What changed in Alexandria Real Estate Equities's 10-K — 2023 vs 2024

This asset base includes 42.0 million RSF of operating properties, 5.5 million RSF of Class A/A+ properties undergoing construction and one near-term project expected to commence construction in the next two years, 2.1 million RSF of priority anticipated development and redevelopment projects, and 23.9 million SF of future development projects.

A key element of our strategy is our unique focus on Class A/A+ properties located in collaborative life science, agtech, and advanced technology mega campuses in AAA innovation clusters. These key campus locations are generally characterized by high barriers to entry for new landlords, high barriers to exit for tenants, and a limited supply of available space.

They generally represent highly desirable locations for tenancy by life science, agtech, and technology entities because of their close proximity to concentrations of specialized skills, knowledge, institutions, and related businesses.

Our tenant base is broad and diverse within the life science, agtech, and technology industries and reflects our focus on regional, national, and international tenants with substantial financial and operational resources. For a more detailed description of our properties and tenants, refer to “Item 2. Properties” in this annual report on Form 10-K.

We have an experienced Board of Directors (the “Board”) and are led by an executive and senior management team with extensive experience in the real estate, life science, agtech, and technology industries. Acquisitions We seek to identify and acquire high-quality properties in our cluster markets. Critical evaluation of prospective property acquisitions is an essential component of our acquisition strategy.

When evaluating acquisition opportunities, we assess a full range of matters relating to the prospective property or properties, including: • Proximity to centers of innovation and technological advances; • Location of the property and our strategy in the relevant market, including our mega campus strategy; • Quality of existing and prospective tenants; • Condition and capacity of the building infrastructure; • Physical condition of the structure and common area improvements; • Quality and generic characteristics of the improvements; • Opportunities available for leasing vacant space and for re-tenanting or renewing occupied space; • Availability of and/or ability to add appropriate tenant amenities; • Availability of land for future ground-up development of new space; • Opportunities to generate higher rent through redevelopment of existing space; • The property’s unlevered yields; • Potential impacts of climate change and extreme weather conditions; and • Our ability to increase the property’s long-term financial returns.

Development, redevelopment, and pre-construction A key component of our business model is our disciplined allocation of capital to the development and redevelopment of new Class A/A+ properties, and property enhancements identified during the underwriting of certain acquired properties, located in collaborative life science, agtech, and advanced technology mega campuses in AAA innovation clusters.

These projects are generally focused on providing high-quality, generic, and reusable spaces that meet the real estate requirements of a wide range of tenants. Upon completion, each value-creation project is expected to generate increases in rental income, net operating income, and cash flows.

Our development and redevelopment projects are generally in locations that are highly desirable to high-quality entities, which we believe results in higher occupancy levels, longer lease terms, higher rental income, higher returns, and greater long-term asset value. Development projects generally consist of the ground-up development of generic and reusable laboratory facilities.

Redevelopment projects consist of the permanent change in use of acquired office, warehouse, or shell space into laboratory, agtech, or advanced technology space.

We generally will not commence new development projects for aboveground construction of new Class A/A+ laboratory, agtech, and advanced technology space without first securing significant pre-leasing for such space, except when there is solid market demand for high-quality Class A/A+ properties. Pre-construction activities include entitlements, permitting, design, site work, and other activities preceding commencement of construction of aboveground building improvements.

The advancement of pre-construction efforts is focused on reducing the time required to deliver projects to prospective tenants. These critical activities add significant value for future ground-up development and are required for the vertical construction of buildings. Ultimately, these projects will provide high-quality facilities and are expected to generate significant revenue and cash flows.

Another key component of our business model is our value-creation redevelopment of acquired office, warehouse, or shell space into high-quality, generic, and reusable laboratory space that can be leased at higher rental rates.

Our redevelopment strategy generally includes significant pre-leasing of projects prior to the commencement of redevelopment. 2 Non-real estate investments We also hold strategic investments in publicly traded companies and privately held entities primarily involved in the life science, agtech, and technology industries.

We invest primarily in highly innovative entities whose focus on the development of therapies and products that advance human health and transform patients’ lives is aligned with Alexandria’s purpose of making a positive and meaningful impact on the health, safety, and well-being of the global community. Our status as a REIT limits our ability to make such non-real estate investments.

Therefore, we conduct, and will continue to conduct, our non-real estate investment activities in a manner that complies with REIT requirements.

Balance sheet and financial strategy We seek to maximize balance sheet liquidity and flexibility, cash flows, and cash available for distribution to our stockholders through the ownership, operation, management, and selective acquisition, development, and redevelopment of new Class A/A+ properties located in collaborative life science, agtech, and advanced technology mega campuses in AAA innovation clusters, as well as the prudent management of our balance sheet.

In particular, we seek to maximize balance sheet liquidity and flexibility, cash flows, and cash available for distribution to our stockholders by: • Maintaining access to diverse sources of capital, which include, among others, net cash flows from operating activities after dividends, incremental leverage-neutral debt supported by growth in EBITDA, strategic value harvesting and asset recycling through real estate dispositions and sales of partial interests, non-real estate investment sales, sales of equity, and joint venture capital; • Maintaining significant liquidity through borrowing capacity under our unsecured senior line of credit and commercial paper program, secured construction loans, marketable securities, issuances of forward equity contracts from time to time, and cash, cash equivalents, and restricted cash; • Continuing to improve our credit profile; • Minimizing the amount of debt maturing in a single year; • Maintaining commitment to long-term capital to fund growth; • Maintaining low to modest leverage; • Minimizing variable interest rate risk; • Generating high-quality, strong, and increasing operating cash flows; • Selectively selling real estate assets, including land parcels, non-core and “core-like” operating assets, and sales of partial interests, and reinvesting the proceeds into our highly leased value-creation development and redevelopment projects; • Allocating capital to Class A/A+ properties located in collaborative life science, agtech, and advanced technology mega campuses in AAA innovation clusters; • Maintaining geographic diversity in intellectual centers of innovation; • Selectively acquiring high-quality life science, agtech, and advanced technology space in our target innovation cluster submarkets at prices that enable us to realize attractive returns; • Selectively developing properties in our target innovation cluster submarkets; • Selectively redeveloping acquired office, warehouse, or shell space, or newly acquired properties, into high-quality, generic, and reusable laboratory space that can be leased at higher rental rates in our target innovation cluster submarkets; • Renewing existing tenant space at higher rental rates to the extent possible; • Minimizing tenant improvement costs; • Improving investment returns through the leasing of vacant space and the replacing of existing tenants with new tenants at higher rental rates; • Executing leases with high-quality tenants and proactively monitoring tenant health; • Maintaining solid occupancy while attaining high rental rates; • Realizing contractual rental rate escalations; and • Implementing effective cost control measures, including negotiating pass-through provisions in tenant leases for operating expenses and certain capital expenditures. 3 Competition In general, other laboratory and technology properties are located in close proximity to our properties.

The amount of rentable space available in any market could have a material effect on our ability to rent space and on the rental rates we can attain for our properties. In addition, we compete for investment opportunities with other REITs, insurance companies, pension and investment funds, private equity entities, partnerships, developers, investment companies, owners/occupants, and foreign investors.

Many of these entities have substantially greater financial resources than we do and may be able to invest more than we can or accept more risk than we are willing to accept. These entities may be less sensitive to risks with respect to the creditworthiness of a tenant or the overall expected returns from real estate investments.

In addition, as a result of their financial resources, our competitors may offer more free rent concessions, lower rental rates, or higher tenant improvement allowances in order to attract tenants. These leasing incentives could hinder our ability to maintain or raise rents and attract or retain tenants.

