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Table of Contents
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-K
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2023
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: 1-13087 (Boston Properties, Inc.)
Commission File Number: 0-50209 (Boston Properties Limited Partnership)
BOSTON PROPERTIES, INC.
BOSTON PROPERTIES LIMITED PARTNERSHIP
(Exact name of Registrants as specified in its charter)
Boston Properties, Inc.Delaware04-2473675
(State or other jurisdiction of incorporation or organization)(I.R.S. Employer Identification Number)
Boston Properties Limited PartnershipDelaware04-3372948
(State or other jurisdiction of incorporation or organization)(I.R.S. Employer Identification Number)
Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199-8103
(Address of principal executive offices) (Zip Code)
(617) 236-3300
(Registrants’ telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:
RegistrantTitle of each classTrading Symbol(s)Name of each exchange on which registered
Boston Properties, Inc.Common Stock, par value $.01 per shareBXPNew York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act:
RegistrantTitle of each class
Boston Properties Limited Partnership
Units of Limited Partnership
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    
Boston Properties, Inc.:    Yes      No          Boston Properties Limited Partnership:    Yes      No              
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    
Boston Properties, Inc.:    Yes       No          Boston Properties Limited Partnership:    Yes       No      


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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.    
Boston Properties, Inc.:    Yes      No          Boston Properties Limited Partnership:    Yes      No          
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
Boston Properties, Inc.:    Yes      No          Boston Properties Limited Partnership:    Yes      No      
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Boston Properties, Inc.:    
Large Accelerated Filer           Accelerated Filer          Non-accelerated Filer           Smaller Reporting Company  
Emerging Growth Company  
Boston Properties Limited Partnership:
Large Accelerated Filer           Accelerated Filer           Non-accelerated Filer             Smaller Reporting Company           
Emerging Growth Company  
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards pursuant to Section 13(a) of the Exchange Act.
Boston Properties, Inc. ☐  Boston Properties Limited Partnership ☐ 
Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.
Boston Properties, Inc. Boston Properties Limited Partnership
If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements
of the registrant included in the filing reflect the correction of an error to previously issued financial statements.
Boston Properties, Inc.   Boston Properties Limited Partnership  
Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).
Boston Properties, Inc. ☐  Boston Properties Limited Partnership ☐ 
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    
Boston Properties, Inc.:    Yes  ☐   No          Boston Properties Limited Partnership:    Yes  ☐    No      
As of June 30, 2023, the aggregate market value of the 156,498,046 shares of Common Stock held by non-affiliates of Boston Properties, Inc. was $9,012,722,469 based upon the last reported sale price of $57.59 per share on the New York Stock Exchange on June 30, 2023. (For this computation, Boston Properties, Inc. has excluded the market value of all shares of Common Stock reported as beneficially owned by executive officers and directors of Boston Properties, Inc.; such exclusion shall not be deemed to constitute an admission that any such person is an affiliate of Boston Properties, Inc.).
As of February 20, 2024, there were 157,010,980 shares of Common Stock of Boston Properties, Inc. outstanding.
Because no established market for common units of limited partnership of Boston Properties Limited Partnership exists, there is no market value for such units.
Certain information contained in Boston Properties Inc.’s Proxy Statement relating to its Annual Meeting of Stockholders to be held May 22, 2024 is incorporated by reference in Items 10, 11, 12, 13 and 14 of Part III. Boston Properties, Inc. intends to file such Proxy Statement with the Securities and Exchange Commission not later than 120 days after the end of its fiscal year ended December 31, 2023.


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EXPLANATORY NOTE
This report combines the Annual Reports on Form 10-K for the fiscal year ended December 31, 2023 of Boston Properties, Inc. and Boston Properties Limited Partnership. Unless stated otherwise or the context otherwise requires, references to “BXP” mean Boston Properties, Inc., a Delaware corporation and real estate investment trust (“REIT”), and references to “BPLP” and the “Operating Partnership” mean Boston Properties Limited Partnership, a Delaware limited partnership. BPLP is the entity through which BXP conducts substantially all of its business and owns, either directly or through subsidiaries, substantially all of its assets. BXP is the sole general partner and also a limited partner of BPLP. As the sole general partner of BPLP, BXP has exclusive control of BPLP’s day-to-day management. Therefore, unless stated otherwise or the context requires, references to the “Company,” “we,” “us” and “our” mean collectively BXP, BPLP and those entities/subsidiaries consolidated by BXP.
As of December 31, 2023, BXP owned an approximate 89.4% ownership interest in BPLP. The remaining approximate 10.6% interest was owned by limited partners. The other limited partners of BPLP (1) contributed their direct or indirect interests in properties to BPLP in exchange for common units of limited partnership interest in BPLP or (2) received long-term incentive plan units of BPLP pursuant to BXP’s Stock Option and Incentive Plans, or both. Under the limited partnership agreement of BPLP, unitholders may present their common units of BPLP for redemption at any time (subject to restrictions agreed upon at the time of issuance of the units that may restrict such right for a period of time, generally one year from issuance). Upon presentation of a common unit for redemption, BPLP must redeem the unit for cash equal to the then value of a share of BXP’s common stock. In lieu of a cash redemption by BPLP, however, BXP may elect to acquire any common units so tendered by issuing shares of BXP common stock in exchange for the common units. If BXP so elects, its common stock will be exchanged for common units on a one-for-one basis. This one-for-one exchange ratio is subject to specified adjustments to prevent dilution. BXP generally expects that it will elect to issue its common stock in connection with each such presentation for redemption rather than having BPLP pay cash. With each such exchange or redemption, BXP’s percentage ownership in BPLP will increase. In addition, whenever BXP issues shares of its common stock other than to acquire common units of BPLP, BXP must contribute any net proceeds it receives to BPLP and BPLP must issue to BXP an equivalent number of common units of BPLP. This structure is commonly referred to as an umbrella partnership REIT, or UPREIT.
The Company believes that combining the Annual Reports on Form 10-K of BXP and BPLP into this single report:
enhances investors’ understanding of BXP and BPLP by enabling them to view the business as a whole in the same manner as management views and operates the business;
eliminates duplicative disclosure and provides a more concise and readable presentation because a substantial portion of the disclosure applies to both BXP and BPLP; and
creates time and cost efficiencies through the preparation of one combined report instead of two separate reports.
The Company believes it is important to understand the few differences between BXP and BPLP in the context of how BXP and BPLP operate as a consolidated company. The financial results of BPLP are consolidated into the financial statements of BXP. BXP does not have any other significant assets, liabilities or operations, other than its investment in BPLP, nor does it have employees of its own. BPLP, not BXP, generally executes all significant business relationships other than transactions involving the securities of BXP. BPLP holds substantially all of the assets of BXP, including ownership interests in subsidiaries and joint ventures. BPLP conducts the operations of the business and is structured as a partnership with no publicly traded equity. Except for the net proceeds from equity issuances by BXP, which are contributed to the capital of BPLP in exchange for common or preferred units of partnership in BPLP, as applicable, BPLP generates all remaining capital required by the Company’s business. These sources include working capital, net cash provided by operating activities, borrowings under its credit facilities, the issuance of secured and unsecured debt and equity securities and proceeds received from the disposition of certain properties and interests in joint ventures.
Shareholders’ equity, partners’ capital and noncontrolling interests are the main areas of difference between the consolidated financial statements of BXP and BPLP. The limited partners of BPLP are accounted for as partners’ capital in BPLP’s financial statements and as noncontrolling interests in BXP’s financial statements. The noncontrolling interests in BPLP’s financial statements include the interests of unaffiliated partners in various consolidated partnerships. The noncontrolling interests in BXP’s financial statements include the same


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noncontrolling interests in BPLP and limited partners of BPLP. The differences between shareholders’ equity and partners’ capital result from differences in the equity issued by each of BXP and BPLP.
In addition, the consolidated financial statements of BXP and BPLP differ in total real estate assets resulting from previously applied acquisition accounting by BXP for the issuance of common stock in connection with non-sponsor redemptions of common units of BPLP. This accounting resulted in a step-up of the real estate assets of BXP at the time of such redemptions, resulting in a difference between the net real estate of BXP as compared to BPLP of approximately $242.9 million, or 1.2% at December 31, 2023, and a corresponding difference in depreciation expense, impairment losses and gains on sales of real estate upon the sale of these properties having an allocation of the real estate step-up. The acquisition accounting was nullified on a prospective basis beginning in 2009 as a result of the Company’s adoption of a new accounting standard requiring any subsequent redemptions to be accounted for solely as an equity transaction.
To help investors better understand the key differences between BXP and BPLP, the following items in this report present information separately for BXP and BPLP:
Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities;
Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations and Liquidity and Capital Resources, includes information specific to each entity, where applicable;
Item 8. Financial Statements and Supplementary Data which includes the following specific disclosures for BXP and BPLP:
Note 2. Summary of Significant Accounting Policies;
Note 3. Real Estate;
Note 11. Stockholders’ Equity / Partners’ Capital;
Note 12. Segment Information; and
Note 13. Earnings Per Share / Common Unit;

Item 15. Financial Statement Schedule—Schedule 3.

This report also includes separate Part II, Item 9A. Controls and Procedures, as well as separate Exhibit 23 consents of the independent registered public accounting firm and Exhibits 31 and 32 certifications for each of BXP and BPLP.


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Summary of Risk Factors
The risk factors detailed in Item 1A titled “Risk Factors” in this Annual Report on Form 10-K are the risks that we believe are material to our investors and a reader should carefully consider them. Those risks are not all of the risks we face and other factors not presently known to us or that we currently believe are immaterial may also affect our business if they occur. The following is a summary of the risk factors detailed in Item 1A:
Our performance depends upon the economic conditions, particularly the supply and demand characteristics, of our markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.
Market and economic volatility due to adverse economic and geopolitical conditions, health crises or dislocations in the credit markets could have a material adverse effect on our results of operations, financial condition and ability to pay dividends and/or distributions.
Our success depends on key personnel whose continued service is not guaranteed.
Our performance and value are subject to risks associated with our real estate assets and with the real estate industry, including, without limitation:
potential difficulties or delays renewing leases or re-leasing space;
potential adverse effects from major clients’ bankruptcies or insolvencies;
potential sustained changes in client preferences and space utilization from full-time, collective in-person work environments to hybrid or remote work models, which could decrease overall demand for workplaces and cause market rental rates and property values to be negatively impacted;
potential delays in completion of development and redevelopment projects due to supply chain disruptions and labor shortages; and
potential increases in costs to maintain, renovate and develop our properties related to inflation.
We face potential adverse effects from major clients’ bankruptcies or insolvencies.
Our actual costs to develop properties may exceed our budgeted costs.
Our use of joint ventures may limit our control over and flexibility with jointly owned investments and other assets we may wish to acquire.
We face risks associated with the use of debt to fund acquisitions and developments, including refinancing risk.
Sustained increases in interest rates would increase our interest costs on variable rate debt and could adversely impact our ability to re-finance existing debt or sell assets on favorable terms or at all.
Covenants in our debt agreements could adversely affect our financial condition.
Our degree of leverage could limit our ability to obtain additional financing or affect the market price of our equity and debt securities.
We face risks associated with security breaches, incidents, and compromises through cyber attacks, cyber intrusions or otherwise, as well as other significant disruptions of our information technology (IT) networks and related systems.
We face risks associated with climate change and severe weather events, as well as the regulatory efforts intended to reduce the effects of climate change.
Potential liability for environmental contamination could result in substantial costs.
Some potential losses are not covered by insurance.
Our involvement in legal proceedings and other claims may result in substantial monetary and other costs that have a material adverse effect on our results of operations.
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We face risks associated with BXP’s status as a real estate investment trust (REIT), including, without limitation:
failure to qualify as a REIT would cause BXP to be taxed as a corporation, which would substantially reduce funds available for payment of dividends;
possible adverse state and local tax audits and changes in state and local tax laws could result in increased tax costs that could adversely affect our financial condition and results of operations and the amount of cash available for the payment of dividends and distributions to our securityholders; and
in order to maintain BXP’s REIT status, we may be forced to borrow funds during unfavorable market conditions.
This section contains forward-looking statements. You should refer to the explanation of the qualifications and limitations on forward-looking statements beginning on page 58.
