The Company’s revenues are generated primarily through collaborative research, development and commercialization agreements. The terms of these agreements generally contain multiple promised goods and services, which may include (i) licenses, or options to obtain licenses, to the Company’s technology, (ii) research and development activities to be performed on behalf of the collaborative partner, and (iii) in certain cases, services in connection with the manufacturing of preclinical and clinical material. Payments to the Company under these arrangements typically include one or more of the following: non-refundable, upfront license fees; option exercise fees; funding of research and/or development efforts; milestone payments; and royalties on future product sales.

Collaboration Arrangements Within the Scope of ASC 808, Collaborative Arrangements

The Company analyzes its collaboration arrangements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and are therefore within the scope of Accounting Standards Codification (“ASC”) Topic 808, Collaborative Arrangements (“ASC 808”). This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements that are deemed to be within the scope of ASC 808, the Company first determines which elements of the collaboration are deemed to be within the scope of ASC 808 and those that are more reflective of a vendor-customer relationship and therefore within the scope of ASC 606, Revenue from Contracts with Customers (“ASC 606”). The Company’s policy is generally to recognize amounts received from collaborators in connection with joint operating activities that are within the scope of ASC 808 as a reduction in research and development expense.

Effective January 1, 2018, the Company adopted ASC 606 using the modified retrospective transition method. Under this method, the Company has recognized the cumulative effect of the adoption as an adjustment to the opening balance of accumulated deficit in the prior year condensed consolidated balance sheet. Financial results for the year ended December 31, 2018 and thereafter are presented under ASC 606. The provisions of ASC 606 apply to all contracts with customers, except for contracts that are within the scope of other standards, such as collaboration arrangements and leases.

Under ASC 606, the Company recognizes revenue when its customers obtain control of promised goods or services, in an amount that reflects the consideration which the Company determines it expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that the Company determines are within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligation(s) in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligation(s) in the contract; and (v) recognize revenue when (or as) the Company satisfies its performance obligation(s). As part of the accounting for these arrangements, the Company must make significant judgments, including identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each performance obligation.

Once a contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within the contract and determines those that are performance obligations. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The exercise of a material right is accounted for as a contract modification for accounting purposes.

The Company assesses whether each promised good or service is distinct for the purpose of identifying the performance obligations in the contract. This assessment involves subjective determinations and requires management to make judgments about the individual promised goods or services and whether such are separable from the other aspects of the contractual relationship. Promised goods and services are considered distinct provided that: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer (that is, the good or service is capable of being distinct) and (ii) the entity’s promise to transfer the good or service to the customer is separately identifiable from other promises in the contract (that is, the promise to transfer the good or service is distinct within the context of the contract). In assessing whether a promised good or service is distinct, the Company considers factors such as the research, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, an entity is required to combine that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct.

The transaction price is then determined and allocated to the identified performance obligations in proportion to their standalone selling prices (“SSP”) on a relative SSP basis. SSP is determined at contract inception and is not updated to reflect changes between contract inception and when the performance obligations are satisfied. Determining the SSP for performance obligations requires significant judgment. In developing the SSP for a performance obligation, the Company considers applicable market conditions and relevant entity-specific factors, including factors that were contemplated in negotiating the agreement with the customer and estimated costs. The Company validates the SSP for performance obligations by evaluating whether changes in the key assumptions used to determine the SSP will have a significant effect on the allocation of arrangement consideration between multiple performance obligations.

If the consideration promised in a contract includes a variable amount, the Company estimates the amount of consideration to which it will be entitled in exchange for transferring the promised goods or services to a customer. The Company determines the amount of variable consideration by using the expected value method or the most likely amount method. The Company includes the unconstrained amount of estimated variable consideration in the transaction price. The amount included in the transaction price is constrained to the amount for which it is probable that a significant reversal of cumulative revenue recognized will not occur. At the end of each subsequent reporting period, the Company re-evaluates the estimated variable consideration included in the transaction price and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis in the period of adjustment.

