital for future acquisitions, development, capital improvements and other investments, which may include funds from operating activities, proceeds from property and land sales, short-term and long-term borrowings (including draws on the Company's revolving credit facility), and the issuance of additional debt or equity securities.

EMPLOYEES

        As of December 31, 2003, the Company had approximately 335 full-time employees.

COMPETITION

        The leasing of real estate is highly competitive. The Properties compete for tenants with lessors and developers of similar properties located in their respective markets primarily on the basis of location, rent charged, services provided, and the design and condition of the Properties. The Company also experiences competition when attempting to acquire or dispose of real estate, including competition from domestic and foreign financial institutions, other REITs, life insurance companies, pension trusts, trust funds, partnerships, individual investors and others.

REGULATIONS

        Many laws and governmental regulations are applicable to the Properties and changes in these laws and regulations, or their interpretation by agencies and the courts, occur frequently.

        Under various laws and regulations relating to the protection of the environment, an owner of real estate may be held liable for the costs of removal or remediation of certain hazardous or toxic substances located on or in the property. These laws often impose liability without regard to whether

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the owner was responsible for, or even knew of, the presence of such substances. The presence of such substances may adversely affect the owner's ability to rent or sell the property or to borrow using such property as collateral and may expose it to liability resulting from any release of, or exposure to, such substances. Persons who arrange for the disposal or treatment of hazardous or toxic substances at another location may also be liable for the costs of removal or remediation of such substances at the disposal or treatment facility, whether or not such facility is owned or operated by such person. Certain environmental laws impose liability for the release of asbestos-containing materials into the air, and third parties may also seek recovery from owners or operators of real properties for personal injury associated with asbestos-containing materials and other hazardous or toxic substances.

        In connection with the ownership (direct or indirect), operation, management and development of real properties, the Company may be considered an owner or operator of such properties or as having arranged for the disposal or treatment of hazardous or toxic substances and, therefore, potentially liable for removal or remediation costs, as well as certain other related costs, including governmental penalties and injuries to persons and property.

        There can be no assurance that (i) future laws, ordinances or regulations will not impose any material environmental liability, (ii) the current environmental condition of the Properties will not be affected by tenants, by the condition of land or operations in the vicinity of the Properties (such as the presence of underground storage tanks), or by third parties unrelated to the Company, or (iii) the Company's assessments reveal all environmental liabilities and that there are no material environmental liabilities of which the Company is aware. If compliance with the various laws and regulations, now existing or hereafter adopted, exceeds the Company's budgets for such items, the Company's ability to make expected distributions to stockholders could be adversely affected.

        There are no other laws or regulations which have a material effect on the Company's operations, other than typical federal, state and local laws affecting the development and operation of real property, such as zoning laws.

INDUSTRY SEGMENTS

        The Company operates in only one industry segment—real estate. The Company does not have any foreign operations and its business is not seasonal. Please see our financial statements attached hereto and incorporated by reference herein for financial information relating to our industry segment.

RECENT DEVELOPMENTS

        As a result of the economic climate since 2001, substantially all of the real estate markets the Company operates in materially softened. Demand for office space declined significantly and vacancy rates increased in each of the Company's core markets over the period. Through February 20, 2004, the Company's core markets continued to be weak. The percentage leased in the Company's consolidated portfolio of stabilized operating properties decreased to 91.5 percent at December 31, 2003, as compared to 92.3 percent at December 31, 2002 and 94.6 percent at December 31, 2001. Percentage leased includes all leases in effect as of the period end date, some of which have commencement dates in the future and leases that expire at the period end date. Market rental rates have declined in most markets from peak levels in late 2000 and early 2001. Rental rates on the Company's space that was re-leased (based on first rents payable) during the year ended December 31, 2003 decreased an average of 7.8 percent compared to rates that were in effect under expiring leases, as compared to a 3.0 percent increase in 2002 and a 9.5 percent increase in 2001. The Company believes that vacancy rates may continue to increase in most of its markets in 2004.

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        In 2003, the Company:

•

acquired two office and one office/flex properties, aggregating 202,184 square feet, at a total cost of approximately $24.9 million and;



•

sold two office properties, aggregating 351,842 square feet, and a land parcel for aggregate net sales proceeds of approximately $18.7 million.

        Additionally, in 2003, the Company, through unconsolidated joint ventures, sold two office properties, aggregating 850,769 square feet, for aggregate net sales proceeds of approximately $214.6 million. See Note 4 to the Financial Statements for further information regarding joint venture activity.

Property Acquisitions

        The Company acquired the following operating properties during the year ended December 31, 2003:

(a)

Transactions were funded primarily through borrowings on the Company's revolving credit facility, from net proceeds received in the sale or sales of rental property, and/or from the Company's cash reserves. Amounts are as of December 31, 2003.

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Sales

        The Company sold the following properties during the year ended December 31, 2003:

        On September 29, 2003, the Company sold its interest in American Financial Exchange L.L.C. ("AFE"), in which the Company held a 50 percent interest, and received approximately $162.1 million in net sales proceeds from the transaction, which the Company used primarily to repay outstanding borrowings under its unsecured revolving credit facility. The Company recognized a gain on the sale of approximately $24.0 million, which is recorded in gain on sale of investment in unconsolidated joint venture for the year ended December 31, 2003.