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PART I

Item 1. Business

General
BXP, a Delaware corporation, is a fully integrated, self-administered and self-managed REIT, and is one of the largest publicly-traded office REITs (based on total market capitalization as of December 31, 2023) in the United States that develops, owns and manages primarily premier workplaces. BXP was formed in 1997 to succeed the real estate development, redevelopment, acquisition, management, operating and leasing businesses associated with the predecessor company founded by Mortimer B. Zuckerman and Edward H. Linde in 1970.
Our properties are concentrated in six dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. At December 31, 2023, we owned or had joint venture interests in a portfolio of 188 commercial real estate properties, aggregating approximately 53.3 million net rentable square feet of primarily premier workplaces, including 10 properties under construction/redevelopment totaling approximately 2.7 million net rentable square feet. As of December 31, 2023, our properties consisted of: 
167 office and life sciences properties (including seven properties under construction/redevelopment);
14 retail properties (including two properties under construction/redevelopment);
six residential properties (including one property under construction); and
one hotel.
We consider premier workplaces to be well-located buildings that are modern structures or have been modernized to compete with newer buildings and are professionally managed and maintained. As such, these properties attract creditworthy clients and command upper-tier rental rates. Our definition of premier workplaces may be different than those used by other companies.
We are a full-service real estate company, with substantial in-house expertise and resources in acquisitions, development, financing, capital markets, construction management, property management, marketing, leasing, accounting, risk management, tax and legal services. For this reason, we refer to our tenants as “clients” due to the many facets of our continuous engagements with them, which span beyond the usual tenant/landlord relationship. Throughout this Annual Report, we use the terms “tenant” and “client” interchangeably.
BXP manages BPLP as its sole general partner. Our principal executive office and Boston regional office are located at The Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199 and our telephone number is (617) 236-3300. In addition, we have regional offices at 2800 28th Street, Suite 170, Santa Monica, California 90405, 599 Lexington Avenue, New York, New York 10022, Four Embarcadero Center, San Francisco, California 94111, 1001 Fourth Avenue, Seattle, Washington 98154 and 2200 Pennsylvania Avenue NW, Washington, DC 20037.
Our internet address is http://www.bxp.com. On our website, you can obtain free copies of our Annual Reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, including exhibits, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission, or the SEC. You may also obtain BXP’s and BPLP’s reports by accessing the EDGAR database at the SEC’s website at http://www.sec.gov, or we will furnish an electronic or paper copy of these reports free of charge upon written request to: Investor Relations, Boston Properties, Inc., Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199. “Boston Properties” is a registered trademark, BXP is a registered trademark, and the “bxp” logo is a registered trademark, in all cases, owned by BPLP.
Boston Properties Limited Partnership
BPLP is a Delaware limited partnership organized in 1997, and the entity through which BXP conducts substantially all of its business and owns, either directly or through subsidiaries, substantially all of its assets. BXP is the sole general partner of BPLP and, as of February 20, 2024, the owner of approximately 89.1% of the economic interests in BPLP. Economic interest was calculated as the number of common partnership units of BPLP owned by BXP as a percentage of the sum of (1) the actual aggregate number of outstanding common partnership units of BPLP and (2) the number of common units issuable upon conversion of all outstanding long term incentive plan units of BPLP (“LTIP Units”), for which all performance conditions have been satisfied for such conversion. We exclude from (1) and (2) above other LTIP Units issued in the form of Multi-Year Long-Term Incentive Plan Awards in
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2022 or later (“MYLTIP Awards”), which remain subject to performance conditions. An LTIP Unit is generally the economic equivalent of a share of BXP’s restricted common stock, although LTIP Units issued in the form of MYLTIP Awards are only entitled to receive one-tenth (1/10th) of the regular quarterly distributions (and no special distributions) prior to being earned.
Transactions During 2023
Acquisition
On December 14, 2023, we acquired our joint venture partner’s 45% interest in the joint venture entity that owns Santa Monica Business Park located in Santa Monica, California. Santa Monica Business Park is a 47-acre office park consisting of 21 buildings totaling approximately 1.2 million net rentable square feet. Approximately 70% of the rentable square footage is subject to a ground lease with 75 years remaining, including renewal periods. The ground lease provides the right to purchase the land underlying the properties in 2028 with subsequent purchase rights every 15 years (See Note 4 to the Consolidated Financial Statements). The property is subject to existing mortgage indebtedness of $300.0 million that bears interest at a variable rate equal to the Secured Overnight Financing Rate (“SOFR”) plus 1.38% per annum and matures on July 19, 2025. Upon acquisition, BPLP assumed interest rate swap contracts with notional amounts aggregating $300.0 million to fix SOFR, the reference rate for the mortgage loan, at a weighted-average fixed interest rate of approximately 2.679% per annum for a period that ends on April 1, 2025. These interest rate swap contracts were entered into to reduce the exposure to the variability in future cash flows attributable to changes in the interest rate associated with the mortgage loan (See Notes 7 and 8 to the Consolidated Financial Statements). The acquisition was completed for a gross purchase price of $38.0 million, and we acquired net working capital, including cash and cash equivalents of approximately $20 million. Prior to the acquisition, we had a 55% interest in the joint venture and accounted for it under the equity method of accounting. The acquisition resulted in our full ownership of the joint venture such that we now account for its assets, liabilities and operations on a consolidated basis in our financial statements (See Note 3 to the Consolidated Financial Statements).
Developments/Redevelopments
As of December 31, 2023, we had 10 properties under construction/redevelopment, which we expect will total approximately 2.7 million net rentable square feet when completed. We estimate our share of the aggregate total investment to complete these projects is approximately $2.4 billion, of which approximately $1.3 billion remained to be invested as of December 31, 2023. The total development pipeline, inclusive of office, laboratory/life sciences and retail developments, but excluding Skymark - Reston Next Residential, is 53% pre-leased as of February 20, 2024. For a detailed list of the properties under construction/redevelopment see “Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations.”
On January 5, 2023, we commenced the development of 290 Binney Street, an approximately 566,000 net rentable square foot laboratory/life sciences project in Cambridge, Massachusetts. Concurrently with the commencement of this project, the Kendall Center Blue Parking Garage was taken out of service and demolished to support the development of this project. 290 Binney Street is 100% pre-leased to AstraZeneca. There can be no assurance that we will complete development of the project on the terms and schedule currently contemplated or at all. On November 13, 2023, we entered into agreements to sell a 45% interest in each of 290 Binney Street and 300 Binney Street to an institutional investor (see below transaction for disclosures concerning 300 Binney Street). This interest sale of 290 Binney Street is expected to close in 2024. There can be no assurance that we will complete the interest sale of 290 Binney Street on the terms currently contemplate or at all.
On January 30, 2023, we commenced the redevelopment of 300 Binney Street at Kendall Center in Cambridge, Massachusetts. 300 Binney Street consisted of an approximately 195,000 net rentable square foot premier workplace that is being redeveloped into approximately 236,000 net rentable square feet of laboratory/life sciences space. BXP and BPLP recognized approximately $11.0 million of depreciation expense during the year ended December 31, 2023 associated with the acceleration of depreciation on the assets being removed from service and demolished as part of the redevelopment of the property. The project is 100% pre-leased to the Broad Institute. On November 13, 2023, we entered into agreements to sell a 45% interest in each of 290 Binney Street and 300 Binney Street to an institutional investor (see above transaction for disclosures concerning 290 Binney Street). Upon entry into each of the agreements, we completed the sale of a 45% interest in 300 Binney Street. The institutional investor funded approximately $212.9 million in cash at closing for its investment in 300 Binney Street, including future costs to fund completion of the development project. We will retain a 55% ownership
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interest in the joint venture and fund all remaining costs of the development (See Note 10 to the Consolidated Financial Statements).
On April 29, 2023, we completed and fully placed in-service 2100 Pennsylvania Avenue, a premier workplace project with approximately 476,000 net rentable square feet located in Washington, DC.
On June 1, 2023, we completed and fully placed in-service View Boston observatory at The Prudential Center, a redevelopment of the top three floors of 800 Boylston Street - The Prudential Center, located in Boston, Massachusetts. View Boston observatory at The Prudential Center consists of approximately 63,000 net rentable square feet of retail, including food and beverage, and observation space.
On July 20, 2023, we completed and fully placed in-service 140 Kendrick Street - Building A, a premier workplace redevelopment project with approximately 104,000 net rentable square feet located in Needham, Massachusetts. The property is the first net-zero, carbon-neutral office repositioning of its scale in Massachusetts.
On September 26, 2023, we partially placed in-service 180 CityPoint, an approximately 329,000 net rentable square feet laboratory/life sciences project located in Waltham, Massachusetts.
On October 5, 2023, we partially placed in-service 103 CityPoint, an approximately 113,000 net rentable square feet laboratory/life sciences project located in Waltham, Massachusetts.
On November 30, 2023, we elected to suspend redevelopment on 105 Carnegie Center located in Princeton, New Jersey and as a result ceased capitalization on the project. 105 Carnegie Center was a premier workplace that consisted of approximately 70,000 net rentable square feet that was being redeveloped into approximately 73,000 net rentable square feet of laboratory/life sciences space.
Leases
On August 1, 2023, a consolidated joint venture in which we have a 55% interest executed an up to 99-year ground lease with the Metropolitan Transportation Authority for an approximately 25,000 square foot site, the 343 Madison Avenue project in New York City. The 343 Madison Avenue project contemplates the construction of (1) a direct entrance to the Long Island Railroad’s new east side access project (Grand Central Madison) (“Phase 1”) and (2) an approximately 900,000 square foot premier workplace building with ground floor retail (“Phase 2”). The joint venture has the option until July 31, 2025 to terminate the ground lease prior to construction of the new building and receive reimbursement of up to $117.0 million for the cost of the construction of Phase 1 (See Notes 4 and 10 to the Consolidated Financial Statements). There can be no assurance that Phase 1 will be completed on the terms currently contemplated or that Phase 2 of the development project will commence on the terms currently contemplated or at all.
Secured Debt
On October 26, 2023, we closed on a mortgage loan collateralized by our 325 Main Street, 355 Main Street, 90 Broadway and Cambridge East Garage (also known as Kendall Center Green Garage) properties located in Cambridge, Massachusetts. The mortgage loan has a principal amount of $600.0 million, bears interest at a variable rate of Daily Compounded SOFR plus 2.25% per annum and matures on October 26, 2028. On December 7, 2023, BPLP entered into interest rate swap contracts with notional amounts aggregating $600.0 million to fix Daily Compounded SOFR, the reference rate for the mortgage, at a weighted-average fixed interest rate of 3.7925% for the period commencing on December 15, 2023 and ending on October 26, 2028, for an all-in rate of 6.04% per annum (See Notes 7 and 8 to the Consolidated Financial Statements). BPLP entered into these interest rate swap contracts to reduce its exposure to the variability in future cash flows attributable to changes in the interest rate associated with this mortgage loan. 325 Main Street, 355 Main Street and 90 Broadway are three premier workplaces that aggregate approximately 898,000 net rentable square feet.
Unsecured Debt
On January 4, 2023, BPLP entered into an unsecured credit agreement which provided for a single borrowing of up to $1.2 billion (the “2023 Unsecured Term Loan”). Upon entry into the credit agreement, BPLP exercised its option to draw $1.2 billion under the 2023 Unsecured Term Loan, a portion of which was used to repay in full the $730.0 million unsecured term loan drawn by BPLP in May 2022 (the “2022 Unsecured Term Loan”), which was scheduled to mature on May 16, 2023. There was no prepayment penalty associated with the repayment of the 2022 Unsecured Term Loan. Under the credit agreement, BPLP may, at any time prior to the maturity date,
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increase total commitments by up to an additional $300.0 million in aggregate principal amount by increasing the existing 2023 Unsecured Term Loan or incurring one or more additional term loans, in each case, subject to syndication of the increase and other conditions. The 2023 Unsecured Term Loan matures on May 16, 2024, with one 12-month extension option, subject to customary conditions.
As of December 31, 2023, the 2023 Unsecured Term Loan bore interest at a rate equal to adjusted Term SOFR plus 0.85%. On May 2, 2023, BPLP executed interest rate swaps in notional amounts aggregating $1.2 billion. These interest rate swaps were entered into to fix Term SOFR, the reference rate, at a weighted-average interest rate of 4.6420% for the period commencing on May 4, 2023 and ending on May 16, 2024 (See Notes 7 and 8 to the Consolidated Financial Statements). At December 31, 2023, BPLP had $1.2 billion outstanding under the 2023 Unsecured Term Loan.
