Invitae (NVTAQ) 10-K 10 Mar 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Mar. 02, 2016	Jun. 30, 2015
Document and Entity Information
Entity Registrant Name	Invitae Corp
Entity Central Index Key	1,501,134
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Common Stock, Shares Outstanding		31,976,501
Entity Public Float			$ 180,700,000
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 73,238	$ 107,027
Marketable securities	53,780
Prepaid expenses and other current assets	4,292	2,616
Total current assets	131,310	109,643
Property and equipment, net	18,709	15,672
Restricted cash	4,831	150
Other assets	1,826	3,313
Total assets	156,676	128,778
Current liabilities:
Accounts payable	3,500	2,862
Accrued liabilities	4,253	3,237
Capital lease obligation, current portion	1,588	1,524
Debt, current portion	1,536
Total current liabilities	10,877	7,623
Capital lease obligation, net of current portion	1,576	2,011
Debt, net of current portion	5,504
Other long-term liabilities	343	415
Total liabilities	$ 18,300	$ 10,049
Commitments and contingencies (Note 5)
Convertible preferred stock, $0.0001 par value; 0 and 141,131,524 shares authorized, 0 and 141,131,524 shares issued and outstanding as of December 31, 2015 and December 31, 2014, respectively		$ 202,305
Stockholders' equity (deficit):
Preferred stock, $0.0001 par value; 20,000,000 and 0 shares authorized, no shares issued and outstanding as of December 31, 2015 and December 31, 2014
Common stock, $0.0001 par value; 400,000,000 and 160,131,524 shares authorized, 31,935,121 and 944,581 shares issued and outstanding as of December 31, 2015 and December 31, 2014, respectively	$ 4
Accumulated other comprehensive gain (loss)	(15)
Additional paid-in capital	313,349	$ 1,604
Accumulated deficit	(174,962)	(85,180)
Total Stockholders' equity (deficit)	138,376	(83,576)
Total liabilities, convertible preferred stock, and stockholders' equity (deficit)	$ 156,676	$ 128,778

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheets
Convertible preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized	0	141,131,524
Convertible preferred stock, shares issued	0	141,131,524
Convertible preferred stock, shares outstanding	0	141,131,524
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, authorized shares	20,000,000	0
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	400,000,000	160,131,524
Common stock, shares issued	31,935,121	944,581
Common stock, shares outstanding	31,935,121	944,581

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements of Operations
Revenue	$ 8,378	$ 1,604	$ 148
Costs and operating expenses:
Cost of revenue	16,523	5,624	667
Research and development	42,806	22,063	16,039
Selling and marketing	22,479	8,669	2,431
General and administrative	16,047	12,600	5,764
Total costs and operating expenses	97,855	48,956	24,901
Loss from operations	(89,477)	(47,352)	(24,753)
Other income (expense), net	(94)	(79)	(26)
Interest expense	(211)	(61)	(59)
Net loss	(89,782)	(47,492)	(24,838)
Net loss attributable to common stockholders	$ (89,782)	$ (47,492)	$ (24,989)
Net loss per share attributable to common stockholders, basic and diluted	$ (3.18)	$ (56.14)	$ (36.13)
Shares used in computing net loss per share attributable to common stockholders, basic and diluted	28,213,324	846,027	691,731

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements of Comprehensive Loss
Net loss	$ (89,782)	$ (47,492)	$ (24,838)
Other comprehensive loss:
Unrealized loss on available-for-sale marketable securities, net of tax	(15)
Comprehensive loss	$ (89,797)	$ (47,492)	$ (24,838)

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Common stock	Additional paid-in capital	Accumulated Other Comprehensive Income (Loss)	Accumulated deficit	Total
Balance at the beginning of the period at Dec. 31, 2012		$ 91		$ (12,850)	$ (12,759)
Balance at the beginning of the period (in shares) at Dec. 31, 2012	661,118
Increase (Decrease) in Stockholders' Deficit
Common stock issued on exercise of stock options		39			39
Common stock issued on exercise of stock options (in shares)	31,666
Vesting of common stock related to early exercise of options		18			18
Vesting of common stock related to early exercise of options (in shares)	39,886
Stock-based compensation expense		260			260
Net loss				(24,838)	(24,838)
Balance at the end of the period at Dec. 31, 2013		408		(37,688)	(37,280)
Balance at the end of the period (in shares) at Dec. 31, 2013	732,670
Increase (Decrease) in Stockholders' Deficit
Common stock issued on exercise of stock options		209			209
Common stock issued on exercise of stock options (in shares)	168,867
Vesting of common stock related to early exercise of options		16			16
Vesting of common stock related to early exercise of options (in shares)	43,044
Stock-based compensation expense		971			971
Net loss				(47,492)	(47,492)
Balance at the end of the period at Dec. 31, 2014		1,604		(85,180)	$ (83,576)
Balance at the end of the period (in shares) at Dec. 31, 2014	944,581				944,581
Increase (Decrease) in Stockholders' Deficit
Conversion of preferred stock into common stock upon initial public offering costs (in shares)	23,521,889
Conversion of preferred stock into common stock upon initial public offering costs	$ 3	202,302			$ 202,305
Issuance of common stock in connection with initial public offering, net of offering costs (in shares)	7,302,500
Issuance of common stock in connection with initial public offering, net of offering costs	$ 1	105,667			105,668
Common stock issued on exercise of stock options		288			288
Common stock issued on exercise of stock options (in shares)	148,870
Vesting of common stock related to early exercise of options		11			11
Vesting of common stock related to early exercise of options (in shares)	17,281
Stock-based compensation expense		3,477			3,477
Unrealized loss on investments			$ (15)		(15)
Net loss				(89,782)	(89,782)
Balance at the end of the period at Dec. 31, 2015	$ 4	$ 313,349	$ (15)	$ (174,962)	$ 138,376
Balance at the end of the period (in shares) at Dec. 31, 2015	31,935,121				31,935,121

Consolidated Statements of Con7

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity 2 (Deficit) - USD ($) $ in Thousands	Convertible preferred stock	Series D convertible preferred stock	Series E convertible preferred stock	Series F convertible preferred stock	Total
Balance at the beginning of the period at Dec. 31, 2012	$ 36,755
Balance at the beginning of the period (in shares) at Dec. 31, 2012	46,987,747
Increase (Decrease) in Convertible Preferred Stock
Issuance of convertible preferred stock, net of issuance costs		$ 9,933	$ 39,886
Balance at the end of the period at Dec. 31, 2013	$ 86,574
Balance at the end of the period (in shares) at Dec. 31, 2013	81,131,524
Increase (Decrease) in Convertible Preferred Stock
Issuance of convertible preferred stock, net of issuance costs (in shares)		8,000,000	26,143,777
Issuance of convertible preferred stock, net of issuance costs				$ 115,731
Balance at the end of the period at Dec. 31, 2014	$ 202,305				$ 202,305
Balance at the end of the period (in shares) at Dec. 31, 2014	141,131,524	8,000,000	26,143,777	60,000,000	141,131,524
Increase (Decrease) in Convertible Preferred Stock
Issuance of convertible preferred stock, net of issuance costs (in shares)		8,000,000	26,143,777	60,000,000	141,131,524
Conversion of preferred stock into common stock upon initial public offering costs (in shares)	(141,131,524)
Conversion of preferred stock into common stock upon initial public offering costs	$ (202,305)				$ 202,305
Balance at the end of the period (in shares) at Dec. 31, 2015					0
Increase (Decrease) in Convertible Preferred Stock
Issuance of convertible preferred stock, net of issuance costs (in shares)					0

Consolidated Statements of Con8

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Series C convertible preferred stock
Sale price on common stock (in dollars per share)	$ 0.95
Series D convertible preferred stock
Sale price on common stock (in dollars per share)	1.25	$ 1.25
Issuance costs		$ 67
Series E convertible preferred stock
Sale price on common stock (in dollars per share)	1.53	$ 1.53
Issuance costs		$ 114
Series F convertible preferred stock
Sale price on common stock (in dollars per share)	$ 2
Issuance costs	$ 4,268

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net loss	$ (89,782)	$ (47,492)	$ (24,838)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,321	2,315	928
Stock-based compensation	3,477	971	260
Amortization of premium on marketable securities	632
Loss on disposal of assets	23	37
Changes in operating assets and liabilities
Prepaid expenses and other current assets	(1,676)	(1,880)	(363)
Other assets	36	(849)	(4)
Accounts payable	508	2,072	220
Accrued expenses and other liabilities	806	2,386	767
Net cash used in operating activities	(80,655)	(42,440)	(23,030)
Cash flows from investing activities
Purchase of marketable securities	(216,994)
Proceeds from sales and maturities of marketable securities	162,567
Purchases of property and equipment	(6,464)	(6,686)	(4,520)
Change in restricted cash	(4,681)	(30)	(60)
Net cash used in investing activities	(65,572)	(6,716)	(4,580)
Cash flows from financing activities
Proceeds from issuance of convertible preferred stock, net of issuance costs		115,731	49,819
Proceeds from issuance of common stock upon initial public offering, net of issuance costs	107,120
Proceeds from exercise of stock options	288	209	67
Proceeds from loan agreement, net of financing costs	7,453
Loan payments	(413)
Capital lease principal payment	(2,010)	(1,376)	(1,007)
Payments for deferred offering costs		(1,451)
Net cash provided by financing activities	112,438	113,113	48,879
Net increase (decrease) in cash and cash equivalents	(33,789)	63,957	21,269
Cash and cash equivalents at beginning of period	107,027	43,070	21,801
Cash and cash equivalents at end of period	73,238	107,027	43,070
Supplemental cash flow information
Interest paid	211	61	56
Supplemental cash flow information of non-cash investing and financing activities:
Equipment acquired through capital leases	1,639	2,850	1,793
Conversion of preferred stock into common stock upon initial public offering costs	202,305
Change in purchases of property and equipment in accounts payable and accrued liabilities	$ 603	325	$ 49
Deferred offering costs included in accounts payable and accrued liabilities		$ 450

Organization and description of

Organization and description of business	12 Months Ended
	Dec. 31, 2015
Organization and description of business
Organization and description of business	1. Organization and description of business Invitae Corporation (the "Company") was incorporated in the state of Delaware on January 13, 2010, as Locus Development, Inc. and changed its name to Invitae Corporation in 2012. The Company utilizes an integrated portfolio of laboratory processes, software tools and informatics capabilities to process DNA-containing samples, analyze information about patient-specific genetic variation and generate test reports for clinicians and their patients. The Company's laboratory is located in San Francisco, California. The Company's current product is an assay of over 600 genes that can be used for multiple indications. The test includes multiple genes associated with hereditary cancer, neurological disorders, cardiovascular disorders and other hereditary conditions. The Company operates in one segment. Initial Public Offering In February 2015, the Company completed an initial public offering ("IPO") of its common stock. In connection with its IPO, the Company sold 7,302,500 shares of common stock at $16.00 per share for aggregate net proceeds of $105.7 million after underwriting discounts and commissions and offering expenses payable by the Company. This includes the exercise in full by the underwriters of their option to purchase up to 952,500 additional shares of common stock at the same price to cover over-allotments. Upon the closing of the IPO, all shares of convertible preferred stock then outstanding converted into 23,521,889 shares of common stock. Upon the effectiveness of the Amended and Restated Certificate of Incorporation of the Company on February 12, 2015, the number of shares of capital stock the Company is authorized to issue was increased to 420,000,000 shares, of which 400,000,000 shares are common stock and 20,000,000 shares are preferred stock. Both the common stock and preferred stock have a par value of $0.0001 per share. There are no shares of preferred stock outstanding at December 31, 2015.