In determining the transaction price, the Company adjusts consideration for the effects of the time value of money if the timing of payments provides the Company with a significant benefit of financing. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the licensees and the transfer of the promised goods or services to the licensees will be one year or less. The Company assessed each of its revenue generating arrangements in order to determine whether a significant financing component exists and concluded that a significant financing component does not exist in any of its arrangements.

The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied at a point in time or over time, and if over time based on the use of an output or input method.

Licenses of intellectual property: The terms of the Company’s license agreements include the license of functional intellectual property, given the functionality of the intellectual property is not expected to change substantially as a result of the Company’s ongoing activities. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenues from the portion of the transaction price allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises (that is, for licenses that are not distinct from other promised goods and services in an arrangement), the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

Research and development funding: Arrangements that include payment for research and development services are generally considered to have variable consideration. If and when the Company assesses the payment for these services is no longer subject to the constraint on variable consideration, the related revenue is included in the transaction price.

Milestone payments: At the inception of each arrangement that includes non-refundable payments for contingent milestones, including preclinical research and development, clinical development and regulatory, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At the end of each reporting period, the Company re-evaluates the probability of the achievement of contingent milestones and the likelihood of a significant reversal of such milestone revenue, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect collaboration and licensing revenue in the period of adjustment. This quarterly assessment may result in the recognition of revenue related to a contingent milestone payment before the milestone event has been achieved.

Royalties: For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied).

The following table summarizes the total revenues earned in the three months ended March 31, 2019 and 2018, respectively, by partner (in thousands). Refer to Note 4, “Collaborations and License Agreements” regarding specific details.

Research and development expenses are charged to expense as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including internal costs for salaries, bonuses, benefits, stock-based compensation, facilities, and research-related overhead, and external costs for clinical trials, drug manufacturing and distribution, license fees, consultants and other contracted services.

In May 2016, the Company issued warrants to purchase an aggregate of 17,642,482 shares of common stock in connection with a private placement financing and recorded the warrants as a liability (the “PIPE Warrants”). The Company accounts for warrant instruments that either conditionally or unconditionally obligate the issuer to transfer assets as liabilities regardless of the timing of the redemption feature or price, even though the underlying shares may be classified as permanent or temporary equity. As of March 31, 2019, PIPE Warrants exercisable for 803,108 shares of common stock had been exercised, for approximately $0.8 million in cash proceeds, and PIPE Warrants exercisable for 16,839,375 shares of common stock were outstanding. Refer to Note 7, “Common Stock—Private Placement / PIPE Warrants” for further discussion of the private placement financing.

The PIPE Warrants contain a provision giving the warrant holder the option to receive cash, equal to the fair value of the remaining unexercised portion of the warrant, as cash settlement in the event that there is a fundamental transaction (contractually defined to include various merger, acquisition or stock transfer activities). Due to this provision, ASC 480, Distinguishing Liabilities from Equity requires that these warrants be classified as a liability and not as equity. Accordingly, the Company recorded a warrant liability in the amount of approximately $9.3 million upon issuance of the PIPE Warrants. The fair value of these warrants has been determined using the Black-Scholes pricing model. These warrants are subject to revaluation at each balance sheet date and any changes in fair value are recorded as a non-cash gain or (loss) in the Statement of Operations as a component of other income (expense), net until the earlier of their exercise or expiration or upon the completion of a liquidation event. Upon exercise, the PIPE Warrants are subject to revaluation just prior to the date of the warrant exercise and any changes in fair value are recorded as a non-cash gain or (loss) in the Statement of Operations as a component of other income (expense), net and the corresponding reduction in the PIPE Warrant liability is recorded as additional paid-in capital in the Balance Sheet as a component of stockholder’s equity.