On May 15, 2023, BPLP completed a public offering of $750.0 million in aggregate principal amount of its 6.500% unsecured senior notes due 2034. The notes were priced at 99.697% of the principal amount to yield an effective rate (including financing fees) of approximately 6.619% per annum to maturity. The notes will mature on January 15, 2034, unless earlier redeemed. The aggregate net proceeds from the offering were approximately $741.3 million after deducting underwriting discounts and transaction expenses.
On June 1, 2023, BPLP amended its $1.5 billion unsecured credit facility (the “2021 Credit Facility”) to replace the London interbank offered rate (“LIBOR”)-based daily floating rate option with a SOFR-based daily floating rate option and to add options for SOFR-based term floating rates and rates for alternative currency loans. In addition, the amendment added a SOFR credit spread adjustment of 0.10%. On September 28, 2023, BPLP exercised the accordion feature of the 2021 Credit Facility which allowed BPLP to increase the total commitment by up to $500.0 million, subject to syndication of the increase and other conditions (the “Accordion”). BPLP exercised a portion of the Accordion with three new lenders to the 2021 Credit Facility (“New Lenders”). Each of the New Lenders entered into a lender agreement with BPLP to provide an aggregate of $315.0 million in additional revolving credit commitments, which increased the maximum borrowing amount under the 2021 Credit Facility from $1.5 billion to $1.815 billion. All other terms of the 2021 Credit Facility remain unchanged (See Note 7 to the Consolidated Financial Statements).
On September 1, 2023, BPLP completed the repayment of $500.0 million in aggregate principal amount of its 3.125% unsecured senior notes due September 1, 2023. The repayment price was approximately $507.8 million, which was equal to the stated principal plus approximately $7.8 million of accrued and unpaid interest to, but not including, the repayment date. Excluding the accrued and unpaid interest, the repayment price was equal to the principal amount being repaid.
Equity Transactions
During the year ended December 31, 2023, BXP acquired an aggregate of 102,699 common units of limited partnership interest, including a total of 94,863 common units issued upon the conversion of LTIP Units, 2012 outperformance plan awards (“2012 OPP Units”) and 2013 - 2017 multi-year, long-term incentive program awards, presented by the holders for redemption, in exchange for an equal number of shares of BXP common stock.
Investments in Unconsolidated Joint Ventures
On January 31, 2023, we acquired a 50% interest in a joint venture that owns 13100 and 13150 Worldgate Drive located in Herndon, Virginia for a gross purchase price of approximately $17.0 million. The acquisition was completed with available cash. 13100 and 13150 Worldgate Drive consists of two vacant office buildings aggregating approximately 350,000 rentable square feet and a 1,200-space structured parking deck situated on a 10-acre site. The joint venture intends to redevelop the property for residential use. There can be no assurance that the joint venture will commence the development as currently contemplated or at all.
On April 21, 2023, a joint venture in which we own a 50% interest exercised an option to extend the maturity date of the construction loan collateralized by its 7750 Wisconsin Avenue property. Prior to the extension, the loan had a total commitment amount of approximately $252.6 million, bore interest at a variable rate equal to LIBOR plus 1.25% per annum and was scheduled to mature on April 26, 2023, with two, one-year extension options, subject to certain conditions. The extended loan continued to bear interest at LIBOR plus 1.25% per annum through June 1, 2023 after which, the interest rate was converted to a variable rate equal to Term SOFR plus 1.35% per annum. The extended loan now matures on April 26, 2024, with a one-year extension option, subject to certain conditions (See Note 17 to the Consolidated Financial Statements). 7750 Wisconsin Avenue is a premier workplace with approximately 736,000 net rentable square feet located in Bethesda, Maryland.
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On June 5, 2023, a joint venture in which we own a 30% interest repaid the existing construction loan collateralized by its 500 North Capitol Street, NW property and obtained new mortgage loans with related parties. At the time of the repayment, the outstanding balance of the loan totaled approximately $105.0 million and the loan was scheduled to mature on June 6, 2023. The new mortgage loans have an aggregate principal balance of $105.0 million, bear interest at a weighted average fixed rate of 6.83% per annum and mature on June 5, 2026. Our portion of the mortgage loans, $10.5 million, has been reflected as a Related Party Note Receivable on our Consolidated Balance Sheets. We have recognized interest income of approximately $0.6 million for the year ended December 31, 2023. 500 North Capitol Street, NW is an approximately 231,000 net rentable square foot premier workplace in Washington, DC.
On June 28, 2023, a joint venture in which we own a 25% interest exercised an option to extend by 30 days the maturity date of the loan collateralized by its 3 Hudson Boulevard property. At the time of the extension, the loan had an outstanding balance of $80.0 million, bore interest at a variable rate equal to LIBOR plus 3.50% per annum and was scheduled to mature on July 13, 2023, with two extension options (30 days and 180 days, respectively), subject to certain conditions. Following the extension, the modified loan was scheduled to mature on August 13, 2023, with one 180-day extension option, subject to certain conditions. The extended loan continued to bear interest at a variable rate equal to LIBOR plus 3.50% per annum for the period from June 28, 2023 through July 6, 2023. For the period commencing on July 7, 2023 through the maturity date, the modified loan bears interest at a variable rate equal to Term SOFR plus approximately 3.61% per annum. On August 11, 2023, the joint venture exercised its second extension option of 180-days. The extended loan now matures on February 9, 2024 (See Note 17 to the Consolidated Financial Statements). As of December 31, 2023, the loan had approximately $28.0 million of accrued interest due at the maturity date. 3 Hudson Boulevard consists of land and improvements held for future development located in New York, New York.
On July 28, 2023, a joint venture in which we have a 50% interest modified and exercised an option to extend by one year the maturity date of its loan collateralized by 100 Causeway Street. At the time of the modification and extension, the loan had an outstanding balance totaling approximately $340.6 million, bore interest at Term SOFR plus 1.60% per annum, and was scheduled to mature on September 5, 2023. Following the modification and extension, the loan had an outstanding balance of $336.6 million, which included an approximately $4.0 million principal repayment, bears interest at Term SOFR plus 1.48% per annum, and matures on September 5, 2024, with an additional one-year extension option, subject to certain conditions. 100 Causeway Street is an approximately 634,000 net rentable square foot premier workplace located in Boston, Massachusetts and is approximately 95% leased.
On September 1, 2023, a joint venture in which we have a 49% interest completed and fully placed in-service 751 Gateway, an approximately 231,000 net rentable square foot laboratory/life sciences project in South San Francisco, California. The property is 100% leased.
On September 6, 2023, a joint venture in which we have a 50% interest modified the loan collateralized by its Hub on Causeway - Podium property. At the time of the modification, the loan had an outstanding balance of approximately $174.3 million, bore interest at Term SOFR plus 2.35% per annum, and was scheduled to mature on September 6, 2023. Following the modification, the modified loan had an outstanding balance of $154.3 million, which included an approximately $20.0 million principal repayment, bore interest at Daily SOFR plus 2.50% per annum, and matures on September 8, 2025, with a one-year extension option, subject to certain conditions. On September 8, 2023, the joint venture entered into interest rate swap contracts with notional amounts aggregating approximately $154.3 million through September 2, 2025, resulting in a fixed interest rate of approximately 7.35% per annum through the expiration of the interest rate swap contracts. The Hub on Causeway - Podium is an approximately 383,000 net rentable square foot premier workplace located in Boston, Massachusetts and is approximately 94% leased.
On September 13, 2023, a joint venture in which we owned a 20% equity interest completed the first step of a two-step restructuring of its ownership in Metropolitan Square. Step one of the restructuring resulted in, among other things, (i) the cessation of our obligation to fund future investments through our then 20% equity interest, which resulted in the recognition of a gain on investment of approximately $35.8 million related to our deficit investment balance, and (ii) the removal of the property from our in-service portfolio. On October 2, 2023, step two of the restructuring was completed and included (i) the sale of the property and assignment of the outstanding mortgage to the new owner, and (ii) the closing of a new mezzanine loan where we are a co-lender of up to $20.0 million (“New Mezz Loan”). The New Mezz Loan may be drawn upon for future lease-up, operating and other costs on an as needed basis, and amounts borrowed will bear interest at a per annum rate of 12%, compounded monthly. As of December 31, 2023, we have funded approximately $1.7 million. In addition, we will continue to provide
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property management and leasing services to the property with the potential to earn additional incentive fees. Metropolitan Square is an approximately 657,000 net rentable square foot premier workplace located at 655 15th Street, NW in the heart of downtown Washington, DC.
On October 31, 2023, a joint venture in which we have a 50% interest modified the lease of a third-party hotel developer/operator at its Hub on Causeway – Hotel Air Rights property. The third-party hotel developer/operator paid $4.5 million in connection with this modification to fulfill its obligation to repay the joint venture’s investment. This modification resulted in a reassessment of the lease classification per Accounting Standards Codification (“ASC”) 842. Based on this reassessment this lease was reclassified as a sales-type lease. The joint venture recorded a sales-type lease receivable of approximately $18.6 million. In addition, the joint venture recorded a gain on sales-type lease of approximately $2.7 million associated with the derecognition of the asset.
On December 14, 2023, we completed the acquisition of our joint venture partner’s 45% ownership interest in the joint venture that owns Santa Monica Business Park for a purchase price of $38.0 million, and we acquired net working capital, including cash and cash equivalents of approximately $20 million (see “Acquisition” above). Prior to the acquisition, we had a 55% ownership interest in the joint venture and accounted for it under the equity method of accounting. The acquisition resulted in us having full ownership of the joint venture such that we now account for the assets, liabilities, and operations of it on a consolidated basis in our financials statements instead of under the equity method of accounting and as a result we recognized a gain on consolidation of approximately $29.9 million.
On December 14, 2023, we completed the acquisition of our joint venture partner’s approximate 29% ownership interest in the joint venture that owns 360 Park Avenue South for a purchase price of $1, increasing our ownership in the joint venture to approximately 71%. We also assumed the partner’s share of the joint venture’s cash and working capital aggregating approximately $25.4 million, as well as the partner’s share of the outstanding $220.0 million mortgage debt. 360 Park Avenue South, a 20-story, approximately 450,000 square foot premier workplace, is currently under re-development.
During the year ended December 31, 2023, we recognized an other-than-temporary impairment loss on our investments in Platform 16, 360 Park Avenue South, 200 Fifth Avenue and Safeco Plaza of approximately $155.2 million, $54.0 million, $33.4 million and $29.9 million, respectively (See Note 6 to the Consolidated Financial Statements).
Noncontrolling Interest
On July 28, 2023, we entered into a joint venture agreement with an institutional investor for the future development of 343 Madison Avenue located on Madison Avenue between 44th and 45th Streets in New York City, New York adjacent to Grand Central Station. Prior to the formation of the joint venture, we and the institutional investor were engaged in a collaborative arrangement. We own a 55% interest in the joint venture and our partner owns a 45% interest, and we will provide customary development, property management, and leasing services. The joint venture partner contributed approximately $4.8 million in cash and $17.5 million in improvements and prepaid ground rent for its 45% ownership interest in the joint venture. We contributed approximately $5.9 million in cash and $21.4 million in improvements and prepaid ground rent for our 55% ownership interest in the joint venture (See Note 4 to the Consolidated Financial Statements).
Stock Option and Incentive Plan
On January 25, 2023, BXP’s Compensation Committee approved a new equity-based, multi-year, long-term incentive program (the “2023 MYLTIP”) as a performance-based component of our overall compensation program under the Boston Properties, Inc. 2021 Stock Incentive Plan (the “2021 Plan”) to certain executive officers of BXP, effective February 7, 2023. Under ASC 718 “Compensation - Stock Compensation,” the 2023 MYLTIP awards have an aggregate value of approximately $13.1 million, which amount will generally be amortized into earnings under the graded vesting method (See Note 15 to the Consolidated Financial Statements).
On February 3, 2023, the measurement period for our 2020 MYLTIP awards ended and, based on BXP’s relative TSR performance, the final payout was determined to be 50% of target, or an aggregate of approximately $3.8 million (after giving effect to employee separations). As a result, an aggregate of 152,460 2020 MYLTIP Units that had been previously granted were automatically forfeited.