Competition may also reduce the number of suitable investment opportunities available to us or may increase the bargaining power of property owners seeking to sell. Competition in acquiring existing properties and land, both from institutional capital sources and from other REITs, has been very strong over the past several years; however, we believe we have differentiated ourselves from our competitors.

Alexandria pioneered the life science real estate niche with our founding in 1994, and today is the preeminent and longest-tenured owner, operator, and developer of life science, agtech, and advanced technology mega campuses in AAA innovation cluster locations. We continue to maintain and cultivate many of the most important and strategic relationships in the life science, agtech, and technology industries.

Financial information about our reportable segment Refer to Note 2 – “Summary of significant accounting policies” to our consolidated financial statements under Item 15 in this annual report on Form 10-K for information about our one reportable segment. Regulation General Properties in our markets are subject to various laws, ordinances, and regulations, including regulations relating to common areas.

We believe we have the necessary permits and approvals to operate each of our properties. Americans with Disabilities Act Our properties must comply with Title III of the Americans with Disabilities Act of 1990 (“ADA”) to the extent that such properties are “public accommodations” as defined by the ADA.

The ADA may require removal of structural barriers to permit access by persons with disabilities in certain public areas of our properties where such removal is readily achievable. We believe that our properties are in substantial compliance with the ADA and that we will not be required to incur substantial capital expenditures to address the requirements of the ADA.

However, noncompliance with the ADA could result in the imposition of fines or an award of damages to private litigants. The obligation to make readily achievable accommodations is an ongoing one, and we will continue to assess our properties and make alterations as appropriate in this respect.

Environmental matters Under various environmental protection laws, a current or previous owner or operator of real estate may be liable for contamination resulting from the presence or discharge of hazardous or toxic substances at that property and may be required to investigate and remediate contamination located on or emanating from that property.

Such laws often impose liability without regard to whether the owner or operator knew of, or was responsible for, the presence of the contaminants, and the liability may be joint and several. Previous owners may have used some of our properties for industrial and other purposes, so those properties may contain some level of environmental contamination.

The presence of contamination or the failure to remediate contamination at our properties may expose us to third-party liability or may materially adversely affect our ability to sell, lease, or develop the real estate or to borrow capital using the real estate as collateral.

State regulations, such as California’s Connelly Act and Proposition 65, among others, require certain building owners and operators to disclose information on the presence of asbestos or other harmful substances. Some of our properties may have asbestos-containing building materials.

Environmental laws require that asbestos-containing building materials be properly managed and maintained and may impose fines and penalties on building owners or operators for failure to comply with these requirements. These laws may also allow third parties to seek recovery from owners or operators for personal injury associated with exposure to asbestos-containing building materials.

In addition, some of our tenants handle hazardous substances and wastes as part of their routine operations at our properties. Environmental laws and regulations subject our tenants, and potentially us, to liability resulting from such activities. Environmental liabilities could also affect a tenant’s ability to make rental payments to us.

We require our tenants to comply with these environmental laws and regulations and to indemnify us against any related liabilities. 4 Independent environmental consultants have conducted Phase I or similar environmental site assessments on the properties in our portfolio.

Site assessments are intended to discover and evaluate information regarding the environmental condition of the surveyed property and surrounding properties and do not generally include soil samplings, subsurface investigations, or an asbestos survey.

To date, these assessments have not revealed any material environmental liability that we believe would have a material adverse effect on our business, assets, or results of operations, and ongoing expenditures to comply with existing environmental regulations are not expected to be material.

Nevertheless, it is possible that the assessments on our properties have not revealed all environmental conditions, liabilities, or compliance concerns that may have arisen after the review was completed or may arise in the future; and future laws, ordinances, or regulations may also impose additional material environmental liabilities.

Insurance With respect to our properties, we carry commercial general liability insurance, and all-risk property insurance, including business interruption and loss of rental income coverage. We select policy specifications and insured limits that we believe to be appropriate given the relative risk of loss and the cost of the coverage.

In addition, we have obtained earthquake insurance for certain properties located in the vicinity of known active earthquake zones in an amount and with deductibles we believe are commercially reasonable. We also carry environmental insurance and title insurance policies on our properties.

We generally obtain title insurance policies when we acquire a property, with each policy covering an amount equal to the initial purchase price of each property. Accordingly, any of our title insurance policies may be in an amount less than the current value of the related property.

Additional information about risk factors that may affect us is included in “Item 1A. Risk factors” in this annual report on Form 10-K.

Available information Copies of our annual reports on Form 10-K, quarterly reports on Form 10-Q, and current reports on Form 8-K, including any amendments to the foregoing reports, are available, free of charge, through our corporate website at www.are.com as soon as is reasonably practicable after such material is electronically filed with, or furnished to, the SEC.

The current charters of our Board of Directors’ Audit, Compensation, and Nominating & Governance Committees, along with our Corporate Governance Guidelines and Business Integrity Policy and Procedures for Reporting Non-Compliance (the “Business Integrity Policy”), are also available on our corporate website.

Additionally, any amendments to, and waivers of, our Business Integrity Policy that apply to our Chief Executive Officer or our Chief Financial Officer will be available free of charge on our corporate website in accordance with applicable SEC and NYSE requirements.

Written requests should be sent to Alexandria Real Estate Equities, Inc., 26 North Euclid Avenue, Pasadena, California 91101, Attention: Investor Relations. The public may also download these materials from the SEC’s website at www.sec.gov. 5 Human capital As of December 31, 2023, we had 568 employees. We place a significant focus on building loyalty and trusted relationships with our employees.

We have a Business Integrity Policy that applies to all of our employees, and its receipt and review by each employee is documented and verified annually. To promote an exceptional corporate culture, Alexandria continuously monitors employee satisfaction, seeks employee feedback, and proactively enhances our employee offerings.

We participate in annual performance reviews with our employees and conduct formal employee surveys, and our talent management team holds regular meetings with employees to continuously gather feedback and improve the employee experience.

The positive employee experience is evidenced by our low voluntary and total turnover rates averaging 4.1% and 8.3%, respectively, over the last five years, from 2019 to 2023, which are substantially lower than the average voluntary and total turnover rates of 14.0% and 19.0%, respectively, as reported for the REIT industry in the 2023 Nareit Compensation & Benefits Survey (data for 2022).

We recognize that the fundamental strength of Alexandria results from the contributions of each and every team member within the organization and that our future growth is dependent upon the same.

Alexandria devotes extraordinary efforts to hiring, developing, and retaining our talented employees, and we understand firsthand that the health, happiness, and well-being of our best-in-class team are key factors to the success of our employees and that of the Company. We have an exceptional track record of identifying highly qualified candidates for promotion from within the Company.

Alexandria’s executive and senior management teams, represented by our senior vice presidents and above, consist of 60 individuals, averaging 23 years of real estate experience, including 13 years with Alexandria. Moreover, our executive management team alone averages 18 years of experience with the Company.

Alexandria’s executive and senior management teams have unique experience and expertise in creating, owning, and operating highly dynamic and collaborative mega campuses in key life science, agtech, and advanced technology cluster locations. These teams include regional market directors with leading reputations and longstanding relationships within the life science, agtech, and technology communities in their respective innovation clusters.

We believe that our expertise, experience, reputation, and key relationships in the real estate, life science, agtech, and technology industries provide Alexandria with significant competitive advantages in attracting new business opportunities. Building a diverse board of directors and inclusive workforce Our Corporate Governance Guidelines highlight our Board of Directors’ focus on diversity at the board level.