        In advance of the transaction, AFE distributed its interests in Plaza VIII and IX Associates, L.L.C., which owned the undeveloped land currently used as a parking facility, to its then partners, the Company and Columbia Development Company, L.L.C. ("Columbia"). The Company and Columbia subsequently entered into a new joint venture agreement to own and manage the undeveloped land and related parking operations through Plaza VIII and IX Associates, L.L.C. The Company and Columbia each hold a 50 percent interest in the new venture.

Development

        On November 25, 2003, the Company and affiliates of The Mills Corporation ("Mills") entered into a joint venture agreement to form Meadowlands Mills/Mack-Cali Limited Partnership ("Meadowlands Venture") for the purpose of developing a $1.3 billion family entertainment and recreation complex with an office and hotel component to be built at the Meadowlands sports complex in East Rutherford, New Jersey ("Meadowlands Xanadu"). Meadowlands Xanadu's approximately 4.76 million-square-foot complex is expected to feature a family entertainment destination comprising three themed zones: sports/recreation, children's activities and fashion, in addition to four office buildings, aggregating approximately 1.8 million square feet, and a 520-room hotel.

        On December 3, 2003, the Meadowlands Venture entered into a redevelopment agreement with the New Jersey Sports and Exposition Authority ("NJSEA") (the "Redevelopment Agreement") for the redevelopment of the area surrounding the Continental Airlines Arena in East Rutherford, New Jersey and the construction of the Meadowlands Xanadu project. The Redevelopment Agreement provides for a 75-year ground lease, which requires the joint venture to pay the NJSEA a $160 million development rights fee at the start of construction of the entertainment phase, when all permits and approvals are obtained, and the payment of fixed rent over the term. Fixed rent will be in the amount of $1,000 per year for the first 15 years, increasing to $7.5 million from the 16th to the 22nd year, then to $9.2 million in the 23rd year, with additional increases over the remainder of the term, as set forth in

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the ground lease. The ground lease also allows for the potential for participation rent payments by the venture, as described in the ground lease agreement.

        The Company and Mills own a 20 percent and 80 percent interest, respectively, in the Meadowlands Venture, subject to certain participation rights by The New York Giants. The joint venture agreement requires the Company to make an equity contribution up to a maximum of $32.5 million. As part of the Redevelopment Agreement, Mills is required to contribute certain vacant land, known as the Empire Tract, to the State of New Jersey to be used as a wetlands mitigation bank, for which Mills has received subordinated capital credit in the venture of approximately $118 million. The joint venture agreement requires Mills to contribute the balance of the capital required to complete the entertainment phase, subject to certain limitations. The Company will receive a nine percent preferred return on its equity investment, only after Mills receives a nine percent preferred return on its equity investment. Residual returns, subject to participation by other parties, will be in proportion to each partners' respective percentage interest.

        Mills will develop, lease and operate the entertainment phase of the Meadowlands Xanadu project. The joint venture agreement provides the Company an option to cause the Meadowlands Venture to form component ventures for the future development of the office and hotel phases, for which the Company will develop, lease and operate such phases. The Company will own an 80 percent interest and Mills will own a 20 percent interest in such entities. The agreement provides for the first office or hotel component ventures to be formed no later than four years after the grand opening of the entertainment phase, and requires that all component ventures for the office and hotel phases be formed no later than 10 years from such date, but does not require that any or all components be developed. However, under the Meadowlands Venture agreement, Mills has the ability to accelerate such formation schedule, subject to certain conditions. Should the Company fail to meet the time schedule described above for the formation of the component ventures, the Company will forfeit its rights to cause the Meadowlands Venture to form additional component ventures. If this occurs, Mills will have the ability to develop the additional phases, subject to the Company's right to participate, or to cause the Meadowlands Venture to sell such components to a third party, subject to a sales price limitation of 95 percent of the value that would have been the amount necessary to form such component ventures.

FINANCING ACTIVITY

Senior Unsecured Notes Transactions

        On March 14, 2003, the Company exchanged $25 million face amount of existing 7.18 percent senior unsecured notes due December 31, 2003, with interest payable monthly in arrears, for $26.1 million face amount of 5.82 percent senior unsecured notes due March 15, 2013, with interest payable semi-annually in arrears. The exchange was completed with Teachers Insurance and Annuity Association ("TIAA"). In addition, the Company used the net proceeds from the issuance of preferred stock, together with available cash, to repurchase $25 million face amount of notes due December 31, 2003 from TIAA for $26.1 million. See Issuance of Preferred Stock below. The Company recorded $1.4 million in loss on early retirement of debt, net, for the year ended December 31, 2003 for costs incurred in connection with the notes transactions.

