2. Summary of Significant Accounting Policies

Real Estate

Upon acquisitions of real estate, which includes the consolidation of previously unconsolidated joint ventures, the Company assesses the fair value of acquired tangible and intangible assets (including land, buildings, tenant improvements, “above-” and “below-market” leases, leasing and assumed financing origination costs, acquired in-place leases, other identified intangible assets and assumed liabilities) and allocates the purchase price to the acquired assets and assumed liabilities, including land and buildings as if vacant. The Company assesses and considers fair value based on estimated cash flow projections that utilize discount and/or capitalization rates that it deems appropriate, as well as available market information. Estimates of future cash flows are based on a number of factors including the historical operating results, known and anticipated trends, and market and economic conditions.

The fair value of the tangible assets of an acquired property considers the value of the property as if it were vacant. The Company also considers an allocation of purchase price of other acquired intangibles, including acquired in-place leases that may have a customer relationship intangible value, including (but not limited to) the nature and extent of the existing relationship with the tenants, the tenants’ credit quality and expectations of lease renewals. Based on its acquisitions to date, the Company’s allocation to customer relationship intangible assets has been immaterial.

The Company records acquired “above-” and “below-market” leases at their fair values (using a discount rate which reflects the risks associated with the leases acquired) equal to the difference between (1) the contractual amounts to be paid pursuant to each in-place lease and (2) management’s estimate of fair market lease rates for each corresponding in-place lease, measured over a period equal to the remaining term of the lease for above-market leases and the initial term plus the term of any below-market fixed rate renewal options for below-market leases. Acquired “above-” and “below-market” lease values have been reflected within Prepaid Expenses and Other Assets and Other Liabilities, respectively, in the Company’s Consolidated Balance Sheets. Other intangible assets acquired include amounts for in-place lease values that are based on the Company’s evaluation of the specific characteristics of each tenant’s lease. Factors to be considered include estimates of carrying costs during hypothetical expected lease-up periods considering current market conditions, and costs to execute similar leases. In estimating carrying costs, the Company includes real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, depending on local market conditions. In estimating costs to execute similar leases, the Company considers leasing commissions, legal and other related expenses.

Management reviews its long-lived assets for impairment following the end of each quarter and when there is an event or change in circumstances that indicates an impairment in value. An impairment loss is recognized if the carrying amount of an asset is not recoverable and exceeds its fair value. The evaluation of anticipated cash flows is highly subjective and is based in part on assumptions regarding anticipated hold period, future occupancy, rental rates and capital requirements that could differ materially from actual results in future periods. Because cash flows on properties considered to be “long-lived assets to be held and used” are considered on an undiscounted basis to determine whether an asset has been impaired, the Company’s established strategy of holding properties over the long term directly decreases the likelihood of recording an impairment loss. If the Company’s strategy changes or market conditions otherwise dictate an earlier sale date, an impairment loss may be recognized and such loss could be material. If the Company determines that an impairment has occurred, the affected assets must be reduced to their fair value, less cost to sell.

Guidance in Accounting Standards Codification (“ASC”) 360 “Property Plant and Equipment” (“ASC 360”) requires that qualifying assets and liabilities and the results of operations that have been sold, or otherwise qualify as “held for sale,” be presented as discontinued operations in all periods presented if the property operations are expected to be eliminated and the Company will not have significant continuing involvement following the sale. Discontinued operations presentation applies only to disposals representing a strategic shift that has (or will have) a major effect on an entity’s operations and financial results (e.g., a disposal of a major geographical area, a major line of business, a major equity method investment or other major parts of an entity). The components of the property’s net income that are reflected as discontinued operations include the net gain (or loss) upon the disposition of the property held for sale, operating results, depreciation and interest expense (if the property is subject to a secured loan). The Company generally considers assets to be “held for sale” when the transaction has been approved by Boston Properties, Inc.’s Board of Directors, or a committee thereof, and there are no known significant contingencies relating to the sale, such that a sale of the property within one year is considered probable. Following the classification of a property as “held for sale,” no further depreciation is recorded on the assets, and the asset is written down to the lower of carrying value or fair market value, less cost to sell.

Real estate is stated at depreciated cost. A variety of costs are incurred in the acquisition, development and leasing of properties. The cost of buildings and improvements includes the purchase price of property, legal fees and other acquisition costs. The Company capitalizes acquisition costs that it incurs to effect an asset acquisition and expenses acquisition costs that it incurs to effect a business combination, including legal, due diligence and other closing related costs. Costs directly related to the development of properties are capitalized. Capitalized development costs include interest, internal wages, property taxes, insurance, and other project costs incurred during the period of development. After the determination is made to capitalize a cost, it is allocated to the specific component of a project that is benefited. Determination of when a development project commences and capitalization begins, and when a development project is substantially complete and held available for occupancy and capitalization must cease, involves a degree of judgment. The Company’s capitalization policy on development properties follows the guidance in ASC 835-20 “Capitalization of Interest” and ASC 970 “Real Estate-General.” The costs of land and buildings under development include specifically identifiable costs.