Summary of significant accounti

Summary of significant accounting policies	12 Months Ended
	Dec. 31, 2015
Summary of significant accounting policies
Summary of significant accounting policies	2. Summary of significant accounting policies Principles of consolidation The Company's consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America ("U.S. GAAP"). The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Use of estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. The Company believes judgment is involved in determining revenue recognition; the recoverability of long-lived assets; the fair value of the Company's common stock prior to the IPO; stock-based compensation expense; and income tax uncertainties. The Company bases these estimates on historical and anticipated results, trends, and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. Actual results could differ materially from those estimates and assumptions. Concentrations of credit risk and other risks and uncertainties Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents. The Company's cash and cash equivalents are held by financial institutions in the United States and Chile. Such deposits may exceed federally insured limits. As of December 31, 2015, substantially all of the Company's revenue has been derived from sales of its assays. Significant customers are those which represent 10% or more of the Company's total revenue for each year presented on the statements of operations and comprehensive loss. For each significant customer, revenue as a percentage of total revenue are as follows: December 31, Customers 2015 2014 2013 Customer A * * % Customer B * % — Customer C % * * * Less than 10% of total revenue Cash equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. Cash equivalents consist primarily of amounts invested in money market funds and U.S government agency securities. Marketable securities All marketable securities have been classified as "available-for-sale" and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. Management determines the appropriate classification of its marketable securities in debt securities at the time of purchase and reevaluates such designation as of each balance sheet date. Short-term marketable securities have maturities less than 365 days as of the balance sheet date. Unrealized gains and losses are excluded from earnings and are reported as a component of other comprehensive income (loss). Realized gains and losses and declines in fair value judged to be other than temporary, if any, on available-for-sale securities are included in interest and other income (expense), net. The cost of securities sold is based on the specific-identification method. Interest on marketable securities is included in interest and other income (expense), net. Restricted cash Restricted cash consists of money market funds that serve as: collateral for a security deposit for the Company's lease agreement for a laboratory and headquarters entered into in September 2015; collateral for a credit card agreement at one of the Company's financial institutions; and for securing a letter of credit as collateral for the Company's Cambridge Massachusetts facility sublease agreement. Internal-use software The Company capitalizes third-party costs incurred in the application development stage to design and implement internal-use software. Maintenance and training costs relating to internal-use software are expensed as incurred. Capitalized internal-use software costs are recorded as property and equipment and are amortized over estimated useful lives of up to three years on a straight line basis. Amortization of capitalized internal-use software costs is recorded as sales and marketing expense. During the years ended December 31, 2015, 2014 and 2013, the Company capitalized $1.5 million, $550,000 and $250,000, respectively, of internal-use software development costs. Internal-use software amortization was $718,000, $152,000, and zero, in 2015, 2014 and 2013, respectively. The carrying value of capitalized internal-use software at December 31, 2015 and 2014 was $1.4 million and $648,000, respectively. The weighted average useful life of capitalized internal-use software at December 31, 2015 was 13 months. Deferred offering costs Deferred offering costs, which primarily consist of direct incremental legal, accounting and other fees relating to the IPO, were initially capitalized. As of December 31, 2014, the Company capitalized $1.9 million of deferred offering costs in other assets on the consolidated balance sheets. The deferred offering costs were subsequently offset against IPO proceeds upon the closing of the IPO in February 2015. Leases The Company rents its facilities under operating lease agreements and recognizes related rent expense on a straight-line basis over the term of the lease. Some of the lease agreements contain rent holidays, scheduled rent increases, lease incentives, and renewal options. Rent holidays and scheduled rent increases are included in the determination of rent expense to be recorded over the lease term. Lease incentives are recognized as a reduction of rent expense on a straight-line basis over the term of the lease. Renewals are not assumed in the determination of the lease term unless they are deemed to be reasonably assured at the inception of the lease. The Company recognizes rent expense beginning on the date it obtains the legal right to use and control the leased space. Property and equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, generally between three and seven years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life of the asset or the term of the lease. Amortization expense of assets acquired through capital leases is included in depreciation and amortization expense in the consolidated statements of operations and comprehensive loss. Maintenance and repairs are charged to expense as incurred, and improvements and betterments are capitalized. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet and any resulting gain or loss is reflected in the statements of operations and comprehensive loss in the period realized. The useful lives of the property and equipment are as follows: Furniture and fixtures 7 years Automobiles 7 years Laboratory equipment 5 years Computer equipment 3 years Software 3 years Leasehold improvements Shorter of lease term or estimated useful life Long-lived assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An impairment loss is recognized when the total estimated future undiscounted cash flows expected to result from the use of the asset and its eventual disposition are less than its carrying amount. Impairment, if any, would be assessed using discounted cash flows or other appropriate measures of fair value. The Company has not recorded an impairment of any long-lived assets during any of the periods presented. Fair value of financial instruments The Company's financial instruments consist principally of cash and cash equivalents, marketable securities, accounts payable, capital leases and debt relating to equipment financing. The carrying amounts of certain of these financial instruments, including cash and cash equivalents, and accounts payable, approximate fair value due to their short maturities. Based on borrowing rates available to us, the carrying value of capital leases approximates fair value. See Note 4, "Fair value measurements" for further information on the fair value of the Company's financial instruments. Revenue recognition Revenue is generated from the sale of tests that provide analysis and associated interpretation of the sequencing of parts of the genome. Revenue associated with subsequent re-requisition services was de minimis for all periods presented. Revenue is recognized when persuasive evidence of an arrangement exists; delivery has occurred or services have been rendered; the fee is fixed or determinable; and collectability is reasonably assured. The criterion for whether the fee is fixed or determinable and whether collectability is reasonably assured are based on management's judgments. When evaluating collectability, in situations where contracted reimbursement coverage does not exist, the Company considers whether the Company has sufficient history to reliably estimate a payer's individual payment patterns. The Company reviews the number of tests paid against the number of tests billed over at least several months of payment history and the payer's outstanding balance for unpaid tests to determine whether payments are being made at a consistently high percentage of tests billed and at appropriate amounts given the amount billed. For most payers, the Company has not been able to demonstrate a predictable pattern of collectability, and therefore recognizes revenue when payment is received. For payers who have demonstrated a consistent pattern of payment of tests billed at appropriate amounts, the Company recognizes revenue, at estimated realizable amounts, upon delivery of test results. Cost of revenue Cost of revenue reflects the aggregate costs incurred in delivering the genetic testing results to clinicians and includes expenses for personnel costs including stock-based compensation, materials and supplies, equipment and infrastructure expenses associated with testing and allocated overhead including rent, equipment depreciation and utilities. Costs associated with performing the Company's test are recorded as the test is processed regardless of whether and when revenue is recognized with respect to that test. Research and development Research and development costs are charged to operations as incurred. Research and development costs include, but are not limited to, payroll and personnel- related expenses, stock-based compensation expense, reagents and laboratory supplies, consulting costs, and allocated overhead including rent, information technology, equipment depreciation and utilities. Income taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the 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. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Stock-based compensation The Company measures its stock-based payment awards made to employees and directors based on the estimated fair values of the awards and recognizes the compensation expense over the requisite service period. The Company uses the Black-Scholes option-pricing model to estimate the fair value of its stock-based awards. Stock-based compensation expense is recognized using the straight-line method. Stock-based compensation expense is based on the value of the portion of stock-based payment awards that is ultimately expected to vest. As such, the Company's stock-based compensation is reduced for the estimated forfeitures at the date of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company accounts for compensation expense related to stock options granted to non-employees based on the fair values estimated using the Black-Scholes model. Stock options granted to non-employees are remeasured at each reporting date until the award is vested. Foreign currency transactions The Company uses the U.S. dollar as its functional currency for its subsidiary in Chile. Foreign currency assets and liabilities are remeasured into U.S. dollars using the end of period exchange rates except for nonmonetary assets and liabilities, which are remeasured using historical exchange rates. Expenses are remeasured using an average exchange rate for the respective period. Gains or losses from foreign currency transactions are included in other income (expense), net, on the consolidated statements of operations. Foreign currency transaction gains and losses have not been significant to the consolidated financial statements for all periods presented. Comprehensive loss Comprehensive loss is composed 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(deficit), but are excluded from net loss. The Company's other comprehensive loss consists of unrealized gains and losses on investments in available-for-sale securities. Net loss per share attributable to common stockholders Basic net loss per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common share equivalents outstanding for the period determined using the treasury stock method. Potentially dilutive securities consisting of convertible preferred stock, options to purchase common stock and restricted stock units are considered to be common stock equivalents and were excluded from the calculation of diluted net loss per share attributable to common stockholders because their effect would be antidilutive for all periods presented. Common shares subject to repurchase are excluded from weighted-average shares. For the years ended December 31, 2015, 2014 and 2013; 4,659, 23,903 and 54,407 shares subject to repurchase, respectively, are excluded from the basic loss per share calculation. Recent accounting pronouncements In February 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-02, Leases (Topic 842). Under the new guidance, lessees will be required to recognize a lease liability and a right-of-use asset for all leases (with the exception of short-term leases) at the commencement date. Lessor accounting under ASU 2016-02 is largely unchanged. ASU 2016-02 is effective for annual and interim periods beginning on or after December 15, 2018 and early adoption is permitted. Under ASU 2016-02, lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. Lessees and lessors may not apply a full retrospective transition approach. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected an implementation date nor has it determined the effect of the standard on its ongoing financial reporting. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes to simplify the presentation of deferred income taxes. The amendments in this update require that deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. The Company has elected to early adopt ASU 2015-17 as of December 31, 2015. Because the net deferred tax assets have been offset by a valuation allowance and the deferred tax liabilities were not material no deferred tax assets or liabilities were disclosed in prior years in the classified balance sheet and therefore this early adoption has no impact on the Company's consolidated financial statements for the periods presented. In April, 2015, the FASB issued ASU 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. ASU 2015-03 simplifies the presentation of debt issuance costs and requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the debt liability instead of as an asset. ASU 2015-03 is effective for annual and interim periods beginning on or after December 15, 2015 and early adoption is permitted. The Company early adopted ASU 2015-03 in the second quarter of 2015 and the adoption of this standard did not have an impact on the Company's consolidated financial statements. In May, 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers ("ASU 2014-09"), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. In August, 2015, the FASB issued ASU 2015-14, Revenue from Contracts with Customers (Topic 606). ASU 2015-14 defers the effective date of ASU 2014-09 for public business entities by one year to annual reporting periods beginning after December 15, 2017. Therefore, the new standard will become effective for the Company on January 1, 2018 and early application is permitted for periods beginning on or after January 1, 2017. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected an implementation date or a transition method nor has it determined the effect of the standard on its ongoing financial reporting. In August 2014, the FASB issued ASU No. 2014-15 (Subtopic 205- 40), Presentation of Financial Statements—Going Concern: Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern ("ASU 2014-15"), which provides guidance about management's responsibility to evaluate whether there is substantial doubt about the Company's ability to continue as a going concern and to provide related footnote disclosure. ASU 2014-15 will be effective in the fourth quarter of 2016. Early application is permitted. The adoption of this standard is not expected to have an effect on the Company's consolidated financial statements.

Balance sheet components

Balance sheet components	12 Months Ended
	Dec. 31, 2015
Balance sheet components
Balance sheet components	3. Balance sheet components Cash equivalents and marketable securities The following is a summary of cash equivalents and marketable securities (in thousands). December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds $ $ — $ — $ U.S. treasury notes — — U.S. government agency securities ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Reported as: Cash equivalents $ Restricted cash Marketable securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total cash equivalents, restricted cash and marketable securities $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Reported as: Cash equivalents $ Restricted cash ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total cash equivalents, and restricted cash $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes the available-for-sale securities that were in an unrealized loss position as of December 31, 2015, having been in such a position for less than 12 months, and none having been deemed to be other-than-temporarily impaired (in thousands): Gross Unrealized Losses Estimated Fair Value U.S. government agency securities $ $ None of the available-for-sale securities held as of December 31, 2015 has been in a continuous unrealized loss position for more than one year. As of December 31, 2015, unrealized losses on available-for-sale investments are not attributed to credit risk and are considered to be temporary. The Company believes that it is more-likely-than-not that investments in an unrealized loss position will be held until maturity or the recovery of the cost basis of the investment. To date, the Company has not recorded any impairment charges on marketable securities related to other-than-temporary declines in market value. At December 31, 2015, the remaining contractual maturities of available-for-sale securities were less than one year. For the year ended December 31, 2015, realized gains or losses on available-for-sale securities were de minimis. There were no available-for-sale marketable securities held by the Company at December 31, 2014. Property and equipment, net Property and equipment consisted of the following (in thousands): December 31, 2015 2014 Leasehold improvements $ $ Laboratory equipment Equipment under capital lease Computer equipment Software Furniture and fixtures Automobiles — Construction-in-progress ​ ​ ​ ​ ​ ​ ​ ​ Total property and equipment, gross Accumulated depreciation and amortization ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total property and equipment, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Included in the construction-in-progress balance as of December 31, 2014 was $2.9 million of capital lease equipment that had not been placed in service. Depreciation and amortization expense was $5.3 million, $2.3 million and $0.9 million for the years ended December 31, 2015, 2014 and 2013, respectively. Accrued liabilities Accrued liabilities consisted of the following (in thousands): Year ended December 31, 2015 2014 Accrued compensation and related expenses $ $ Accrued laboratory materials purchases — Accrued professional services Accrued costs for construction-in-progress — Other ​ ​ ​ ​ ​ ​ ​ ​ Total accrued liabilities $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Fair value measurements