The guidelines explicitly state the Board of Directors’ commitment to considering qualified women and minority director candidates, as well as its policy of requesting an initial list of diverse candidates from any search firm it retains.

We strive to create an open and respectful environment where our employees can actively contribute, have access to opportunities and resources, and realize their full potential.

As an equal opportunity employer, we have an Equal Employment Opportunity Policy and a Diversity, Equal Employment Opportunity, and Fair Labor Policy that emphasizes inclusion through hiring and compensation practices and considers a pool of diverse candidates for open positions and internal advancement opportunities.

Furthermore, as a federal government contractor, Alexandria maintains affirmative action plans, which set forth the policies, practices, and procedures to which the Company is committed in order to ensure that our policies of nondiscrimination and affirmative action are followed for qualified females, minorities, individuals with disabilities, and protected veterans.

To address issues related to pay discrimination, the Company has a ban on any and all inquiries into an applicant’s salary history, and we incorporate fair pay reviews into every employment compensation decision. To reinforce our corporate culture of respect, diversity, and inclusion, we provide anti-harassment training annually.

Providing exceptional benefits to support our employees’ medical and financial health and well-being We provide a comprehensive benefits package intended to meet and/or exceed the needs of our employees and their families.

Our company-sponsored suite of benefits covers 100% of the premiums for our employees and their dependents and includes, but is not limited to, a high-coverage, low-deductible preferred provider organization (“PPO”) medical plan, a 24/7 telehealth and concierge medical care services program, PPO dental and orthodontia coverage, a generous vision plan, comprehensive prescription drug plan, infertility and family planning benefits, short-term and long-term disability benefits, and life and accidental death and dismemberment coverage.

These benefits support the health of our employees and their families, their overall well-being, and their future plans, and also reward their operational excellence.

In addition, we have prioritized our employees’ total well-being with additional benefits that focus on their emotional, mental, physical, financial, and social health including: • 100% company-paid therapy and life coaching to help our employees and their eligible dependents prioritize their mental health and provide timely access to professional help; • Additional company-paid holidays and paid time off to encourage employees to rest and recharge; • 24/7 telehealth and medical care ; 6 • Expert-led internal webinar series leveraging our world-class life science network to educate and inform our employees on relevant and engaging subjects; • Wellness reimbursement benefit for fitness, self-defense, mindfulness applications, subscriptions, and classes, and home exercise equipment to encourage our employees to stay mentally and physically fit; • Enhanced social connectedness through Alexandria’s Operation CARE program for giving to, fundraising for, and volunteering at any eligible non-profit organization(s) of an employee’s choosing, including: • Paid volunteer time off of up to16 hours per calendar year, • Matching gifts of up to $5,000 per calendar year, • Volunteer rewards of up to $10,000 per calendar year donated by Alexandria based on time volunteered ($2,500 donated per 25 hours); • Alexandria Lifeline ™ – Alexandria’s unparalleled network in the life science community affords us access to deep medical expertise.

Alexandria Lifeline makes this expertise available to our employees and their immediate family members who are suffering from a serious illness or injury and would benefit from specialized medical care. Investing in professional development and training Alexandria champions our people as our greatest asset. To attract and retain the best talent, we provide meaningful opportunities for growth and development.

We offer a variety of learning opportunities, including custom, cohort-based development programs that leverage social learning, instructor-led trainings, on-demand trainings and resources, and a highly utilized mentoring program. Development programs and trainings include topics such as leadership development, project management, business writing, change management, interviewing, presentations, productivity, effective one-on-ones, goal setting, delegation, communication, and feedback.

Our mentoring program enables employees to partner with senior leaders throughout the organization for support and career guidance. To further customize development, we partner with key functional leaders to design and implement learning programs for specific functional teams and curated learning cohorts. Lastly, our executive coaching program supports high-potential leaders in their career progression.

To continuously monitor and improve employee performance and engagement, we use employee engagement surveys, the most recent of which was conducted in 2022 and yielded an employee participation rate of 91.4%. 7 (1) As of December 31, 2023, unless stated otherwise.

We determine race and gender based on our employees' self-identification or other information compiled to meet requirements of the U.S. government. (2) Minorities are defined to include individuals of Asian, Black/African American, Hispanic/Latino, Native American, Pacific Islander, or multiracial background. (3) Managers and above include individuals who lead others and/or oversee projects.

(4) Represents a five-year average from 2019 to 2023. 8

ITEM 1A. RISK FACTORS Overview The following risk factors may adversely affect our overall business, financial condition, results of operations, and cash flows; our ability to make distributions to our stockholders; our access to capital; or the market price of our common stock, as further described in each risk factor below.

In addition to the information set forth in this annual report on Form 10-K, one should carefully review and consider the information contained in our other reports and periodic filings that we make with the SEC.

Those risk factors could materially affect our overall business, financial condition, results of operations, and cash flows; our ability to make distributions to our stockholders; our access to capital; or the market price of our common stock. The risks that we describe in our public filings are not the only risks that we face.

Additional risks and uncertainties not presently known to us, or that we currently consider immaterial, also may materially adversely affect our business, financial condition, and results of operations. Additional information regarding forward-looking statements is included in the beginning of Part I in this annual report on Form 10-K. Risk factors summary An investment in our securities involves various risks.

Such risks, including those set forth in the summary of material risks in this Item 1A, should be carefully considered before purchasing our securities.

Risks related to operating factors • We may be unable to identify and complete acquisitions, investments, or development or redevelopment projects or to successfully and profitably operate properties. • We could default on our ground leases or be unable to renew or re-lease our land or space on favorable terms or at all.

Our tenants may also be unable to pay us rent. • The cost of maintaining and improving the quality of our properties may be higher than anticipated, and we may be unable to pass any increased operating costs through to our tenants, which can result in reduced cash flows and profitability. • We could be held liable for environmental damages resulting from our tenants’ use of hazardous materials, or from harmful mold, poor air quality, or other defects from our properties, or we could face increased costs in complying with other environmental laws. • The loss of services of any of our senior officers or key employees and increased competition for skilled personnel could adversely affect us and/or increase our labor costs. • We rely on a limited number of vendors to provide utilities and other services at our properties, and disruption in such services may have an adverse effect on our operations and financial condition. • Our insurance policies may not adequately cover all of our potential losses, or we may incur costs due to the financial condition of our insurance carriers. • We may change business policies without stockholder approval. • Failure to maintain effective internal control over financial reporting could have a material adverse effect on our business. • If we failed to qualify as a REIT, we would be taxed at corporate rates and would not be able to take certain deductions when computing our taxable income. • We may not be able to raise sufficient capital to fund our operations due to adverse changes in our credit ratings, our inability to refinance our existing debt or issue new debt, or our inability to sell existing real estate and non-real estate assets timely or at optimal prices. • We may invest or spend the net proceeds from our equity or debt offerings in ways with which our investors may not agree and in ways that may not earn a profit. • Our debt service obligations may restrict our ability to engage in some business activities or cause other adverse effects on our business. • We face risks and liabilities associated with our investments (including those in connection with short-term liquid investments) and the companies in which we invest (including properties owned through partnerships, limited liability companies, and joint ventures, as well as through our non-real estate venture investment portfolio), which expose us to risks similar to those of our tenant base and additional risks inherent in venture capital investing.

We may be limited in our ability to diversify our investments.