The capitalized costs include pre-construction costs necessary to the development of the property, development costs, construction costs, interest costs, real estate taxes, salaries and related costs and other costs incurred during the period of development. The Company begins the capitalization of costs during the pre-construction period which it defines as activities that are necessary for the development of the property. The Company considers a construction project as substantially completed and held available for occupancy upon the completion of tenant improvements, but no later than one year from cessation of major construction activity. The Company ceases capitalization on the portion (1) substantially completed, (2) occupied or held available for occupancy, and capitalizes only those costs associated with the portion under construction or (3) if activities necessary for the development of the property have been suspended. Interest costs capitalized for the years ended December 31, 2017, 2016 and 2015 were $61.1 million, $39.2 million and $34.2 million, respectively. Salaries and related costs capitalized for the years ended December 31, 2017, 2016 and 2015 were $13.2 million, $11.1 million and $10.4 million, respectively.

Expenditures for repairs and maintenance are charged to operations as incurred. Significant betterments are capitalized. When assets are sold or retired, their costs and related accumulated depreciation are removed from the accounts with the resulting gains or losses reflected in net income or loss for the period.

The Company computes depreciation and amortization on properties using the straight-line method based on estimated useful asset lives. In accordance with ASC 805 “Business Combinations,” the Company allocates the acquisition cost of real estate to its components and depreciates or amortizes these assets (or liabilities) over their useful lives. The amortization of acquired “above-” and “below-market” leases and acquired in-place leases is recorded as an adjustment to revenue and depreciation and amortization, respectively, in the Consolidated Statements of Operations.

Depreciation is computed on a straight-line basis over the estimated useful lives of the assets as follows:



Land improvements		25 to 40 years
Buildings and improvements		10 to 40 years
Tenant improvements		Shorter of useful life or terms of related lease
Furniture, fixtures, and equipment		3 to 7 years

Cash and Cash Equivalents

Cash and cash equivalents consist of cash on hand and investments with maturities of three months or less from the date of purchase. The majority of the Company’s cash and cash equivalents are held at major commercial banks which may at times exceed the Federal Deposit Insurance Corporation limit of $250,000.

Cash Held in Escrows

Escrows include amounts established pursuant to various agreements for security deposits, property taxes, insurance and other costs. Escrows also include cash held by qualified intermediaries for possible investments in like-kind exchanges in accordance with Section 1031 of the Internal Revenue Code in connection with sales of the Company’s properties.

Investments in Securities

The Company accounts for investments in trading securities at fair value, with gains or losses resulting from changes in fair value recognized currently in earnings. The designation of trading securities is generally determined at acquisition. The Company maintains a deferred compensation plan that is designed to allow officers of Boston Properties, Inc. to defer a portion of their current income on a pre-tax basis and receive a tax-deferred return on these deferrals. The Company’s obligation under the plan is that of an unsecured promise to pay the deferred compensation to the plan participants in the future. At December 31, 2017 and 2016, the Company had maintained approximately $29.2 million and $23.8 million, respectively, in a separate account, which is not restricted as to its use. The Company recognized gains (losses) of approximately $3.7 million, $2.3 million and $(0.7) million on its investments in the account associated with the Company’s deferred compensation plan during the years ended December 31, 2017, 2016 and 2015, respectively.

Tenant and Other Receivables

Tenant and other accounts receivable, other than accrued rents receivable, are expected to be collected within one year.

Deferred Charges

Deferred charges include leasing costs and certain financing fees. Leasing costs include acquired intangible in-place lease values and direct and incremental fees and costs incurred in the successful negotiation of leases, including brokerage, legal, internal leasing employee salaries and other costs which have been deferred and are being amortized on a straight-line basis over the terms of the respective leases. Unamortized leasing costs are charged to expense upon the early termination of the lease. Fully amortized deferred leasing costs are removed from the books upon the expiration of the lease. Internal leasing salaries and related costs capitalized for the years ended December 31, 2017, 2016 and 2015 were $5.0 million, $7.2 million and $5.5 million, respectively. Financing fees included in deferred charges consist of external fees and costs incurred to obtain the Company's revolving facility and if applicable, the delayed draw facility and construction financing arrangements where there are not sufficient amounts outstanding. Such financing costs have been deferred and are being amortized over the terms of the respective financing and included within interest expense. Unamortized financing costs are charged to expense upon the early repayment or significant modification of the financing. Fully amortized deferred financing costs are removed from the books upon the maturity of the debt.

External fees and costs incurred to obtain mortgage financings and unsecured senior notes have been deferred and are presented as direct deductions from the carrying amounts of the corresponding debt liability. Such financing costs are being amortized over the terms of the respective financing and included within interest expense. Unamortized financing costs are charged to expense upon the early repayment or significant modification of the financing.