        On June 12, 2003, the Company issued $100 million face amount of 4.60 percent senior unsecured notes due June 15, 2013, with interest payable semi-annually in arrears. The total proceeds from the issuance (net of selling commissions and discount) of approximately $99.1 million was used primarily to repay $62.8 million of mortgage debt at a discount of $1.7 million (recorded as a reduction in loss on early retirement of debt, net in 2003), and to repay outstanding borrowings under the Company's unsecured revolving credit facility. The Company recorded $1.5 million in loss on early retirement of debt, net, in the year ended December 31, 2003 for the write-off of the unamortized balance of an

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interest rate contract in conjunction with the repayment of mortgage debt. The unsecured notes were issued at a discount of approximately $286,000, which is being amortized over the term as an adjustment to interest expense.

        On June 25, 2003, the Company repurchased $45.3 million face amount of existing 7.18 percent senior unsecured notes due December 31, 2003, with interest payable monthly in arrears, for $46.7 million from TIAA. The repurchase fully retired the 7.18 percent senior unsecured notes which were due December 31, 2003. The Company recorded $1.4 million in loss on early retirement of debt, net, for the year ended December 31, 2003 for costs incurred in connection with the notes repurchase.

        On February 9, 2004, the Company issued $100 million face amount of 5.125 percent senior unsecured notes due February 15, 2014, with interest payable semi-annually in arrears. The total proceeds from the issuance (net of selling commissions and discount) of approximately $98.5 million will be held until March 15, 2004, at which time the Company intends to use the net proceeds from the sale, together with borrowings under its unsecured revolving credit facility and available cash, to repay the $300 million, 7.00 percent notes due on that date.

Issuance of Preferred Stock

        On March 14, 2003, in a publicly registered transaction with a single institutional buyer, the Company completed the sale and issuance of 10,000 shares of eight-percent Series C cumulative redeemable perpetual preferred stock ("Series C Preferred Stock") in the form of 1,000,000 depositary shares ($25 stated value per depositary share). Each depositary share represents 1/100th of a share of Series C Preferred Stock. The Company received net proceeds of approximately $24.8 million from the sale. The Company used the net proceeds, together with available cash, to repurchase $25 million face amount of notes due December 31, 2003 from TIAA for $26.1 million. See Senior Unsecured Notes Transactions above.

RISK FACTORS

        Our results from operations and ability to make distributions on our equity and debt service on our indebtedness may be affected by the risk factors set forth below. All investors should consider the following risk factors before deciding to purchase securities of the Company. The Company refers to itself as "we" or "our" in the following risk factors.

Declines in economic activities in the Northeastern office markets could adversely affect our operating results.

        A majority of our revenues are derived from our properties located in the Northeast, particularly in New Jersey, New York, Pennsylvania and Connecticut. Adverse economic developments in this region could adversely impact the operations of our properties and, therefore, our profitability. Because our portfolio consists primarily of office and office/flex buildings (as compared to a more diversified real estate portfolio), a decline in the economy and/or a decline in the demand for office space may adversely affect our ability to make distributions or payments to our investors.

        The continued economic downturn in the real estate market has resulted in the relocation of companies and an uncertain economic future for many businesses. We are uncertain how long the current downturn will last. The current economic downturn may also be having a negative economic impact on many industries, including securities, insurance services, telecommunications and computer systems and other technology, businesses in which many of our tenants are involved. Such economic impact may cause our tenants to have difficulty or be unable to meet their obligations to us.

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Our performance is subject to risks associated with the real estate industry.

        General:    Our ability to make distributions or payments to our investors depends on the ability of our properties to generate funds in excess of operating expenses (including scheduled principal payments on debt and capital expenditure requirements). Events or conditions that are beyond our control may adversely affect our operations and the value of our properties. Such events or conditions could include:

•

changes in the general economic climate;



•

changes in local conditions such as an oversupply of office space, a reduction in demand for office space, or reductions in office market rental rates;



•

decreased attractiveness of our properties to tenants;



•

competition from other office and office/flex properties;



•

our inability to provide adequate maintenance;



•

increased operating costs, including insurance premiums, utilities and real estate taxes, due to inflation and other factors which may not necessarily be offset by increased rents;



•

changes in laws and regulations (including tax, environmental, zoning and building codes, and housing laws and regulations) and agency or court interpretations of such laws and regulations and the related costs of compliance;



•

changes in interest rate levels and the availability of financing;



•

the inability of a significant number of tenants to pay rent;



•

our inability to rent office space on favorable terms; and



•

civil unrest, earthquakes and other natural disasters or acts of God that may result in uninsured losses.

        Financially distressed tenants may be unable to pay rent:    If a tenant defaults, we may experience delays and incur substantial costs in enforcing our rights as landlord and protecting our investments. If a tenant files for bankruptcy, a potential court judgment rejecting and terminating such tenant's lease could adversely affect our ability to make distributions or payments to our investors.

        Renewing leases or re-letting space could be costly:    If a tenant does not renew its lease upon expiration or terminates its lease early, we may not be able to re-lease the space. If a tenant does renew its lease or we re-lease the space, the terms of the renewal or new lease, including the cost of required renovations or concessions to the tenant, may be less favorable than the current lease terms which could adversely affect our ability to make distributions or payments to our investors.