The Company recorded a non-cash gain of approximately $8.8 million and a non-cash loss of approximately $1.5 million in the three months ended March 31, 2019 and 2018, respectively, in its Statement of Operations attributable to the decrease and increase, respectively, in the fair value of the PIPE Warrant liability that resulted from a lower stock price as of March 31, 2019 and a higher stock price as of March 31, 2018, respectively, relative to prior periods. In the three months ended March 31, 2018, the Company recorded a reduction in the PIPE Warrant liability, with a corresponding increase to additional paid-in capital, of approximately $1.1 million attributable to PIPE Warrant exercises in the first quarter of 2018.

The following table rolls forward the fair value of the Company’s PIPE Warrant liability, the fair value of which is determined by Level 3 inputs for the three months ended March 31, 2019 (in thousands):

Fair value at January 1, 2019	$	16,674
Decrease in fair value		(8,815	)
Fair value at March 31, 2019	$	7,859

The key assumptions used to value the PIPE Warrants were as follows:

	Issuance			December 31, 2018			March 31, 2019
Expected price volatility		76.25	%		82.64	%		111.99	%
Expected term (in years)		5.00			2.50			2.25
Risk-free interest rates		1.22	%		2.47	%		2.27	%
Stock price	$	0.89		$	1.60		$	0.82
Dividend yield		—			—			—

In December 2017, the Company entered into a binding memorandum of understanding (the “MOU”) with class representatives Bob Levine and William Windham (the “Plaintiffs”), regarding the settlement of a securities class action lawsuit (the “2013 Class Action”) that had been filed in 2013 and was pending in the United States District Court for the District of Massachusetts (the “District Court”) against the Company and certain of the Company’s former officers (Tuan Ha-Ngoc, David Johnston, and William Slichenmyer, together, the “Individual Defendants”), In re AVEO Pharmaceuticals, Inc. Securities Litigation et al., No. 1:13-cv-11157-DJC. As previously disclosed, the 2013 Class Action was purportedly brought on behalf of stockholders who purchased the Company’s common stock between May 16, 2012 and May 1, 2013 (the “Class”).

In December 2017, upon entering into the MOU, the Company’s liability related to this settlement became estimable and probable. Accordingly, the Company recorded an estimated $17.1 million contingent liability, including $15.0 million for the cash portion of the settlement with a corresponding insurance recovery for the 100% portion to be paid directly by certain of the Company’s insurance carriers, and an approximate $2.1 million estimate for the fair value on December 31, 2017 of 2.0 million warrants to purchase shares of its common stock that the Company agreed to issue the Class (the “Settlement Warrants”), with a corresponding non-cash charge to the Statement of Operations as a component of operating expense. The Settlement Warrants are exercisable for a one-year period from their date of issue at an exercise price equal to the closing price on December 22, 2017, the trading day prior to the execution of the MOU, which was $3.00 per share.

In January 2018, the Company entered into a definitive stipulation of settlement agreement (the “Stipulation”). In February 2018, the District Court preliminarily approved the Stipulation, following which the insurance carriers funded the settlement escrow account related to the $15.0 million cash portion of the settlement. On May 30, 2018, the District Court approved the Stipulation in its order of final approval and final judgment (the “Final Judgment”). Upon the conclusion of a 30-day appeal period, the Effective Date was deemed to be June 29, 2018. Pursuant to the Final Judgment, all claims against the Company were released upon the Effective Date. In addition, pursuant to the Stipulation, the Company had no interest in the settlement escrow account subsequent to the Effective Date. Accordingly, the $15 million contingent liability associated with the cash portion of the settlement and the corresponding insurance recovery was eliminated on the Effective Date. The Company had agreed to use its best efforts to issue and deliver the Settlement Warrants within ten business days following the Effective Date. On July 16, 2018, the Company issued and delivered the Settlement Warrants in accordance with the Stipulation and filed a corresponding shelf registration statement, File No. (333-226190) to register the shares of common stock underlying the Settlement Warrants which was declared effective by the SEC on July 25, 2018.

Refer to Note 9, “Legal Proceedings” for further discussion of the 2013 Class Action settlement.