Risks related to market and industry factors • There are limits on ownership of our stock under which a stockholder may lose beneficial ownership of its shares, as well as certain provisions of our charter and bylaws that may delay or prevent transactions that otherwise may be desirable to our stockholders. • Possible future sales of shares of our common stock could adversely affect its market price. • We are dependent on the health of the life science, agtech, and technology industries, and changes within these industries, increased competition, or the inability of our tenants and non-real estate equity investments within these industries to obtain funding for research, development, and other operations may adversely impact their ability to make rental payments to us or adversely impact their value. 9 • Market disruption and volatility, poor economic conditions in the capital markets and global economy, including in connection with a widespread pandemic or outbreak of a highly infectious or contagious disease, and tight labor markets could adversely affect the value of the companies in which we hold equity investments or the ability of tenants and the companies in which we invest to continue operations, raise additional capital, or access capital from venture capital investors or financial institutions on favorable terms or at all.

Risks related to government and global factors • Actions, policy, or key leadership changes in government agencies, or changes to laws or regulations, including those related to tax, accounting, debt, derivatives, government spending, or funding (including those related to the FDA, the National Institutes of Health (the “NIH”), the SEC, and other agencies), and drug and healthcare pricing, costs, and programs could have a significant negative impact on the overall economy, our tenants and companies in which we invest, and our business. • Partial or complete government shutdown resulting in temporary closures of agencies could adversely affect our tenants (some of which are also government agencies) and the companies in which we invest, including delays in the commercialization of such companies’ products, decreased funding of research and development, or delays surrounding approval of budget proposals. • The outbreak of any highly infectious or contagious disease could adversely impact our financial condition and results of operations, and/or that of our tenants and non-real estate investments.

Risks related to general and other factors • Social, political, and economic instability, unrest, significant changes, and other circumstances beyond our control, including circumstances related to changes in the U.S. political landscape, could adversely affect our business operations. • Seasonal weather conditions, climate change and severe weather, changes in the availability of transportation or labor, and other related factors may affect our ability to conduct business, the products and services of our tenants, or the availability of such products and services of our tenants and the companies in which we invest. • We may be unable to meet our sustainability goals. • Changes in privacy and information security laws, regulations, policies, and contractual obligations related to data privacy and security, or our failure to comply with such requirements, could subject us to fines or penalties or increase our cost of doing business, compliance risks, and potential liability and otherwise adversely affect our business or results of operations. • System failures or security incidents through cyberattacks, intrusions, or other methods could disrupt our information technology networks, enterprise applications, and related systems, cause a loss of assets or data, give rise to remediation or other expenses, expose us to liability under federal and state laws, and subject us to litigation and investigations, which could result in substantial reputational damage and adversely affect our business and financial condition. • The enactment of legislation, including the Inflation Reduction Act of 2022, may adversely impact our financial condition and results of operations.

However, if we are unable to effectively manage the impact of these and other risks, our ability to meet our investment objectives may be substantially impaired and any of the foregoing risks could materially adversely affect our financial condition, results of operations, and cash flows, our ability to make distributions to our stockholders, or the market price of our common stock. 10 Operating factors We may be unable to identify and complete acquisitions and successfully operate acquired properties.

We continually evaluate the market of available properties and may acquire properties when opportunities exist.

Our ability to acquire properties on favorable terms and successfully operate them may be exposed to significant risks, including, but not limited to, the following: • We may be unable to acquire a desired property because of competition from other real estate investors with significant capital, including both publicly traded REITs and institutional funds. • Even if we are able to acquire a desired property, competition from other potential acquirers may significantly increase the purchase price or result in other less favorable terms. • Even if we enter into agreements for the acquisition of properties, these agreements are subject to customary conditions to closing, including completion of due diligence investigations to our satisfaction. • We may be unable to complete an acquisition because we cannot obtain debt and/or equity financing on favorable terms or at all. • We may spend more than budgeted amounts to make necessary improvements or renovations to acquired properties. • We may be unable to quickly and efficiently integrate new acquisitions, particularly acquisitions of operating properties or portfolios of properties, into our existing operations. • Acquired properties may be subject to tax reassessment, which may result in higher-than-expected property tax payments. • Market conditions may result in higher-than-expected vacancy rates and lower-than-expected rental rates. • We may acquire properties subject to liabilities and without any recourse, or with only limited recourse, with respect to unknown liabilities, such as liabilities for the remediation of undisclosed environmental contamination; claims by tenants, vendors, or other persons dealing with the former owners of the properties; and claims for indemnification by general partners, directors, officers, and others indemnified by the former owners of the properties.

The realization of any of the above risks could significantly and adversely affect our ability to meet our financial expectations, our financial condition, results of operations, and cash flows, our ability to make distributions to our stockholders, the market price of our common stock, and our ability to satisfy our debt service obligations.

We may suffer economic harm as a result of making unsuccessful acquisitions in new markets. We may pursue selective acquisitions of properties in markets where we have not previously owned properties.

These acquisitions may entail risks in addition to those we face in other acquisitions where we are familiar with the markets, such as the risk of not correctly anticipating conditions or trends in a new market and therefore not being able to generate profit from the acquired property.

If this occurs, it could adversely affect our financial condition, results of operations, and cash flows, our ability to make distributions to our stockholders, our ability to satisfy our debt service obligations, and the market price of our common stock. The acquisition or development of new properties may give rise to difficulties in predicting revenue potential.

We may continue to acquire additional properties and/or land and may seek to develop our existing land holdings strategically as warranted by market conditions. These acquisitions and developments could fail to perform in accordance with expectations.

If we fail to accurately estimate occupancy levels, rental rates, lease commencement dates, operating costs, or costs of improvements to bring an acquired property or a development property up to the standards established for our intended market position, the performance of the property may be below expectations.

Acquired properties may have characteristics or deficiencies affecting their valuation or revenue potential that we have not yet discovered. We cannot assure our stockholders that the performance of properties acquired or developed by us will increase or be maintained under our management. We may fail to achieve the financial results expected from development or redevelopment projects.

There are significant risks associated with development and redevelopment projects, including, but not limited to, the following possibilities: • We may not complete development or redevelopment projects on schedule or within budgeted amounts. • We may be unable to lease development or redevelopment projects on schedule or within projected amounts. • We may encounter project delays or cancellations due to unavailability of necessary labor and construction materials. • We may expend funds on, and devote management’s time to, development and redevelopment projects that we may not complete. • We may abandon development or redevelopment projects after we begin to explore them, and as a result, we may lose deposits or fail to recover costs already incurred. • Market and economic conditions may deteriorate, which can result in lower-than-expected rental rates. 11 • We may face higher operating costs than we anticipated for development or redevelopment projects, including insurance premiums, utilities, security, real estate taxes, and costs of complying with changes in government regulations or increases in tariffs. • We may face higher requirements for capital improvements than we anticipated for development or redevelopment projects, particularly in older structures. • We may be unable to proceed with development or redevelopment projects because we cannot obtain debt and/or equity financing on favorable terms or at all. • We may fail to retain tenants that have pre-leased our development or redevelopment projects if we do not complete the construction of these properties in a timely manner or to the tenants’ specifications. • Tenants that have pre-leased our development or redevelopment projects may file for bankruptcy or become insolvent, or otherwise elect to terminate their lease prior to delivery, which may adversely affect the income produced by, and the value of, our properties or require us to change the scope of the project, which may potentially result in higher construction costs, significant project delays, or lower financial returns. • We may encounter delays, refusals, unforeseen cost increases, and other impairments resulting from third-party litigation, natural disasters, or severe weather conditions. • We may encounter delays or refusals in obtaining all necessary zoning, land use, building, occupancy, and other required government permits and authorizations. • We may be unable to proceed with our development or redevelopment projects as anticipated due to changing zoning, land use, building, occupancy, or other government codes or regulations. • Development or redevelopment projects may have defects we do not discover through our inspection processes, including latent defects that may not reveal themselves until many years after we put a property in service.