        Our insurance coverage on our properties may be inadequate:    We currently carry comprehensive insurance on all of our properties, including insurance for liability, fire and flood. We cannot guarantee that the limits of our current policies will be sufficient in the event of a catastrophe to our properties. We cannot guarantee that we will be able to renew or duplicate our current insurance coverage in adequate amounts or at reasonable prices. In addition, while our current insurance policies insure us against loss from terrorist acts and toxic mold, in the future insurance companies may no longer offer coverage against these types of losses, or, if offered, these types of insurance may be prohibitively expensive. If any or all of the foregoing should occur, we may not have insurance coverage against certain types of losses and/or there may be decreases in the limits of insurance available. Should an uninsured loss or a loss in excess of our insured limits occur, we could lose all or a portion of the capital we have invested in a property or properties, as well as the anticipated future revenue from the property or properties. Nevertheless, we might remain obligated for any mortgage debt or other

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financial obligations related to the property or properties. We cannot guarantee that material losses in excess of insurance proceeds will not occur in the future. If any of our properties were to experience a catastrophic loss, it could seriously disrupt our operations, delay revenue and result in large expenses to repair or rebuild the property. Such events could adversely affect our ability to make distributions or payments to our investors.

        Illiquidity of real estate limits our ability to act quickly:    Real estate investments are relatively illiquid. Such illiquidity may limit our ability to react quickly in response to changes in economic and other conditions. If we want to sell an investment, we might not be able to dispose of that investment in the time period we desire, and the sales price of that investment might not recoup or exceed the amount of our investment. The prohibition in the Internal Revenue Code of 1986, as amended, and related regulations on a real estate investment trust holding property for sale also may restrict our ability to sell property. In addition, we acquired a significant number of our properties from individuals to whom we issued limited partnership units as part of the purchase price. In connection with the acquisition of these properties, in order to preserve such individual's tax deferral, we contractually agreed not to sell or otherwise transfer the properties for a specified period of time, except in a manner which does not result in recognition of any built-in-gain (which may result in an income tax liability) or which reimburses the appropriate individuals for the tax consequences of the recognition of such built-in-gains. As of December 31, 2003, 140 of our properties, with an aggregate net book value of approximately $1.8 billion, were subject to these restrictions, which expire periodically through 2008. The above limitations on our ability to sell our investments could adversely affect our ability to make distributions or payments to our investors.

        Americans with Disabilities Act compliance could be costly:    Under the Americans with Disabilities Act of 1990 ("ADA"), all public accommodations and commercial facilities must meet certain federal requirements related to access and use by disabled persons. Compliance with the ADA requirements could involve removal of structural barriers from certain disabled persons' entrances. Other federal, state and local laws may require modifications to or restrict further renovations of our properties with respect to such accesses. Although we believe that our properties are substantially in compliance with present requirements, noncompliance with the ADA or related laws or regulations could result in the United States government imposing fines or private litigants being awarded damages against us. Such costs may adversely affect our ability to make distributions or payments to our investors.

        Environmental problems are possible and may be costly:    Various federal, state and local laws and regulations subject property owners or operators to liability for the costs of removal or remediation of certain hazardous or toxic substances located on or in the property. These laws often impose liability without regard to whether the owner or operator was responsible for or even knew of the presence of such substances. The presence of or failure to properly remediate hazardous or toxic substances (such as toxic mold) may adversely affect our ability to rent, sell or borrow against contaminated property. Various laws and regulations also impose liability on persons who arrange for the disposal or treatment of hazardous or toxic substances at another location for the costs of removal or remediation of such substances at the disposal or treatment facility. These laws often impose liability whether or not the person arranging for such disposal ever owned or operated the disposal facility. Certain other environmental laws and regulations impose liability on owners or operators of property for injuries relating to the release of asbestos-containing materials into the air. As owners and operators of property and as potential arrangers for hazardous substance disposal, we may be liable under such laws and regulations for removal or remediation costs, governmental penalties, property damage, personal injuries and related expenses. Payment of such costs and expenses could adversely affect our ability to make distributions or payments to our investors.

        Competition for acquisitions may result in increased prices for properties:    We plan to acquire additional properties in New Jersey, New York and Pennsylvania and in the Northeast generally. We

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may be competing for investment opportunities with entities that have greater financial resources. Several office building developers and real estate companies may compete with us in seeking properties for acquisition, land for development and prospective tenants. Such competition may adversely affect our ability to make distributions or payments to our investors by:

•

reducing the number of suitable investment opportunities offered to us;



•

increasing the bargaining power of property owners;



•

interfering with our ability to attract and retain tenants;



•

increasing vacancies which lowers market rental rates and limits our ability to negotiate rental rates; and/or



•

adversely affecting our ability to minimize expenses of operation.

