Kodiak Sciences Inc. Notes to Consolidated Financial Statements (in thousands, except share and per share data) 112 Research and Development Expenses Costs related to research, design and development of products are charged to research and development expense as incurred. Research and development costs include, but are not limited to, payroll and personnel expenses, including stock- based compensation, laboratory supplies, outside services and allocated overhead, including rent, equipment, depreciation and utilities. Accrued Research and Development The Company has entered into various agreements with contract research organizations (“CROs”) and contract manufacturing organizations (“CMOs”). The Company’s research and development accruals are estimated based on the level of services performed, progress of the studies, including the phase or completion of events, and contracted costs. The estimated costs of research and development provided, but not yet invoiced, are included in accrued and other current liabilities on the consolidated balance sheets. If the actual timing of the performance of services or the level of effort varies from the original estimates, the Company will adjust the accrual accordingly. Payments made to CROs or CMOs under these arrangements in advance of the performance of the related services are recorded as prepaid expenses and other current assets until the services are rendered. Stock-Based Compensation The Company accounts for stock-based compensation in accordance with the provisions of Accounting Standards Codification (“ASC”) 718, Compensation-Stock Compensation, which requires stock-based compensation cost to be measured at grant date, based on the fair value of the award. The Company accounts for equity instruments issued to non-employees using a fair value approach. The fair value of stock options granted to non-employees is calculated at each grant date and remeasured at each reporting date using the Black-Scholes option pricing model. Fair Value of Common Stock Prior to the Company’s IPO, the fair value of the Company’s common stock was determined by the board of directors with assistance from management and external appraisers. Management’s approach to estimate the fair value of the Company’s common stock was consistent with the methods outlined in the American Institute of Certified Public Accountants’ Practice Aid, Valuation of Privately-Held-Company Equity Securities Issued as Compensation (“Practice Aid”). Management considered several factors to estimate enterprise value, including significant milestones that would generally contribute to increases in the value of the common stock. Subsequent to the Company’s IPO, the fair value of the Company’s common stock is determined based on its closing market price. Income Taxes The Company accounts for income taxes under the asset and liability method, which requires, among other things, that deferred income taxes be provided for temporary differences between the tax basis of the Company’s assets and liabilities and their financial statement reported amounts. In addition, deferred tax assets are recorded for the future benefit of utilizing net operating losses (“NOLs”) and research and development credit carryforwards and are measured using the enacted tax rates and laws that will be in effect when such items are expected to reverse. A valuation allowance is provided against deferred tax assets unless it is more likely than not that they will be realized. The Company accounts for uncertain tax positions by assessing all material positions taken in any assessment or challenge by relevant taxing authorities. Assessing an uncertain tax position begins with the initial determination of the position’s sustainability and is measured at the largest amount of benefit that is greater than fifty percent likely of being realized upon ultimate settlement. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of income tax expense or benefit. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits. Comprehensive Income (Loss) Comprehensive income (loss) is defined as a change in equity of a business enterprise during a period, resulting from transactions from non-owner sources. There have been no items qualifying as other comprehensive income (loss) and, therefore, for all periods presented, the Company’s comprehensive loss was the same as its reported net loss.