Investments in Unconsolidated Joint Ventures

The Company consolidates VIEs in which it is considered to be the primary beneficiary. VIEs are entities in which the equity investors do not have sufficient equity at risk to finance their endeavors without additional financial support or that the holders of the equity investment at risk do not have substantive participating rights. The primary beneficiary is defined by the entity having both of the following characteristics: (1) the power to direct the activities that, when taken together, most significantly impact the variable interest entity’s performance, and (2) the obligation to absorb losses and the right to receive the returns from the variable interest entity that could potentially be significant to the VIE. For ventures that are not VIEs, the Company consolidates entities for which it has significant decision making control over the ventures’ operations. The Company’s judgment with respect to its level of influence or control of an entity involves the consideration of various factors including the form of the Company’s ownership interest, its representation in the entity’s governance, the size of its investment (including loans), estimates of future cash flows, its ability to participate in policy making decisions and the rights of the other investors to participate in the decision making process and to replace the Company as manager and/or liquidate the venture, if applicable. The Company’s assessment of its influence or control over an entity affects the presentation of these investments in the Company’s consolidated financial statements. In addition to evaluating control rights, the Company consolidates entities in which the outside partner has no substantive kick-out rights to remove the Company as the managing member.

Accounts of the consolidated entity are included in the accounts of the Company and the noncontrolling interest is reflected on the Consolidated Balance Sheets as a component of equity or in temporary equity between liabilities and equity. Investments in unconsolidated joint ventures are recorded initially at cost, and subsequently adjusted for equity in earnings and cash contributions and distributions. Any difference between the carrying amount of these investments on the balance sheet and the underlying equity in net assets is amortized as an adjustment to equity in earnings of unconsolidated joint ventures over the life of the related asset. Under the equity method of accounting, the net equity investment of the Company is reflected within the Consolidated Balance Sheets, and the Company’s share of net income or loss from the joint ventures is included within the Consolidated Statements of Operations. The joint venture agreements may designate different percentage allocations among investors for profits and losses; however, the Company’s recognition of joint venture income or loss generally follows the joint venture’s distribution priorities, which may change upon the achievement of certain investment return thresholds. The Company may account for cash distributions in excess of its investment in an unconsolidated joint venture as income when the Company is not the general partner in a limited partnership and when the Company has neither the requirement nor the intent to provide financial support to the joint venture. The Company’s investments in unconsolidated joint ventures are reviewed for impairment periodically and the Company records impairment charges when events or circumstances change indicating that a decline in the fair values below the carrying values has occurred and such decline is other-than-temporary. The ultimate realization of the investment in unconsolidated joint ventures is dependent on a number of factors, including the performance of each investment and market conditions. The Company will record an impairment charge if it determines that a decline in the value below the carrying value of an investment in an unconsolidated joint venture is other-than-temporary.

To the extent that the Company contributes assets to a joint venture, the Company’s investment in the joint venture is recorded at the Company’s cost basis in the assets that were contributed to the joint venture. To the extent that the Company’s cost basis is different than the basis reflected at the joint venture level, the basis difference is amortized over the life of the related asset and included in the Company’s share of equity in net income of the joint venture. In accordance with the provisions of ASC 970-323 “Investments—Equity Method and Joint Ventures” (“ASC 970-323”), the Company will recognize gains on the contribution of real estate to joint ventures, relating solely to the outside partner’s interest, to the extent the economic substance of the transaction is a sale.

The combined summarized financial information of the unconsolidated joint ventures is disclosed in Note 5.

Revenue Recognition

In general, the Company commences rental revenue recognition when the tenant takes possession of the leased space and the leased space is substantially ready for its intended use. Contractual rental revenue is reported on a straight-line basis over the terms of the respective leases. The impact of the straight-line rent adjustment increased revenue by approximately $54.8 million, $31.7 million and $80.0 million for the years ended December 31, 2017, 2016 and 2015, respectively, as the revenue recorded exceeded amounts billed. Accrued rental income, as reported on the Consolidated Balance Sheets, represents cumulative rental income earned in excess of rent payments received pursuant to the terms of the individual lease agreements. The Company maintains an allowance against accrued rental income for future potential tenant credit losses. The credit assessment is based on the estimated accrued rental income that is recoverable over the term of the lease. The Company also maintains an allowance for doubtful accounts for estimated losses resulting from the inability of tenants to make required rent payments. The computation of this allowance is based on the tenants’ payment history and current credit status, as well as certain industry or geographic specific credit considerations. If the Company’s estimates of collectability differ from the cash received, then the timing and amount of the Company’s reported revenue could be impacted. The credit risk is mitigated by the high quality of the Company’s existing tenant base, reviews of prospective tenants’ risk profiles prior to lease execution and consistent monitoring of the Company’s portfolio to identify potential problem tenants.

In accordance with ASC 805, the Company recognizes acquired in-place “above-” and “below-market” leases at their fair values as rental revenue over the original term of the respective leases. The impact of the acquired in-place “above-” and “below-market” leases increased revenue by approximately $23.5 million, $30.2 million and $35.9 million for the years ended December 31, 2017, 2016 and 2015, respectively. The following table summarizes the scheduled amortization of the Company’s acquired “above-” and “below-market” lease intangibles for each of the five succeeding years (in thousands).