        Development of real estate could be costly:    As part of our operating strategy, we may acquire land for development or construct on owned land, under certain conditions. Included among the risks of the real estate development business are the following, which may adversely affect our ability to make distributions or payments to our investors:

•

financing for development projects may not be available on favorable terms;



•

long-term financing may not be available upon completion of construction; and



•

failure to complete construction on schedule or within budget may increase debt service expense and construction costs.

        Property ownership through joint ventures could subject us to the contrary business objectives of our co-venturers:    We, from time to time, invest in joint ventures or partnerships in which we do not hold a controlling interest. These investments involve risks that do not exist with properties in which we own a controlling interest, including the possibility that our co-venturers or partners may, at any time, have business, economic or other objectives that are inconsistent with our objectives. Because we lack a controlling interest, our co-venturers or partners may be in a position to take action contrary to our instructions or requests or contrary to our policies or objectives. While we seek protective rights against such contrary actions, there can be no assurance that we will be successful in procuring any such protective rights, or if procured, that the rights will be sufficient to fully protect us against contrary actions. Our organizational documents do not limit the amount of available funds that we may invest in joint ventures or partnerships. If the objectives of our co-venturers or partners are inconsistent with ours, it may adversely affect our ability to make distributions or payments to our investors.

Debt financing could adversely affect our economic performance.

        Scheduled debt payments and refinancing could adversely affect our financial condition:    We are subject to the risks normally associated with debt financing. These risks, including the following, may adversely affect our ability to make distributions or payments to our investors:

•

our cash flow may be insufficient to meet required payments of principal and interest;



•

payments of principal and interest on borrowings may leave us with insufficient cash resources to pay operating expenses;



•

we may not be able to refinance indebtedness on our properties at maturity; and



•

if refinanced, the terms of refinancing may not be as favorable as the original terms of the related indebtedness.

        As of December 31, 2003, we had total outstanding indebtedness of $1.6 billion comprised of $1.1 billion of senior unsecured notes and approximately $500.7 million of mortgage indebtedness. We

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may have to refinance the principal due on our current or future indebtedness at maturity, and we may not be able to do so.

        If we are unable to refinance our indebtedness on acceptable terms, or at all, events or conditions that may adversely affect our ability to make distributions or payments to our investors include the following:

•

we may need to dispose of one or more of our properties upon disadvantageous terms;



•

prevailing interest rates or other factors at the time of refinancing could increase interest rates and, therefore, our interest expense;



•

if we mortgage property to secure payment of indebtedness and are unable to meet mortgage payments, the mortgagee could foreclose upon such property or appoint a receiver to receive an assignment of our rents and leases; and



•

foreclosures upon mortgaged property could create taxable income without accompanying cash proceeds and, therefore, hinder our ability to meet the real estate investment trust distribution requirements of the Internal Revenue Code.

        We are obligated to comply with financial covenants in our indebtedness that could restrict our range of operating activities:    The mortgages on our properties contain customary negative covenants, including limitations on our ability, without the prior consent of the lender, to further mortgage the property, to enter into new leases outside of stipulated guidelines or to materially modify existing leases. In addition, our credit facility contains customary requirements, including restrictions and other limitations on our ability to incur debt, debt to assets ratios, secured debt to total assets ratios, debt service coverage ratios and minimum ratios of unencumbered assets to unsecured debt. The indentures under which our senior unsecured debt have been issued contain financial and operating covenants including coverage ratios and limitations on our ability to incur secured and unsecured debt. These covenants limit our flexibility in conducting our operations and create a risk of default on our indebtedness if we cannot continue to satisfy them.

        Rising interest rates may adversely affect our cash flow:    As of December 31, 2003, approximately $32.2 million of our mortgage indebtedness bears interest at variable rates. We may incur additional indebtedness in the future that also bears interest at variable rates. Variable rate debt creates higher debt service requirements if market interest rates increase. Higher debt service requirements could adversely affect our ability to make distributions or payments to our investors and/or cause us to default under certain debt covenants.

        Our degree of leverage could adversely affect our cash flow:    We fund acquisition opportunities and development partially through short-term borrowings (including our revolving credit facility), as well as from proceeds from property sales and undistributed cash. We expect to refinance projects purchased with short-term debt either with long-term indebtedness or equity financing depending upon the economic conditions at the time of refinancing. Our Board of Directors has a general policy of limiting the ratio of our indebtedness to total undepreciated assets (total debt as a percentage of total undepreciated assets) to 50 percent or less, although there is no limit in Mack-Cali Realty, L.P.'s or our organizational documents on the amount of indebtedness that we may incur. However, we have entered into certain financial agreements which contain financial and operating covenants that limit our ability under certain circumstances to incur additional secured and unsecured indebtedness. The Board of Directors could alter or eliminate its current policy on borrowing at any time at its discretion. If this policy were changed, we could become more highly leveraged, resulting in an increase in debt service that could adversely affect our cash flow and our ability to make distributions or payments to our investors and/or could cause an increased risk of default on our obligations.

