In addition, we currently have six6 residential properties (including two 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.

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 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.

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. There can be no assurance that we will not take 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.

We have acquired in the past and in the future may acquire properties or portfolios of properties through tax deferred contribution transactions in exchange for partnership interests in BPLP. This acquisition structure has the effect, among others, of reducing the amount of tax depreciation we can deduct over the tax life of the acquired properties, and typically requires that we agree to protect the contributors’ ability to defer recognition of taxable gain through restrictions on our ability to dispose of the acquired properties and/or the allocation of partnership debt to the contributors to maintain their tax bases. These restrictions could limit our ability to sell an asset at a time, or on terms, that would be favorable absent such restrictions. 

Our ability to dispose of some of our properties is constrained by their tax attributes. Properties which we developed and have owned for a significant period of time or which we acquired through tax deferred contribution transactions in exchange for partnership interests in BPLP often have low tax bases. Furthermore, as a REIT, BXP may be subject to a 100% “prohibited transactions” tax on the gain from dispositions of property if BXP is deemed to hold the property primarily for sale to customers in the ordinary course of business, unless the disposition qualifies under a safe harbor exception for properties that have been held for at least two years and with respect to which certain other requirements are met. The potential application of the prohibited transactions tax could cause us to forego potential dispositions of property or other opportunities that might otherwise be attractive to us, or to undertake such dispositions or other opportunities through a taxable REIT subsidiary, which would generally result in income taxes being incurred. If we dispose of these properties outright in taxable transactions, we may be required to distribute a significant amount of the taxable gain to our securityholders under the requirements of the Internal Revenue Code forapplicable to REITs, which in turn would impact our future cash flow and may increase our leverage. In some cases, without incurring additional costs we may be restricted from disposing of properties contributed in exchange for our partnership interests under tax protection agreements with contributors. To dispose of low basis or tax-protected properties efficiently we from time to time use like-kind exchanges, which are intended to qualify for non-recognition of taxable gain, but can be difficult to consummate and result in the property for which the disposed assets are exchanged inheriting their low tax bases and other tax attributes (including tax protection covenants). 

In addition, because our hotel property is located in Cambridge, Massachusetts, it is subject to the Cambridge market’s fluctuations in demand, increases in operating costs and increased competition from additions in supply.

Certain properties, including the General Motors Building located at 767 Fifth Avenue in New York, New York (“767 Fifth Avenue”), are currently insured in separate insurance programs. The property insurance program per occurrence limits for 767 Fifth Avenue are $1.625 billion, including Terrorism Coverage. We also currently carry nuclear, biological, chemical and radiological terrorism insurance coverage for acts of terrorism certified under the Federal Terrorism Risk Insurance Act (as amended, “TRIA”) (“NBCR Coverage”), which is provided by IXP as a direct insurer, for the properties in our portfolio, including 767 Fifth Avenue, but excluding certain other properties owned in joint ventures with third parties or which we manage. The per occurrence limit for NBCR Coverage is $1.0 billion. Under TRIA, after the payment of the required deductible and coinsurance, the NBCR Coverage provided by IXP is backstopped by the Federal Government if the aggregate industry insured losses resulting from a certified act of terrorism exceed a “program trigger.” In 2018, theThe program trigger was $160is $200 million, the coinsurance is 20% and the coinsurance was 18%, however, both will increase in subsequent years pursuantdeductible is 20% of the premiums earned by the insurer for the year prior to TRIA.a claim. If the Federal Government pays out for a loss under TRIA, it is mandatory that the Federal Government recoup the full amount of the loss from insurers offering TRIA coverage after the payment of the loss pursuant to a formula in TRIA. We may elect to terminate the NBCR Coverage if the Federal Government seeks recoupment for losses paid under TRIA, if TRIA is not extended after its expiration on December 31, 2020,2027, if there is a change in ourits portfolio or for any other reason. We intend to continue to monitor the scope, nature and cost of available terrorism insurance.

IXP, a captive insurance company which is a wholly-owned subsidiary, acts as a direct insurer with respect to a portion of our earthquake insurance coverage for our Greater San Francisco and Los Angeles properties and our NBCR Coverage. Insofar as we own IXP, we are responsible for its liquidity and capital resources, and the accounts of IXP are part of our consolidated financial statements. In particular, if a loss occurs which is covered by our NBCR Coverage but is less than the applicable program trigger under TRIA, IXP would be responsible for the full amount of the loss without any backstop by the Federal Government. IXP would also be responsible for any recoupment charges by the Federal Government in the event losses are paid out and its insurance policy is maintained after the payout by the Federal Government. If we experience a loss and IXP is required to pay under its insurance policy, we would ultimately record the loss to the extent of the required payment. Therefore, insurance coverage provided by IXP should not be considered as the equivalent of third-party insurance, but rather as a modified form of self-insurance. In addition, BPLP has issued a guarantee to cover liabilities of IXP in the amount of $20.0 million.