	Acquired Above-Market Lease Intangibles		Acquired Below-Market Lease Intangibles
2018	$	8,614	$	32,152
2019	7,106		27,281
2020	5,394		10,736
2021	2,988		6,399
2022	315		5,669

Recoveries from tenants, consisting of amounts due from tenants for common area maintenance, real estate taxes and other recoverable costs, are recognized as revenue in the period during which the expenses are incurred. Tenant reimbursements are recognized and presented in accordance with guidance in ASC 605-45 “Principal Agent Considerations” (“ASC 605-45”). ASC 605-45 requires that these reimbursements be recorded on a gross basis, as the Company is generally the primary obligor with respect to purchasing goods and services from third-party suppliers, has discretion in selecting the supplier and has credit risk. The Company also receives reimbursement of payroll and payroll related costs from third parties which the Company reflects on a net basis.

The Company’s parking revenues are derived from leases, monthly parking and transient parking. The Company recognizes parking revenue as earned.

The Company’s hotel revenue is derived from room rentals and other sources such as charges to guests for telephone service, movie and vending commissions, meeting and banquet room revenue and laundry services. Hotel revenue is recognized as earned.

The Company receives management and development fees from third parties. Property management fees are recorded and earned based on a percentage of collected rents at the properties under management, and not on a straight-line basis, because such fees are contingent upon the collection of rents. The Company records development fees as earned depending on the risk associated with each project. The Company recognizes development fees earned from joint venture projects equal to its cost plus profit to the extent of the third party partners’ ownership interest.

Gains on sales of real estate are recognized pursuant to the provisions included in ASC 360-20 “Real Estate Sales” (“ASC 360-20”). The specific timing of the sale is measured against various criteria in ASC 360-20 related to the terms of the transaction and any continuing involvement in the form of management or financial assistance associated with the properties. If the sales criteria for the full accrual method are not met, the Company defers some or all of the gain recognition and accounts for the continued operations of the property by applying the finance, leasing, profit sharing, deposit, installment or cost recovery methods, as appropriate, until the sales criteria are met.

Ground Leases

The Company has non-cancelable ground lease obligations with various initial term expiration dates through 2114. The Company recognizes ground rent expense on a straight-line basis over the terms of the respective ground lease agreements. The future contractual minimum lease payments to be made by the Company as of December 31, 2017, under non-cancelable ground leases which expire on various dates through 2114, are as follows:



Years Ending December 31,	(in thousands)
2018	$	11,349
2019	16,360
2020	25,552
2021	11,814
2022	8,894
Thereafter	576,315

Capital Leases

The Company has three capital lease obligations with various initial term expiration dates through 2036. The following reflects the gross amount of assets recorded under capital leases by asset class at December 31, 2017 and December 31, 2016 (in thousands):



	December 31,
	2017		2016
Buildings and improvements	$	23,636	$	23,636
Construction in progress	28,962		—
Total	$	52,598	$	23,636

The future minimum lease payments, as of December 31, 2017, related to the three capital leases, through 2036 are as follows:



Years Ending December 31,	(in thousands)
2018	$	913
2019	1,392
2020	2,097
2021	1,375
2022	930
Thereafter	74,185
Total expected minimum lease payments	80,892
Interest portion	(29,296		)
Present value of expected net minimum lease payments	$	51,596

Earnings Per Share

Basic earnings per share (“EPS”) is computed by dividing net income available to common shareholders, as adjusted for undistributed earnings (if any) of certain securities issued by Boston Properties Limited Partnership, by the weighted average number of shares of Common Stock outstanding during the year. Diluted EPS reflects the potential dilution that could occur from shares issuable in connection with awards under stock-based compensation plans, including upon the exercise of stock options, and securities of Boston Properties Limited Partnership that are exchangeable for Common Stock.

Earnings Per Common Unit

Basic earnings per common unit is computed by dividing net income available to common unitholders, as adjusted for undistributed earnings (if any) of certain securities issued by Boston Properties Limited Partnership, by the weighted average number of common units outstanding during the year. Diluted earnings per common unit reflects the potential dilution that could occur from units issuable in connection with awards under Boston Properties, Inc.’s stock-based compensation plans, including upon the exercise of stock options, and conversion of preferred units of Boston Properties Limited Partnership.

Fair Value of Financial Instruments

The carrying values of cash and cash equivalents, marketable securities, escrows, receivables, accounts payable, accrued expenses and other assets and liabilities are reasonable estimates of their fair values because of the short maturities of these instruments.

The Company follows the authoritative guidance for fair value measurements when valuing its financial instruments for disclosure purposes. Boston Properties Limited Partnership determines the fair value of its unsecured senior notes using market prices. The inputs used in determining the fair value of Boston Properties Limited Partnership’s unsecured senior notes is categorized at a Level 1 basis (as defined in ASC 820 "Fair Value Measurements and Disclosures", the accounting standards for Fair Value Measurements and Disclosures) due to the fact that it uses quoted market rates to value these instruments. However, the inputs used in determining the fair value could be categorized at a level 2 basis (as defined in the accounting standards for Fair Value Measurements and Disclosures) if trading volumes are low. The Company determines the fair value of its mortgage notes payable using discounted cash flow analysis by discounting the spread between the future contractual interest payments and hypothetical future interest payments on mortgage debt based on current market rates for similar securities. In determining the current market rates, the Company adds its estimates of market spreads to the quoted yields on federal government treasury securities with similar maturity dates to its debt. The inputs used in determining the fair value of the Company’s mortgage notes payable and mezzanine notes payable are categorized at a level 3 basis (as defined in the accounting standards for Fair Value Measurements and Disclosures) due to the fact that the Company considers the rates used in the valuation techniques to be unobservable inputs. To the extent that there are outstanding borrowings under the unsecured line of credit, the Company utilizes a discounted cash flow methodology in order to estimate the fair value. To the extent that credit spreads have changed since the origination, the net present value of the difference between future contractual interest payments and future interest payments based on the Company’s estimate of a current market rate would represent the difference between the book value and the fair value. The Company’s estimate of a current market rate is based upon the rate, considering current market conditions and the Company’s specific credit profile, at which it estimates it could obtain similar borrowings. To the extent there are outstanding borrowings, this current market rate is estimated and therefore would be primarily based upon a level 3 input.