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        We are dependent on external sources of capital for future growth:    To qualify as a real estate investment trust, we must distribute to our shareholders each year at least 90 percent of our net taxable income, excluding any net capital gain. Because of this distribution requirement, it is not likely that we will be able to fund all future capital needs, including for acquisitions and developments, from income from operations. Therefore, we will have to rely on third-party sources of capital, which may or may not be available on favorable terms or at all. Our access to third-party sources of capital depends on a number of things, including the market's perception of our growth potential and our current and potential future earnings. Moreover, additional equity offerings may result in substantial dilution of our shareholders' interests, and additional debt financing may substantially increase our leverage.

Competition for skilled personnel could increase our labor costs.

        We compete with various other companies in attracting and retaining qualified and skilled personnel. We depend on our ability to attract and retain skilled management personnel who are responsible for the day-to-day operations of our company. Competitive pressures may require that we enhance our pay and benefits package to compete effectively for such personnel. We may not be able to offset such added costs by increasing the rates we charge our tenants. If there is an increase in these costs or if we fail to attract and retain qualified and skilled personnel, our business and operating results could be harmed.

We are dependent on our key personnel whose continued service is not guaranteed.

        We are dependent upon our executive officers for strategic business direction and real estate experience. While we believe that we could find replacements for these key personnel, loss of their services could adversely affect our operations. We have entered into an employment agreement (including non-competition provisions) which provides for a continuous four-year employment term with each of Mitchell E. Hersh, Timothy M. Jones, Barry Lefkowitz and Roger W. Thomas, and a continuous one-year employment term with Michael A. Grossman. We do not have key man life insurance for our executive officers.

Certain provisions of Maryland law and our charter and bylaws as well as our stockholder rights plan could hinder, delay or prevent changes in control.

        Certain provisions of Maryland law, our charter and our bylaws, as well as our stockholder rights plan have the effect of discouraging, delaying or preventing transactions that involve an actual or threatened change in control. These provisions include the following:

        Classified Board of Directors:    Our Board of Directors is divided into three classes with staggered terms of office of three years each. The classification and staggered terms of office of our directors make it more difficult for a third party to gain control of our board of directors. At least two annual meetings of stockholders, instead of one, generally would be required to affect a change in a majority of the board of directors.

        Removal of Directors:    Under our charter, subject to the rights of one or more classes or series of preferred stock to elect one or more directors, a director may be removed only for cause and only by the affirmative vote of at least two-thirds of all votes entitled to be cast by our stockholders generally in the election of directors.

        Number of Directors, Board Vacancies, Term of Office:    We have, in our bylaws, elected to be subject to certain provisions of Maryland law which vest in the Board of Directors the exclusive right to determine the number of directors and the exclusive right, by the affirmative vote of a majority of the remaining directors, even if the remaining directors do not constitute a quorum, to fill vacancies on the board. These provisions of Maryland law, which are applicable even if other provisions of Maryland law

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or the charter or bylaws provide to the contrary, also provide that any director elected to fill a vacancy shall hold office for the remainder of the full term of the class of directors in which the vacancy occurred, rather than the next annual meeting of stockholders as would otherwise be the case, and until his or her successor is elected and qualifies.

        Stockholder Requested Special Meetings:    Our bylaws provide that our stockholders have the right to call a special meeting only upon the written request of the stockholders entitled to cast not less than a majority of all the votes entitled to be cast by the stockholders at such meeting.

        Advance Notice Provisions for Stockholder Nominations and Proposals:    Our bylaws require advance written notice for stockholders to nominate persons for election as directors at, or to bring other business before, any meeting of stockholders. This bylaw provision limits the ability of stockholders to make nominations of persons for election as directors or to introduce other proposals unless we are notified in a timely manner prior to the meeting.

        Exclusive Authority of the Board to Amend the Bylaws:    Our bylaws provide that our board of directors has the exclusive power to adopt, alter or repeal any provision of the bylaws or to make new bylaws. Thus, our stockholders may not effect any changes to our bylaws.

        Preferred Stock:    Under our charter, our Board of Directors has authority to issue preferred stock from time to time in one or more series and to establish the terms, preferences and rights of any such series of preferred stock, all without approval of our stockholders.

        Duties of Directors with Respect to Unsolicited Takeovers:    Maryland law provides protection for Maryland corporations against unsolicited takeovers by limiting, among other things, the duties of the directors in unsolicited takeover situations. The duties of directors of Maryland corporations do not require them to (a) accept, recommend or respond to any proposal by a person seeking to acquire control of the corporation, (b) authorize the corporation to redeem any rights under, or modify or render inapplicable, any stockholders rights plan, (c) make a determination under the Maryland Business Combination Act or the Maryland Control Share Acquisition Act, or (d) act or fail to act solely because of the effect of the act or failure to act may have on an acquisition or potential acquisition of control of the corporation or the amount or type of consideration that may be offered or paid to the stockholders in an acquisition. Moreover, under Maryland laws the act of directors of a Maryland corporation relating to or affecting an acquisition or potential acquisition of control is not subject to any higher duty or greater scrutiny than is applied to any other act of a director. Maryland law also contains a statutory presumption that an act of a director of a Maryland corporation satisfies the applicable standards of conduct for directors under Maryland law.