Fair value measurements	12 Months Ended
	Dec. 31, 2015
Fair value measurements
Fair value measurements	4. Fair value measurements Financial assets and liabilities are recorded at fair value. The carrying amounts of certain of the Company's financial instruments, including cash equivalents, and accounts payable, are valued at cost, which approximates fair value due to their short maturities. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The authoritative guidance establishes a three-level valuation hierarchy that prioritizes the inputs to valuation techniques used to measure fair value based upon whether such inputs are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect market assumptions made by the reporting entity. The three-level hierarchy for the inputs to valuation techniques is briefly summarized as follows: Level 1—Observable inputs such as quoted prices (unadjusted) for identical instruments in active markets. Level 2—Observable inputs such as quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-derived valuations whose significant inputs are observable. Level 3—Unobservable inputs that reflect the reporting entity's own assumptions. The following tables set forth the fair value of the Company's consolidated financial instruments that were measured at fair value on a recurring basis as of December 31, 2015 and 2014 (in thousands): December 31, 2015 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ $ — $ — $ U.S. treasury notes — — U.S. government agency securities — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total financial assets $ $ $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2014 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total financial assets $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The Company's debt securities of U.S. government agency entities are classified as Level 2 as they are valued based upon quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. Where applicable these models project future cash flows and discount the future amounts to a present value using market-based observable inputs obtained from various third party data providers, including but not limited to, benchmark yields, interest rate curves, reported trades, broker/dealer quotes and reference data. There were no transfers between Level 1 and Level 2 during the periods presented. The fair value of the Company's outstanding debt is estimated using the net present value of the payments, discounted at an interest rate that is consistent with market interest rates, which is a Level 2 input. The carrying amount and the estimated fair value of the Company's outstanding debt at December 31, 2015, and 2014, are as follows (in thousands): December 31, 2015 December 31, 2014 Carrying Amount Fair Value Carrying Amount Fair Value Debt $ $ $ — $ —

Commitments and contingencies

Commitments and contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and contingencies.
Commitments and contingencies	5. Commitments and contingencies Operating Leases Through December 31, 2014,the Company had entered into various non-cancelable operating lease agreements for office and laboratory facilities located in California with lease periods expiring between 2016 and 2020 and for laboratory space in Santiago, Chile with a lease term expiring in 2017. In March 2015, the Company leased additional space in San Francisco and Oakland, California. The leases expire in April and June 2017, respectively. In April 2015 the Company leased additional space in Cambridge, Massachusetts; this lease expires in January 2018. Some of the lease agreements include scheduled rent increases over the terms of the leases. Rent increases, including the impact of rent holidays and leasehold improvement allowances from landlords, are recognized as deferred rent and are amortized on a straight-line basis over the term of the original lease. In September 2015, the Company entered into a lease agreement for a laboratory and headquarters in San Francisco, California. This lease expires in July 2026 and the Company may renew the lease for an additional ten years. The Company has determined the lease term to be a ten-year period expiring in 2026. The lease term commenced when the Company took occupancy of the facility in the first quarter of 2016. In connection with the execution of the lease, the Company provided a security deposit of approximately $4.6 million which is included in restricted cash in the Company's consolidated balance sheets. Minimum annual rent under the lease is subject to increases based on stated rental adjustment terms. In addition, per the terms of the lease, the Company will receive a $5.2 million lease incentive in the form of reimbursement from the landlord for a portion of the costs of leasehold improvements the Company makes to the facility. The assets purchased with the lease incentive will be included in property and equipment, net in the Company's consolidated balance sheets and the lease incentive will be recognized as a reduction of rental expense on a straight-line basis over the term of the lease. At December 31, 2015, none of the incentive had been utilized by the Company. At December 31, 2015, aggregate future minimum lease payments for the new facility are approximately $72.0 million. In addition to the security deposit of approximately $4.6 million for the new laboratory and headquarters facility, the Company has provided security deposits of $1.5 million and $1.4 million as of December 31, 2015 and 2014, respectively, as collateral for other leases, which are included in other assets in the Company's balance sheets. Future minimum payments under non-cancelable operating leases as of December 31, 2015 are as follows (in thousands): Year ending December 31, Amounts 2016 $ 2017 2018 2019 2020 Thereafter ​ ​ ​ ​ ​ Total minimum lease payments $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Rent expense was $3.7 million, $1.4 million and $0.8 million for the years ended December 31, 2015, 2014 and 2013, respectively. Equipment Financing In July 2015, the Company entered into a Loan and Security Agreement (the "Loan Agreement") with a bank under which term loans for purchases of equipment up to an aggregate of $15.0 million are available in tranches not to exceed $2.0 million, other than the initial $2.5 million tranche on the date of the Loan Agreement. The Company may request additional tranches to finance the purchase of equipment through December 31, 2016, subject to certain restrictions. The term loans under the Loan Agreement bear interest at a floating rate equal to 0.25% below the prime rate as published in the Wall Street Journal effective on the date the change in the prime rate becomes effective. The Company is required to repay the outstanding principal and accrued but unpaid interest on each tranche in equal monthly installments beginning one month after each advance and ending on July 17, 2020 (the "Term Date"). Any then-unpaid principal and interest on advances under the Loan Agreement are payable on the Term Date. The Company may, at its option, prepay the borrowings by paying the lender a prepayment premium. The Company's obligations under the Loan Agreement are subject to covenants, including covenants to maintain a minimum liquidity level with the bank, and additional covenants limiting the Company's ability to dispose of assets, undergo a change in control, merge with or acquire other entities, incur debt, incur liens, pay dividends or other distributions to holders of its capital stock, repurchase stock and make investments, in each case subject to certain exceptions. As of December 31, 2015, the Company was in compliance with all covenants under the Loan Agreement. The Company's obligations under the Loan Agreement are secured by a security interest on substantially all of its assets, excluding its intellectual property and certain other assets. At December 31, 2015, obligations under the Loan Agreement were $7.0 million. Debt issuance costs related to the Loan Agreement of $47,000 were recorded as a direct deduction from the debt liability and are amortized to interest expense over the term of the Loan Agreement in accordance with ASU 2015-03. Future payments under the Loan Agreement as of December 31, 2015 are as follows (in thousands): Year ending December 31, Amounts 2016 $ 2017 2018 2019 2020 Thereafter — ​ ​ ​ ​ ​ Total remaining debt payments Less: amount representing debt discount ) Less: amount representing interest ) ​ ​ ​ ​ ​ Present value of remaining debt payments Less: current portion ) ​ ​ ​ ​ ​ Total noncurrent debt obligation $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital leases The Company has entered into various capital lease agreements to obtain lab equipment. The terms of the capital leases is typically three years with interest rates ranging from 3.8% to 4.3%. The leases are secured by the underlying equipment. The portion of the future payments designated as principal repayment was classified as a capital lease obligation on the consolidated balance sheets. Future payments under the capital lease as of December 31, 2015 are as follows (in thousands): Year ending December 31, Amounts 2016 $ 2017 2018 ​ ​ ​ ​ ​ Total capital lease obligations Less: amount representing interest ) ​ ​ ​ ​ ​ Present value of net minimum capital lease payments Less: current portion ) ​ ​ ​ ​ ​ Total noncurrent capital lease obligations $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest expense related to capital leases was $141,000, $61,000 and $59,000 for the years ended December 31, 2015, 2014 and 2013, respectively. Property and equipment under capital leases was $8.2 million and $6.6 million as of December 31, 2015 and 2014, respectively, including $2.9 million of capital lease equipment that had not been placed in service as of December 31, 2014. Accumulated depreciation and amortization, collectively, on these assets was $2.8 million and $1.4 million as of December 31, 2015 and 2014, respectively. Guarantees and indemnifications As permitted under Delaware law and in accordance with the Company's bylaws, the Company indemnifies its officers and directors for certain events or occurrences while the officer or director is or was serving in such capacity. The maximum amount of potential future indemnification is unlimited; however, the Company currently holds director and officer liability insurance. This insurance allows the transfer of the risk associated with the Company's exposure and may enable it to recover a portion of any future amounts paid. The Company believes the fair value of these indemnification agreements is minimal. Accordingly, the Company has not recorded any liabilities associated with these indemnification agreements as of December 31, 2015 or 2014. Contingencies On September 16, 2015, GeneDx, Inc. and Bio-Reference Laboratories, Inc. filed an action against the Company in the U.S. District Court for the District of New Jersey. The Complaint alleges that the Company wrongfully solicited and hired employees away from the plaintiffs in order to acquire access to trade secrets and other confidential business information belonging to the plaintiffs. The Complaint alleges claims for relief based on legal theories of unfair competition, tortious interference with prospective economic advantage, tortious interference with contract, and trade secret misappropriation, and seeks injunctive relief; damages, including punitive damages; and attorneys' fees and costs. On October 22, 2015, the Company filed a motion to dismiss the action for lack of personal jurisdiction and, in the alternative, to transfer the action to the U.S. District Court for the Northern District of California. On November 13, 2015, the plaintiffs filed their First Amended Complaint. On December 14, 2015, the Company responded by again filing a motion to dismiss the action for lack of personal jurisdiction and, in the alternative, to transfer the action to the U.S. District Court for the Northern District of California. The parties are negotiating the exchange of information regarding the issue of personal jurisdiction, and have extended the plaintiffs' deadline to respond to the motion pending the outcome of that negotiation. The current due date for the plaintiffs' response is March 21, 2016. The Company believes the action is without merit and intends to defend itself vigorously. The Company was not a party to any other material legal proceedings at December 31, 2015, or at the date of this report. The Company may from time to time become involved in various legal proceedings arising in the ordinary course of business, and the resolution of any such claims could be material.

Convertible preferred stock

Convertible preferred stock	12 Months Ended
	Dec. 31, 2015
Convertible preferred stock
Convertible preferred stock	6. Convertible preferred stock Convertible preferred stock as of December 31, 2014 consisted of the following (in thousands, except share and per share data): Shares authorized Original issue price Shares issued and outstanding Aggregate liquidation amount Proceeds, net of issuance costs Series A $ $ $ Series B Series C Series D Series E Series F ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at December 31, 2014 $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Upon the closing of the IPO in February 2015, the 141,131,524 shares of convertible preferred stock then outstanding converted into 23,521,889 shares of common stock.