The estimated fair value of the Settlement Warrants was determined using the Black-Scholes pricing model. The estimated fair value of the Settlement Warrants was subject to revaluation at each balance sheet date and any changes in fair value were recorded as a non-cash gain or (loss) in the Statement of Operations as a component of operating expenses until the Settlement Warrants were issued. The Company recorded a non-cash loss of approximately $42,000 in the three months ended March 31, 2018 in its Statement of Operations attributable to the increase in the fair value of the Settlement Warrants that principally resulted from a higher stock price as of March 31, 2018, relative to prior periods. In addition, the fair value of the Settlement Warrants on June 30, 2018 was determined based on the estimated fair value of the Settlement Warrants at the time of issuance. The Company recorded non-cash gains of approximately $0.7 million in each of the three months and six months ended June 30, 2018, respectively, in its Statement of Operations attributable to the decrease in the fair value of the Settlement Warrants that principally resulted from a lower volatility rate relative to prior periods.

In July 2018, upon the issuance of the Settlement Warrants, the Company reclassified the approximate $1.4 million value of the Settlement Warrants from a liability to stockholders equity as a component of additional paid-in-capital based upon the terms of the warrant agreement and, accordingly, the approximate $1.4 million contingent liability on the Company’s balance sheet associated with the warrant portion of the settlement was eliminated.

The key assumptions used to estimate the fair value the Settlement Warrants were as follows:

	December 31, 2017			March 31, 2018			June 30, 2018
Expected price volatility		101.52	%		96.01	%		62.74	%
Expected term (in years)		1.00			1.00			1.00
Risk-free interest rates		1.76	%		2.09	%		2.37	%
Stock price	$	2.79		$	2.90		$	2.90
Dividend yield		—			—			—

The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase and an investment in a U.S. government money market fund to be cash equivalents. Changes in the balance of cash and cash equivalents may be affected by changes in investment portfolio maturities, as well as actual cash disbursements to fund operations.

The Company’s cash is deposited in highly-rated financial institutions in the United States. The Company invests in U.S. government money market funds, high-grade, short-term commercial paper, corporate bonds and other U.S. government agency securities, which management believes are subject to minimal credit and market risk. The carrying values of the Company’s cash and cash equivalents approximate fair value due to their short-term maturities.

Marketable securities consist primarily of investments which have expected average maturity dates in excess of three months, but not longer than 24 months. The Company invests in high-grade corporate obligations, including commercial paper, and U.S. government and government agency obligations that are classified as available-for-sale.

The Company did not have any marketable securities as of March 31, 2019 or December 31, 2018, other than those classified as cash equivalents.

Marketable securities, including those classified as cash equivalents, are stated at fair value, including accrued interest, with their unrealized gains and losses included as a component of accumulated other comprehensive income or loss, which is a separate component of stockholders’ deficit. The fair value of these securities is based on quoted prices and observable inputs on a recurring basis. The cost of marketable securities, including those classified as cash equivalents, is adjusted for amortization of premiums and accretion of discounts to maturity, with such amortization and accretion recorded as a component of interest expense, net. Realized gains and losses are determined on the specific identification method. Unrealized gains and losses are included in other comprehensive loss until realized, at which point they would be recorded as a component of interest expense, net.

Below is a summary of cash, cash equivalents and marketable securities at March 31, 2019 and December 31, 2018 (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
March 31, 2019
Cash and cash equivalents:
Cash and money market funds	$	14,806	$	—	$	—	$	14,806
Corporate debt securities		8,677		—		—		8,677
Total cash, cash equivalents and marketable securities	$	23,483	$	—	$	—	$	23,483

December 31, 2018:
Cash and cash equivalents:
Cash and money market funds	$	16,211	$	—	$	—	$	16,211
Corporate debt securities		8,215		1		—		8,216
Total cash, cash equivalents and marketable securities	$	24,426	$	1	$	—	$	24,427

Financial instruments that potentially subject the Company to credit risk primarily consist of cash and cash equivalents, marketable securities and accounts receivable. The Company maintains deposits in highly-rated, federally-insured financial institutions in excess of federally insured limits. The Company’s investment strategy is focused on capital preservation. The Company invests in instruments that meet the high credit quality standards outlined in the Company’s investment policy. This policy also limits the amount of credit exposure to any one issue or type of instrument.