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Business and Growth Strategies
Business Strategies
Our primary business objective is to maximize return on investment to provide our investors with the greatest possible total return at all points of the economic cycle. Our strategies to achieve this objective are:
to target a few carefully selected dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC—and to be one of the leading, if not the leading, developers, owners and managers in each of those markets with a full-service office in each market providing property management, leasing, development, construction and legal expertise. We select markets and submarkets with a diverse economic base and a deep pool of prospective clients in various industries and where clients have demonstrated a preference for premier workplaces and other facilities. Additionally, our markets have historically been able to recruit new talent to them and as such created job growth that results in growth in rental rates and occupancy over time. We have explored, and may continue to explore for future investment, select domestic and international markets that exhibit these same traits;
to emphasize markets and submarkets within those markets where the difficulty of receiving the necessary approvals for development and the necessary financing constitute high barriers to the creation of new supply, and where skill, financial strength and diligence are required to successfully develop, finance and manage high-quality office and life sciences space, as well as selected retail and residential space;
to take on complex, technically challenging development projects, leveraging the skills of our management team to successfully develop, acquire or reposition properties that other organizations may not have the capacity or resources to pursue;
to own and develop high-quality real estate designed to meet the demands of today’s clients who require sophisticated telecommunications and related infrastructure, support services, sustainable features and amenities, including those amenities that enrich in-person experiences and support a hybrid work environment, and to manage those facilities so as to become the landlord of choice for both existing and prospective clients;
to opportunistically acquire assets that increase our market share in the markets in which we have chosen to concentrate, as well as potential new markets, which exhibit an opportunity to improve returns through repositioning (through a combination of capital improvements and shift in marketing strategy), changes in management focus and leasing;
to explore joint venture or lending opportunities with existing property owners located in desirable locations, who seek to benefit from the depth of development and management expertise we are able to provide and our access to capital;
to pursue on a selective basis the sale of properties or interests therein, including core properties, to either (1) take advantage of the demand for our premier properties and realize the value we have created or (2) pare from our portfolio properties that we believe have slower future growth potential;
to seek third-party development contracts to enable us to retain and utilize our existing development and construction management staff, especially when our internal development is less active or when new development is less-warranted due to market conditions; and
to enhance our capital structure through our access to a variety of sources of capital and proactively manage our debt expirations.
Growth Strategies
External Growth Strategies
We believe that our development experience, our organizational depth, utilization of our joint venture partner relationships and our balance sheet position us to continue to selectively develop a range of premier workplaces, including high-rise urban developments, mixed-use developments (including office, residential and retail), low-rise suburban office properties and life sciences space, within budget and on schedule. We believe we are also well-positioned to achieve external growth through acquisitions. Other factors that contribute to our competitive position include:
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our control of sites (including sites under contract or option to acquire) in our markets that could support approximately 18.9 million additional square feet of new development;
our reputation gained through 54 years of successful operations and the stability and strength of our existing portfolio of properties;
our relationships with leading national corporations, universities and public institutions, including government agencies, seeking new facilities and development services;
our relationships with nationally recognized financial institutions that provide capital to the real estate industry;
our track record and reputation for executing acquisitions efficiently provide comfort to domestic and foreign institutions, private investors and corporations who seek to sell commercial real estate in our market areas;
our ability to act quickly on due diligence and financing;
our relationships with institutional buyers and sellers of high-quality real estate assets;
our ability to procure entitlements from multiple municipalities to develop sites and attract land owners to sell or partner with us; and
our relationship with domestic and foreign investors who seek to partner with companies like ours.
Opportunities to execute our external growth strategy fall into three categories:
Development in selected submarkets. We believe the selected development of well-positioned premier workplaces, including office, life sciences, residential buildings and mixed-use complexes may be justified in our markets. We believe in acquiring land after taking into consideration timing factors relating to economic cycles and in response to market conditions that allow for its development at the appropriate time. While we purposely concentrate in markets with high barriers-to-entry, we have demonstrated throughout our 54-year history, an ability to make carefully timed land acquisitions in submarkets where we can become one of the market leaders in establishing rent and other business terms. We believe that there are opportunities at key locations in our existing and other markets for a well-capitalized developer to acquire land or buildings with development or redevelopment potential.
In the past, we have been particularly successful at acquiring sites or options to purchase sites that need governmental approvals for development. Because of our development expertise, knowledge of the governmental approval process and reputation for quality development with local government regulatory bodies, we generally have been able to secure the permits necessary to allow development and to profit from the resulting increase in land value. We seek complex projects where we can add value through the efforts of our experienced and skilled management team leading to attractive returns on investment.
Our strong regional relationships and recognized development expertise have enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn relatively significant returns on these development opportunities through multiple business cycles.
Acquisition of assets and portfolios of assets from institutions, including lenders, or individuals. We believe that due to our size, management strength and reputation, we are well positioned to acquire portfolios of assets or individual properties from institutions or individuals if valuations meet our criteria. In addition, we believe that our market knowledge and our liquidity and access to capital may provide us with a competitive advantage when pursuing acquisitions. Opportunities to acquire properties may also come through the purchase of first mortgage or mezzanine debt. We are also able to appeal to sellers wishing to contribute on a tax-deferred basis their ownership of property for equity in a diversified real estate operating company that offers liquidity through access to the public equity markets in addition to a quarterly distribution. Our ability to offer common and preferred units of limited partnership in BPLP to sellers who would otherwise recognize a taxable gain upon a sale of assets for cash or BXP’s common stock may facilitate these types of acquisitions on a tax-efficient basis. Existing promulgated Treasury regulations may limit the tax benefits previously available to sellers in some variations of these transactions.
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Acquisition of underperforming assets and portfolios of assets. We believe that because of our in-depth market knowledge and development experience in each of our markets, our national reputation with brokers, financial institutions, owners of real estate and others involved in the real estate market and our access to competitively-priced capital, we are well-positioned to identify and acquire existing, underperforming properties for competitive prices and to add significant additional value to such properties through our effective marketing strategies, repositioning/redevelopment expertise and a responsive property management program.
Internal Growth Strategies
We believe that opportunities will exist to increase cash flow from our existing properties through an increase in occupancy and rental rates because they are of high quality and in desirable locations. Additionally, our markets have diversified economies that have historically experienced job growth and increased use of office space, resulting in growth in rental rates and occupancy over time. Our strategy for maximizing the benefits from these opportunities is three-fold: (1) to provide high-quality property management services using our employees in order to encourage clients to renew, expand and relocate in our properties, (2) to achieve speed and transaction cost efficiency in replacing departing clients through the use of in-house services for marketing, lease negotiation and construction of tenant and capital improvements and (3) to work with new or existing clients with space expansion or contraction needs, leveraging our expertise and clustering of assets to maximize the cash flow from our assets. We expect to continue our internal growth as a result of our ability to:
Cultivate existing submarkets and long-term relationships with credit clients. In choosing locations for our properties, we have paid particular attention to transportation and commuting patterns, physical environment, adjacency to established business centers and amenities, proximity to sources of business growth and other local factors.
The weighted-average lease term of our in-place leases based on square feet, including leases signed by our unconsolidated joint ventures, was approximately 7.8 years at December 31, 2023, and we continue to cultivate long-term leasing relationships with a diverse base of high-quality, financially stable clients. In 2023, we executed approximately 4.2 million square feet of leases with a weighted-average lease term of 8.2 years. Based on leases in place at December 31, 2023, leases with respect to approximately 5.8% of the total square feet in our portfolio, including unconsolidated joint ventures, will expire in calendar year 2024. 
Directly manage our office properties to maximize the potential for client retention. We provide property management services ourselves, rather than contracting for this service, to maintain awareness of and responsiveness to client needs. We and our properties also benefit from cost efficiencies produced by an experienced work force attentive to preventive maintenance and energy management and from our continuing programs to assure that our property management personnel at all levels remain aware of their important role in client relations. In addition, we reinvest in our properties by adding new services and amenities that are desirable to our clients.
Replace clients quickly at best available market terms and lowest possible transaction costs. We believe that we are well-positioned to attract new clients and achieve relatively high rental and occupancy rates as a result of our well-located, well-designed and well-maintained properties, our reputation for high-quality building services and responsiveness to clients, and our ability to offer expansion and relocation alternatives within our submarkets.
Extend terms of existing leases to existing clients prior to expiration. We have also successfully structured early client renewals, which have reduced the cost associated with lease downtime while securing the tenancy of our highest quality credit-worthy clients on a long-term basis and enhancing relationships.
Re-development of existing assets. We believe the select re-development of assets within our portfolio, where through the ability to increase the building size and/or to increase cash flow and generate appropriate returns on incremental investment after consideration of the asset’s current and future cash flows, may be desirable. This generally occurs in situations in which we are able to increase the building’s size, improve building systems, including conversion to higher yielding life sciences uses, and sustainability features, and/or add client amenities, thereby increasing client demand, generating acceptable returns on incremental investment and enhancing the long-term value of the property and the company. In the past, we have been particularly successful at gaining local government approval for
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increased density at several of our assets, providing the opportunity to enhance value at a particular location. Our strong regional relationships and recognized re-development expertise have enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn attractive returns on these development opportunities through multiple business cycles.
Sustainability
Our Strategy
We actively work to promote our growth and operations sustainably and responsibly across our six dynamic gateway markets. BXP’s sustainability strategy is to conduct our business, the development, ownership and operation of new and existing buildings, in a manner that contributes to positive economic, social and environmental outcomes for our clients, shareholders, employees and the communities we serve. Our investment philosophy is shaped by our core strategy of long-term ownership and our commitment to our communities and the centers of commerce and civic life that make them thrive. We are focused on developing and maintaining healthy, high-performance buildings, while simultaneously mitigating operational costs and the potential external impacts of energy, water, waste, greenhouse gas (“GHG”) emissions and climate change. Positive social impact is also of great importance to BXP and our employees, which is exhibited by our commitments to charitable giving, volunteerism, public realm investments and promoting diversity, equity and inclusion in the workplace and our communities. Through these efforts, we demonstrate that operating and developing commercial real estate can be conducted with a conscious regard for the environment and broader society while mutually benefiting our stakeholders.
Sustainability Leadership
We continue to address the needs of our stakeholders by making efforts to maintain and improve our performance across three pillars: climate action, climate resilience and social good. BXP is a widely recognized industry leader in sustainability, and our 2023 highlights include:
BXP ranked among the top real estate companies in the GRESB assessment, earning an eighth consecutive 5-star rating. 2023 was the twelfth consecutive year that BXP earned the GRESB “Green Star” designation
BXP maintained an MSCI rating of “AA” and a CDP score of “B”
BXP was named to Newsweek’s America’s Most Responsible Companies in 2024 for the fourth consecutive year. BXP ranked 58th overall out of the 600 companies and received the highest environmental score within the Real Estate industry
BXP was named a member of the Dow Jones Sustainability Index (DJSI) North America for the third consecutive year. BXP was one of seven real estate companies that qualified and the only office REIT in the index, scoring in the 94th percentile of the real estate companies assessed for inclusion
BXP was recognized at the Bronze Level by Commercial Property Executive for “Best ESG Program”
BXP was named an ENERGY STAR Partner of the Year – Sustained Excellence Award Winner
BXP continued its tenure as an inaugural Platinum Level Green Lease Leader by the Institute for Market Transformation and the U.S. Department of Energy
Our leadership position is due, in part, to our establishment of environmental goals, the periodic reporting of progress toward our goals and the achievement of these goals. We have publicly adopted energy, emissions, water, building certification and waste goals that establish targets aligned with the United Nations Sustainable Development Goals. As of the end of 2022, the combined impacts of efficiency measures and renewable energy consumption resulted in a 39% decrease in energy use intensity and over 70% reduction in Scope 1 and Scope 2 GHG emissions intensity below a 2008 base year. We have also aligned our emissions reduction targets with climate science and in 2020 became the first North American office REIT to establish an emissions reduction target ambition in line with a 1.5°C trajectory, the most ambitious designation available at the time of submission under the Science Based Targets initiative. In April 2021, we affirmed our commitment to achieving carbon-neutral operations (for direct and indirect Scope 1 and Scope 2 GHG emissions) by 2025 from our occupied and actively managed buildings where we have operational control. BXP’s carbon-neutral goal progress and key performance indicator data is updated annually in our Sustainability and Impact Report, published in April.