Stockholders' equity (deficit)

Stockholders' equity (deficit)	12 Months Ended
	Dec. 31, 2015
Stockholders' deficit
Stockholders' deficit	7. Stockholders' equity (deficit) Common stock The holders of each share of common stock have one vote for each share of stock. The common stockholders are also entitled to receive dividends whenever funds and assets are legally available and when declared by the Board of Directors, subject to the prior rights of holders of all series of convertible preferred stock outstanding. As of December 31, 2015 and 2014, the Company had reserved shares of common stock, on an as-if converted basis, for issuance as follows: As of December 31, 2015 2014 Conversion of convertible preferred stock — Options issued and outstanding Options available for grant under stock option plan Shares reserved for issuance under the 2015 Employee Stock Purchase Plan — ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Stock plans

Stock plans	12 Months Ended
	Dec. 31, 2015
Stock incentive plan
Stock incentive plan	8. Stock plans Stock incentive plans In 2010, the Company adopted the 2010 Incentive Plan (the "2010 Plan"). The 2010 Plan provides for the granting of stock-based awards to employees, directors, and consultants under terms and provisions established by the Board of Directors. Under the terms of the 2010 Plan, options may be granted at an exercise price not less than fair market value. For employees holding more than 10% of the voting rights of all classes of stock, the exercise prices for incentive and nonstatutory stock options must be at least 110% of fair market of the common stock on the grant date, as determined by the Board of Directors. The terms of options granted under the 2010 Plan may not exceed ten years. In January 2015, the Company adopted the 2015 Stock Incentive Plan, (the "2015 Plan"), which became effective upon the closing of the IPO. The 2015 Plan had 4,370,452 shares of common stock reserved for future issuance at the time of its effectiveness, which included 120,452 shares under the 2010 Plan which were transferred to the 2015 Plan upon effectiveness of the 2015 Plan. The 2015 Plan provides for automatic annual increases in shares available for grant, beginning on January 1, 2016 through January 1, 2025. In addition, shares subject to awards under the 2010 Plan that are forfeited or terminated will be added to the 2015 Plan. The 2015 Plan provides for the grant of incentive stock options, nonstatutory stock options, restricted stock awards, stock units, stock appreciation rights and other forms of equity compensation, all of which may be granted to employees, including officers, non-employee directors and consultants. Additionally, the 2015 Plan provides for the grant of cash-based awards. Options granted generally vest over a period of four years. Typically, the vesting schedule for options granted to newly hired employees provides that 1 / 4 of the grant vests upon the first anniversary of the employee's date of hire, with the remainder of the shares vesting monthly thereafter at a rate of 1 / 48 of the total shares subject to the option. All other options typically vest in equal monthly installments over the four-year vesting schedule. Restricted stock units generally vest over a period of three years. Typically, the vesting schedule for restricted stock units provides that one third of the grant vests upon each anniversary of the grant date. 2015 employee stock purchase plan In January 2015, the Company adopted the 2015 Employee Stock Purchase Plan (the "ESPP"), which became effective upon the closing of the IPO. A total of 325,000 shares of common stock are reserved for issuance under the ESPP. Eligible employees may purchase common stock at 85% of the lesser of the fair market value of common stock on the purchase date or last trading day preceding the offering date. The ESPP provides for automatic annual increases in shares available for grant, beginning on January 1, 2016 through January 1, 2025. The initial ESPP purchase period commenced in the fourth quarter of 2015. Activity under the 2010 Plan and the 2015 Plan is set forth below (in thousands, except share and per share amounts and years): Shares available for grant Stock options outstanding Weighted- average exercise price Weighted- average remaining contractual life (years) Aggregate intrinsic value Balances at December 31, 2013 $ $ Additional shares reserved — — Repurchase of unvested early exercise shares — — Options granted ) Options cancelled ) Options exercised — ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at December 31, 2014 $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additional shares reserved — Options granted ) Options cancelled ) Options exercised — ) Restricted stock units granted ) — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at December 31, 2015 $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options exercisable at December 31, 2015 $ $ Options vested and expected to vest at December 31, 2015 $ $ The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying stock options and the fair value of the Company's common stock for stock options that were in-the-money. The weighted-average fair value of options to purchase common stock granted was $6.26, $4.68 and $1.83 per share in the years ended December 31, 2015, 2014 and 2013, respectively. The weighted-average fair value of restricted stock units granted was $10.72 , $0.00, and $0.00 in the years ended December 31, 2015, 2014 and 2013, respectively. The fair value of options to purchase common stock vested was $2,128,000, $494,000 and $204,000 in the years ended December 31, 2015, 2014 and 2013, respectively. The intrinsic value of options to purchase common stock exercised was $1,285,000, $644,000 and $60,000 in the years ended December 31, 2015, 2014 and 2013, respectively. The following table summarizes RSU activity for the year ended December 31, 2015: Number of Shares Weighted- Average Grant Date Fair Value Balance at December 31, 2014 — $ — RSUs granted RSUs vested — — RSUs cancelled ) ​ ​ ​ ​ ​ ​ ​ ​ Balance at December 31, 2015 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock-based compensation The Company uses the grant date fair value of its common stock to value both employee and non-employee options when granted. The Company revalues non-employee options each reporting period using the fair market value of the Company's common stock as of the last day of each reporting period. In determining the fair value of the stock-based awards, the Company uses the Black-Scholes option-pricing model and assumptions discussed below. Each of these inputs is subjective and its determination generally requires significant judgment. Expected term —The expected term represents the period that the Company's stock-based awards are expected to be outstanding and is determined using the simplified method (based on the midpoint between the vesting date and the end of the contractual term). Expected volatility —Because the Company was privately held and did not have any trading history for its common stock, the expected volatility was estimated based on the average volatility for comparable publicly traded biopharmaceutical companies over a period equal to the expected term of the stock option grants. When selecting comparable publicly traded companies in a similar industry on which it has based its expected stock price volatility, the Company selected companies with comparable characteristics to it, including enterprise value, risk profiles, position within the industry, and with historical share price information sufficient to meet the expected life of the stock-based awards. The historical volatility data was computed using the daily closing prices for the selected companies' common stock during the equivalent period of the calculated expected term of the stock-based awards. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available. Risk-free interest rate —The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of the option. Dividend yield —The Company has never paid dividends on its common stock and has no plans to pay dividends on its common stock. Therefore, the Company used an expected dividend yield of zero. The fair value of share-based payments for option granted to employees and directors was estimated on the date of grant using the Black-Scholes option- pricing valuation model based on the following assumptions: Year ended December 31, 2015 2014 2013 Expected term (in years) 6.03 6.03 6.03 Expected volatility 68.2 - 79.7% 83.8 - 86.6% 88.5 - 94.5% Risk-free interest rate 1.28 - 1.86% 1.53 - 1.91% 0.99 - 1.97% Dividend yield — — — The fair value of the ESPP is estimated using the Black-Scholes option pricing model. For the year ended December 31, 2015, the weighted average grant date fair value per share for the ESPP was $2.17. Stock-based compensation expense for the ESPP was $102,000 for the year ended December 31, 2015. For the year ended December 31, 2015, the fair value of ESPP was estimated using the following assumptions: Year ended December 31, 2015 Expected term (in years) Expected volatility % Risk-free interest rate % Dividend yield — The ESPP commenced in November 2015. No shares of common stock were purchased pursuant to the ESPP in 2015. Cash received from payroll deductions pursuant to the ESPP in 2015 was $259,000. Stock-based compensation related to stock options granted to non-employees is recognized as the stock options are earned. The fair value of the stock options granted is calculated at each reporting date using the Black-Scholes option pricing model based on the following assumptions: Year ended December 31, 2015 2014 2013 Expected term (in years) 7.25 - 9.82 9.37 - 9.40 9.25 - 9.60 Expected volatility 69.9 - 78.7% 83.8% 88.5% Risk-free interest rate 1.86 - 2.25% 1.99 - 2.41% 2.85 - 2.94% Dividend yield — — — The following table summarizes stock-based compensation expense for the years ended December 31, 2015, 2014 and 2013 included in the statements of operations and comprehensive loss as follows (in thousands): Year ended December 31, 2015 2014 2013 Cost of revenue $ $ $ Research and development Selling and marketing General and administrative ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total stock-based compensation expense $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2015, unrecognized compensation expense related to unvested options, net of estimated forfeitures, was $14.6 million, which the Company expects to recognize on a straight-line basis over a weighted- average period of 3.3 years. Unrecognized compensation expense related to restricted stock units at December 31, 2015 was $4.6 million which the Company expects to recognize on a straight-line basis over a weighted- average period of 2.7 years. There was no capitalized stock-based employee compensation as of December 31, 2015.

Income taxes

Income taxes	12 Months Ended
	Dec. 31, 2015
Income taxes
Income taxes	9. Income taxes The Company did not record a provision or benefit for income taxes during the years ended December 31, 2015, 2014 and 2013. The components of loss before income taxes by U.S. and foreign jurisdictions are as follows (in thousands): Year ended December 31, 2015 2014 2013 United States $ $ $ Foreign ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table presents a reconciliation of the tax expense computed at the statutory federal rate and the Company's tax expense for the periods presented: Year ended December 31, 2015 2014 2013 U.S. federal taxes at statutory rate % % % State taxes (net of federal benefit) Non-deductible expenses ) ) ) Foreign tax differential ) ) ) Change in valuation allowance ) ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total % % % The tax effects of temporary differences and carryforwards that give rise to significant portions of the deferred tax assets are as follows (in thousands): As of December 31, 2015 2014 Deferred tax assets: Net operating loss carryforwards $ $ Tax credits Accruals and other ​ ​ ​ ​ ​ ​ ​ ​ Gross deferred tax assets Valuation allowance ) ) ​ ​ ​ ​ ​ ​ ​ ​ Net deferred tax assets Deferred tax liabilities: Property and equipment $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ Total deferred tax liabilities ) ) ​ ​ ​ ​ ​ ​ ​ ​ Net deferred tax assets $ — $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The Company has established a full valuation allowance against its deferred tax assets due to the uncertainty surrounding realization of such assets. The valuation allowance increased by $30.8 million and $16.1 million during the years ended December 31, 2015 and 2014, respectively. As of December 31, 2015, the Company had net operating loss carryforwards of approximately $147.0 million and $96.0 million available to reduce future taxable income, if any, for Federal and California state income tax purposes, respectively. The Company tracks a portion of its deferred tax assets attributable to stock option benefits in a separate memo account. Therefore these amounts are not included in the Company's gross or net deferred tax assets. The benefit of these stock options will not be recorded in equity unless it reduces taxes payable. As of December 31, 2015, the portion of the Federal and state net operating loss related to stock option benefits is approximately $500,000. The U.S. Federal and California state net operating loss carryforwards will begin to expire in 2030. As of December 31, 2015, the Company had net operating loss carryforwards for foreign income tax purposes of $4.0 million which have no expiration date. As of December 31, 2015, the Company had research and development credit carryforwards of approximately $3.7 million and $3.3 million available to reduce its future tax liability, if any, for Federal and California state income tax purposes, respectively. The Federal credit carryforwards begin to expire in 2030. California credit carryforwards have no expiration date. As of December 31, 2015, the Company has other tax credits of $18,000 that have no expiration period for the majority of the credits. Utilization of the net operating loss carryforwards and credits may be subject to an annual limitation due to the ownership change limitations provided by the Internal Revenue Code of 1986 and similar state provisions. The annual limitation may result in the expiration of net operating losses and credits before utilization. No Section 382 study has been completed as of December 31, 2015. As of December 31, 2015, the Company had unrecognized tax benefits of $11.4 million, none of which would currently affect the Company's effective tax rate if recognized due to the Company's deferred tax assets being fully offset by a valuation allowance. The Company has not accrued interest and penalties related to the unrecognized tax benefits reflected in the financial statements for the years ended December 31, 2015, 2014 and 2013. Unrecognized tax benefits are not expected to change in the next 12 months. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Year ended December 31, 2015 2014 2013 Unrecognized tax benefits, beginning of period $ $ $ Gross increases—current period tax positions Gross increases—prior period tax positions — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unrecognized tax benefits, end of period $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The Company's policy is to include penalties and interest expense related to income taxes as a component of tax expense. There was no interest expense or penalties related to unrecognized tax benefits recorded through December 31, 2015. The Company's major tax jurisdictions are the United States and California. All of the Company's tax years will remain open for examination by the Federal and state tax authorities for three and four years, respectively, from the date of utilization of the net operating loss or research and development credit. The Company does not have any tax audits pending.