Because the Company’s valuations of its financial instruments are based on these types of estimates, the actual fair values of its financial instruments may differ materially if the Company’s estimates do not prove to be accurate, and the Company’s estimated fair values for these instruments as of the end of the applicable reporting period are not necessarily indicative of estimated or actual fair values in future reporting periods. The following table presents the aggregate carrying value of the Company’s mortgage notes payable, net, mezzanine notes payable, unsecured senior notes, net and unsecured line of credit and the Company’s corresponding estimate of fair value as of December 31, 2017 and December 31, 2016 (in thousands):



	December 31, 2017				December 31, 2016
	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Mortgage notes payable, net	$	2,979,281	$	3,042,920	$	2,063,087	$	2,092,237
Mezzanine notes payable	—		—		307,093		308,344
Unsecured senior notes, net	7,247,330		7,461,615		7,245,953		7,428,077
Unsecured line of credit	45,000		45,000		—		—
Total	$	10,271,611	$	10,549,535	$	9,616,133	$	9,828,658

The Company uses interest rate swap agreements to manage its interest rate risk. The valuation of these instruments is determined using widely accepted valuation techniques, including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. To comply with the provisions of ASC 820, the Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. Although the Company determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by the Company and its counterparties. The Company assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and determined that the credit valuation adjustments were not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy.

Derivative Instruments and Hedging Activities

Derivative instruments and hedging activities require management to make judgments on the nature of its derivatives and their effectiveness as hedges. These judgments determine if the changes in fair value of the derivative instruments are reported in the Consolidated Statements of Operations as a component of net income or as a component of comprehensive income and as a component of equity on the Consolidated Balance Sheets. While management believes its judgments are reasonable, a change in a derivative’s effectiveness as a hedge could materially affect expenses, net income and equity. The Company accounts for the effective portion of changes in the fair value of a derivative in other comprehensive income (loss) and subsequently reclassifies the effective portion to earnings over the term that the hedged transaction affects earnings. The Company accounts for the ineffective portion of changes in the fair value of a derivative directly in earnings.

Stock-Based Employee Compensation Plans

At December 31, 2017, the Company has a stock-based employee compensation plan. The Company accounts for the plan under the guidance in ASC 718 “Compensation – Stock Compensation” (“ASC 718”), which revised the fair value based method of accounting for share-based payment liabilities, forfeitures and modifications of stock-based awards and clarified previous guidance in several areas, including measuring fair value, classifying an award as equity or as a liability and attributing compensation cost to reporting periods.

Use of Estimates in the Preparation of Financial Statements

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. These estimates include such items as depreciation and allowances for doubtful accounts. Actual results could differ from those estimates.

Recent Accounting Pronouncements

In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”). The objective of ASU 2014-09 is to establish a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and will supersede most of the existing revenue recognition guidance, including industry-specific guidance. The core principle is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In applying ASU 2014-09, companies will perform a five-step analysis of transactions to determine when and how revenue is recognized. ASU 2014-09 applies to all contracts with customers except those that are within the scope of other topics in the FASB’s ASC. In August 2015, the FASB issued ASU 2015-14, “Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date” (“ASU 2015-14”), which delayed the effective date of ASU 2014-09 by one year making it effective for the first interim period within annual reporting periods beginning after December 15, 2017. Early adoption is permitted as of the original effective date. In May 2016, the FASB issued ASU No. 2016-12, “Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients” (“ASU 2016-12”). ASU 2016-12 is intended to clarify and provide practical expedients for certain aspects of ASU 2014-09, which outlines a single comprehensive model for entities to use in accounting for revenues arising from contracts with customers and notes that lease contracts with customers are a scope exception. ASU 2014-09 is effective for the Company for reporting periods beginning after December 15, 2017. The Company adopted ASU 2014-09 effective January 1, 2018 using the modified retrospective approach. The Company expects that executory costs and certain non-lease components of revenue from leases may be impacted by the adoption of ASU 2014-09 (upon the adoption of ASU 2016-02). The adoption of ASU 2014-09 is expected to result in a change to the timing pattern of revenue recognized, but not the total revenue recognized over time for certain of the Company’s development services revenue. As a result, the modified retrospective approach is expected to result in the Company recognizing on January 1, 2018 the cumulative effect of adopting ASU 2014-09 reflecting the impact of applying the new guidance to certain of the Company’s outstanding development services contracts. ASU 2014-09 also updates the principal versus agent considerations and as a result the Company determined that amounts reimbursed for payroll and related costs received from third parties in connection with management services contracts should be reflected on a gross basis instead of on a net basis as the Company has determined that it is the principal under these arrangements. The adoption of ASU 2014-09 will not have a material impact on the Company’s consolidated financial statements.

