Use of Estimates

The preparation of financial statements in conformity with GAAP in the United States requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosures. On an ongoing basis, management evaluates its estimates including, but not limited to, those related to revenue recognition, revenue recognized under the units-of-revenue method, royalty and commercial payment receivables,

intangible assets, legal contingencies, contingent consideration, accrued expenses and stock-based compensation. The Company bases its estimates on historical experience and on various other market-specific and other relevant assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources.

Actual results may differ significantly from these estimates, such as the Company’s amortization of the payments received from HCRP. Under the contracts with HCRP, the amortization for the reporting period is calculated based on the payments expected to be made by the licensees to HCRP over the term of the arrangement. Any changes to the estimated payments by the licensees to HCRP can result in a material adjustment to revenue previously reported.

Revenue Recognition

The Company recognizes revenue from all contracts with customers according to ASC 606, except for contracts that are within the scope of other standards, such as leases, insurance and financial instruments. The Company recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the Company 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 obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract on whether each promised good or service is distinct to determine those that are performance obligations. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation based on relative fair values, when (or as) the performance obligation is satisfied.

The Company recognizes revenue from its license and collaboration arrangements and royalties. The terms of the arrangements generally include payment to the Company of one or more of the following: non-refundable, upfront license fees, development, regulatory and commercial milestone payments, and royalties on net sales of licensed products.

License of intellectual property

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 revenue from non-refundable, upfront fees allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. For licenses that are bundled with other promises, such as transfer of related materials, process and know-how, the Company utilizes judgement 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. Under the Company’s license agreements, the nature of the combined performance obligation is the granting of licenses to the customers as the other promises are not separately identifiable in the context of the arrangement. Since the Company grants the license to a customer as it exists at the point of transfer and is not involved in any future development or commercialization of the products related to the license, the nature of the license is a right to use the Company’s intellectual property as transferred. As such, the Company recognizes revenue related to the combined performance obligation upon completion of the delivery of the related materials, process and know-how (i.e., at a point in time).

Milestone payments

At the inception of each arrangement that includes development and regulatory milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price. ASC 606 suggests two alternatives to use when estimating the amount of variable consideration: the expected value method and the most likely amount method. Under the expected value method, an entity considers the sum of probability-weighted amounts in a range of possible consideration amounts. Under the most likely amount method, an entity considers the single most likely amount in a range of possible consideration amounts. The Company uses the most likely amount method for development and regulatory milestone payments.

If it is probable that a significant cumulative 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. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis. The Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company re-evaluates the probability or achievement of each such milestone and any related constraint, and if necessary, adjusts its estimates of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenue and earnings in the period of adjustment.

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).

Upfront payments and fees are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until the Company performs its obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional. 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 customer and the transfer of the promised goods or services to the customer will be one year or less.

Stock-Based Compensation

The Company recognizes compensation expense for all stock-based payment awards made to the Company’s employees, consultants and directors that are expected to vest based on estimated fair values. The valuation of stock option awards is determined at the date of grant using the Black-Scholes Model. The Black-Scholes Model requires inputs such

as the expected term of the option, expected volatility and risk-free interest rate. To establish an estimate of expected term, the Company considers the vesting period and contractual period of the award and its historical experience of stock option exercises, post-vesting cancellations and volatility. The estimate of expected volatility is based on the Company’s historical volatility. The risk-free rate is based on the yield available on United States Treasury zero-coupon issues corresponding to the expected term of the award. The Company records forfeitures when they occur. The Company records compensation expense for service-based awards on a straight-line basis over the requisite service period, which is generally the vesting period of the award, or to the date on which retirement eligibility is achieved, if shorter.

The grant date fair value of PSUs with market conditions are determined using the Monte Carlo valuation model. The Company records compensation expenses for PSUs based on graded expense attribution over the requisite service periods.

Purchase of Rights to Future Milestones, Royalties and Commercial Payments

The Company has purchased rights to receive a portion of certain future developmental, regulatory and commercial sales milestones, royalties and option fees on sales of products currently in clinical development or recently commercialized. The Company acquired such rights from various entities and recorded the amount paid for these rights as long-term royalty receivables (Note 5). In addition, the Company may be obligated to make contingent payments related to certain product development milestones, fees upon exercise of options related to future license products and sales-based milestones. The contingent payments are evaluated to determine if they are freestanding instruments or embedded derivatives. If the contingent payments fall within the scope of ASC 815, the contingent payments are measured at fair value at the inception of the arrangement, and subject to remeasurement to fair value each reporting period. Any changes in the estimated fair value are recorded in the condensed consolidated statement of operations and comprehensive loss. Contingent consideration payments that do not fall within the scope of ASC 815 are recognized when the amount is probable and estimable according to ASC 450.