The realization of any of the above risks could significantly and adversely affect our ability to meet our financial expectations, our financial condition, results of operations, and cash flows, our ability to make distributions to our stockholders, the market price of our common stock, and our ability to satisfy our debt service obligations.

We may face increased risks and costs associated with volatility in commodity and labor prices or as a result of supply chain or procurement disruptions, which may adversely affect the status of and returns on our construction projects.

The price of commodities and skilled labor for our construction projects may increase unpredictably due to external factors, including, but not limited to, performance of third-party suppliers and contractors; overall market supply and demand; inflationary pricing; government regulation; international trade; and changes in general business, economic, or political conditions.

As a result, the costs of raw construction materials and skilled labor required for the completion of our development and redevelopment projects may fluctuate significantly from time to time. We rely on a number of third-party suppliers and contractors to supply raw materials and skilled labor for our construction projects.

We believe we have favorable relationships with our suppliers and contractors. We have not encountered significant difficulty collaborating with our suppliers and contractors and obtaining materials and skilled labor, nor experienced significant delays due to disputes, work stoppages, or contractors’ misconduct or failure to perform.

While we do not rely on any single supplier or vendor for the majority of our materials and skilled labor, we may experience difficulties obtaining necessary materials from suppliers or vendors whose supply chains might become impacted by economic or political changes, or difficulties obtaining adequate skilled labor from third-party contractors in a tightening labor market.

It is uncertain whether we would be able to source the essential commodities, supplies, materials, and skilled labor timely or at all without incurring significant costs or delays, particularly during times of economic uncertainty resulting from events outside of our control.

We may be forced to purchase supplies and materials in larger quantities or in advance of when we would typically purchase them. This may cause us to require use of capital sooner than anticipated.

Alternatively, we may also be forced to seek new third-party suppliers or contractors, whom we have not worked with in the past, and it is uncertain whether these new suppliers will be able to adequately meet our materials or labor needs.

Our dependence on unfamiliar supply chains or relatively small supply partners may adversely affect the cost and timely completion of our construction projects. In addition, we may be unable to compete with entities that may have more favorable relationships with their suppliers and contractors or greater access to the required construction materials and skilled labor.

In addition, new climate change-related initiatives entered into by the U.S. government in collaboration with partner countries through global climate agreements may impose stricter requirements for building materials, such as lumber, steel, and concrete, which could significantly increase our construction costs if the manufacturers and suppliers of our materials are burdened with expensive cap-and-trade or similar regulations or requirements, and the costs of which are passed onto customers like us.

As a result of the factors discussed above, we may be unable to complete our development or redevelopment projects timely and/or within our budget, which may affect our ability to lease space to potential tenants and adversely affect our business, financial condition, and results of operations. 12 If we fail to identify and develop relationships with a sufficient number of qualified suppliers and contractors, the quality and status of our construction projects may be adversely affected.

We believe we have favorable relationships with our existing suppliers and contractors, and we generally have not encountered difficulty collaborating with and obtaining materials and skilled labor, nor experienced significant delays or increases in overall project costs due to disputes, work stoppages, or contractors’ misconduct or failure to perform.

However, it is possible we may experience these events in the future, or our existing suppliers and contractors may encounter supply chain disruptions from time to time that hinder their ability to supply necessary materials and labor to us. As a result, we may be forced to seek new resources for our construction needs.

We may become reliant on unfamiliar supply chains or relatively small supply partners, which may cause uncertainty in the quality, cost, and timely completion of our construction projects.

Our ability to continue to identify and develop relationships with a sufficient network of qualified suppliers who can adequately meet our construction timing and quality standards can be a significant challenge, particularly in the event of global supply chain disruptions.

If we fail to identify and develop relationships with a sufficient number of suppliers and contractors who can appropriately address our construction needs, we may experience disruptions in our suppliers’ logistics or supply chain networks or information technology systems, and other factors beyond our or our suppliers’ control.

ITEM 2. PROPERTIES General As of December 31, 2023, we had 411 properties in North America consisting of approximately 47.2 million RSF of operating properties and new Class A/A+ development and redevelopment properties under construction, including 68 properties that are held by consolidated real estate joint ventures and four properties that are held by unconsolidated real estate joint ventures.

The occupancy percentage of our operating properties in North America was 94.6% as of December 31, 2023. The exteriors of our properties typically resemble traditional office properties, but the interior infrastructures are designed to accommodate the needs of life science, agtech, and technology tenants. These improvements typically are generic rather than specific to a particular tenant.

As a result, we believe that the improvements have long-term value and utility and are usable by a wide range of tenants.

Improvements to our properties typically include: • Reinforced concrete floors; • Upgraded roof loading capacity; • Increased floor-to-ceiling heights; • Heavy-duty HVAC systems; • Enhanced environmental control technology; • Significantly upgraded electrical, gas, and plumbing infrastructure; and • Laboratory benches.

As of December 31, 2023, we held a fee simple interest in each of our properties, with the exception of 36 properties in North America subject to ground leasehold interests, which accounted for approximately 9% of our total number of properties.

During the year ended December 31, 2023, as a percentage of net operating income our ground lease rental expense aggregated 1.5%. Refer to our consolidated financial statements and notes thereto in “Item 15. Exhibits and financial statement schedules” in this annual report on Form 10-K for further discussion.

As of December 31, 2023, we had over 1,000 leases with a total of approximately 800 tenants, and 198, or 48%, of our 411 properties were single-tenant properties. Leases in our multi-tenant buildings typically have initial terms of 4 to 11 years, while leases in our single-tenant buildings typically have initial terms of 11 to 21 years.

Additionally, as of December 31, 2023: • Investment-grade or publicly traded large cap tenants represented 52% of our total annual rental revenue; • Approximately 96% of our leases (on an annual rental revenue basis) contained effective annual rent escalations approximating 3% that were either fixed or indexed based on a consumer price index or other index; • Approximately 94% of our leases (on an annual rental revenue basis) were triple net leases, which require tenants to pay substantially all real estate taxes, insurance, utilities, repairs and maintenance, common area expenses, and other operating expenses (including increases thereto) in addition to base rent; and • Approximately 93% of our leases (on an annual rental revenue basis) provided for the recapture of capital expenditures (such as HVAC maintenance and/or replacement, roof replacement, and parking lot resurfacing) that we believe would typically be borne by the landlord in traditional office leases.

Our leases also typically give us the right to review and approve tenant alterations to the property. Generally, tenant-installed improvements to the properties are reusable generic improvements and remain our property after termination of the lease at our election.

However, we are permitted under the terms of most of our leases to require that the tenant, at its expense, remove certain non-generic improvements and restore the premises to their original condition. Refer to the definitions of “Annual rental revenue” and “Operating statistics” in the “Non-GAAP measures and definitions” section under “Item 7.

Management’s discussion and analysis of financial condition and results of operations” in this annual report on Form 10-K for a description of the basis used to compute the aforementioned measures. 53 Locations of properties The locations of our properties are diversified among a number of Class A/A+ assets strategically clustered in life science, agtech, and advanced technology mega campuses in AAA innovation cluster markets.