Net loss per share attributable

Net loss per share attributable to common stockholders	12 Months Ended
	Dec. 31, 2015
Net loss per share attributable to common stockholders
Net loss per share attributable to common stockholders	10. Net loss per share attributable to common stockholders The following table presents the calculation of basic and diluted net loss per share attributable to common stockholders for the years ended December 31, 2015, 2014 and 2013 (in thousands, except share and per share amounts): Year ended December 31, 2015 2014 2013 Net loss $ ) $ ) $ ) Less: dividends on convertible preferred stock — — ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to common stockholders $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shares used in computing net loss per share attributable to common stockholders, basic and diluted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss per share attributable to common stockholders, basic and diluted $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following outstanding shares of common stock equivalents have been excluded from diluted net loss per share attributable to common stockholders for the years ended December 31, 2015, 2014 and 2013 because their inclusion would be anti-dilutive: Year ended December 31, 2015 2014 2013 Shares of common stock subject to outstanding options Shares of common stock subject to outstanding restricted stock unit awards — — Shares of common stock pursuant to employee stock purchase plan — — Shares of common stock subject to conversion of preferred stock — Shares of common stock subject to unvested early exercise of outstanding options subject to repurchase ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total shares of common stock equivalents ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Geographic information

Geographic information	12 Months Ended
	Dec. 31, 2015
Geographic information
Geographic information	11. Geographic information Revenue by country is determined based on the billing address of the customer. The following presents revenue by country for December 31, 2015, 2014 and 2013 (in thousands): December 31, 2015 2014 2013 United States $ $ $ Israel Canada Rest of world ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-lived assets (net) by location are summarized as follows (in thousands): December 31, 2015 2014 United States $ $ Chile ​ ​ ​ ​ ​ ​ ​ ​ Total long-lived assets, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Selected Quarterly Data (Unaudi

Selected Quarterly Data (Unaudited)	12 Months Ended
	Dec. 31, 2015
Selected Quarterly Data (Unaudited)
Selected Quarterly Data (Unaudited)	12. Selected Quarterly Data (Unaudited) The following table contains quarterly financial information for 2015 and 2014. The Company believes that the following information reflects all normal recurring adjustments necessary for a fair statement of the information for the periods presented. The operating results for any quarter are not necessarily indicative of results for any future period. Three months ended (In thousands, except per share amounts) Dec 31, 2015 Sept 30, 2015 June 30, 2015 Mar 31, 2015 Dec 31, 2014 Sept 30, 2014 June 30, 2014 Mar 31, 2014 Revenue $ $ $ $ $ $ $ $ Loss from operations $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ ) Net loss $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ ) Net loss attributable to common stockholders $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ ) Net loss per share attributable to common stockholders, basic and diluted $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ )

Summary of significant accoun22

Summary of significant accounting policies (Policies)	12 Months Ended
	Dec. 31, 2015
Summary of significant accounting policies
Principles of consolidation	Principles of consolidation The Company's consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America ("U.S. GAAP"). The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Use of estimates	Use of estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. The Company believes judgment is involved in determining revenue recognition; the recoverability of long-lived assets; the fair value of the Company's common stock prior to the IPO; stock-based compensation expense; and income tax uncertainties. The Company bases these estimates on historical and anticipated results, trends, and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. Actual results could differ materially from those estimates and assumptions.
Concentrations of credit risk and other risks and uncertainties	Concentrations of credit risk and other risks and uncertainties Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents. The Company's cash and cash equivalents are held by financial institutions in the United States and Chile. Such deposits may exceed federally insured limits. As of December 31, 2015, substantially all of the Company's revenue has been derived from sales of its assays. Significant customers are those which represent 10% or more of the Company's total revenue for each year presented on the statements of operations and comprehensive loss. For each significant customer, revenue as a percentage of total revenue are as follows: December 31, Customers 2015 2014 2013 Customer A * * % Customer B * % — Customer C % * * * Less than 10% of total revenue
Cash equivalents	Cash equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. Cash equivalents consist primarily of amounts invested in money market funds and U.S government agency securities.
Marketable securities	Marketable securities All marketable securities have been classified as "available-for-sale" and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. Management determines the appropriate classification of its marketable securities in debt securities at the time of purchase and reevaluates such designation as of each balance sheet date. Short-term marketable securities have maturities less than 365 days as of the balance sheet date. Unrealized gains and losses are excluded from earnings and are reported as a component of other comprehensive income (loss). Realized gains and losses and declines in fair value judged to be other than temporary, if any, on available-for-sale securities are included in interest and other income (expense), net. The cost of securities sold is based on the specific-identification method. Interest on marketable securities is included in interest and other income (expense), net.
Restricted cash	Restricted cash Restricted cash consists of money market funds that serve as: collateral for a security deposit for the Company's lease agreement for a laboratory and headquarters entered into in September 2015; collateral for a credit card agreement at one of the Company's financial institutions; and for securing a letter of credit as collateral for the Company's Cambridge Massachusetts facility sublease agreement.
Internal-use software	Internal-use software The Company capitalizes third-party costs incurred in the application development stage to design and implement internal-use software. Maintenance and training costs relating to internal-use software are expensed as incurred. Capitalized internal-use software costs are recorded as property and equipment and are amortized over estimated useful lives of up to three years on a straight line basis. Amortization of capitalized internal-use software costs is recorded as sales and marketing expense. During the years ended December 31, 2015, 2014 and 2013, the Company capitalized $1.5 million, $550,000 and $250,000, respectively, of internal-use software development costs. Internal-use software amortization was $718,000, $152,000, and zero, in 2015, 2014 and 2013, respectively. The carrying value of capitalized internal-use software at December 31, 2015 and 2014 was $1.4 million and $648,000, respectively. The weighted average useful life of capitalized internal-use software at December 31, 2015 was 13 months.
Deferred offering costs	Deferred offering costs Deferred offering costs, which primarily consist of direct incremental legal, accounting and other fees relating to the IPO, were initially capitalized. As of December 31, 2014, the Company capitalized $1.9 million of deferred offering costs in other assets on the consolidated balance sheets. The deferred offering costs were subsequently offset against IPO proceeds upon the closing of the IPO in February 2015.
Leases	Leases The Company rents its facilities under operating lease agreements and recognizes related rent expense on a straight-line basis over the term of the lease. Some of the lease agreements contain rent holidays, scheduled rent increases, lease incentives, and renewal options. Rent holidays and scheduled rent increases are included in the determination of rent expense to be recorded over the lease term. Lease incentives are recognized as a reduction of rent expense on a straight-line basis over the term of the lease. Renewals are not assumed in the determination of the lease term unless they are deemed to be reasonably assured at the inception of the lease. The Company recognizes rent expense beginning on the date it obtains the legal right to use and control the leased space.
Property and equipment	Property and equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, generally between three and seven years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life of the asset or the term of the lease. Amortization expense of assets acquired through capital leases is included in depreciation and amortization expense in the consolidated statements of operations and comprehensive loss. Maintenance and repairs are charged to expense as incurred, and improvements and betterments are capitalized. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet and any resulting gain or loss is reflected in the statements of operations and comprehensive loss in the period realized. The useful lives of the property and equipment are as follows: Furniture and fixtures 7 years Automobiles 7 years Laboratory equipment 5 years Computer equipment 3 years Software 3 years Leasehold improvements Shorter of lease term or estimated useful life
Long-lived assets	Long-lived assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An impairment loss is recognized when the total estimated future undiscounted cash flows expected to result from the use of the asset and its eventual disposition are less than its carrying amount. Impairment, if any, would be assessed using discounted cash flows or other appropriate measures of fair value. The Company has not recorded an impairment of any long-lived assets during any of the periods presented.
Fair value of financial instruments	Fair value of financial instruments The Company's financial instruments consist principally of cash and cash equivalents, marketable securities, accounts payable, capital leases and debt relating to equipment financing. The carrying amounts of certain of these financial instruments, including cash and cash equivalents, and accounts payable, approximate fair value due to their short maturities. Based on borrowing rates available to us, the carrying value of capital leases approximates fair value. See Note 4, "Fair value measurements" for further information on the fair value of the Company's financial instruments.
Revenue recognition	Revenue recognition Revenue is generated from the sale of tests that provide analysis and associated interpretation of the sequencing of parts of the genome. Revenue associated with subsequent re-requisition services was de minimis for all periods presented. Revenue is recognized when persuasive evidence of an arrangement exists; delivery has occurred or services have been rendered; the fee is fixed or determinable; and collectability is reasonably assured. The criterion for whether the fee is fixed or determinable and whether collectability is reasonably assured are based on management's judgments. When evaluating collectability, in situations where contracted reimbursement coverage does not exist, the Company considers whether the Company has sufficient history to reliably estimate a payer's individual payment patterns. The Company reviews the number of tests paid against the number of tests billed over at least several months of payment history and the payer's outstanding balance for unpaid tests to determine whether payments are being made at a consistently high percentage of tests billed and at appropriate amounts given the amount billed. For most payers, the Company has not been able to demonstrate a predictable pattern of collectability, and therefore recognizes revenue when payment is received. For payers who have demonstrated a consistent pattern of payment of tests billed at appropriate amounts, the Company recognizes revenue, at estimated realizable amounts, upon delivery of test results.
Cost of revenue	Cost of revenue Cost of revenue reflects the aggregate costs incurred in delivering the genetic testing results to clinicians and includes expenses for personnel costs including stock-based compensation, materials and supplies, equipment and infrastructure expenses associated with testing and allocated overhead including rent, equipment depreciation and utilities. Costs associated with performing the Company's test are recorded as the test is processed regardless of whether and when revenue is recognized with respect to that test.
Research and development	Research and development Research and development costs are charged to operations as incurred. Research and development costs include, but are not limited to, payroll and personnel- related expenses, stock-based compensation expense, reagents and laboratory supplies, consulting costs, and allocated overhead including rent, information technology, equipment depreciation and utilities.
Income taxes	Income taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the 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. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized.
Stock-based compensation	Stock-based compensation The Company measures its stock-based payment awards made to employees and directors based on the estimated fair values of the awards and recognizes the compensation expense over the requisite service period. The Company uses the Black-Scholes option-pricing model to estimate the fair value of its stock-based awards. Stock-based compensation expense is recognized using the straight-line method. Stock-based compensation expense is based on the value of the portion of stock-based payment awards that is ultimately expected to vest. As such, the Company's stock-based compensation is reduced for the estimated forfeitures at the date of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company accounts for compensation expense related to stock options granted to non-employees based on the fair values estimated using the Black-Scholes model. Stock options granted to non-employees are remeasured at each reporting date until the award is vested.
Foreign currency transactions	Foreign currency transactions The Company uses the U.S. dollar as its functional currency for its subsidiary in Chile. Foreign currency assets and liabilities are remeasured into U.S. dollars using the end of period exchange rates except for nonmonetary assets and liabilities, which are remeasured using historical exchange rates. Expenses are remeasured using an average exchange rate for the respective period. Gains or losses from foreign currency transactions are included in other income (expense), net, on the consolidated statements of operations. Foreign currency transaction gains and losses have not been significant to the consolidated financial statements for all periods presented.
Comprehensive loss	Comprehensive loss Comprehensive loss is composed 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(deficit), but are excluded from net loss. The Company's other comprehensive loss consists of unrealized gains and losses on investments in available-for-sale securities.
Net loss per share attributable to common stockholders	Net loss per share attributable to common stockholders Basic net loss per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common share equivalents outstanding for the period determined using the treasury stock method. Potentially dilutive securities consisting of convertible preferred stock, options to purchase common stock and restricted stock units are considered to be common stock equivalents and were excluded from the calculation of diluted net loss per share attributable to common stockholders because their effect would be antidilutive for all periods presented. Common shares subject to repurchase are excluded from weighted-average shares. For the years ended December 31, 2015, 2014 and 2013; 4,659, 23,903 and 54,407 shares subject to repurchase, respectively, are excluded from the basic loss per share calculation.
Recent accounting pronouncements	Recent accounting pronouncements In February 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-02, Leases (Topic 842). Under the new guidance, lessees will be required to recognize a lease liability and a right-of-use asset for all leases (with the exception of short-term leases) at the commencement date. Lessor accounting under ASU 2016-02 is largely unchanged. ASU 2016-02 is effective for annual and interim periods beginning on or after December 15, 2018 and early adoption is permitted. Under ASU 2016-02, lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. Lessees and lessors may not apply a full retrospective transition approach. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected an implementation date nor has it determined the effect of the standard on its ongoing financial reporting. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes to simplify the presentation of deferred income taxes. The amendments in this update require that deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. The Company has elected to early adopt ASU 2015-17 as of December 31, 2015. Because the net deferred tax assets have been offset by a valuation allowance and the deferred tax liabilities were not material no deferred tax assets or liabilities were disclosed in prior years in the classified balance sheet and therefore this early adoption has no impact on the Company's consolidated financial statements for the periods presented. In April, 2015, the FASB issued ASU 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. ASU 2015-03 simplifies the presentation of debt issuance costs and requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the debt liability instead of as an asset. ASU 2015-03 is effective for annual and interim periods beginning on or after December 15, 2015 and early adoption is permitted. The Company early adopted ASU 2015-03 in the second quarter of 2015 and the adoption of this standard did not have an impact on the Company's consolidated financial statements. In May, 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers ("ASU 2014-09"), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. In August, 2015, the FASB issued ASU 2015-14, Revenue from Contracts with Customers (Topic 606). ASU 2015-14 defers the effective date of ASU 2014-09 for public business entities by one year to annual reporting periods beginning after December 15, 2017. Therefore, the new standard will become effective for the Company on January 1, 2018 and early application is permitted for periods beginning on or after January 1, 2017. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected an implementation date or a transition method nor has it determined the effect of the standard on its ongoing financial reporting. In August 2014, the FASB issued ASU No. 2014-15 (Subtopic 205- 40), Presentation of Financial Statements—Going Concern: Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern ("ASU 2014-15"), which provides guidance about management's responsibility to evaluate whether there is substantial doubt about the Company's ability to continue as a going concern and to provide related footnote disclosure. ASU 2014-15 will be effective in the fourth quarter of 2016. Early application is permitted. The adoption of this standard is not expected to have an effect on the Company's consolidated financial statements.