The Company accounts for milestone and royalty rights related to developmental pipeline or recently commercialized products on a non-accrual basis using the cost recovery method. These developmental pipeline products are non-commercialized, non-approved products that require FDA or other regulatory approval, and thus have uncertain cash flows. The recently commercialized products do not have an established reliable sales pattern, and thus have uncertain cash flows. The Company is not yet able to reliably forecast future cash flows given their stages of development and commercialization. The related receivable balance is classified as noncurrent or current based on whether payments are probable and reasonably estimable to be received in the near term. Under the cost recovery method, any milestone or royalty payment received is recorded as a direct reduction of the recorded receivable balance. When the recorded receivable balance has been fully collected, any additional amounts collected are recognized as revenue.

Asset Acquisitions

As a first step, for each acquisition, the Company determines if it is an acquisition of a business or an asset acquisition under ASC 805. Acquisitions of assets or a group of assets that do not meet the definition of a business are accounted for as asset acquisitions under ASC 805-50, using the cost accumulation method, whereby the cost of the acquisition, including certain transaction costs, is allocated to the assets acquired on the basis of relative fair values (Note 4).

Contingent payments are evaluated whether they are freestanding instruments or embedded derivatives. If the contingent payments fall within the scope of ASC 815, the contingent payments are measured at fair value at the acquisition date, and subject to remeasurement to fair value each reporting period. The estimated fair value at the acquisition date is included in the cost of the acquired assets. Any subsequent changes in the estimated fair value are recorded in the condensed consolidated statement of operations and comprehensive loss. Contingent consideration payments that do not fall within the scope of ASC 815 are recognized when the amount is probable and estimable according to ASC 450.

Cash payments related to acquired assets are reflected as an investing cash flow in the Company’s condensed consolidated statement of cash flows.

Leases

The Company leases its headquarters office space in Emeryville, California.

The Company determines the initial classification and measurement of its right-of-use assets and lease liabilities at the lease commencement date and thereafter if modified. The lease term includes any renewal options and termination options that the Company is reasonably certain to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its incremental borrowing rate. The incremental borrowing rate is determined by using the rate of interest that the Company would pay to borrow on a collateralized basis an amount equal to the lease payments for a similar term and in a similar economic environment. The Company built its incremental borrowing rate starting with the interest rate on its fully collateralized debt and then adjusted it for lease term length.

Rent expense for the operating lease is recognized on a straight-line basis, over the reasonably assured lease term based on the total lease payments and is included in operating expenses in the condensed consolidated statements of operations and comprehensive loss.

The Company has elected the practical expedient to not separate lease and non-lease components. The Company’s non-lease components are primarily related to property maintenance, which varies based on future outcomes, and thus are recognized in rent expense when incurred.

The Company has also elected not to record on the consolidated balance sheet a lease which term is 12 months or less and does not include a purchase option that the Company is reasonably certain to exercise.

Net Loss per Share Attributable to Common Stockholders

The Company calculates basic and diluted loss per share attributable to common stockholders using the two-class method. The Company’s convertible Series X preferred stocks participate in any dividends declared by the Company on its common stock and are therefore considered to be participating securities. The Company’s Series A and Series B Preferred Stock do not participate in any dividends or distribution by the Company on its common stock and are therefore not considered to be participating securities.

Under the two-class method, net income, as adjusted for any accumulated dividends on Series A and Series B Preferred Stock for the period, is allocated to each class of common stock and participating security as if all of the net income for the period had been distributed. Undistributed earnings allocated to participating securities are subtracted from net income in determining net income attributable to common stockholders. During periods of loss, the Company allocates no loss to participating securities because they have no contractual obligation to share in the losses of the Company. Basic net loss per share attributable to common stockholders is then calculated by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding during the period. All participating securities are excluded from the basic weighted average common shares outstanding.

Diluted net loss per share attributable to common stockholders is based on the weighted average number of shares outstanding during the period, adjusted to include the assumed exercise of certain stock options and warrants for common stock using the treasury method, if dilutive. The calculation assumes that any proceeds that could be obtained upon exercise of options and warrants would be used to purchase common stock at the average market price during the period. Adjustments to the denominator are required to reflect the related dilutive shares. The Company’s Series A and Series B Preferred Stock become convertible upon the occurrence of specific events other than a change in the Company’s share price and, therefore, are not included in the diluted shares until the contingency is resolved.

Comprehensive Loss

Comprehensive loss is comprised of two components: net loss and other comprehensive loss. Other comprehensive loss refers to gains and losses that under U.S. GAAP are recorded as an element of stockholders’ equity but are excluded from net loss. The Company did not record any transactions within other comprehensive loss in the periods presented and, therefore, the net loss and comprehensive loss were the same for all periods presented.