The following table sets forth the total RSF, number of properties, and annual rental revenue in effect as of December 31, 2023 in each of our markets in North America (dollars in thousands, except per RSF amounts): RSF Number of Properties Annual Rental Revenue Market Operating Development Redevelopment Total % of Total Total % of Total Per RSF Greater Boston 10,836,743 975,419 1,304,051 (1) 13,116,213 28 % 72 $ 820,759 38 % $ 79.82 San Francisco Bay Area 7,906,198 498,142 300,010 8,704,350 18 67 460,272 21 66.04 New York City 922,477 — — 922,477 2 4 72,993 3 92.75 San Diego 7,831,370 1,187,796 — 9,019,166 19 90 320,460 14 43.48 Seattle 2,962,995 33,349 148,890 3,145,234 7 44 131,377 6 46.57 Maryland 3,582,494 510,601 — 4,093,095 9 51 123,780 6 36.57 Research Triangle 3,840,876 — — 3,840,876 8 39 120,982 6 32.20 Texas 1,845,159 — 73,298 1,918,457 4 15 57,591 3 32.80 Canada 898,740 — 172,936 1,071,676 2 12 17,222 1 22.01 Non-cluster/other markets 347,806 — — 347,806 1 10 15,827 1 57.96 Properties held for sale 1,049,135 — — 1,049,135 2 7 26,907 1 N/A North America 42,023,993 3,205,307 1,999,185 47,228,485 100 % 411 $ 2,168,170 100 % $ 56.08 5,204,492 (1) Primarily relates to our active redevelopment projects at 840 Winter Street and 40, 50, and 60 Sylvan Road, aggregating 716,604 RSF located in our Alexandria Center ® for Life Science – Waltham mega campus, which are 43% leased/negotiating on a combined basis.

This mega campus project is expected to capture demand in our Route 128 submarket of Greater Boston.

Summary of occupancy percentages in North America The following table sets forth the occupancy percentages for our operating properties and our operating and redevelopment properties in each of our North America markets, excluding properties held for sale, as of the following dates: Operating Properties Operating and Redevelopment Properties Market 12/31/23 12/31/22 12/31/21 12/31/23 12/31/22 12/31/21 Greater Boston 94.9 % 94.5 % 95.2 % 84.7 % 85.5 % 83.2 % San Francisco Bay Area 94.8 96.7 93.0 91.4 93.3 92.6 New York City 85.3 (1) 92.3 98.4 85.3 92.3 91.0 San Diego 94.1 95.4 93.1 94.1 95.4 91.7 Seattle 95.2 97.0 95.6 90.7 90.1 88.5 Maryland 95.6 95.8 99.8 95.6 93.3 96.0 Research Triangle 97.8 94.0 94.6 97.8 85.0 86.1 Texas 95.1 91.2 N/A 91.5 81.6 N/A Subtotal 94.9 95.1 94.9 90.7 89.9 89.1 Canada 87.1 80.8 78.6 73.0 68.2 78.6 Non-cluster/other markets 78.5 75.0 75.1 78.5 75.0 75.1 North America 94.6 % 94.8 % 94.0 % 90.2 % 89.4 % 88.5 % (1) Occupancy in our New York City market includes vacancy at our Alexandria Center ® for Life Science – Long Island City property that is 41.7% occupied as of December 31, 2023.

In addition, our mega campus at Alexandria Center ® for Life Science – New York City is 95.8% occupied as of December 31, 2023. 54 Top 20 tenants 92% of Top 20 Tenants Annual Rental Revenue Is From Investment-Grade or Publicly Traded Large Cap Tenants (1) Our properties are leased to a high-quality and diverse group of tenants, with no individual tenant accounting for more than 5.7% of our annual rental revenue in effect as of December 31, 2023.

The following table sets forth information regarding leases with our 20 largest tenants in North America based upon annual rental revenue in effect as of December 31, 2023 (dollars in thousands, except average market cap amounts): Remaining Lease Term (1) (in Years) Aggregate RSF Annual Rental Revenue (1) Percentage of Aggregate Annual Rental Revenue (1) Investment-Grade Credit Ratings Average Market Cap (1) (in billions) Tenant Moody’s S&P 1 Moderna, Inc. 13.2 1,370,536 $ 122,763 5.7 % — — $ 47.4 2 Eli Lilly and Company 9.1 1,154,917 93,815 4.3 A2 A+ $ 440.5 3 Bristol-Myers Squibb Company 6.7 852,830 66,339 3.1 A2 A+ $ 131.5 4 Roche 6.4 770,279 46,192 2.1 Aa2 AA $ 242.1 5 Takeda Pharmaceutical Company Limited 6.0 549,760 37,399 1.7 Baa2 BBB+ $ 49.0 6 Alphabet Inc. 2.9 654,423 36,809 1.7 Aa2 AA+ $ 1,509.5 7 Illumina, Inc. 6.6 890,389 36,204 1.7 Baa3 BBB $ 27.9 8 2seventy bio, Inc.

(2) 9.7 312,805 33,617 1.6 — — $ 0.4 9 Harvard University 6.0 389,233 32,494 1.5 Aaa AAA $ — 10 Novartis AG 4.6 450,563 31,196 1.4 A1 AA- $ 221.7 11 Cloud Software Group, Inc. 3.2 (3) 292,013 28,537 1.3 — — $ — 12 Uber Technologies, Inc. 58.7 (4) 1,009,188 27,750 1.3 — — $ 84.8 13 Pfizer Inc. 1.2 (5) 524,159 25,242 1.2 A1 A+ $ 208.5 14 AstraZeneca PLC 6.0 416,761 24,583 1.1 A3 A $ 212.5 15 United States Government 6.8 340,238 23,023 1.1 Aaa AA+ $ — 16 Sanofi 7.0 267,278 21,444 1.0 A1 AA $ 129.2 17 New York University 8.1 218,983 21,056 1.0 Aa2 AA- $ — 18 Massachusetts Institute of Technology 5.4 246,725 20,504 0.9 Aaa AAA $ — 19 Boston Children’s Hospital 12.8 266,857 20,066 0.9 Aa2 AA $ — 20 Merck & Co., Inc. 9.9 312,935 20,033 0.9 A1 A+ $ 274.8 Total/weighted-average 9.6 (4) 11,290,872 $ 769,066 35.5 % Annual rental revenue and RSF include 100% of each property managed by us in North America.

(1) Based on total annual rental revenue in effect as of December 31, 2023.

Refer to the definitions of “Annual rental revenue” and “Investment-grade or publicly traded large cap tenants” in the “Non-GAAP measures and definitions” section under Item 7 in this annual report on Form 10-K for our methodologies of calculating annual rental revenue from unconsolidated real estate joint ventures and average market capitalization, respectively.

(2) As of September 30, 2023, 2seventy bio, Inc. held $250.6 million of cash, cash equivalents, and marketable securities. Additionally, 90.0% of the annual rental revenue generated by 2seventy bio, Inc. is guaranteed by another public biotechnology company (a party related to 2seventy bio, Inc.). (3) Includes one lease at a recently acquired property with future development and redevelopment opportunities.

This lease with Cloud Software Group, Inc. (formerly known as TIBCO Software, Inc.) was in place when we acquired the properties.

(4) Includes (i) ground leases for land at 1455 and 1515 Third Street (two buildings aggregating 422,980 RSF) and (ii) leases at 1655 and 1725 Third Street (two buildings aggregating 586,208 RSF) in our Mission Bay submarket owned by our unconsolidated real estate joint venture in which we have an ownership interest of 10%.

Annual rental revenue is presented using 100% of the annual rental revenue from our consolidated properties and our share of annual rental revenue from our unconsolidated real estate joint ventures. Refer to footnote 1 for additional details. Excluding the ground leases, the weighted-average remaining lease term for our top 20 tenants was 7.8 years as of December 31, 2023.