Summary of significant accoun23

Summary of significant accounting policies (Tables)	12 Months Ended
	Dec. 31, 2015
Summary of significant accounting policies
Schedule significant customer, revenue as a percentage	December 31, Customers 2015 2014 2013 Customer A * * % Customer B * % — Customer C % * * * Less than 10% of total revenue
Schedule of useful lives of property and equipment	Furniture and fixtures 7 years Automobiles 7 years Laboratory equipment 5 years Computer equipment 3 years Software 3 years Leasehold improvements Shorter of lease term or estimated useful life

Balance sheet components (Table

Balance sheet components (Tables)	12 Months Ended
	Dec. 31, 2015
Balance sheet components
Schedule cash, cash equivalents, short-term investments, and long-term investments	The following is a summary of cash equivalents and marketable securities (in thousands). December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds $ $ — $ — $ U.S. treasury notes — — U.S. government agency securities ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ $ $ ) $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Reported as: Cash equivalents $ Restricted cash Marketable securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total cash equivalents, restricted cash and marketable securities $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Reported as: Cash equivalents $ Restricted cash ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total cash equivalents, and restricted cash $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of available for sale securities continuous unrealized loss position	The following table summarizes the available-for-sale securities that were in an unrealized loss position as of December 31, 2015, having been in such a position for less than 12 months, and none having been deemed to be other-than-temporarily impaired (in thousands): Gross Unrealized Losses Estimated Fair Value U.S. government agency securities $ $
Schedule of Property and equipment	Property and equipment consisted of the following (in thousands): December 31, 2015 2014 Leasehold improvements $ $ Laboratory equipment Equipment under capital lease Computer equipment Software Furniture and fixtures Automobiles — Construction-in-progress ​ ​ ​ ​ ​ ​ ​ ​ Total property and equipment, gross Accumulated depreciation and amortization ) ) ​ ​ ​ ​ ​ ​ ​ ​ Total property and equipment, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of Accrued liabilities	Accrued liabilities consisted of the following (in thousands): Year ended December 31, 2015 2014 Accrued compensation and related expenses $ $ Accrued laboratory materials purchases — Accrued professional services Accrued costs for construction-in-progress — Other ​ ​ ​ ​ ​ ​ ​ ​ Total accrued liabilities $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Fair value measurements (Tables

Fair value measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair value measurements
Financial instruments at fair value on a recurring basis	The following tables set forth the fair value of the Company's consolidated financial instruments that were measured at fair value on a recurring basis as of December 31, 2015 and 2014 (in thousands): December 31, 2015 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ $ — $ — $ U.S. treasury notes — — U.S. government agency securities — — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total financial assets $ $ $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2014 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total financial assets $ $ — $ — $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Carrying amount and the estimated fair value of the Company's outstanding debt	The carrying amount and the estimated fair value of the Company's outstanding debt at December 31, 2015, and 2014, are as follows (in thousands): December 31, 2015 December 31, 2014 Carrying Amount Fair Value Carrying Amount Fair Value Debt $ $ $ — $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and contingencies.
Schedule of future minimum payments under operating lease	Future minimum payments under non-cancelable operating leases as of December 31, 2015 are as follows (in thousands): Year ending December 31, Amounts 2016 $ 2017 2018 2019 2020 Thereafter ​ ​ ​ ​ ​ Total minimum lease payments $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of future payments of loan agreement	Future payments under the Loan Agreement as of December 31, 2015 are as follows (in thousands): Year ending December 31, Amounts 2016 $ 2017 2018 2019 2020 Thereafter — ​ ​ ​ ​ ​ Total remaining debt payments Less: amount representing debt discount ) Less: amount representing interest ) ​ ​ ​ ​ ​ Present value of remaining debt payments Less: current portion ) ​ ​ ​ ​ ​ Total noncurrent debt obligation $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of future minimum lease payments under capital lease	Future payments under the capital lease as of December 31, 2015 are as follows (in thousands): Year ending December 31, Amounts 2016 $ 2017 2018 ​ ​ ​ ​ ​ Total capital lease obligations Less: amount representing interest ) ​ ​ ​ ​ ​ Present value of net minimum capital lease payments Less: current portion ) ​ ​ ​ ​ ​ Total noncurrent capital lease obligations $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Convertible preferred stock (Ta

Convertible preferred stock (Tables)	12 Months Ended
	Dec. 31, 2015
Convertible preferred stock
Schedule of Convertible preferred stock	Convertible preferred stock as of December 31, 2014 consisted of the following (in thousands, except share and per share data): Shares authorized Original issue price Shares issued and outstanding Aggregate liquidation amount Proceeds, net of issuance costs Series A $ $ $ Series B Series C Series D Series E Series F ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at December 31, 2014 $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Stockholders' equity (deficit)

Stockholders' equity (deficit) (Tables)	12 Months Ended
	Dec. 31, 2015
Stockholders' deficit
Schedule of shares of common stock reserved for future issuance	As of December 31, 2015 2014 Conversion of convertible preferred stock — Options issued and outstanding Options available for grant under stock option plan Shares reserved for issuance under the 2015 Employee Stock Purchase Plan — ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Stock plans (Tables)

Stock plans (Tables)	12 Months Ended
	Dec. 31, 2015
Schedule of activity under the plans	Activity under the 2010 Plan and the 2015 Plan is set forth below (in thousands, except share and per share amounts and years): Shares available for grant Stock options outstanding Weighted- average exercise price Weighted- average remaining contractual life (years) Aggregate intrinsic value Balances at December 31, 2013 $ $ Additional shares reserved — — Repurchase of unvested early exercise shares — — Options granted ) Options cancelled ) Options exercised — ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at December 31, 2014 $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additional shares reserved — Options granted ) Options cancelled ) Options exercised — ) Restricted stock units granted ) — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at December 31, 2015 $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options exercisable at December 31, 2015 $ $ Options vested and expected to vest at December 31, 2015 $ $
Summary of RSU activity	Number of Shares Weighted- Average Grant Date Fair Value Balance at December 31, 2014 — $ — RSUs granted RSUs vested — — RSUs cancelled ) ​ ​ ​ ​ ​ ​ ​ ​ Balance at December 31, 2015 $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Summary of stock based compensation expense related to stock options included in the condensed consolidated statements of operations	The following table summarizes stock-based compensation expense for the years ended December 31, 2015, 2014 and 2013 included in the statements of operations and comprehensive loss as follows (in thousands): Year ended December 31, 2015 2014 2013 Cost of revenue $ $ $ Research and development Selling and marketing General and administrative ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total stock-based compensation expense $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
ESPP
Schedule of assumptions used in determination of fair value of options using Black Scholes model	Year ended December 31, 2015 Expected term (in years) Expected volatility % Risk-free interest rate % Dividend yield —
Options
Schedule of assumptions used in determination of fair value of options using Black Scholes model	Year ended December 31, 2015 2014 2013 Expected term (in years) 6.03 6.03 6.03 Expected volatility 68.2 - 79.7% 83.8 - 86.6% 88.5 - 94.5% Risk-free interest rate 1.28 - 1.86% 1.53 - 1.91% 0.99 - 1.97% Dividend yield — — —
Non-Employee Options
Schedule of assumptions used in determination of fair value of options using Black Scholes model	Year ended December 31, 2015 2014 2013 Expected term (in years) 7.25 - 9.82 9.37 - 9.40 9.25 - 9.60 Expected volatility 69.9 - 78.7% 83.8% 88.5% Risk-free interest rate 1.86 - 2.25% 1.99 - 2.41% 2.85 - 2.94% Dividend yield — — —

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income taxes
Schedule of components of loss before income taxes by U.S. and foreign jurisdictions	The components of loss before income taxes by U.S. and foreign jurisdictions are as follows (in thousands): Year ended December 31, 2015 2014 2013 United States $ $ $ Foreign ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of reconciliation of the tax expense computed at the statutory federal rate and Company's tax expense	Year ended December 31, 2015 2014 2013 U.S. federal taxes at statutory rate % % % State taxes (net of federal benefit) Non-deductible expenses ) ) ) Foreign tax differential ) ) ) Change in valuation allowance ) ) ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total % % %
Schedule of net deferred tax assets	The tax effects of temporary differences and carryforwards that give rise to significant portions of the deferred tax assets are as follows (in thousands): As of December 31, 2015 2014 Deferred tax assets: Net operating loss carryforwards $ $ Tax credits Accruals and other ​ ​ ​ ​ ​ ​ ​ ​ Gross deferred tax assets Valuation allowance ) ) ​ ​ ​ ​ ​ ​ ​ ​ Net deferred tax assets Deferred tax liabilities: Property and equipment $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ Total deferred tax liabilities ) ) ​ ​ ​ ​ ​ ​ ​ ​ Net deferred tax assets $ — $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of reconciliation of gross unrecognized tax benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Year ended December 31, 2015 2014 2013 Unrecognized tax benefits, beginning of period $ $ $ Gross increases—current period tax positions Gross increases—prior period tax positions — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unrecognized tax benefits, end of period $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Net loss per common share (Tabl

Net loss per common share (Tables)	12 Months Ended
	Dec. 31, 2015
Net loss per share attributable to common stockholders
Schedule of Earnings per share, basic and diluted	The following table presents the calculation of basic and diluted net loss per share attributable to common stockholders for the years ended December 31, 2015, 2014 and 2013 (in thousands, except share and per share amounts): Year ended December 31, 2015 2014 2013 Net loss $ ) $ ) $ ) Less: dividends on convertible preferred stock — — ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to common stockholders $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shares used in computing net loss per share attributable to common stockholders, basic and diluted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss per share attributable to common stockholders, basic and diluted $ ) $ ) $ ) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of Antidilutive securities excluded from computation of earnings per share	Year ended December 31, 2015 2014 2013 Shares of common stock subject to outstanding options Shares of common stock subject to outstanding restricted stock unit awards — — Shares of common stock pursuant to employee stock purchase plan — — Shares of common stock subject to conversion of preferred stock — Shares of common stock subject to unvested early exercise of outstanding options subject to repurchase ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total shares of common stock equivalents ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Geographic information (Tables)

Geographic information (Tables)	12 Months Ended
	Dec. 31, 2015
Geographic information
Schedule of Revenue by country	Revenue by country is determined based on the billing address of the customer. The following presents revenue by country for December 31, 2015, 2014 and 2013 (in thousands): December 31, 2015 2014 2013 United States $ $ $ Israel Canada Rest of world ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue $ $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of long-lived assets by location	Long-lived assets (net) by location are summarized as follows (in thousands): December 31, 2015 2014 United States $ $ Chile ​ ​ ​ ​ ​ ​ ​ ​ Total long-lived assets, net $ $ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Selected Quarterly Data (Unau33

Selected Quarterly Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Selected Quarterly Data (Unaudited)
Schedule of selected quarterly data	Three months ended (In thousands, except per share amounts) Dec 31, 2015 Sept 30, 2015 June 30, 2015 Mar 31, 2015 Dec 31, 2014 Sept 30, 2014 June 30, 2014 Mar 31, 2014 Revenue $ $ $ $ $ $ $ $ Loss from operations $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ ) Net loss $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ ) Net loss attributable to common stockholders $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ ) Net loss per share attributable to common stockholders, basic and diluted $ ) $ ) $ ) $ ) $ ) $ ) $ ) $ )