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We are focused on developing, owning and operating healthy and high-performance buildings. BXP is a corporate member of the U.S. Green Building Council® (“USGBC”) and has a long history of green buildings under USGBC’s Leadership in Energy and Environmental Design™ (LEED®) rating system. As of December 31, 2023, we had LEED-certified 33.4 million square feet of our total in-service portfolio, of which 92% was certified at the highest Gold and Platinum levels. In 2018, we announced a partnership with a leading healthy building certification system, Fitwel, to support healthy building design and operational practices across our portfolio, becoming a Fitwel Champion. We completed our Fitwel Champion commitments and have added 25.0 million square feet of Fitwel-certified buildings across our total in-service portfolio since 2018.
Sustainability Accounting Standards Board (“SASB”) Disclosures
The Real Estate Sustainability Accounting Standard issued by SASB in 2018 proposed sustainability accounting metrics designed for disclosure in mandatory filings, such as the Annual Report on Form 10-K, and serves as the framework against which we have aligned our disclosures for sustainability information. The recommended energy and water management activity metrics for the real estate industry include energy consumption data coverage as a percentage of floor area (“Energy Intensity”); percentage of the eligible portfolio that is certified ENERGY STAR® (“ENERGY STAR certified”); total energy consumed by portfolio area (“Total Energy Consumption”); water withdrawal as a percentage of total floor area (“Water Intensity”); and total water withdrawn by portfolio area (“Total Water Consumption”). Our energy and water data is collected from utility bills and submeters and is assured by an independent, third-party assurance expert, which includes all 2022 SASB energy and water metrics. For more information on the independent, third-party assurance expert and the methodology used to assure the data, refer to “Reporting” below. During the 2022 calendar year, 47 buildings representing 43% of our eligible portfolio were ENERGY STAR certified. A licensed professional has verified all ENERGY STAR applications.
The charts below detail our Energy Intensity, Total Energy Consumption, Water Intensity and Total Water Consumption for 2015 through 2022 for which data were available on occupied and actively managed buildings where we had operational control.1,2,3,4,5,6
https://cdn.kscope.io/c5c2016cc8a40076b259165219b9ae1b-Energy 2022.jpg https://cdn.kscope.io/c5c2016cc8a40076b259165219b9ae1b-Water 2022.jpg
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(1)Full 2023 calendar year energy and water data will not be available and assured by a third party until April 22, 2024. Therefore, 2022 is the most recent year for which complete and third-party assured energy and water data is available.
(2)The charts reflect the performance of our occupied and actively managed portfolio. We define “occupied buildings” as those with no more than 50% vacancy. Actively managed buildings are those over which we have operational control of building system performance and investment decisions. At the end of the 2022 calendar year, our occupied and actively managed portfolio included 96 buildings totaling 42.8 million gross square feet, and it accounted for approximately 77% of BXP’s total in-service portfolio by area.
(3)Floor area is considered to have complete energy consumption data coverage when we obtain energy consumption data (i.e., energy types and amounts consumed) for all types of energy consumed in the relevant floor area during the calendar year, regardless of when such data was obtained.
(4)The scope of energy includes energy purchased from sources external to us and our clients or produced by us or our clients and energy from all sources, including fuel, gas, electricity and steam. Energy use intensity (kBtu/SF) has been weather-normalized.
(5)Water sources include surface water (including water from wetlands, rivers, lakes and oceans), groundwater, rainwater collected directly and stored by BXP, municipal water supplies or supply from other water utilities.
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(6)2020 and 2021 data reflect the combined impacts of efficiency measures, renewable energy and reduced physical occupancy due to the COVID-19 pandemic. Occupancy was not significantly reduced in 2022.
Climate Resilience
As a long-term owner and active manager of real estate assets in operation and under development, we take a long-term view of climate change risks and opportunities. We are focused on understanding how climate change may impact the performance of our portfolio and the steps we can take to increase climate resilience. We continue to evaluate the potential risks associated with climate change that could impact our portfolio and are taking proactive steps to plan for and/or mitigate such risks.
Ø    Governance
As a vertically integrated, full-service real estate company, we are engaged in addressing climate-related issues at all levels of our organization. Our Board of Directors has established a board-level Sustainability Committee to, among other things, increase Board oversight over environmental and sustainability issues, including climate-related risks and opportunities. The Board delegated to the Sustainability Committee the responsibility to oversee BXP’s sustainability program, which includes monitoring and addressing, as needed, environmental-, sustainability- and climate-related risks. Management’s role in assessing and managing climate-related risks, opportunities and initiatives is spread across multiple teams throughout our organization, including our executive leadership and our Sustainability, Risk Management, Development, Construction and Property Management Departments. BXP has a dedicated team of sustainability professionals focused on coordinating and collaborating across corporate and regional teams to advance environmental sustainability issues and initiatives.
Our approach to climate-related issues is also informed by robust stakeholder engagement. We are in frequent dialogue with investors, customers, community members, governmental policymakers, consultants and other non-governmental organizations. We are heavily involved in industry associations and participate in conferences and workshops covering sustainability and climate resilience topics. Through these engagements, we enhance our knowledge of climate-related issues and those issues that are most important to our stakeholders and industry best practices.
Ø    Strategy
We have aligned our climate-related disclosures with the recommendations of the Task Force on Climate-Related Financial Disclosures (“TCFD”). The TCFD framework has informed the development of our strategy for identifying and managing both physical and transition risks associated with climate change. As defined by the TCFD framework, physical risks associated with climate change include acute risks (extreme weather-related events) and chronic risks (such as extreme heat and sea-level rise), and transition risks associated with climate change include policy and legal risks, and other technology, market and reputation-related risks.
We continue to proactively assess the potential risks that may impact the properties in our portfolio, gather information and monitor the evolving regulatory landscape related to climate change. Our process for assessing climate-related risks and their implications on our properties and business includes a climate change scenario analysis that was conducted in 2021 on our portfolio assets and will be updated in 2024. In particular, we engaged Moody’s ESG Solutions (formerly branded as the Four Twenty Seven Application), an independent provider of science-driven insights and analytics on climate risk, for its climate risk scoring to evaluate the forward-looking physical climate risk exposure of our entire portfolio. The scenario analysis and physical risk scoring were based on an RCP 8.5 emissions scenario, which is a worst-case, high-emissions scenario, under a time horizon up to 2040. The scenario analysis included all in-service assets owned by BXP and included climate events such as hurricanes, wildfires, heat, water stress, flooding and sea-level rise. We are also using climate risk data to identify potential risks during the new acquisition diligence process. The analysis of our portfolio in 2021 yielded no material findings.
We consider climate-related risks and opportunities in the context of the following time horizons: short-term (1-2 years), medium-term (3-10 years) and long-term (>10 years). Based on the foregoing process for evaluating climate-related risks, including the scenario analysis, we have identified (1) the following potential physical and transition risks associated with climate change that could impact our portfolio in the future across the stated time horizons and (2) our climate-related opportunities. We will continue to analyze the results of climate risk analyses, including the following risks and opportunities to understand our potential exposure and inform our climate resilience strategy and future investments, which include climate-related risk mitigation and initiatives.
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Time PeriodPhysical Risks
Short- to Medium-Term
Increased severity of extreme weather events, including flooding and wind damage, extreme heat and sea-level rise may cause one or more of the following to occur:
Direct damage to properties
Increased costs of property insurance and snow removal
Supply chain disruption
Costs associated with capital expenditures and infrastructure-related remediation projects
Alteration of designs at new and existing buildings
Increased costs of real estate taxes or other assessments

Long-Term
Building adaptation, including architectural and mechanical improvements, could increase capital expenditure requirements.
Extreme drought and wildfires could adversely impact demand in markets prone to water scarcity and annual wildfire risk.
Sea-level rise and extreme weather events could make property insurance unavailable in high-risk areas.
Public transportation system disruptions could impact access to BXP buildings.
Chronic climate-related physical risks and associated downtime could result in declining demand for office space at impacted buildings.
Time PeriodTransition Risks
Short- to Medium-Term
Non-compliance with regulatory requirements, including energy and carbon performance standards, may increase costs and/or introduce potential fines.
Compliance with green building codes, including electrification of heating systems, may increase development and operational costs.
Failure to meet sustainability needs (e.g., net-zero requirements) of clients and investors could result in lost business.
Additional growth, particularly in life sciences, may increase energy and emissions intensities.
Long-TermReal estate taxes may increase to fund public projects to improve regional and neighborhood-scale resilience.
Time PeriodMitigation & Other Opportunities
Short-Term
Energy and carbon reductions could result in greater product differentiation and competitive advantage.
Stronger sustainability disclosures, particularly regarding climate action and resilience, may qualify BXP for greater inclusion in sustainability ETFs and other funds.
BXP may benefit from a lower cost of capital from green bonds and/or sustainability-linked credit.
BXP may avoid operating cost increases from rising energy costs through actions focused on efficient operations.
Medium-Term
BXP may avoid penalties associated with building energy and carbon performance standards.
Assets may be converted and/or certified net-zero, which may increase demand for office space.
Long-TermBy focusing on the risks of climate change associated with acute and chronic physical risks during the development, acquisition and operating life of assets, BXP may mitigate losses and downtime resulting from extreme weather events.
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Ø    Risk Management
BXP is committed to managing and avoiding the impacts of climate change. Our risk management program includes physical and transition risks, including both climate mitigation (resource efficiency and emissions reduction) and adaptation (integration of climate resilience into our investment decision-making). We are actively acquiring, developing and operating a geographically diverse portfolio of high-quality commercial real estate properties. Individual assets have unique risk profiles and insurance requirements. Through the processes of acquisition, development and operation of our in-service portfolio, our experienced real estate professionals are identifying risks, including business continuity risks, loss exposure related to extreme weather events and impacts of regulation, including permitting requirements, codes, and energy and carbon performance standards. The climate risk profile of each property is largely dependent on the property’s unique attributes, physical location and jurisdictional regulatory requirements.
Asset-Level Risk Management
We carry all-risk property insurance on our properties including those under development. Insurance coverage mitigates the impact on BXP from losses associated with natural catastrophes, such as floods, fires, earthquakes and wind events.
We are preparing for long-term climate risk by considering climate change scenarios and expect that we will continue to assess climate change vulnerabilities resulting from potential future climate scenarios and sea-level rise. We will continue to evaluate existing plans and procedures and proactively implement practical, cost-effective resiliency measures and infrastructure enhancements, including:
Business Continuity Plans
Emergency Response and Life Safety Plans
Emergency Evacuation Planning, Procedures and Drills
Client Engagement and Coordination
Life Safety Analysis
Elevation of vault, switchgear and critical equipment during new development
Waterproofing of subgrade infrastructure
Floodable first floors
Temporary flood barriers
Backup generation, emergency lighting and fire pumps
Onsite energy resources and distributed generation, storage and solar photovoltaic systems.
We are managing transition risks by benchmarking energy, carbon, water and waste performance at the asset level and are prioritizing interventions at underperforming assets. We develop, operate and maintain a large portfolio of buildings that are LEED, ENERGY STAR and/or Fitwel certified. As of December 31, 2023, 91% of our actively managed portfolio was certified under one or more of these frameworks. As a leader in green building, we will continue to make investments in building performance, energy efficiency and decarbonization.
Through our climate action efforts, we believe we can play a leading role in advancing the transition to a low-carbon economy and are taking action to decarbonize operations. GHG sources include the generated electricity and steam at offsite generation facilities, the onsite combustion of fuels (e.g., natural gas), and emissions associated with other business activities, including business travel and new development. We continue to explore and implement creative and cost-effective measures that reduce GHG emissions from our operations.
BXP became a proud signatory of the We Are Still In pledge after the U.S. withdrawal from the Paris Agreement and has aligned emissions reduction targets with climate science. In 2020, the SBTi Target Validation Team classified BXP’s emissions reduction target ambition and determined that it is in line with a 1.5°C trajectory, the most ambitious designation available at the time of submission. We are committed to achieving carbon-neutral operations, or net-zero carbon dioxide equivalent emissions, which includes direct and indirect Scope 1 and Scope 2 GHG emissions, by 2025 from our occupied and actively managed buildings where we have operational control.
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BXP’s Carbon-Neutral Operations Strategy
Our strategy to achieve carbon-neutral operations includes the following goals:
(1)Energy Efficient Operations – Approximately 1/3 of total carbon reductions by 2025 (below a 2008 base year) from energy conservation and efficient operations.
(2)Renewable Energy – Advancement of onsite development of renewable energy systems and sourcing offsite renewable energy to meet 100% of our electricity needs by 2025.
(3)Electrification – Explore and advance electrification, prioritizing electrification of new developments and replacement of onsite gas-fired systems at existing buildings at the end of their useful lives.