In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” (“ASU 2016-02”), which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). ASU 2016-02 requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase of the leased asset by the lessee. This classification will determine whether the lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases today. The new standard requires lessors to account for leases using an approach that is substantially equivalent to existing guidance for sales-type leases, direct financing leases and operating leases. ASU 2016-02 supersedes previous leasing standards. ASU 2016-02 is effective for the Company for reporting periods beginning after December 15, 2018, with early adoption permitted. The Company will adopt ASU 2016-02 effective January 1, 2019 using the modified retrospective approach. The Company is in the process of evaluating whether it will elect to apply the practical expedients. The Company is in the process of adopting ASU 2016-02, with its project team compiling an inventory of its leases that will be impacted by the adoption of ASU 2016-02. The Company continues to assess the impact of adopting ASU 2016-02. However, the Company will account for operating leases under which it is the lessor on its balance sheet in a manner similar to its current accounting with the underlying leased asset recognized as real estate. In January 2018, the FASB issued a proposed ASU that would allow lessors to elect, as a practical expedient, not to allocate the total consideration to lease and non-lease components based on their relative standalone selling prices. If issued, this practical expedient will allow lessors to elect a combined single lease component presentation if (i) the timing and pattern of the revenue recognition of the combined single lease component is the same, and (ii) the related lease component and, the combined single lease component would be classified as an operating lease. If the practical expedient in the proposed ASU is issued, it could allow for tenant recoveries that qualify as non-lease components to be presented under a single lease component presentation. However, without the proposed practical expedient, tenant recoveries would be separated into lease and non-lease components. For leases in which the Company is the lessee, primarily consisting of ground leases, the Company will recognize a right-of-use asset and a lease liability equal to the present value of the minimum lease payments with rental payments being applied to the lease liability and to interest expense and the right-of-use asset being amortized to expense over the term of the lease. In addition, under ASU 2016-02, lessors will only capitalize incremental direct leasing costs. As a result, the Company will no longer be able to capitalize legal costs and internal leasing wages and instead will be required to expense these and other non-incremental costs as incurred.

In March 2016, the FASB issued ASU 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting” (“ASU 2016-09”). ASU 2016-09 is intended to improve the accounting for share-based payments and affects all organizations that issue share-based payment awards to their employees. Several aspects of the accounting for share-based payment awards are simplified with ASU 2016-09, including income tax consequences, classification of awards as equity or liabilities and classification on the statement of cash flows. ASU 2016-09 is effective for the Company for reporting periods beginning after December 15, 2016, with early adoption permitted. On January 1, 2017, the Company adopted ASU 2016-09 and elected to make an accounting policy change to its method of accounting for forfeitures on its awards of stock-based compensation including the issuance of shares of restricted common stock, LTIP Units and MYLTIP Units. The Company now accounts for forfeitures as they occur instead of estimating the number of forfeitures upon the issuance of such awards of stock-based compensation. The adoption resulted in the Company recognizing cumulative effect of a change in accounting principle adjustments to its consolidated balance sheets totaling approximately $0.3 million to Dividends in Excess of Earnings and Partners’ Capital for Boston Properties, Inc. and Boston Properties Limited Partnership, respectively, and approximately $1.8 million to noncontrolling interests - common units of Boston Properties Limited Partnership and noncontrolling interests - redeemable partnership units for Boston Properties, Inc. and Boston Properties Limited Partnership, respectively.

In August 2016, the FASB issued ASU No. 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the FASB Emerging Issues Task Force)” (“ASU 2016-15”). ASU 2016-15 is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. The areas addressed in the new guidance related to debt prepayment costs, settlement of zero-coupon debt instruments, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, proceeds from the settlement of corporate-owned and bank-owned life insurance policies, distributions received from equity method investments, beneficial interest in securitization transactions, and separately identifiable cash flows and application of the predominance principle. ASU 2016-15 is effective for the Company for reporting periods beginning after December 15, 2017, with early adoption permitted (provided that all of the amendments are adopted in the same period), and will be applied retrospectively to all periods presented. The Company adopted ASU 2016-15 effective January 1, 2018. The adoption of ASU 2016-15 will result in the retrospective classification of debt prepayment costs as financing activities instead of operating activities in the Company's consolidated statements of cash flows.

In November 2016, the FASB issued ASU No. 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force)” (“ASU 2016-18”). ASU 2016-18 will require companies to include restricted cash and restricted cash equivalents with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 will require a disclosure of a reconciliation between the statement of financial position and the statement of cash flows when the statement of financial position includes more than one line item for cash, cash equivalents, restricted cash and restricted cash equivalents. Entities with material restricted cash and restricted cash equivalents balances will be required to disclose the nature of the restrictions. ASU 2016-18 is effective for reporting periods beginning after December 15, 2017, with early adoption permitted, and will be applied retrospectively to all periods presented. The Company adopted ASU 2016-18 effective January 1, 2018. The adoption of ASU 2016-18 will not have a material impact on the Company’s consolidated financial statements.