(5) Primarily relates to one office building in our New York City submarket aggregating 349,947 RSF with a contractual lease expiration in the third quarter of 2024, which was classified as held for sale as of December 31, 2023. 55 Long-Duration and Stable Cash Flows From High-Quality and Diverse Tenants REIT Industry-Leading Client Base Investment-Grade or Publicly Traded Large Cap Tenants 92% 52% of ARE’s Top 20 Tenants Annual Rental Revenue (1) of ARE’s Total Annual Rental Revenue (1) Long-Duration Lease Terms 9.6 Years 7.4 Years Top 20 Tenants All Tenants Weighted-Average Remaining Term (2) Sustained Strength in Tenant Collections (3) 99.9% For the Three Months Ended December 31, 2023 99.4% January 2024 (1) Represents annual rental revenue in effect as of December 31, 2023.

Refer to the “Non-GAAP measures and definitions” section under Item 7 in this annual report on Form 10-K for additional information. (2) Based on total annual rental revenue in effect as of December 31, 2023.

(3) Represents the portion of total receivables billed for each indicated period collected through the date of this report. 56 High-Quality and Diverse Client Base in AAA Locations Solid and Well-Diversified Tenant Base Industry Annual Rental Revenue (1) per RSF Multinational Pharmaceutical $ 64.22 Public Biotechnology – Approved or Marketed Product $ 68.98 Institutional (Academic/Medical, Non-Profit, and U.S.

Government) $ 59.95 Public Biotechnology – Preclinical or Clinical Stage $ 70.25 Private Biotechnology $ 82.51 Life Science Product, Service, and Device $ 43.45 Future Change in Use (2) $ 44.38 Investment-Grade or Large Cap Tech $ 31.93 Other (3) $ 32.61 Percentage of ARE’s Annual Rental Revenue (1) Solid Historical Occupancy of 96% Over Past 10 Years (4) From Historically Strong Demand for Our Class A/A+ Properties in AAA Locations AAA Locations Occupancy Across Key Locations Percentage of ARE’s Annual Rental Revenue (1) Refer to the “Non-GAAP measures and definitions” section under Item 7 in this annual report on Form 10-K for additional information.

(1) Represents annual rental revenue in effect as of December 31, 2023. (2) Represents annual rental revenue currently generated from space that is targeted for a future change in use, including 1.1% of total annual rental revenue that is generated from covered land play projects for future development opportunities. The weighted-average remaining term of these leases is 4.0 years.

(3) Our “Other” tenants, which represent an aggregate of 3.0% of our annual rental revenue, comprise technology, professional services, finance, telecommunications, and construction/real estate companies, and (by less than 1.0% of our annual rental revenue) retail-related tenants. (4) Represents average occupancy of operating properties in North America as of each December 31 for the last 10 years.

(5) Refer to footnote 1 in the “Summary of occupancy percentages in North America” section within this Item 2 for additional details. (6) Acquired vacancy of 1.7% from properties recently acquired in 2021 and 2022 primarily represents lease-up opportunities.

Excluding acquired vacancy, occupancy of operating properties in North America was 96.3% as of December 31, 2023. 57 Property listing Mega Campuses Encompass 75% of Our Annual Rental Revenue (1) The following table provides certain information about our properties as of December 31, 2023 (dollars in thousands): Occupancy Percentage RSF Number of Properties Annual Rental Revenue Operating Operating and Redevelopment Market / Submarket / Address Operating Development Redevelopment Total Greater Boston Cambridge/Inner Suburbs Mega Campus: Alexandria Center ® at Kendall Square 2,856,043 — — 2,856,043 11 $ 266,549 99.6 % 99.6 % 50 (2) , 60 (2) , 75/125 (2) , 100 (2) , and 225 (2) Binney Street, 140 and 215 First Street, 150 Second Street, 300 Third Street (2) , 11 Hurley Street, and 100 Edwin H.

Land Boulevard Mega Campus: Alexandria Center ® at One Kendall Square 1,370,989 — — 1,370,989 12 140,216 88.0 88.0 One Kendall Square (Buildings 100, 200, 300, 400, 500, 600/700, 1400, 1800, and 2000), 325 and 399 Binney Street, and One Hampshire Street Mega Campus: Alexandria Technology Square ® 1,185,284 — — 1,185,284 7 115,886 99.9 99.9 100, 200, 300, 400, 500, 600, and 700 Technology Square Mega Campus: The Arsenal on the Charles 872,883 248,018 — 1,120,901 13 51,957 97.6 97.6 311, 321, and 343 Arsenal Street, 300, 400, and 500 North Beacon Street, 1, 2, 3, and 4 Kingsbury Avenue, and 100, 200, and 400 Talcott Avenue Mega Campus: 480 Arsenal Way and 446, 458, 500, and 550 Arsenal Street 521,735 — — 521,735 5 27,136 99.2 99.2 99 Coolidge Avenue (2) 43,568 277,241 — 320,809 1 5,221 100.0 100.0 Cambridge/Inner Suburbs 6,850,502 525,259 — 7,375,761 49 606,965 97.0 97.0 Fenway Mega Campus: Alexandria Center ® for Life Science – Fenway 1,234,888 450,160 133,578 1,818,626 3 98,035 92.0 83.0 401 and 421 (2) Park Drive and 201 Brookline Avenue (2) Seaport Innovation District 5 and 15 (2) Necco Street 441,396 — — 441,396 2 39,724 75.7 75.7 Seaport Innovation District 441,396 — — 441,396 2 39,724 75.7 75.7 Route 128 Mega Campus: Alexandria Center ® for Life Science – Waltham 326,110 — 716,604 1,042,714 5 22,738 100.0 31.3 40, 50, and 60 Sylvan Road, 35 Gatehouse Drive, and 840 Winter Street Mega Campus: One Moderna Way 706,988 — — 706,988 4 29,059 100.0 100.0 19, 225, and 235 Presidential Way 585,226 — — 585,226 3 13,374 100.0 100.0 Route 128 1,618,324 — 716,604 2,334,928 12 65,171 100.0 69.3 Other 691,633 — 453,869 1,145,502 6 10,864 79.2 47.8 Greater Boston 10,836,743 975,419 1,304,051 13,116,213 72 $ 820,759 94.9 % 84.7 % (1) As of December 31, 2023.

Refer to “New Class A/A+ development and redevelopment properties: summary of pipeline” section within this Item 2 and the definition of “Mega campus” in the “Non-GAAP measures and definitions” section under Item 7 in this annual report on Form 10-K for additional information. (2) We own a partial interest in this property through a real estate joint venture.