(4)Carbon Offsets – To the extent necessary, offset any remaining emissions during the transition to carbon-free energy.
The resilience of our markets may depend on the action taken by cities to adapt transportation, energy, and communication infrastructure for extreme heat, weather events, sea-level rise and flooding. We will continue to encourage the adaptation of our cities and management of physical and transition risks by maintaining a voice in policy decision-making at the local level through direct engagement and/or advocacy through collective membership-based groups.
Ø Metrics
We closely monitor energy consumption and associated GHG emissions and provide a detailed accounting of sustainability key performance indicators in our annual sustainability reporting. As of the end of 2022, the combined impacts of efficiency measures and renewable energy consumption resulted in a 39% decrease in energy use intensity and an over 70% reduction in Scope 1 and Scope 2 GHG emissions intensity below a 2008 base year. BXP’s carbon-neutral commitment includes direct and indirect Scope 1 and Scope 2 GHG emissions from our actively managed portfolio where we have operational control. Scope 1 and Scope 2 GHG emissions include emissions associated with landlord-controlled energy use within our multi-tenant buildings. Scope 1 GHG emissions include all emissions associated with the onsite combustion of fossil fuels for heating, hot water and standby generators. Scope 2 GHG emissions include all emissions associated with the offsite generation of electricity and steam. As our business continues to grow, carbon reduction targets and the transparent disclosure of sustainability metrics will remain a priority.

Reporting
A notable part of our commitment to sustainable development and operations is our commitment to transparent reporting of sustainability performance indicators, as we recognize the importance of this information to investors, lenders and others in understanding how BXP assesses sustainability information and evaluates risks and opportunities. We publish an annual Sustainability & Impact Report that is aligned with the Global Reporting Initiative (GRI) Framework, United Nations Sustainable Development Goals and the SASB Framework. BXP’s Sustainability & Impact Report includes our strategy, key performance indicators, annual like-for-like comparisons and achievements. The report is available on our website at http://www.bxp.com under the heading “Commitment.” Our annual sustainability reports, including all of our energy, water and emissions metrics included therein, are assured by an independent, third-party assurance expert. The assurance expert performs an independent verification for certain of our performance indicators and issues an opinion, which is attached to each sustainability report, that opines on each sustainability report’s inclusiveness, materiality, sustainability context, completeness and reliability.
We have been an active participant in the green bond market since 2018, which provides access to sustainability-focused investors interested in the positive environmental externalities of our business activities. Since 2018, BPLP has issued an aggregate of $5.1 billion of green bonds in six separate offerings. The terms of the green bonds have restrictions that limit our allocation of the net proceeds to “eligible green projects.” We publish Green Bond Allocation Reports disclosing the full or partial allocation, as applicable, of net proceeds from the green bond offerings to eligible green projects. We have published four Green Bond Allocation Reports that have allocated more than $2.7 billion in net proceeds to eligible green projects, with the remaining $823.8 million to be allocated to future eligible green projects pending final LEED certifications. The Green Bond Allocation Reports are available on our website at http://www.bxp.com under the heading “Commitment.”
Except for the documents specifically incorporated by reference into this Annual Report on Form 10-K, the information contained on our website or that can be accessed through our website is not incorporated by reference into this Annual Report on Form 10-K.
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Human Capital Management
Our culture supports and nurtures our employees. Our employees are a significant distinguishing factor that sets BXP apart. As of December 31, 2023, we had 727 non-union employees (we had 836 employees, inclusive of union employees). Except as otherwise noted, all data provided in this Human Capital Management section refers to BXP’s non-union employee workforce as the unions control primary aspects of the hiring process. Our operational and financial performance depends on their talents, energy, experience and well-being. Our ability to attract and retain talented people depends on a number of factors, including work environment, career development and professional training, compensation and benefits, and the health, safety and wellness of our employees. We have an established reputation for excellence and integrity; these core values are inherent in our culture and play a critical role in achieving our goals and overall success.
Diversity, Equity & Inclusion
We strive to create a diverse and inclusive workplace. It has been, and will continue to be, our policy to recruit, hire, assign, promote and train in all job titles without regard to race, national origin, religion, age, color, sex, sexual orientation, gender identity, disability, protected veteran status, or any other characteristic protected by local, state, or federal laws, rules, or regulations. By implementing this policy, we aim to ensure that all employees have the opportunity to make their maximum contribution to us and to their own career goals.
BXP’s Diversity, Equity & Inclusion Council (the “DEI Council”) is an executive-sponsored, employee-led, voluntary committee unified by BXP’s mission to promote diversity, equity, inclusion and transparency as part of our organization’s culture, decision-making practices and business activities, while also providing a mechanism for positive impact in the communities in which we operate. Since its formation in 2020, the DEI Council has grown to over 42 Council members across our six regions, and each member contributes to the overall mission through leadership in one or more of the DEI Council’s three committees – the Employee Engagement Committee, the Supplier Diversity & Engagement Committee and the Community Outreach Committee – and/or four employee resource groups (“ERGs”). Including ERG members, as of December 31, 2023, BXP’s DEI community consisted of 255 members, or 35% of BXP’s workforce.
The DEI Council in collaboration with BXP’s CEO, President and Human Resources Department annually identify actionable diversity goals and propose initiatives to advance its mission. In 2023, the DEI Council’s focus areas were on enhancing: (1) employees’ sense of belonging, (2) DEI education, (3) social responsibility, (4) transparency and communication and (5) governance. Throughout 2023, the DEI Council and BXP’s ERGs executed on numerous initiatives in furtherance of BXP’s DEI mission. BXP’s notable 2023 achievements and DEI successes include:
Belonging
launching BXP’s 4th ERG – VALOR – consisting of BXP’s employee veteran community and its allies with a primary mission of leveraging its members’ shared and unique experiences to champion veteran recruitment, professional growth and development, and outward engagement
celebrating internally among employees and externally with BXP clients across the portfolio important DEI holidays and dates that are significant to BXP’s DEI community
Education
providing consultant-led training to BXP’s employees and numerous companywide opportunities for exposure to DEI topics and experiences
sponsoring instructional sessions for DEI Council members to enhance the effectiveness of DEI leadership positions
Social Responsibility
renewing BXP’s depository relationship with the nation’s largest Black-led bank
continuing BXP’s positive track record of engaging underrepresented business enterprises (“UBEs”) defined as minority-, women-, disabled-, LGBTQ+-, and/or veteran- owned businesses, increasing UBE partnerships by 6% year-over-year and UBE spend by 12% year-over-year
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Transparency & Communication
using multiple internal and external platforms to discuss and promote BXP’s DEI initiatives, achievements and future programming, including via BXP companywide Town Hall discussion, BXP-hosted webcast to BXP’s investor community and a presentation to the Board of Directors led by the Co-Chairs of the DEI Council
creating official branding for the DEI Council and each of its ERGs
Governance
adopting charters for the DEI Council and ERGs to formalize protocols, guidelines, and a framework for future iterations of the DEI Council’s members
following a rigorous assessment of the DEI Council’s objectives, execution and effectiveness conducted by the DEI Co-Chairs, developing a robust 2024 schedule of DEI initiatives informed by the assessments and employee feedback.

Diversity, Equity & Inclusion at BXP(1)
TOTAL WORKFORCE(2)(3)
MANAGER & ABOVE(2)(3)
BOARD OF DIRECTORS
590259035904
59065907 5909
 _______________
(1) As of December 31, 2023. We determine race and gender based voluntary self-identification at onboarding and as voluntarily updated throughout the year.
(2) Represents percentages for all of our employees including intern employees but excluding union employees for which the unions control primary aspects of the hiring process; percentages do not include BXP’s non-employee directors.
(3) “Other” represents American Indian/Alaskan Native, Native Hawaiian or Other Pacific Islander, two or more races and those that did not voluntarily self-identify.
Culture & Employee Engagement
We believe that the success of our business is tied to the quality of our workforce, and we strive to maintain a corporate environment without losing the entrepreneurial spirit with which we were founded more than 50 years ago.
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By providing a quality workplace and comprehensive benefit programs, we recognize the commitment of our employees to bring their talent, energy and experience to us. Our continued success is attributable to our employees’ expertise and dedication. Our workforce, as referred to in this section, excludes intern employees and union employees for which the unions control primary aspects of the hiring process.
We periodically conduct employee engagement surveys to monitor our employees’ satisfaction in different aspects of their employment, including company performance, leadership, communication, career development and benefits offerings. Past employee responsiveness to the engagement surveys has been consistently high and the results help inform us on matters that our employees view as key contributors to a positive work experience. We intend to continue to periodically evaluate employee engagement as needed on a meaningful basis.
Another indicator of the success of our efforts in the workplace is the long tenure of our employees, 33% of whom have worked at BXP for ten or more years. The average tenure of our employees is approximately 9.2 years and that of our officers is 18.5 years. In 2023, our voluntary workforce turnover rate was 10.4%.
Career Development & Training
We invest significant resources in our employees’ personal and professional growth and development and provide a wide range of tools and development opportunities that build and strengthen employees’ leadership and professional skills. These development opportunities include in-person and virtual training sessions, in-house learning opportunities, various management trainings, departmental conferences, executive townhalls and external programs. We foster an environment of growth and internal promotion and strive for a best-in-class candidate experience for our internal applicants. Open positions are posted, and employees are highly encouraged to apply for promotion within the organization. For 2023, 12% of our employees were promoted to elevated roles within our organization. Of the employees promoted, 51% were women and 28% were ethnically diverse.
Compensation & Benefits
We designed our compensation program with the goal of providing a balanced and effective way of ensuring internal equity and market competitiveness in our pay practices. We have coupled external, market-driven data with an equitable performance review assessment tool to strike the balance that best represents our compensation strategy and links pay to performance. On an annual basis, our Human Resources department evaluates market compensation ranges for each position to ensure we are appropriately compensating our top performers. We believe this total rewards program directly aligns with our compensation and benefits strategy.
Our employee benefit programs are designed to meet the needs of our diverse workforce, support our employees and their families by offering comprehensive and competitive programs that provide flexibility and choice in coverage, make available valuable resources to protect and enhance financial security and help balance work and personal life. Some of the benefits that we offer our employees include:
health (including telehealth), dental and vision insurance,
a 401(k) plan with a generous matching contribution,
an employee stock purchase plan,
health care and dependent care flexible spending accounts,
income protection through our sick pay, salary continuation and long-term disability policies and life insurance,
a scholarship program for the children of non-officer employees,
a commuter subsidy to support the use of public transportation,
tuition reimbursement,
paid vacation, holiday, personal and volunteer days and paid parental leave to balance work and personal life,
wellness and mental health wellbeing programs,
back-up child and elder care, and
pet insurance.
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Health, Safety & Wellness
As one of the largest publicly traded premier workplace REITs (based on total market capitalization as of December 31, 2023) in the United States, we are keenly aware of the influence of buildings on human health and its importance to our clients and employees. The health, safety and security of our employees, clients, contractors and others are our highest priority. We have implemented numerous operational measures to address health and safety in our buildings, including measures related to indoor air quality in our buildings. For example, we have (i) installed indoor air quality monitoring devices across approximately 40 buildings that continue to provide real-time indoor air quality data, (ii) maintain enhanced air filtration in buildings and (iii) continue to conduct air and water quality testing.
We believe the success of our employees is dependent upon their overall well-being, including their physical health, mental health, work-life balance and financial well-being. In addition to the benefits outlined above, we also offer our employees an Employee Wellness Program, an Employee Assistance Program and a Mental Health Well-Being Program. The Employee Wellness Program was established in 2016 to encourage employees to improve their health and well-being by offering a variety of activities and engaging content to meet individual wellness goals. Program participants receive a reduction in their health insurance deduction cost. The Employee Assistance Program includes services for childcare, eldercare, personal relationship information, financial planning assistance, stress management, mental illness and general wellness and self-help. BXP offers a premium mental health program that provides online resources and support for employees facing a wide variety of issues.
Policies with Respect to Certain Activities
The discussion below sets forth certain additional information regarding our investment, financing and other policies. These policies have been determined by BXP’s Board of Directors and, in general, may be amended or revised from time to time by the Board of Directors.
Investment Policies
Investments in Real Estate or Interests in Real Estate
Our investment objectives are to provide quarterly cash dividends/distributions to our securityholders and to achieve long-term capital appreciation through increases in our value. We have not established a specific policy regarding the relative priority of these investment objectives.