The Company’s accounts receivable primarily consists of amounts due to the Company from licensees and collaborators. The Company has not experienced any material losses related to accounts receivable from individual licensees or collaborators.

The fair value of the Company’s financial assets and liabilities reflects the Company’s estimate of amounts that it would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from sources independent from the Company) and to minimize the use of unobservable inputs (the Company’s assumptions about how market participants would price assets and liabilities). The following fair value hierarchy is used to classify assets and liabilities based on the observable inputs and unobservable inputs used in order to value the assets and liabilities:

Financial assets and liabilities are classified in their entirety within the fair value hierarchy based on the lowest level of input that is significant to the fair value measurement. The Company measures the fair value of its marketable securities by taking into consideration valuations obtained from third-party pricing sources. The pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker-dealer quotes on the same or similar securities, issuer credit spreads, benchmark securities and other observable inputs.

As of March 31, 2019, the Company’s financial assets valued based on Level 1 inputs consisted of cash and cash equivalents in a U.S. government money market fund and its financial assets valued based on Level 2 inputs consisted of high-grade corporate debt securities, including commercial paper. During the three months ended March 31, 2019, the Company did not have any transfers of financial assets between Levels 1 and 2.

As of March 31, 2019, the Company’s financial liability that was recorded at fair value consisted of the PIPE Warrant liability.

The fair value of the Company’s loans payable at March 31, 2019 approximates its carrying value, computed pursuant to a discounted cash flow technique using a market interest rate and is considered a Level 3 fair value measurement. The effective interest rate, which reflects the current market rate, considers the fair value of the warrants issued in connection with the loan, loan issuance costs and the deferred financing charge.

The following table summarizes the assets and liabilities measured at fair value on a recurring basis at March 31, 2019 and December 31, 2018 (in thousands):

	Fair Value Measurements as of March 31, 2019
	Level 1		Level 2		Level 3		Total
Financial assets carried at fair value:
Cash and money market funds	$	14,806	$	—	$	—	$	14,806
Corporate debt securities		—		8,677		—		8,677
Total cash, cash equivalents and marketable securities	$	14,806	$	8,677	$	—	$	23,483
Financial liabilities carried at fair value:
Total PIPE Warrant liability	$	—	$	—	$	7,859	$	7,859

	Fair Value Measurements as of December 31, 2018
	Level 1		Level 2		Level 3		Total
Financial assets carried at fair value:
Cash and money market funds	$	16,211	$	—	$	—	$	16,211
Corporate debt securities		—		8,216		—		8,216
Total cash, cash equivalents and marketable securities	$	16,211	$	8,216	$	—	$	24,427
Financial liabilities carried at fair value:
Total PIPE Warrant liability	$	—	$	—	$	16,674	$	16,674

Basic net income (loss) per share attributable to AVEO common stockholders is based on the weighted-average number of common shares outstanding during the period. Diluted net income (loss) per share attributable to AVEO common stockholders is based on the weighted-average number of common shares outstanding during the period plus additional weighted-average common equivalent shares outstanding during the period when the effect is dilutive. For the three months ended March 31, 2019, common equivalent shares include the incremental common shares issuable upon the exercise of the PIPE Warrants, as determined using the treasury stock method, and exclude the incremental common shares issuable upon the exercise of stock options and the Settlement Warrants as their effect would be anti-dilutive. For the three months ended March 31, 2018, diluted net loss per share is the same as basic net loss per share as the inclusion of weighted-average shares of common stock issuable upon the exercise of stock options and warrants would be anti-dilutive.