In January 2017, the FASB issued ASU 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business” (“ASU 2017-01”). ASU 2017-01 clarifies the framework for determining whether an integrated set of assets and activities meets the definition of a business. The revised framework establishes a screen for determining whether an integrated set of assets and activities is a business and narrows the definition of a business, which is expected to result in fewer transactions being accounted for as business combinations. Acquisitions of integrated sets of assets and activities that do not meet the definition of a business are accounted for as asset acquisitions. This update is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2017, with early adoption permitted for transactions that have not been reported in previously issued (or available to be issued) financial statements and shall be applied on a prospective basis. The Company early adopted ASU 2017-01 during the first quarter of 2017. The Company expects that acquisitions of real estate or in-substance real estate will not meet the revised definition of a business because substantially all of the fair value is concentrated in a single identifiable asset or group of similar identifiable assets (i.e. land, buildings, and related intangible assets) or because the acquisition does not include a substantive process in the form of an acquired workforce or an acquired contract that cannot be replaced without significant cost, effort or delay.

In February 2017, the FASB issued ASU No. 2017-05, “Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets” (“ASU 2017-05”). ASU 2017-05 updates the definition of an “in substance nonfinancial asset” and clarifies the derecognition guidance for nonfinancial assets to conform with the new revenue recognition standard. The effective date and transition methods of ASU 2017-05 are aligned with ASU 2014-09 described above and are effective for the first interim period within annual reporting periods beginning after December 15, 2017. The Company adopted ASU 2017-05 effective January 1, 2018 using the modified retrospective approach. The adoption of ASU 2017-05 will not have a material impact on the Company's consolidated financial statements.

In May 2017, the FASB issued ASU 2017-09, “Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting” (“ASU 2017-09”). ASU 2017-09 is intended to provide clarity and reduce (1) diversity in practice, (2) cost and (3) complexity when applying the guidance in Topic 718 to a change to the terms or conditions of a share-based payment award. ASU 2017-09 is effective for public entities for fiscal years and interim periods beginning after December 15, 2017. The Company adopted ASU 2017-09 effective January 1, 2018. The adoption of ASU 2017-09 will not have a material impact on the Company's consolidated financial statements.

In August 2017, the FASB issued ASU 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities” (“ASU 2017-12”). ASU 2017-12 was issued with the objective of improving the financial reporting of hedging relationships to better portray the economic results of an entity’s risk management activities in its financial statements. ASU 2017-12 also makes certain targeted improvements to simplify the application of the hedge accounting guidance. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. The Company early adopted ASU 2017-12 effective January 1, 2018. The adoption of ASU 2017-12 will not have a material impact on the Company's consolidated financial statements.

Boston Properties, Inc.

Equity Offering Costs

Underwriting commissions and offering costs have been reflected as a reduction of additional paid-in capital.

Treasury Stock

Boston Properties, Inc.’s share repurchases are reflected as treasury stock utilizing the cost method of accounting and are presented as a reduction to consolidated stockholders’ equity.

Dividends

Earnings and profits, which determine the taxability of dividends to stockholders, will differ from income reported for financial reporting purposes due to the differences for federal income tax purposes in the treatment of gains/losses on the sale of real property, revenue and expense recognition, compensation expense, and in the estimated useful lives and basis used to compute depreciation.

The tax treatment of common dividends per share for federal income tax purposes is as follows:



	For the year ended December 31,
	2017					2016					2015
	Per Share			%		Per Share			%		Per Share			%
Ordinary income	$	2.86		98.29	%	$	2.76		90.51	%	$	2.34		57.97	%
Capital gain income	0.05			1.71	%	0.29			9.49	%	1.70			42.03	%
Total	$	2.91	(1)	100.00	%	$	3.05	(2)	100.00	%	$	4.04	(3)	100.00	%

_____________


(1)	The fourth quarter 2017 regular quarterly dividend was $0.80 per common share of which approximately $0.47 per common share was allocable to 2017 and approximately $0.33 per common share is allocable to 2018.


(2)	The fourth quarter 2016 regular quarterly dividend was $0.75 per common share of which approximately $0.56 per common share was allocable to 2016 and approximately $0.19 per common share is allocable to 2017.


(3)	The fourth quarter 2015 dividend of $1.90 per common share consists of a $1.25 per common share special dividend and a $0.65 per common share regular quarterly dividend. Approximately $1.35 per common share was allocable to 2015 and approximately $0.55 per common share is allocable to 2016.