Organization and description 34

Organization and description of business (Details) $ / shares in Units, $ in Millions	Feb. 12, 2015USD ($)$ / sharesshares	Feb. 28, 2015shares	Dec. 31, 2015segment$ / sharesshares	Dec. 31, 2014$ / sharesshares
Number of operating segments | segment			1
Number of common stock shares issued			31,935,121	944,581
Number of common stock shares converted from preferred stock		23,521,889
Shares authorized	420,000,000
Common stock, shares authorized			400,000,000	160,131,524
Preferred stock, authorized shares			20,000,000	0
Common stock, par value (in dollars per share) | $ / shares	$ 0.0001		$ 0.0001	$ 0.0001
Preferred stock, par value (in dollars per share) | $ / shares			$ 0.0001	$ 0.0001
Preferred stock, shares outstanding			0	0
IPO
Number of common stock shares issued	7,302,500
Sale price on common stock (in dollars per share) | $ / shares	$ 16
Net proceeds from issue of common stock | $	$ 105.7
Preferred stock, par value (in dollars per share) | $ / shares	$ 0.0001
Common stock
Number of common stock shares converted from preferred stock			23,521,889
Common stock, shares authorized	400,000,000
Preferred Stock
Preferred stock, authorized shares	20,000,000
Maximum | Common stock | IPO
Number additional shares on common stock can be purchased by underwriters		952,500

Summary of significant accoun35

Summary of significant accounting policies - Concentrations of credit risk (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Customer A
Concentration risk (as a percent)			44.00%
Customer A | Maximum
Concentration risk (as a percent)	10.00%	10.00%
Customer B
Concentration risk (as a percent)		15.00%
Customer B | Maximum
Concentration risk (as a percent)	10.00%
Customer C
Concentration risk (as a percent)	13.00%
Customer C | Maximum
Concentration risk (as a percent)		10.00%	10.00%
Revenue | Customer Concentration Risk
Concentration risk (as a percent)	10.00%

Summary of significant accoun36

Summary of significant accounting policies - Internal-use software , Property and equipment (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Internal-use software development costs incurred and capitalized	$ 1,500,000	$ 550,000	$ 250,000
Internal-use software amortization	718,000	152,000	$ 0
Carrying value of capitalized software	$ 1,400,000	648,000
Weighted average useful life of internal-use software	13 months
Deferred offering costs		$ 1,900,000
Shares subject to repurchase, excluded from basic loss per share calculation	4,193,153	25,469,124	14,749,326
Furniture and fixtures
Useful lives	7 years
Automobiles
Useful lives	7 years
Laboratory equipment
Useful lives	5 years
Computer equipment
Useful lives	3 years
Software
Useful lives	3 years
Unvested early exercise of outstanding options subject to repurchase
Shares subject to repurchase, excluded from basic loss per share calculation	4,659	23,903	54,407

Balance sheet components - Cash

Balance sheet components - Cash equivalents and marketable securities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)item	Dec. 31, 2014USD ($)
Investment Holdings
Amortized Cost	$ 109,590
Gross Unrealized Gains	1
Gross Unrealized Losses	(16)
Estimated Fair Value	109,575	$ 15,167
Reported as:
Cash equivalents	50,964	15,017
Restricted cash	4,831	150
Marketable securities	53,780
Estimated Fair Value	$ 109,575	15,167
Available-for-sale Securities, Continuous Unrealized Loss Position
Number of securities that are in continuous unrealized loss position for more than one year | item	0
Remaining contractual maturities	1 year
Marketable available-for-sale securities		0
Money market funds
Investment Holdings
Amortized Cost	$ 39,998	15,167
Estimated Fair Value	39,998	15,167
Reported as:
Estimated Fair Value	39,998	$ 15,167
U.S. treasury notes
Investment Holdings
Amortized Cost	4,006
Estimated Fair Value	4,006
Reported as:
Estimated Fair Value	4,006
US government agency securities
Investment Holdings
Amortized Cost	65,586
Gross Unrealized Gains	1
Gross Unrealized Losses	(16)
Estimated Fair Value	65,571
Reported as:
Estimated Fair Value	65,571
Available-for-sale Securities, Continuous Unrealized Loss Position
Gross Unrealized Losses for less than 12 months	16
Estimated Fair Value for less than 12 months	$ 42,034

Balance sheet components - Prop

Balance sheet components - Property and equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property and equipment
Total property and equipment, gross	$ 27,430	$ 19,175
Accumulated depreciation and amortization	(8,721)	(3,503)
Total property and equipment, net	18,709	15,672
Capital lease equipment not placed in service		2,900
Depreciation and amortization	5,321	2,315	$ 928
Leasehold improvements
Property and equipment
Total property and equipment, gross	2,548	1,914
Laboratory equipment
Property and equipment
Total property and equipment, gross	10,461	6,528
Equipment under capital lease
Property and equipment
Total property and equipment, gross	8,224	3,735
Computer equipment
Property and equipment
Total property and equipment, gross	2,397	1,156
Software
Property and equipment
Total property and equipment, gross	2,368	831
Furniture and fixtures
Property and equipment
Total property and equipment, gross	210	158
Automobiles
Property and equipment
Total property and equipment, gross	20
Construction-in-progress
Property and equipment
Total property and equipment, gross	$ 1,202	$ 4,853

Balance sheet components - Accr

Balance sheet components - Accrued liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accrued liabilities
Accrued compensation and related expenses	$ 2,307	$ 1,439
Accrued laboratory materials purchases	426
Accrued professional services	272	1,030
Accrued costs for construction-in-progress		32
Other	1,248	736
Total accrued liabilities	$ 4,253	$ 3,237

Fair value measurements (Detail

Fair value measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Total financial assets	$ 109,575	$ 15,167
Transfers from Level 1 to Level 2	0	0
Transfers from Level 2 to Level 1	0	0
Cash and Cash Equivalents, at Carrying Value	73,238	107,027	$ 43,070	$ 21,801
Recurring basis
Total financial assets	109,575	15,167
Recurring basis | Level 1
Total financial assets	44,004	$ 15,167
Recurring basis | Level 2
Total financial assets	65,571
Recurring basis | Level 2 | Carrying Amount
Debt	7,040
Recurring basis | Level 2 | Fair Value
Debt	6,952
Money market funds | Recurring basis
Total financial assets	39,998
Money market funds | Recurring basis | Level 1
Total financial assets	39,998
U.S. treasury notes
Total financial assets	4,006
U.S. treasury notes | Recurring basis
Total financial assets	4,006
U.S. treasury notes | Recurring basis | Level 1
Total financial assets	4,006
US government agency securities
Total financial assets	65,571
US government agency securities | Recurring basis
Total financial assets	65,571
US government agency securities | Recurring basis | Level 2
Total financial assets	$ 65,571

Commitments and contingencies -

Commitments and contingencies - Operating Leases (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Future minimum lease payments under operating leases
2,016		$ 6,224
2,017		7,366
2,018		7,269
2,019		7,463
2,020		7,068
Thereafter		44,374
Total minimum lease payments		79,764
Rent expense		3,700	$ 1,400	$ 800
Office Facility In San Francisco | New Leases
Additional term of lease	10 years
Lease term	10 years
Security Deposit	$ 4,600
Lease incentive in form of lease improvements	$ 5,200
Incentive utilized		0
Future minimum lease payments under operating leases
Total minimum lease payments		72,000
Other Noncurrent Assets [Member]
Security Deposit		$ 1,500	$ 1,400

Commitments and contingencies42

Commitments and contingencies - Equipment Financing (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jul. 31, 2015	Dec. 31, 2015
Future payments under the Loan Agreement
Less: current portion		$ (1,536,000)
Total noncurrent debt obligation		5,504,000
Loan and Security Agreement | Secured Debt
Maximum borrowing capacity	$ 15,000,000
Obligations under Loan Agreement		7,000,000
Debt issuance cost		47,000
Future payments under the Loan Agreement
2,016		1,741,000
2,017		1,697,000
2,018		1,649,000
2,019		1,600,000
2,020		911,000
Total remaining debt payments		7,598,000
Less: amount representing debt discount		(44,000)
Less amount representing interest		(514,000)
Present value of remaining debt payments		7,040,000
Less: current portion		(1,536,000)
Total noncurrent debt obligation		$ 5,504,000
Loan and Security Agreement | Initial Tranche
Maximum borrowing capacity	2,500,000
Loan and Security Agreement | Other Tranches
Maximum borrowing capacity	$ 2,000,000
Loan and Security Agreement | Prime Rate | Secured Debt
Basis reduction on variable rate (as a percent)	0.25%

Commitments and Contingencies43

Commitments and Contingencies - Capital Lease (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Future payments under the capital lease
Lease term	3 years
2,016	$ 1,692,000
2,017	1,350,000
2,018	269,000
Total capital lease obligation	3,311,000
Less: amount representing interest	(147,000)
Present value of net minimum capital lease payments	3,164,000
Less: current portion	(1,588,000)	$ (1,524,000)
Total noncurrent capital lease obligation	1,576,000	2,011,000
Interest expense	141,000,000	61,000	$ 59,000,000
Property and equipment under capital lease	8,200,000	6,600,000
Capital lease equipment not placed in service		2,900,000
Accumulated depreciation and amortization	$ 2,800,000	$ 1,400,000
Minimum
Future payments under the capital lease
Interest rate (as a percent)	3.80%
Maximum
Future payments under the capital lease
Interest rate (as a percent)	4.30%

Convertible preferred stock (De

Convertible preferred stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended		48 Months Ended
	Feb. 28, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2015
Convertible preferred stock
Shares authorized		141,131,524		141,131,524	0
Issuance of convertible preferred stock, net of issuance costs (in shares)		141,131,524		141,131,524	0
Shares outstanding		141,131,524		141,131,524	0
Aggregate liquidation amount		$ 207,002		$ 207,002
Proceeds, net of issuance costs		$ 115,731	$ 49,819	$ 202,305
Number of common stock shares converted from preferred stock	23,521,889
Series A convertible preferred stock
Convertible preferred stock
Shares authorized		11,693,179		11,693,179
Original issue price		$ 0.44		$ 0.44
Issuance of convertible preferred stock, net of issuance costs (in shares)		11,693,179		11,693,179
Shares outstanding		11,693,179		11,693,179
Aggregate liquidation amount		$ 5,145		$ 5,145
Proceeds, net of issuance costs		$ 5,109
Series B convertible preferred stock
Convertible preferred stock
Shares authorized		4,181,818		4,181,818
Original issue price		$ 0.55		$ 0.55
Issuance of convertible preferred stock, net of issuance costs (in shares)		4,181,818		4,181,818
Shares outstanding		4,181,818		4,181,818
Aggregate liquidation amount		$ 2,300		$ 2,300
Proceeds, net of issuance costs		$ 2,253
Series C convertible preferred stock
Convertible preferred stock
Shares authorized		31,112,750		31,112,750
Original issue price		$ 0.95		$ 0.95
Issuance of convertible preferred stock, net of issuance costs (in shares)		31,112,750		31,112,750
Shares outstanding		31,112,750		31,112,750
Aggregate liquidation amount		$ 29,557		$ 29,557
Proceeds, net of issuance costs		$ 29,393
Series D convertible preferred stock
Convertible preferred stock
Shares authorized		8,000,000		8,000,000
Original issue price		$ 1.25	$ 1.25	$ 1.25
Issuance of convertible preferred stock, net of issuance costs (in shares)		8,000,000	8,000,000	8,000,000
Shares outstanding		8,000,000		8,000,000
Aggregate liquidation amount		$ 10,000		$ 10,000
Proceeds, net of issuance costs		$ 9,933
Series E convertible preferred stock
Convertible preferred stock
Shares authorized		26,143,777		26,143,777
Original issue price		$ 1.53	$ 1.53	$ 1.53
Issuance of convertible preferred stock, net of issuance costs (in shares)		26,143,777	26,143,777	26,143,777
Shares outstanding		26,143,777		26,143,777
Aggregate liquidation amount		$ 40,000		$ 40,000
Proceeds, net of issuance costs		$ 39,886
Series F convertible preferred stock
Convertible preferred stock
Shares authorized		60,000,000		60,000,000
Original issue price		$ 2		$ 2
Issuance of convertible preferred stock, net of issuance costs (in shares)		60,000,000		60,000,000
Shares outstanding		60,000,000		60,000,000
Aggregate liquidation amount		$ 120,000		$ 120,000
Proceeds, net of issuance costs		$ 115,731

Stockholders' equity (deficit45

Stockholders' equity (deficit) (Details)	12 Months Ended
	Dec. 31, 2015Voteshares	Jan. 31, 2015shares	Dec. 31, 2014shares
Class of Stock
Common stock reserved for future issuance	6,253,651		25,722,026
Options issued and outstanding	3,659,713		1,923,332
Options available for grant under stock option plan	2,268,938		276,805
ESPP
Class of Stock
Common stock reserved for future issuance	325,000	325,000
Convertible preferred stock
Class of Stock
Common stock reserved for future issuance			23,521,889
Common stock
Class of Stock
Number of votes for each share | Vote	1