The following table summarizes the computation of basic and diluted net income (loss) per share for the three months ended March 31, 2019 and 2018, respectively (in thousands except per share amounts):

	Three Months Ended March 31,
	2019			2018
Basic net income (loss) attributable to AVEO common stockholders	$	555		$	(8,988	)
Less: non-cash gains attributable to the change in fair value of the PIPE Warrant liability		(8,815	)		—
Diluted net income (loss) attributable to AVEO common stockholders	$	(8,260	)	$	(8,988	)

Weighted-average shares of common stock outstanding		132,304			118,840

Dilutive securities:
Incremental common shares issuable upon the exercise of the PIPE Warrants		527			—
Weighted-average number of common shares outstanding and dilutive share equivalents outstanding		132,831			118,840
Basic net income (loss) per share	$	0.01		$	(0.08	)
Diluted net income (loss) per share	$	(0.06	)	$	(0.08	)

The following table summarizes outstanding securities not included in the computation of diluted net loss per common share as the effect would have been anti-dilutive for the three months ended March 31, 2019 and 2018, respectively (in thousands):

	Outstanding at March 31,
	2019		2018
Options outstanding		10,190		10,029
PIPE Warrants outstanding		—		16,865
Settlement Warrants outstanding		2,000		—
Total		12,190		26,894

Under the Company’s stock-based compensation programs, the Company periodically grants stock options and restricted stock to employees, directors and nonemployee consultants. The Company also issues shares under an employee stock purchase plan. The fair value of all awards is recognized in the Company’s statements of operations over the requisite service period for each award.

Awards that vest as the recipient provides service are expensed on a straight-line basis over the requisite service period. Other awards, such as performance-based awards that vest upon the achievement of specified goals, are expensed using the accelerated attribution method if achievement of the specified goals is considered probable. The Company has also granted awards that vest upon the achievement of market conditions. Per ASC 718, Share-Based Payments, market conditions must be considered in determining the estimated grant-date fair value of share-based payments and the market conditions must be considered in determining the requisite service period over which compensation cost is recognized. The Company estimates the fair value of the awards with market conditions using a Monte Carlo simulation, which utilizes several assumptions including the risk-free interest rate, the volatility of the Company’s stock and the exercise behavior of award recipients. The grant-date fair value of the awards is then recognized over the requisite service period, which represents the derived service period for the awards as determined by the Monte Carlo simulation.

The Company uses the Black-Scholes option pricing model to value its stock option awards without market conditions, which require the Company to make certain assumptions regarding the expected volatility of its common stock price, the expected term of the option grants, the risk-free interest rate and the dividend yield with respect to its common stock. The Company calculates volatility using its historical stock price data. Due to the lack of the Company’s own historical data, the Company elected to use the “simplified” method for “plain vanilla” options to estimate the expected term of the Company’s stock option grants. Under this approach, the weighted-average expected life is presumed to be the average of the vesting term and the contractual term of the option. The risk-free interest rate used for each grant is based on the U.S. Treasury yield curve in effect at the time of grant for instruments with a similar expected life. The Company utilizes a dividend yield of zero based on the fact that the Company has never paid cash dividends and has no present intention to pay cash dividends.

The fair value of equity-classified awards to employees and directors are measured at fair value on the date the awards are granted. During the three months ended March 31, 2019 and 2018, the Company recorded the following stock-based compensation expense (in thousands):

The Company provides for income taxes using the asset-liability method. Under this method, deferred tax assets and liabilities are recognized based on differences between financial reporting and tax bases of assets and liabilities, and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The Company calculates its provision for income taxes on ordinary income based on its projected annual tax rate for the year. Uncertain tax positions are recognized if the position is more-likely-than-not to be sustained upon examination by a tax authority. Unrecognized tax benefits represent tax positions for which reserves have been established. As of March 31, 2019, the Company is forecasting a net loss for the year ended December 31, 2019 and an effective tax rate of 0%. The Company maintains a full valuation allowance on all deferred tax assets.