        Ownership Limit:    In order to preserve our status as a real estate investment trust under the Code, our charter generally prohibits any single stockholder, or any group of affiliated stockholders, from beneficially owning more than 9.8 percent of our outstanding capital stock unless our Board of Directors waives or modifies this ownership limit.

        Maryland Business Combination Act:    The Maryland Business Combination Act provides that unless exempted, a Maryland corporation may not engage in business combinations, including mergers, dispositions of 10 percent or more of its assets, certain issuances of shares of stock and other specified transactions, with an "interested stockholder" or an affiliate of an interested stockholder for five years after the most recent date on which the interested stockholder became an interested stockholder, and thereafter unless specified criteria are met. An interested stockholder is generally a person owning or controlling, directly or indirectly, 10 percent or more of the voting power of the outstanding stock of the Maryland corporation. Our board of directors has exempted from this statute business combinations between the Company and certain affiliated individuals and entities. However, unless our board adopts

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other exemptions, the provisions of the Maryland Business Combination Act will be applicable to business combinations with other persons.

        Maryland Control Share Acquisition Act: Maryland law provides that "control shares" of a corporation acquired in a "control share acquisition" shall have no voting rights except to the extent approved by a vote of two-thirds of the votes eligible to cast on the matter under the Maryland Control Share Acquisition Act. "Control Shares" means shares of stock that, if aggregated with all other shares of stock previously acquired by the acquirer, would entitle the acquirer to exercise voting power in electing directors within one of the following ranges of the voting power: one-tenth or more but less than one-third, one-third or more but less than a majority or a majority or more of all voting power. A "control share acquisition" means the acquisition of control shares, subject to certain exceptions.

        If voting rights of control shares acquired in a control share acquisition are not approved at a stockholder's meeting, then subject to certain conditions and limitations, the issuer may redeem any or all of the control shares for fair value. If voting rights of such control shares are approved at a stockholder's meeting and the acquirer becomes entitled to vote a majority of the shares of stock entitled to vote, all other stockholders may exercise appraisal rights. Our bylaws contain a provision exempting from the Maryland Control Share Acquisition Act any acquisitions of shares by certain affiliated individuals and entities, any directors, officers or employees of the Company and any person approved by the board of directors prior to the acquisition by such person of control shares. Any control shares acquired in a control share acquisition which are not exempt under the foregoing provisions of our bylaws will be subject to the Maryland Control Share Acquisition Act.

        Stockholder Rights Plan:    We have adopted a stockholder rights plan that may discourage any potential acquirer from acquiring more than 15 percent of our outstanding common stock since, upon this type of acquisition without approval of our board of directors, all other common stockholders will have the right to purchase a specified amount of common stock at a substantial discount from market price.

Consequences of failure to qualify as a real estate investment trust could adversely affect our financial condition.

        Failure to maintain ownership limits could cause us to lose our qualification as a real estate investment trust:    In order for us to maintain our qualification as a real estate investment trust, not more than 50 percent in value of our outstanding stock may be actually and/or constructively owned by five or fewer individuals (as defined in the Internal Revenue Code to include certain entities). We have limited the ownership of our outstanding shares of our common stock by any single stockholder to 9.8 percent of the outstanding shares of our common stock. Our Board of Directors could waive this restriction if they were satisfied, based upon the advice of tax counsel or otherwise, that such action would be in our best interests and would not affect our qualifications as a real estate investment trust. Common stock acquired or transferred in breach of the limitation may be redeemed by us for the lesser of the price paid and the average closing price for the 10 trading days immediately preceding redemption or sold at the direction of us. We may elect to redeem such shares of common stock for limited partnership units, which are nontransferable except in very limited circumstances. Any transfer of shares of common stock which, as a result of such transfer, causes us to be in violation of any ownership limit will be deemed void. Although we currently intend to continue to operate in a manner which will enable us to continue to qualify as a real estate investment trust, it is possible that future economic, market, legal, tax or other considerations may cause our Board of Directors to revoke the election for us to qualify as a real estate investment trust. Under our organizational documents, our Board of Directors can make such revocation without the consent of our stockholders.

        In addition, the consent of the holders of at least 85 percent of Mack-Cali Realty, L.P.'s partnership units is required: (i) to merge (or permit the merger of) us with another unrelated person,

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pursuant to a transaction in which Mack-Cali Realty, L.P. is not the surviving entity; (ii) to dissolve, liquidate or wind up Mack-Cali Realty, L.P.; or (iii) to convey or otherwise transfer all or substantially all of Mack-Cali Realty, L.P.'s assets. As general partner, we own approximately 80.9 percent of Mack-Cali Realty, L.P.'s outstanding partnership units (assuming conversion of all preferred limited partnership units).

        Tax liabilities as a consequence of failure to qualify as a real estate investment trust:    We have elected to be treated and have operated so as to qualify as a real estate investment trust for federal income tax purposes since our taxable year ended December 31, 1994. Although we believe we will continue to operate in such manner, we cannot guarantee that we will do so. Qualification as a real estate investment trust involves the satisfaction of various requirements (some on an annual and some on a quarterly basis) established under highly technical and complex tax provisions of the Internal Revenue Code. Because few judicial or administrative interpretations of such provisions exist and qualification determinations are fact sensitive, we cannot assure you that we will qualify as a real estate investment trust for any taxable year.