We expect to continue to pursue our investment objectives primarily through the ownership of our current properties, development and redevelopment projects and other acquired properties. We currently intend to continue to invest primarily in developments of properties and acquisitions of existing improved properties or properties in need of redevelopment, and acquisitions of land that we believe have development potential, primarily in our existing markets of Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. We have explored and may continue to explore for future investment in select domestic and international markets that exhibit these same traits. Future investment or development activities will not be limited to a specified percentage of our assets. We intend to engage in such future investment or development activities in a manner that is consistent with the maintenance of BXP’s status as a REIT for federal income tax purposes. In addition, we may purchase or lease income-producing commercial and other types of properties for long-term investment, expand and improve the real estate presently owned or other properties purchased, or sell such real estate properties, in whole or in part, when circumstances warrant. We do not have a policy that restricts the amount or percentage of assets that will be invested in any specific property, however, our investments may be restricted by our debt covenants.
We may also continue to participate with third parties in property ownership, through joint ventures or other types of co-ownership. These investments may permit us to own interests in larger assets without unduly restricting diversification and, therefore, add flexibility in structuring our portfolio.
Equity investments may be subject to existing mortgage financing and other indebtedness or such financing or indebtedness as may be incurred in connection with acquiring or refinancing these investments. Debt service on such financing or indebtedness will have a priority over any distributions with respect to BXP’s common stock. Investments are also subject to our policy not to be treated as an investment company under the Investment Company Act of 1940, as amended (the “1940 Act”). 
Investments in Real Estate Mortgages and Mezzanine Debt
While our current portfolio consists primarily of, and our business objectives emphasize, equity investments in commercial real estate, we may, at the discretion of the Board of Directors of BXP, invest in mortgages and other
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types of real estate interests consistent with BXP’s qualification as a REIT. Investments in real estate mortgages run the risk that one or more borrowers may default under such mortgages and that the collateral securing such mortgages may not be sufficient to enable us to recoup our full investment. We may invest in participating, convertible or traditional mortgages if we conclude that we may benefit from the cash flow, or any appreciation in value of the property or as an entrance to the fee ownership. As of December 31, 2023, we had one note receivable and two related party note receivables outstanding, which totaled approximately $92.2 million, after adjustments for financing costs and the current expected credit loss allowance.
Securities of or Interests in Entities Primarily Engaged in Real Estate Activities
Subject to the percentage of ownership limitations and gross income and asset tests necessary for BXP’s REIT qualification, we also may invest in securities of other REITs, other entities engaged in real estate activities or securities of other issuers, including for the purpose of exercising control over such entities.
Dispositions
We decide to dispose or partially dispose of properties based upon the periodic review of our portfolio and the determination by the Board of Directors of BXP that doing so is in our best interests. Any decision to dispose of a property will be authorized by the Board of Directors of BXP or a committee thereof. Some holders of limited partnership interests in BPLP could incur adverse tax consequences upon the sale of certain of our properties that differ from the tax consequences to BXP. Consequently, holders of limited partnership interests in BPLP may have different objectives regarding the appropriate pricing and timing of any such sale. Such different tax treatment derives in most cases from the fact that we acquired these properties in exchange for partnership interests in contribution transactions structured to allow the prior owners to defer taxable gain. Generally, this deferral continues so long as we do not dispose of the properties in a taxable transaction. Unless a sale by us of these properties is structured as a like-kind exchange under Section 1031 of the Internal Revenue Code of 1986, as amended (the “Code”), or in a manner that otherwise allows deferral to continue, recognition of the deferred tax gain allocable to these prior owners is generally triggered by a sale. As of December 31, 2023, we had one property that was subject to a tax protection agreement, which may limit our ability to dispose of the asset or require us to pay damages to the prior owner in the event of a taxable sale in violation of the agreement. The tax protection agreement expires on December 14, 2033, or earlier if certain conditions by the prior owner are met.
Financing Policies 
The agreement of limited partnership of BPLP and BXP’s certificate of incorporation and bylaws do not limit the amount or percentage of indebtedness that we may incur. Further, we do not have a policy limiting the amount of indebtedness that we may incur, nor have we established any limit on the number or amount of mortgages that may be placed on any single property or on our portfolio as a whole. However, our mortgages, credit facilities, joint venture agreements and unsecured debt securities contain customary restrictions, requirements and other limitations on our ability to incur indebtedness. In addition, we evaluate the impact of incremental leverage on our debt metrics and the credit ratings of BPLP’s publicly traded debt. A reduction in BPLP’s credit ratings could result in us borrowing money at higher interest rates.
The Board of Directors of BXP will consider a number of factors when evaluating our level of indebtedness and when making decisions regarding the incurrence of indebtedness, including the purchase price of properties to be acquired with debt financing, the estimated market value of our properties upon refinancing, the cost and effectiveness of entering into interest rate swaps, caps, floors and other interest rate hedging contracts and the ability of particular properties and us as a whole to generate cash flow to cover expected debt service. 
Policies with Respect to Other Activities
As the sole general partner of BPLP, BXP has the authority to issue additional common and preferred units of limited partnership interest of BPLP. BXP has issued, and may in the future issue, common or preferred units of limited partnership interest to persons who contribute their direct or indirect interests in properties to us in exchange for such common or preferred units. We have not engaged in trading, underwriting or agency distribution or sale of securities of issuers other than BXP and BPLP does not intend to do so. At all times, we intend to make investments in such a manner as to enable BXP to maintain its qualification as a REIT, unless, due to changes in circumstances or to the Code, the Board of Directors of BXP determines that it is no longer in the best interest of BXP to qualify as a REIT. We may make loans to third parties, including, without limitation, to joint ventures in which we participate or in connection with the disposition of a property. We intend to make investments in such a way that
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we will not be treated as an investment company under the 1940 Act. Our policies with respect to these and other activities may be reviewed and modified or amended from time to time by the Board of Directors of BXP. 
Governmental Regulations
General
Compliance with various governmental regulations has an impact on our business, including our capital expenditures, earnings and competitive position, which can be material. We incur costs to monitor and take actions to comply with governmental regulations that are applicable to our business, which include, among others, (1) federal securities laws and regulations, (2) applicable stock exchange requirements, and (3) federal, state and local laws and regulations related to (a) our status as a REIT and other tax laws and regulations, and (b) real property, the improvements thereon and the operation thereof, such as laws and regulations relating to the environment, health and safety, zoning, usage, building, fire and life safety codes, (4) the requirements of the Office of Foreign Assets Control of the United States Department of the Treasury and (5) the Americans with Disabilities Act of 1990. In addition to the discussion below, see “Item 1A. – Risk Factors” for a discussion of these governmental regulations and other material risks to us, including, to the extent material, to our competitive position, and see “Item 7— Management’s Discussion and Analysis of Financial Condition and Results of Operations” together with our consolidated financial statements, including the related notes included therein, for a discussion of material information relevant to an assessment of our financial condition and results of operations, including, to the extent material, the effects that compliance with governmental regulations may have upon our capital expenditures and earnings.
Environmental Matters
It is our policy to retain independent environmental consultants to conduct or update Phase I environmental assessments (which generally do not involve invasive techniques such as soil or ground water sampling) and asbestos surveys in connection with our acquisition of properties. These pre-purchase environmental assessments have not revealed environmental conditions that we believe will have a material adverse effect on our business, assets, financial condition, results of operations or liquidity, and we are not otherwise aware of environmental conditions with respect to our properties that we believe would have such a material adverse effect. However, from time to time environmental conditions at our properties have required and may in the future require environmental testing and/or regulatory filings, as well as remedial action. 
For example, in February 1999, we (through a joint venture) acquired from Exxon Corporation a property in Massachusetts that was formerly used as a petroleum bulk storage and distribution facility and was known by the state regulatory authority to contain soil and groundwater contamination. We developed an office park on the property. We engaged a specially licensed environmental consultant to oversee the management of contaminated soil and groundwater that was disturbed in the course of construction. Under the property acquisition agreement, Exxon agreed to (1) bear the liability arising from releases or discharges of oil and hazardous substances which occurred at the site prior to our ownership, (2) continue monitoring and/or remediating such releases and discharges as necessary and appropriate to comply with applicable requirements, and (3) indemnify us for certain losses arising from preexisting site conditions. Any indemnity claim may be subject to various defenses and contractual limitations, including time limits, and there can be no assurance that the amounts paid under the indemnity, if any, would be sufficient to cover the liabilities arising from any such releases and discharges. 
Environmental investigations at some of our properties and certain properties owned by our affiliates have identified groundwater contamination migrating from off-site source properties. In each case we engaged a licensed environmental consultant to perform the necessary investigations and assessments, and to prepare any required submittals to the regulatory authorities. In each case the environmental consultant concluded that the properties qualify under the regulatory program or the regulatory practice for a status which eliminates certain deadlines for conducting response actions at a site. We also believe that these properties qualify for liability relief under certain statutory provisions or regulatory practices regarding upgradient releases. Although we believe that the current or former owners of the upgradient source properties may bear responsibility for some or all of the costs of addressing the identified groundwater contamination, we will take such further response actions (if any) that we deem necessary or advisable. Other than periodic testing at some of these properties, no such additional response actions are anticipated at this time. 
Some of our properties and certain properties owned by our affiliates are located in urban, industrial and other previously developed areas where fill or current or historical use of the areas have caused site contamination. Accordingly, it is sometimes necessary to institute special soil and/or groundwater handling procedures and/or
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include particular building design features in connection with development, construction and other property operations in order to achieve regulatory closure and/or ensure that contaminated materials are addressed in an appropriate manner. In these situations, it is our practice to investigate the nature and extent of detected contamination, including potential issues associated with vapor intrusion concerns and/or potential contaminant migration to or from the subject property in ground water, assess potential liability risks and estimate the costs of required response actions and special handling procedures. We then use this information as part of our decision-making process with respect to the acquisition, deal structure and/or development of the property. For example, we own a parcel in Massachusetts which was formerly used as a quarry/asphalt batching facility. Pre-purchase testing indicated that the site contained relatively low levels of certain contaminants. We have developed an office park on this property. Prior to and during redevelopment activities, we engaged a specially licensed environmental consultant to monitor environmental conditions at the site and prepare necessary regulatory submittals based on the results of an environmental risk characterization. A submittal has been made to the regulatory authorities in order to achieve regulatory closure at this site. The submittal included an environmental deed restriction that mandates compliance with certain protective measures in a portion of the site where low levels of residual soil contamination have been left in place in accordance with applicable laws. 
We expect that resolution of the environmental matters described above will not have a material impact on our business, assets, financial condition, results of operations or liquidity. However, we cannot assure you that we have identified all environmental liabilities at our properties, that all necessary remediation actions have been or will be undertaken at our properties, that we will be indemnified, in full or at all, or that we will have insurance coverage in the event that such environmental liabilities arise. 
Corporate Governance
BXP is currently governed by an eleven-member Board of Directors. The current members of the Board of Directors of BXP are Kelly A. Ayotte, Bruce W. Duncan, Carol B. Einiger, Diane J. Hoskins, Mary E. Kipp, Joel I. Klein, Douglas T. Linde, Matthew J. Lustig, Owen D. Thomas, William H. Walton III, and Derek A. (Tony) West. All directors of BXP stand for election for one-year terms expiring at the next succeeding annual meeting of stockholders.
Owen D. Thomas currently serves as the Chairman of BXP’s Board of Directors and Joel I. Klein serves as our Lead Independent Director. The Board of Directors of BXP also has Audit, Compensation, Nominating and Corporate Governance and Sustainability Committees. The membership of each of these committees is described below.
  Audit Compensation Nominating and
Corporate Governance
Sustainability
Kelly A. AyotteX
Bruce W. DuncanXX(1)X
Carol B. Einiger  X   X
Diane J. HoskinsXX(1)
Mary E. KippX(1)X
Joel I. Klein*     
Douglas T. LindeX
Matthew J. LustigX(1)X
Owen D. Thomas (2)X
William H. Walton IIIX
Derek A. (Tony) WestX
 
*=Lead Independent Director, X=Committee member, (1)=Committee Chair, (2)=Chairman of BXP’s Board of Directors
BXP has the following corporate governance documents and procedures in place:
The Board of Directors has adopted charters for each of its Audit, Compensation and Nominating and Corporate Governance Committees. A copy of each of these charters is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance.”