The mortgages onDue to the current COVID-19 pandemic, we anticipate the possibility of business interruption, loss of lease revenue and/or other associated expenses related to our properties typically contain requirements concerning the financial ratingsoperations across our portfolio. Because this is an ongoing situation it is not yet possible to quantify our losses and expenses, which continue to develop. Because of the insurers who providecomplexity of our insurance policies coveringand limited precedent for claims being made related to pandemics, it is not yet possible to determine if such losses and expenses will be covered by our insurance policies. Therefore, at this time, we have provided notice to the property. We provide the lenders on a regular basis with the identityapplicable insurers of the insurance companiespotential for claims in order to protect our insurance programs. The ratings of some ofrights under our insurers are below the rating requirements in some of our loan agreements and the lenders for these loans could attempt to claim that an event of default has occurred under the loan. We believe we could obtain insurance with insurers which satisfy the rating requirements. Additionally, in the future, our ability to obtain debt financing secured by individual properties, or the terms of such financing, may be adversely affected if lenders generally insist on ratings for insurers or amounts of insurance which are difficult to obtain or which result in a commercially unreasonable premium. There can be no assurance that a deficiency in the financial ratings of one or more of our insurers will not have a material adverse effect on us.policies.

We continue to monitor the state of the insurance market in general, and the scope and costs of coverage for acts of terrorism, earthquakes and California earthquake riskpandemics, in particular, but we cannot anticipate what coverage will be available on commercially reasonable terms in future policy years. There are other types of losses, such as from wars, for which we cannot obtain insurance at all or at a reasonable cost. With respect to such losses and losses from acts of terrorism, earthquakes, pandemics or other catastrophic events, if we experience a loss that is uninsured or that exceeds policy limits, we could lose the capital invested in the damaged properties, as well as the anticipated future revenues from those properties. Depending on the specific circumstances of each affected property, it is possible that we could be liable for mortgage indebtedness or other obligations related to the property. Any such loss could materially and adversely affect our business and financial condition and results of operations.

These costs could be substantial and in extreme cases could exceed the amount of our insurance or the value of the contaminated property. We currently carry environmental insurance in an amount and subject to deductibles that we believe are commercially reasonable. Specifically, we carry a pollution legal liability policy with a $20 million limit per incident and a policy aggregate limit of $40 million. The presence or migration of hazardous or toxic substances or petroleum products or the failure to properly remediate contamination may give rise to third-party claims for bodily injury, property damage and/or response costs and may materially and adversely affect our ability to borrow against, sell or rent an affected property. In addition, applicable environmental laws create liens on contaminated sites in favor of the government for damages and costs it incurs in connection with contamination. Changes in laws, regulations and practices and their implementation increasing the potential liability for environmental conditions existing at our properties, or increasing the restrictions on the handling, storage or discharge of hazardous or toxic substances or petroleum products or other actions may result in significant unanticipated expenditures.

Environmental laws also govern the presence, maintenance and removal of asbestos and other building materials. For example, laws require that owners or operators of buildings containing asbestos: 

Such laws may impose fines and penalties on building owners or operators who fail to comply with these requirements and may allow third parties to seek recovery from owners or operators for personal injury associated with exposure to asbestos fibers. 

Some of our properties are located in urban and previously developed areas where fill or current or historic industrial uses of the areas have caused site contamination. It is our policy to retain independent environmental consultants to conduct or update Phase I environmental site assessments and asbestos surveys with respect to our acquisition of properties. These assessments generally include a visual inspection of the properties and the surrounding areas, an examination of current and historical uses of the properties and the surrounding areas and a review of relevant state, federal and historical documents, but do not involve invasive techniques such as soil and ground water sampling. Where appropriate, on a property-by-property basis, our practice is to have these consultants conduct additional testing, including sampling for asbestos, for lead and other contaminants in drinking water and, for soil and/or groundwater contamination where underground storage tanks are or were located or where other past site usage creates a potential environmental problem. Even though these environmental assessments are conducted, there is still the risk that: 

Inquiries about indoor air quality may necessitate special investigation and, depending on the results, remediation beyond our regular indoor air quality testing and maintenance programs. Indoor air quality issues can stem from inadequate ventilation, chemical contaminants from indoor or outdoor sources, and biological contaminants such as molds, pollen, viruses and bacteria. Indoor exposure to chemical or biological contaminants above certain levels can be alleged to be connected to allergic reactions or other adverse health effects and symptoms in susceptible individuals.effects. If these conditions were to occur at one of our properties, we may be subject to third-party claims for personal injury, or may need to undertake a targeted remediation program, including without limitation, special cleaning measures and steps to increase indoor ventilation rates and eliminate sources of contaminants. Such remediation programs could be costly, necessitate the temporary relocation of some or all of the property’s tenants or require rehabilitation of the affected property. 

From time to time changes in state and local tax laws or regulations are enacted, which may result in an increase in our tax liability. A shortfall in tax revenues for states and municipalities in which we operate may lead to an increase in the frequency and size of such changes. If such changes occur, we may be required to pay additional taxes on our assets or income. These increased tax costs 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.