        If we fail to qualify as a real estate investment trust in any taxable year, we will be subject to the following:

•

we will not be allowed a deduction for dividends paid to shareholders;



•

we will be subject to federal income tax at regular corporate rates, including any alternative minimum tax, if applicable; and



•

unless we are entitled to relief under certain statutory provisions, we will not be permitted to qualify as a real estate investment trust for the four taxable years following the year during which we were disqualified.

        A loss of our status as a real estate investment trust could have an adverse effect on us. Failure to qualify as a real estate investment trust also would eliminate the requirement that we pay dividends to our stockholders.

        Other tax liabilities:    Even if we qualify as a real estate investment trust, we are subject to certain federal, state and local taxes on our income and property and, in some circumstances, certain other state and local taxes. In addition, our taxable REIT subsidiaries will be subject to federal, state and local income tax for income received in connection with certain non-customary services performed for tenants and/or third parties.

        Risk of changes in the tax law applicable to real estate investment trusts:    Since the Internal Revenue Service, the United States Treasury Department and Congress frequently review federal income tax legislation, we cannot predict whether, when or to what extent new federal tax laws, regulations, interpretations or rulings will be adopted. Any of such legislative action may prospectively or retroactively modify our and Mack-Cali Realty, L.P.'s tax treatment and, therefore, may adversely affect taxation of us, Mack-Cali Realty, L.P., and/or our investors.

AVAILABLE INFORMATION

        The Company's internet website is www.mack-cali.com. The Company makes available free of charge on or through its website its annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) of the Securities Exchange Act of 1934, as amended, as soon as reasonably practicable after it electronically files or furnishes such materials to the Securities and Exchange Commission. In addition, the Company's internet website includes other items related to corporate governance matters, including, among other things, the Company's corporate governance guidelines, charters of various committees of the Board of Directors, and the Company's code of business conduct and ethics

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applicable to all employees, officers and directors. Copies of these documents may be obtained, free of charge, from our internet website. Any shareholder also may obtain copies of these documents, free of charge, by sending a request in writing to: Mack-Cali Investor Relations Department, 11 Commerce Drive, Cranford, NJ 07016-3501.

DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

        The Company considers portions of this information to be forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934. The Company intends such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 21E of the Exchange Act. Such forward-looking statements relate to, without limitation, the Company's future economic performance, plans and objectives for future operations and projections of revenue and other financial items. Forward-looking statements can be identified by the use of words such as "may," "will," "should," "expect," "anticipate," "estimate," "continue" or comparable terminology. Forward-looking statements are inherently subject to risks and uncertainties, many of which the Company cannot predict with accuracy and some of which the Company might not even anticipate. Although the Company believes that the expectations reflected in such forward-looking statements are based upon reasonable assumptions at the time made, it can give no assurance that its expectations will be achieved. Future events and actual results, financial and otherwise, may differ materially from the results discussed in the forward-looking statements. Readers are cautioned not to place undue reliance on these forward-looking statements. Among the factors about which the Company has made assumptions are changes in the general economic climate; conditions, including those affecting industries in which the Company's principal tenants compete; any failure of the general economy to recover from the current economic downturn; the extent of any tenant bankruptcies; the Company's ability to lease or re-lease space at current or anticipated rents; changes in the supply of and demand for office, office/flex and industrial/warehouse properties; changes in interest rate levels; changes in operating costs; the Company's ability to obtain adequate insurance, including coverage for terrorist acts; the availability of financing; and other risks associated with the development and acquisition of properties, including risks that the development may not be completed on schedule, that the tenants will not take occupancy or pay rent, or that development or operating costs may be greater than anticipated. For further information on factors which could impact the Company and the statements contained herein, see the "Risk Factors" section. The Company assumes no obligation to update and supplement forward-looking statements that become untrue because of subsequent events.

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ITEM 2. PROPERTIES

PROPERTY LIST

        As of December 31, 2003, the Company's Consolidated Properties consisted of 252 in-service office, office/flex and industrial/warehouse properties, as well as two stand-alone retail properties and two land leases. The Consolidated Properties are located primarily in the Northeast. The Consolidated Properties are easily accessible from major thoroughfares and are in close proximity to numerous amenities. The Consolidated Properties contain a total of approximately 27.0 million square feet, with the individual properties ranging from 6,216 to 977,225 square feet. The Consolidated Properties, managed by on-site employees, generally have attractively landscaped sites, atriums and covered parking in addition to quality design and construction. The Company's tenants include many service sector employers, including a large number of professional firms and national and international businesses. The Company believes that all of its properties are well-maintained and do not require significant capital improvements.

Property Listing

Office Properties

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Property Listing

Office Properties

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Property Listing

Office Properties

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Property Listing

Office Properties

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Property Listing

Office Properties