Operating segments are defined as components of an enterprise engaging in business activities for which discrete financial information is available and regularly reviewed by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating segment principally in the United States. As of March 31, 2019, the Company has no net assets located outside of the United States.

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect certain reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, the assessment of the Company’s ability to continue as a going concern, and the reported amounts of revenues and expenses during the reporting periods. Significant items subject to such estimates and assumptions include revenue recognition, contract research accruals, measurement of the PIPE Warrant liability, estimated settlement liabilities, measurement of stock-based compensation, and estimates of the Company’s capital requirements over the next twelve months from the date of issuance of the interim condensed consolidated financial statements. The Company bases its estimates on historical experience and various other assumptions that management believes to be reasonable under the circumstances. Material changes in these estimates could occur in the future. Changes in estimates are recorded or reflected in the Company’s disclosures in the period in which they become known. Actual results could differ from those estimates if past experience or other assumptions do not turn out to be substantially accurate.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) (“ASU 2016-02”), which requires lessees to recognize a right-of-use (“ROU”) asset and lease liability for most lease arrangements. In July 2018, the FASB issued ASU 2018-10, Codification Improvement to Topic 842, Leases (“ASU 2018-10”) and ASU 2018-11, Leases (Topic 842), Targeted Improvements (“ASU 2018-11”). ASU 2018-10 made technical corrections to the new leases standard, clarifying certain inconsistencies in the guidance. ASU 2018-11 provides entities with a new transition method that allows them to use the effective date of the new leases standard as the date of initial application on transition. ASU 2016-02, as modified by ASU 2018-10 and ASU 2018-11 is effective for annual reporting periods beginning after December 15, 2018.

The Company adopted ASU 2016-02 effective January 1, 2019 using the required modified retrospective approach and utilizing the effective date as its date of initial application. As a result, prior periods are presented in accordance with the previous guidance in ASC 840, Leases (“ASC 840”). In connection with the adoption of ASU 2016-02, the Company elected the package of practical expedients permitted under the transition guidance within the new standard, which does not require the reassessment of the following: i) whether existing or expired arrangements are or contain a lease, ii) the lease classification of existing or expired leases, and iii) whether previous initial direct costs would qualify for capitalization under the new lease standard. The Company made an accounting policy election not to recognize ROU assets or related lease liabilities with a lease term of twelve months or less in its Consolidated Balance Sheet. Such short-term lease payments are recorded in its Statement of Operations in the period in which the obligation for those payments was incurred.

As of the date of initial application of ASU 2016-02 and as of March 31, 2019, all of the Company’s lease obligations have lease terms that are less than twelve months. The Company’s lease arrangement for its office facility is cancellable within 30 days’ notice to its landlord and excludes any extension incentives or disincentives to renew for an extended period of time. In addition, the Company has drug storage arrangements with multiple storage providers that are cancellable at any time without penalty to the Company. In the three months ended March 31, 2019, the Company recognized approximately $0.2 million in short-term lease expense in its Statement of Operations.

In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting, which simplifies the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. The new standard is effective for annual reporting periods beginning after December 15, 2018 with early adoption permitted. The Company adopted the new standard effective January 1, 2019. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements.

In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments, (“ASU 2016-13”). This standard requires that for most financial assets, losses be based on an expected loss approach which includes estimates of losses over the life of exposure that considers historical, current and forecasted information. Expanded disclosures related to the methods used to estimate the losses as well as a specific disaggregation of balances for financial assets are also required. This standard is effective for annual periods beginning after December 15, 2019 and interim periods within those annual periods, with early adoption permitted for annual periods beginning after December 15, 2018. The Company is assessing the impact this standard will have on its consolidated financial statements

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement (“ASU 2018-13”), which modifies the disclosure requirements for fair value measurements. The new standard is effective for the Company on January 1, 2020. Early adoption is permitted. The Company currently is evaluating the impact the adoption of ASU 2018-13 may have on its disclosures.