Income Taxes

Boston Properties, Inc. has elected to be treated as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”), commencing with its taxable year ended December 31, 1997. As a result, it generally will not be subject to federal corporate income tax on its taxable income that is distributed to its stockholders. A REIT is subject to a number of organizational and operational requirements, including a requirement that it currently distribute at least 90% of its annual taxable income (with certain adjustments). Boston Properties, Inc.’s policy is to distribute at least 100% of its taxable income. Accordingly, the only provision for federal income taxes in the accompanying consolidated financial statements relates to Boston Properties, Inc.’s consolidated taxable REIT subsidiaries. Boston Properties, Inc.’s taxable REIT subsidiaries did not have significant tax provisions or deferred income tax items. Boston Properties, Inc. has no uncertain tax positions recognized as of December 31, 2017 and 2016.

The Company owns a hotel property that is leased by a taxable REIT subsidiary and managed by Marriott International, Inc. The hotel taxable REIT subsidiary, a wholly owned subsidiary of Boston Properties Limited Partnership, is the lessee pursuant to the lease for the hotel property. As lessor, Boston Properties Limited Partnership is entitled to a percentage of gross receipts from the hotel property. Marriott International, Inc. continues to manage the hotel property under the Marriott name and under terms of the existing management agreement. The hotel taxable REIT subsidiary is subject to tax at the federal and state level and, accordingly, Boston Properties, Inc. has recorded a tax provision in its Consolidated Statements of Operations for the years ended December 31, 2017, 2016 and 2015.

The net difference between the tax basis and the reported amounts of Boston Properties, Inc.’s assets and liabilities is approximately $1.8 billion and $1.7 billion as of December 31, 2017 and 2016, respectively, which is primarily related to the difference in basis of contributed property and accrued rental income.

Certain entities included in Boston Properties, Inc.’s consolidated financial statements are subject to certain state and local taxes. These taxes are recorded as operating expenses in the accompanying consolidated financial statements.

The following table reconciles GAAP net income attributable to Boston Properties, Inc. to taxable income (unaudited):



	For the year ended December 31,
	2017			2016			2015
	(in thousands)
Net income attributable to Boston Properties, Inc.	$	462,439		$	512,785		$	583,106
Straight-line rent and net “above-” and “below-market” rent adjustments	(77,801		)	(65,861		)	(92,483		)
Book/Tax differences from depreciation and amortization	142,234			235,819			307,115
Book/Tax differences from interest expense	(18,136		)	(36,223		)	(43,349		)
Book/Tax differences on gains/(losses) from capital transactions	1,123			(70,880		)	(74,482		)
Book/Tax differences from stock-based compensation	37,990			33,463			22,008
Tangible Property Regulations	(116,265		)	(104,783		)	(74,887		)
Other book/tax differences, net	33,411			(6,121		)	(15,259		)
Taxable income	$	464,995		$	498,199		$	611,769

Boston Properties Limited Partnership

Income Taxes

The partners are required to report their respective share of Boston Properties Limited Partnership’s taxable income or loss on their respective tax returns and are liable for any related taxes thereon. Accordingly, the only provision for federal income taxes in the accompanying consolidated financial statements relates to Boston Properties Limited Partnership’s consolidated taxable REIT subsidiaries. Boston Properties Limited Partnership’s taxable REIT subsidiaries did not have significant tax provisions or deferred income tax items. Boston Properties Limited Partnership has no uncertain tax positions recognized as of December 31, 2017 and 2016.

The Company owns a hotel property which is managed through a taxable REIT subsidiary. The hotel taxable REIT subsidiary, a wholly owned subsidiary Boston Properties Limited Partnership, is the lessee pursuant to the lease for the hotel property. As lessor, Boston Properties Limited Partnership is entitled to a percentage of gross receipts from the hotel property. Marriott International, Inc. continues to manage the hotel property under the Marriott name and under terms of the existing management agreement. The hotel taxable REIT subsidiary is subject to tax at the federal and state level and, accordingly, Boston Properties Limited Partnership has recorded a tax provision in its Consolidated Statements of Operations for the years ended December 31, 2017, 2016 and 2015.

The net difference between the tax basis and the reported amounts of Boston Properties Limited Partnership’s assets and liabilities is approximately $2.9 billion and $2.7 billion as of December 31, 2017 and 2016, respectively, which is primarily related to the difference in basis of contributed property and accrued rental income.

Certain entities included in Boston Properties Limited Partnership’s consolidated financial statements are subject to certain state and local taxes. These taxes are recorded as operating expenses in the accompanying consolidated financial statements.

The following table reconciles GAAP net income attributable to Boston Properties Limited Partnership to taxable income (unaudited):



	For the year ended December 31,
	2017			2016			2015
	(in thousands)
Net income attributable to Boston Properties Limited Partnership	$	523,366		$	585,841		$	659,248
Straight-line rent and net “above-” and “below-market” rent adjustments	(86,773		)	(73,604		)	(103,227		)
Book/Tax differences from depreciation and amortization	144,436			245,239			329,629
Book/Tax differences from interest expense	(20,227		)	(40,481		)	(48,385		)
Book/Tax differences on gains/(losses) from capital transactions	784			(69,683		)	(67,602		)
Book/Tax differences from stock-based compensation	42,371			37,397			24,565
Tangible Property Regulations	(129,673		)	(117,102		)	(83,587		)
Other book/tax differences, net	37,607			(3,387		)	(14,561		)
Taxable income	$	511,891		$	564,220		$	696,080