Stock plans - Stock incentive p

Stock plans - Stock incentive plans (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Activity under the plan
Shares available for grant		2,268,938	276,805
Additional shares reserved		6,253,651	25,722,026
Balance at the beginning of the period	1,923,332	1,923,332
Balance at the end of the period		3,659,713	1,923,332
Restricted stock units
Stock incentive plan
Vesting period		3 years
Activity under the plan
Units granted		(493,068)
Vested and expected to vest
Weighted-average grant date fair value (in dollars per share)		$ 10.72	$ 0	$ 0
Restricted stock units | First anniversary
Stock incentive plan
Vesting rate upon anniversaries (as a percent)		33.33%
Restricted stock units | Second anniversary
Stock incentive plan
Vesting rate upon anniversaries (as a percent)		33.33%
Restricted stock units | Third anniversary
Stock incentive plan
Vesting rate upon anniversaries (as a percent)		33.33%
Stock incentive plans
Stock incentive plan
Vesting period		4 years
Vesting rate upon anniversaries (as a percent)		25.00%
Monthly vesting rate thereafter (as a percent)		2.08%
Activity under the plan
Additional shares reserved	120,452		4,370,452
Stock incentive plans | Minimum
Stock incentive plan
Employees holding voting rights of all classes of stock (as a percent)		10.00%
Exercise price of options on common stock (as a percent)		110.00%
Stock incentive plans | Maximum
Stock incentive plan
Term of options granted		10 years
Stock incentive plans | Options
Activity under the plan
Shares available for grant		2,268,938	276,805	873,233
Additional shares reserved		4,370,452	333,333
Repurchase of unvested early exercise shares			1,959
Balance at the beginning of the period	1,923,332	1,923,332	1,173,019
Options granted (in shares)		2,103,304	1,164,990
Option cancelled (in shares)		(218,053)	(233,270)
Options exercised (in shares)		(148,870)	(181,407)
Balance at the end of the period		3,659,713	1,923,332	1,173,019
Weighted-average exercise price
Balance at the beginning of the period (in dollars per share)	$ 4.37	$ 4.37	$ 1.40
Options granted (in dollars per share)		9.78	6.21
Options cancelled (in dollars per share)		7.73	2.07
Options exercised (in dollars per share)		1.98	1.15
Balance at the end of the period (in dollars per share)		$ 7.38	$ 4.37	$ 1.40
Additional information
Weighted-average remaining contractual life		8 years 10 months 21 days	8 years 10 months 24 days	9 years
Aggregate intrinsic value		$ 7,099,000	$ 15,946,000	$ 2,155,000
Exercisable, Number of shares		833,787
Exercisable, weighted-average exercise price (in dollars per share)		$ 3.54
Exercisable, weighted-average remaining contractual life		7 years 6 months 26 days
Exercisable, aggregate intrinsic value		$ 4,054,000
Vested and expected to vest
Number of shares		3,553,680
Weighted-average exercise price (in dollars per share)		$ 7.33
Weighted-average remaining contractual life		8 years 10 months 13 days
Aggregate intrinsic value		$ 7,017,000
Weighted-average grant date fair value (in dollars per share)		$ 6.26	$ 4.68	$ 1.83
Fair value of options granted		$ 2,128,000	$ 494,000	$ 204,000
Exercised, aggregate intrinsic value		$ 1,285,000	$ 644,000	$ 60,000
Stock incentive plans | Restricted stock units
Activity under the plan
Units granted		(493,068)
ESPP
Stock incentive plan
Purchase price of common stock of the lesser of fair market value on the purchase date or the last trading day preceding the offering date (as a percent)	85.00%
Activity under the plan
Additional shares reserved	325,000	325,000
Vested and expected to vest
Weighted-average grant date fair value (in dollars per share)		$ 2.17

Stock plans - RSU Activity (Det

Stock plans - RSU Activity (Details) - Restricted stock units	12 Months Ended
	Dec. 31, 2015$ / sharesshares
Number of shares
Granted (in shares) | shares	493,068
Cancelled (in shares) | shares	(10,250)
Balance at the end of the period (in shares) | shares	482,818
Weighted-Average Grant Date Fair Value
Granted (in dollars per share) | $ / shares	$ 10.72
Cancelled (in dollars per share) | $ / shares	10.94
Balance at the end of the period (in dollars per share) | $ / shares	$ 10.71

Stock plans - Risk free interes

Stock plans - Risk free interest rate & Dividend yield (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Stock-based compensation	$ 3,477,000	$ 971,000	$ 260,000
ESPP
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Expected term (in years)	6 months
Expected volatility	74.13%
Risk-free interest rate	0.33%
Weighted-average grant date fair value (in dollars per share)	$ 2.17
Stock-based compensation	$ 102,000
Number of shares purchased	0
Cash received from payroll deductions	$ 259,000
Non Employees
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Expected volatility		83.80%	88.50%
Minimum | Non-Employee Options
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Expected volatility	68.20%	83.80%	88.50%
Risk-free interest rate	1.28%	1.53%	0.99%
Minimum | Non Employees
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Expected term (in years)	7 years 3 months	9 years 4 months 13 days	9 years 3 months
Expected volatility	69.90%
Risk-free interest rate	1.86%	1.99%	2.85%
Maximum | Non-Employee Options
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Expected term (in years)	6 years 11 days	6 years 11 days	6 years 11 days
Expected volatility	79.70%	86.60%	94.50%
Risk-free interest rate	1.86%	1.91%	1.97%
Maximum | Non Employees
Assumptions used in determination of fair value of options using the Black Scholes option pricing valuation model
Expected term (in years)	9 years 9 months 26 days	9 years 4 months 24 days	9 years 7 months 6 days
Expected volatility	78.70%
Risk-free interest rate	2.25%	2.41%	2.94%

Stock plans - Stock-based compe

Stock plans - Stock-based compensation expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock-based compensation
Total stock based compensation expense	$ 3,477,000	$ 971,000	$ 260,000
Unrecognized stock based compensation	$ 14,600,000
Expected period to recognize on a straight line basis	3 years 3 months 18 days
Capitalized stock-based employee compensation	$ 0
Restricted stock units
Stock-based compensation
Unrecognized stock based compensation	$ 4,600,000
Expected period to recognize on a straight line basis	2 years 8 months 12 days
Cost of revenue.
Stock-based compensation
Total stock based compensation expense	$ 368,000	102,000	11,000
Research and development
Stock-based compensation
Total stock based compensation expense	1,545,000	382,000	165,000
Selling and marketing
Stock-based compensation
Total stock based compensation expense	688,000	216,000	42,000
General and administrative
Stock-based compensation
Total stock based compensation expense	$ 876,000	$ 271,000	$ 42,000

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Components of loss before income taxes
United States									$ (88,112)	$ (46,328)	$ (23,522)
Foreign									(1,670)	(1,164)	(1,316)
Net loss	$ (24,360)	$ (22,527)	$ (24,258)	$ (18,637)	$ (15,305)	$ (12,615)	$ (10,539)	$ (9,033)	$ (89,782)	$ (47,492)	$ (24,838)
Reconciliation of the tax expense computed at the statutory federal rate and Company's tax expense
U.S. federal taxes at statutory rate									34.00%	34.00%	34.00%
State taxes (net of federal benefit)									0.80%	0.70%	0.90%
Non-deductible expenses									0.80%	0.70%	0.40%
Foreign tax differential									0.20%	0.80%	1.80%
Change in valuation allowance									33.80%	33.20%	32.70%
Total									0.00%	0.00%	0.00%
Deferred tax assets:
Net operating loss carryforwards	53,123				28,022				$ 53,123	$ 28,022
Tax credits	13				13				13	13
Accruals and other	7,612				1,914				7,612	1,914
Gross deferred tax assets	60,748				29,949				60,748	29,949
Valuation allowance	(60,304)				(29,498)				(60,304)	(29,498)
Net deferred tax assets	444				451				444	451
Deferred tax liabilities:
Property and equipment	(444)				(451)				(444)	(451)
Total deferred tax liabilities	$ (444)				$ (451)				$ (444)	$ (451)

Income Taxes - Unrecognized tax

Income Taxes - Unrecognized tax benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Increase in valuation allowance	$ 30,800,000	$ 16,100,000
Tax credit carryforwards		18,000
Reconciliation of unrecognized tax benefits
Unrecognized tax benefits, beginning of period	5,661,000	2,100,000	$ 618,000
Gross increases-current period tax positions	2,993,000	1,874,000	1,482,000
Gross increases-prior period tax positions	2,775,000	1,687,000
Unrecognized tax benefits, end of period	11,429,000	5,661,000	$ 2,100,000
Interest and penalties related to unrecongnized tax benefits	0
Foreign
Net operating loss carryforwards		4,000,000
Options
Net operating loss carryforwards	500,000
Federal
Net operating loss carryforwards	$ 147,000,000
Reconciliation of unrecognized tax benefits
Number of tax years open for examination	3 years
Federal | Research and development
Tax credit carryforwards		3,700,000
California
Net operating loss carryforwards	$ 96,000,000
Reconciliation of unrecognized tax benefits
Number of tax years open for examination	4 years
California | Research and development
Tax credit carryforwards		$ 3,300,000

Net loss per share attributab52

Net loss per share attributable to common stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net loss per share
Net loss	$ (24,360)	$ (22,527)	$ (24,258)	$ (18,637)	$ (15,305)	$ (12,615)	$ (10,539)	$ (9,033)	$ (89,782)	$ (47,492)	$ (24,838)
Less: dividends on convertible preferred stock											(151)
Net loss attributable to common stockholders	$ (24,360)	$ (22,527)	$ (24,258)	$ (18,637)	$ (15,305)	$ (12,615)	$ (10,539)	$ (9,033)	$ (89,782)	$ (47,492)	$ (24,989)
Shares used in computing net loss per share attributable to common stockholders, basic and diluted									28,213,324	846,027	691,731
Net loss per share, basic and diluted	$ (0.76)	$ (0.71)	$ (0.76)	$ (1.09)	$ (16.56)	$ (14.24)	$ (12.81)	$ (12.06)	$ (3.18)	$ (56.14)	$ (36.13)
Antidilutive shares excluded from diluted net loss per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									4,193,153	25,469,124	14,749,326
Options
Antidilutive shares excluded from diluted net loss per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									3,659,713	1,923,332	1,173,019
Restricted stock units
Antidilutive shares excluded from diluted net loss per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									482,818
ESPP
Antidilutive shares excluded from diluted net loss per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									45,963
Convertible preferred stock
Antidilutive shares excluded from diluted net loss per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount										23,521,889	13,521,900
Unvested early exercise of outstanding options subject to repurchase
Antidilutive shares excluded from diluted net loss per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									4,659	23,903	54,407

Geographic information (Details

Geographic information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Geographic information
Revenue	$ 8,378	$ 1,604	$ 148
Total Long-lived assets, net	18,709	15,672
United States
Geographic information
Revenue	5,432	1,067	62
Total Long-lived assets, net	17,180	13,858
Israel
Geographic information
Revenue	175	109	65
Canada
Geographic information
Revenue	2,112	310	2
Rest of World
Geographic information
Revenue	659	118	$ 19
Chile
Geographic information
Total Long-lived assets, net	$ 1,529	$ 1,814

Selected Quarterly Data (Unau54

Selected Quarterly Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly financial information
Revenue	$ 3,161	$ 2,187	$ 1,801	$ 1,229	$ 875	$ 310	$ 301	$ 118
Loss from operations	(24,291)	(22,456)	(24,125)	(18,605)	(15,283)	(12,534)	(10,516)	(9,019)	$ (89,477)	$ (47,352)	$ (24,753)
Net loss	(24,360)	(22,527)	(24,258)	(18,637)	(15,305)	(12,615)	(10,539)	(9,033)	(89,782)	(47,492)	(24,838)
Net loss attributable to common stockholders	$ (24,360)	$ (22,527)	$ (24,258)	$ (18,637)	$ (15,305)	$ (12,615)	$ (10,539)	$ (9,033)	$ (89,782)	$ (47,492)	$ (24,989)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.76)	$ (0.71)	$ (0.76)	$ (1.09)	$ (16.56)	$ (14.24)	$ (12.81)	$ (12.06)	$ (3.18)	$ (56.14)	$ (36.13)