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The Board of Directors has adopted Corporate Governance Guidelines, a copy of which is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance” with the name “Governance Guidelines.”
The Board of Directors has adopted a Code of Business Conduct and Ethics, which governs business decisions made and actions taken by BXP’s directors, officers and employees. A copy of this code is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance” with the name “Code of Business Conduct and Ethics.” BXP intends to disclose on this website any amendment to, or waiver of, any provisions of this Code applicable to the directors and executive officers of BXP that would otherwise be required to be disclosed under the rules of the SEC or the New York Stock Exchange.
The Board of Directors has established an ethics reporting system that employees may use to anonymously report possible violations of the Code of Business Conduct and Ethics, including concerns regarding questionable accounting, internal accounting controls or auditing matters, by telephone or over the internet.
The Board of Directors has adopted a Policy on our Political Spending, a copy of which is available on our website at http://www.bxp.com under the heading “Investors” and the subheading “Governance” with the name “Policy on Political Spending.”
Competition
We compete in the leasing of premier workplace, retail and residential space with a considerable number of other real estate companies, some of which may have greater marketing and financial resources than are available to us. In addition, our hotel property competes for guests with other hotels, some of which may have greater marketing and financial resources than are available to us and to the manager of our one hotel, Marriott International, Inc. 
Principal factors of competition in our primary business of owning, acquiring and developing premier workplaces are the quality of properties, leasing terms (including rent and other charges and allowances for tenant improvements), attractiveness and convenience of location, the quality and breadth of client services and amenities provided, and reputation as an owner and operator of premier workplaces in the relevant market. Additionally, our ability to compete depends upon, among other factors, trends in the national and local economies, investment alternatives, financial condition and operating results of current and prospective clients, availability and cost of capital, construction and renovation costs, taxes, utilities, governmental regulations, legislation and population trends. 
In addition, we currently have six residential properties (including one under construction) and may in the future decide to acquire or develop additional residential properties. As an owner, we will also face competition for prospective residents from other operators/owners whose properties may be perceived to offer a better location or better amenities or whose rent may be perceived as a better value given the quality, location and amenities that the resident seeks. We will also compete against condominiums and single-family homes that are for sale or rent. Because the scale of our residential portfolio is relatively small, we expect to continue to retain third parties to manage our residential properties.
Our Hotel Property
We operate our hotel property through a taxable REIT subsidiary. The taxable REIT subsidiary, a wholly-owned subsidiary of BPLP, is the lessee pursuant to a lease for the hotel property. As lessor, BPLP is entitled to a percentage of gross receipts from the hotel property. The hotel lease is intended to provide the economic benefits of ownership of the underlying real estate to flow to us as rental income, while our taxable REIT subsidiary earns the profit or loss from operating the property as a hotel. Marriott International, Inc. continues to manage the hotel property under the Marriott name and under terms of the existing management agreements. Marriott has been engaged under a separate long-term incentive management agreement to operate and manage the hotel on behalf of the taxable REIT subsidiary.
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Item 1A. Risk Factors.
Set forth below are the risks that we believe are material to our investors and they should be carefully considered. Throughout this section, we refer to the equity and debt securities of both BXP and BPLP as our “securities,” and the investors who own securities of BXP, BPLP or both, as our “securityholders.” These risks are not all of the risks we face and other factors not presently known to us or that we currently believe are immaterial may also affect our business if they occur. This section contains forward-looking statements. You should refer to the explanation of the qualifications and limitations on forward-looking statements beginning on page 58.
Risks Related to Our Business and Operations
Our performance depends upon the economic conditions, particularly the supply and demand characteristics, of our markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.
Substantially all of our revenue is derived from properties located in six markets: Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. A downturn in the economies of these markets, or the impact that a downturn in the overall national economy may have upon these economies, could result in reduced demand for office space and/or a reduction in rents. Because our portfolio consists primarily of premier workplace buildings (as compared to a more diversified real estate portfolio), a decrease in demand for workplaces in turn could adversely affect our results of operations. Additionally, there are submarkets within our markets that are dependent upon a limited number of industries. For example, in our Washington, DC market, we focus on leasing our properties to governmental agencies and contractors. In our West Coast market, our leasing is focused on clients in the technology and media industries, as well as legal firms. In addition, in our New York market, we have historically leased properties to financial, legal and other professional firms. A reduction in spending by the Federal Government, sustained changes in space utilization due to remote work models, and/or a significant downturn in one or more of the foregoing sectors have resulted in, and could continue to result in, reduced demand for office space and adversely affect our results of operations.
In addition, a significant economic downturn over a period of time could result in an event or change in circumstances that results in an “other than temporary” impairment in the value of our properties or our investments in unconsolidated joint ventures. An “other than temporary” impairment loss is recognized if the carrying amount of the asset (1) is not recoverable over its expected holding period and (2) exceeds its fair value. During the year ended December 31, 2023, we recognized an other-than-temporary impairment loss on our investments in four unconsolidated joint ventures aggregating approximately $272.6 million (See Note 6 to the Consolidated Financial Statements). There can be no assurance that we will not take additional charges in the future related to the impairment of our assets or investments. Any future impairment could have a material adverse effect on our results of operations in the period in which the charge is taken.
Market and economic volatility due to adverse economic and geopolitical conditions, health crises or dislocations in the credit markets could have a material adverse effect on our results of operations, financial condition and ability to pay dividends and/or distributions. 
Our business may be adversely affected by market and economic volatility experienced by the U.S. and global economies, the real estate industry as a whole and/or the local economic conditions in the markets in which our properties are located. Such adverse economic and geopolitical conditions may be due to, among other issues, prolonged labor market challenges impacting the recruitment and retention of talent, continued inflation, high interest rates, volatility in the public equity and debt markets, and international economic and other conditions, including pandemics, geopolitical instability and other conditions beyond our control. These current conditions, or similar conditions existing in the future, may adversely affect our results of operations, financial condition and ability to pay dividends and/or distributions as a result of the following, among other potential consequences: 
the financial condition of our clients may be adversely affected, which may result in client defaults under leases due to bankruptcy, lack of liquidity, lack of funding, operational failures or for other reasons;
significant job losses and/or a sustained shift away from collective in-person work environments or relocations away from the markets in which we operate may occur, which could decrease overall demand for workplaces in the regions in which we operate and cause market rental rates and property values to be negatively impacted;
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tightening labor market conditions may adversely affect our ability to recruit and retain talent, which may result in lack of business continuity and increased costs to address the labor challenges;
our ability to borrow on terms and conditions that we find acceptable, or at all, may be limited, which could reduce our ability to pursue acquisition and development opportunities and refinance existing debt, reduce our returns from our acquisition and development activities and increase our future interest expense;
reduced values of our properties may limit our ability to dispose of assets at attractive prices or to obtain debt financing secured by our properties and may reduce the availability of unsecured loans;
the value and liquidity of our short-term investments and cash deposits could be reduced as a result of a deterioration of the financial condition of the institutions that hold our cash deposits or the institutions or assets in which we have made short-term investments, a dislocation of the markets for our short-term investments, increased volatility in market rates for such investments or other factors;
one or more lenders under our line of credit could refuse to fund their financing commitment to us or could fail and we may not be able to replace the financing commitment of any such lenders on favorable terms, or at all; and
to the extent we enter into derivative financial instruments, one or more counterparties to our derivative financial instruments could default on their obligations to us, or could fail, increasing the risk that we may not realize the benefits of these instruments.
Our success depends on key personnel whose continued service is not guaranteed. 
We depend on the efforts of key personnel, particularly Owen D. Thomas, Chief Executive Officer, Douglas T. Linde, President, and Raymond A. Ritchey, Senior Executive Vice President. Among the reasons that Messrs. Thomas, Linde and Ritchey are important to our success is that each has a national reputation, which attracts business and investment opportunities and assists us in negotiations with lenders, joint venture partners and other investors. If we lost their services, our relationships with lenders, potential clients and industry personnel could diminish.  
Our Chief Financial Officer and Regional Managers also have strong reputations. Their reputations aid us in identifying opportunities, having opportunities brought to us, and negotiating with clients and build-to-suit prospects. While we believe that we could find replacements for these key personnel, the loss of their services could materially and adversely affect our operations because of diminished relationships with lenders, prospective clients and industry personnel. 
Risks Related to Real Estate
Our performance and value are subject to risks associated with our real estate assets and with the real estate industry.
Our economic performance and the value of our real estate assets, and consequently the value of our securities, are subject to the risk that if our properties do not generate revenues sufficient to meet our operating expenses, including debt service and capital expenditures, our cash flow and ability to pay distributions to our securityholders will be adversely affected. The following factors, among others, may adversely affect the income generated by our properties:
downturns in the national, regional and local economic conditions (particularly increases in unemployment);
changes in client preferences and space utilization from full-time, collective in-person work environments to hybrid or remote work models, which could decrease overall demand for workplaces and cause market rental rates and property values to be negatively impacted;
competition from other office, life sciences, hotel, retail and residential buildings;
local real estate market conditions, such as oversupply or reduction in demand for office, life sciences, hotel, retail or residential space;
changes in interest rates and availability of financing;
vacancies, changes in market rental rates and the need to periodically repair, renovate and re-let space;
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delays in completion of development and redevelopment projects due to supply chain disruptions and labor shortages;
increased costs to maintain, renovate and develop our properties related to inflation;
changes in space utilization by our clients due to technology, economic conditions and business culture;
increased operating costs, including insurance expense, utilities, real estate taxes, state and local taxes and heightened security costs;
civil disturbances, earthquakes and other natural disasters or terrorist acts or acts of war which may result in uninsured or underinsured losses or decrease the desirability to our clients in impacted locations;
significant expenditures associated with each investment, such as debt service payments, real estate taxes (including reassessments and changes in tax laws), insurance and maintenance costs which are generally not reduced when circumstances cause a reduction in revenues from a property;
declines in the financial condition of our clients and our ability to collect rents from our clients; and
decreases in the underlying value of our real estate.
We face potential adverse effects from major clients’ bankruptcies or insolvencies.
The bankruptcy or insolvency of a major client may adversely affect the income produced by our properties. Our clients could file for bankruptcy protection or become insolvent in the future. We cannot evict a client solely because of its bankruptcy. On the other hand, a bankrupt client may reject and terminate its lease with us. In such case, our claim against the bankrupt client for unpaid and future rent would be subject to a statutory cap that might be substantially less than the remaining rent actually owed under the lease, and, even so, our claim for unpaid rent would likely not be paid in full. This shortfall could adversely affect our cash flow and results of operations. On November 6, 2023, WeWork Inc. and certain of its direct and indirect subsidiaries (collectively, “WeWork”) filed voluntary petitions to commence proceedings under Chapter 11 of title 11 of the United States Code in the United States Bankruptcy Court for the District of New Jersey. As of December 31, 2023, WeWork was one of our 20 largest clients (based on our share of square footage). There can be no assurance that WeWork will not reject one or more of the four leases.
Our properties face significant competition.
We face significant competition from developers, owners and managers of office, life sciences and residential properties and other commercial real estate, including sublease space available from our clients. Substantially all of our properties face competition from similar properties in the same market. This competition may affect our ability to attract and retain clients and may reduce the rents we are able to charge. These competing properties may have vacancy rates higher than our properties, which may result in their owners being willing to lease available space at lower rates than the space in our properties.
We face potential difficulties or delays renewing leases or re-leasing space.
We derive most of our income from rent received from our clients. If a client experiences a downturn in its business or other types of financial distress, it may be unable to make timely rental payments. Also, when our clients decide not to renew their leases, renew for less space or terminate early, we may not be able to re-let the space or there could be a substantial delay in re-letting the space. Even if clients decide to renew or lease new space, the terms of renewals or new leases, including the cost of required renovations or concessions to clients, may be less favorable to us than current lease terms. As a result, our cash flow could decrease and our ability to make distributions to our securityholders could be adversely affected.
Our actual costs to develop properties may exceed our budgeted costs.
We intend to continue to develop and substantially renovate office, life sciences, retail and residential properties. Our current and future development and construction activities may be exposed to the following risks: 
we may be unable to proceed with the development of properties because we cannot obtain financing on favorable terms or at all;
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we may incur construction costs for a development project that exceed our original estimates due to increased materials, labor, leasing or other costs, increases in interest rates, or supply chain disruptions, any of which could make completion of the project less profitable because market rents may not increase sufficiently to compensate for the increase in construction costs;