Refer to the “Consolidated and unconsolidated real estate joint ventures” section under Item 7 in this annual report in Form 10-K for additional details. 58 Property listing (continued) Occupancy Percentage RSF Number of Properties Annual Rental Revenue Operating Operating and Redevelopment Market / Submarket / Address Operating Development Redevelopment Total San Francisco Bay Area Mission Bay Mega Campus: Alexandria Center ® for Science and Technology – Mission Bay (1) 2,012,791 212,796 — 2,225,587 10 $ 91,856 94.9 % 94.9 % 1455 (2) , 1515 (2) , 1655, and 1725 Third Street, 409 and 499 Illinois Street, 1450, 1500, and 1700 Owens Street, and 455 Mission Bay Boulevard South Mission Bay 2,012,791 212,796 — 2,225,587 10 91,856 94.9 94.9 South San Francisco Mega Campus: Alexandria Technology Center ® – Gateway (1) 1,342,194 — 300,010 1,642,204 12 75,299 86.6 70.8 600 (2) , 601, 611, 630 (2) , 650 (2) , 651, 681, 685, 701, 751, 901 (2) , and 951 (2) Gateway Boulevard Mega Campus: Alexandria Center ® for Advanced Technologies – South San Francisco 919,704 — — 919,704 5 57,055 100.0 100.0 213 (1) , 249, 259, 269, and 279 East Grand Avenue Alexandria Center ® for Life Science – South San Francisco 503,388 — — 503,388 3 32,372 89.8 89.8 201 Haskins Way and 400 and 450 East Jamie Court Mega Campus: Alexandria Center ® for Advanced Technologies – Tanforan 445,232 — — 445,232 2 4,011 100.0 100.0 1122 and 1150 El Camino Real Alexandria Center ® for Life Science – Millbrae (1) — 285,346 — 285,346 1 — N/A N/A 230 Harriet Tubman Way 500 Forbes Boulevard (1) 155,685 — — 155,685 1 10,680 100.0 100.0 South San Francisco 3,366,203 285,346 300,010 3,951,559 24 179,417 93.1 85.5 Greater Stanford Mega Campus: Alexandria Center ® for Life Science – San Carlos 739,157 — — 739,157 9 50,755 99.0 99.0 825, 835, 960, and 1501-1599 Industrial Road Alexandria Stanford Life Science District 703,570 — — 703,570 9 65,005 98.3 98.3 3160, 3165, 3170, and 3181 Porter Drive and 3301, 3303, 3305, 3307, and 3330 Hillview Avenue 3412, 3420, 3440, 3450, and 3460 Hillview Avenue 338,751 — — 338,751 5 24,275 83.2 83.2 3875 Fabian Way 228,000 — — 228,000 1 9,402 100.0 100.0 2475 and 2625/2627/2631 Hanover Street and 1450 Page Mill Road 194,503 — — 194,503 3 18,294 100.0 100.0 2100, 2200, 2300, and 2400 Geng Road 162,584 — — 162,584 4 12,241 100.0 100.0 2425 Garcia Avenue/2400/2450 Bayshore Parkway 99,208 — — 99,208 1 4,257 100.0 100.0 3350 West Bayshore Road 61,431 — — 61,431 1 4,770 100.0 100.0 Greater Stanford 2,527,204 — — 2,527,204 33 188,999 97.0 97.0 San Francisco Bay Area 7,906,198 498,142 300,010 8,704,350 67 460,272 94.8 91.4 New York City New York City Mega Campus: Alexandria Center ® for Life Science – New York City 743,377 — — 743,377 3 67,706 95.8 95.8 430 and 450 East 29th Street Alexandria Center ® for Life Science – Long Island City 179,100 — — 179,100 1 5,287 41.7 41.7 30-02 48th Avenue New York City 922,477 — — 922,477 4 $ 72,993 85.3 % 85.3 % Refer to “New Class A/A+ development and redevelopment properties: summary of pipeline” section within this Item 2 and the definition of “Mega campus” in the “Non-GAAP measures and definitions” section under Item 7 in this annual report on Form 10-K for additional information.

(1) We own a partial interest in this property through a real estate joint venture. Refer to the “Consolidated and unconsolidated real estate joint ventures” section under Item 7 in this annual report in Form 10-K for additional information.

(2) We own 100% of this property. 59 Property listing (continued) Occupancy Percentage RSF Number of Properties Annual Rental Revenue Operating Operating and Redevelopment Market / Submarket / Address Operating Development Redevelopment Total San Diego Torrey Pines Mega Campus: One Alexandria Square 833,589 334,996 — 1,168,585 12 $ 49,861 100.0 % 100.0 % 3115 and 3215 (1) Merryfield Row, 3010, 3013, and 3033 Science Park Road, 10935, 10945, and 10955 Alexandria Way, 10975 North Torrey Pines Road, 10975, 10995, and 10996 Torreyana Road, and 3545 Cray Court ARE Torrey Ridge 296,290 — — 296,290 3 13,969 85.8 85.8 10578, 10618, and 10628 Science Center Drive ARE Nautilus 213,900 — — 213,900 4 8,729 88.2 88.2 3530 and 3550 John Hopkins Court and 3535 and 3565 General Atomics Court Torrey Pines 1,343,779 334,996 — 1,678,775 19 72,559 95.0 95.0 University Town Center Mega Campus: Campus Point by Alexandria (1) 1,666,590 598,029 — 2,264,619 13 77,574 99.0 99.0 9880 (2) , 10010 (2) , 10140 (2) , 10210, 10260, 10290, and 10300 Campus Point Drive and 4135, 4155, 4161, 4224, 4242, and 4275 (2) Campus Point Court Mega Campus: 5200 Illumina Way (1) 792,687 — — 792,687 6 29,978 100.0 100.0 ARE Esplanade 243,084 — — 243,084 4 5,022 47.7 47.7 4755, 4757, and 4767 Nexus Center Drive and 4796 Executive Drive 9625 Towne Centre Drive (1) 163,648 — — 163,648 1 6,528 100.0 100.0 Costa Verde by Alexandria 8,730 — — 8,730 2 879 100.0 100.0 8505 Costa Verde Boulevard and 4260 Nobel Drive University Town Center 2,874,739 598,029 — 3,472,768 26 119,981 95.0 95.0 Sorrento Mesa Mega Campus: SD Tech by Alexandria (1) 1,064,267 254,771 — 1,319,038 15 44,628 95.6 95.6 9605, 9645, 9675, 9685, 9725, 9735, 9808, 9855, and 9868 Scranton Road, 5505 Morehouse Drive (2) , and 10055, 10065, 10075, 10121 (2) , and 10151 (2) Barnes Canyon Road Mega Campus: Sequence District by Alexandria 800,151 — — 800,151 7 23,930 89.0 89.0 6260, 6290, 6310, 6340, 6350, 6420, and 6450 Sequence Drive Pacific Technology Park (1) 544,352 — — 544,352 5 8,969 89.1 89.1 9389, 9393, 9401, 9455, and 9477 Waples Street Summers Ridge Science Park (1) 316,531 — — 316,531 4 11,521 100.0 100.0 9965, 9975, 9985, and 9995 Summers Ridge Road Scripps Science Park by Alexandria 144,113 — — 144,113 1 11,069 100.0 100.0 10102 Hoyt Park Drive ARE Portola 101,857 — — 101,857 3 4,034 100.0 100.0 6175, 6225, and 6275 Nancy Ridge Drive 5810/5820 Nancy Ridge Drive 83,354 — — 83,354 1 4,693 100.0 100.0 9877 Waples Street 63,774 — — 63,774 1 2,680 100.0 100.0 5871 Oberlin Drive 33,842 — — 33,842 1 1,799 100.0 100.0 Sorrento Mesa 3,152,241 254,771 — 3,407,012 38 $ 113,323 93.8 % 93.8 % Refer to “New Class A/A+ development and redevelopment properties: summary of pipeline” section within this Item 2 and the definition of “Mega campus” in the “Non-GAAP measures and definitions” section under Item 7 in this annual report on Form 10-K for additional information.

(1) We own a partial interest in this property through a real estate joint venture. Refer to the “Consolidated and unconsolidated real estate joint ventures” section under Item 7 in this annual report in Form 10-K for additional information.

LEGAL PROCEEDINGS To our knowledge, no legal proceedings are pending against us, other than routine actions and administrative proceedings, and other actions not deemed material, substantially all of which are expected to be covered by liability insurance and which, in the aggregate, are not expected to have a material adverse effect on our financial condition, results of operations, or cash flows.

ITEM 4. MINE SAFETY DISCLOSURES Not applicable. PART II

We cannot assure our stockholders that we will make any future distributions. Refer to “Item 12. Security ownership of certain beneficial owners and management and related stockholder matters” in this annual report on Form 10-K for information on securities authorized for issuance under equity compensation plans. ITEM 6. [RESERVED] 84