Rockley Photonics (RKLYQ) 10-Q 15 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Nov. 08, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-40735
Entity Registrant Name	Rockley Photonics Holdings Limited
Entity Incorporation, State or Country Code	E9
Entity Address, Address Line One	3rd Floor
Entity Address, Address Line Two	1 Ashley Road
Entity Address, City or Town	Altrincham
Entity Address, Country	GB
Entity Address, Postal Zip Code	WA14 2DT
Country Region	+44
City Area Code	1865
Local Phone Number	292017
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		127,031,025
Entity Central Index Key	0001852117
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Ordinary Shares
Document Information [Line Items]
Title of 12(b) Security	Ordinary shares, $0.000004026575398 par value per share
Trading Symbol	RKLY
Security Exchange Name	NYSE
Warrants
Document Information [Line Items]
Title of 12(b) Security	Warrants, each whole warrant exercisable for one ordinary share at an exercise price of $11.50 per share
Trading Symbol	RKLY.WS
Security Exchange Name	NYSE

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Statement) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 75,191	$ 19,228
Short-term investments, at fair value	29,317	0
Accounts receivable	1,516	4,925
Other receivables	24,966	18,024
Prepaid expenses	9,815	1,605
Other current assets	4	609
Total current assets	140,809	44,391
Long-term investments, at fair value	20,485	0
Property, equipment, net	9,358	6,182
Equity method investment	4,856	5,202
Intangible assets, net	3,048	3,048
Other non-current assets	3,069	1,607
Total assets	181,625	60,430
Current liabilities
Trade payables	6,266	4,413
Accrued expenses	16,121	10,395
Debt, current portion	28,590	0
Other current liabilities	923	998
Total current liabilities	51,900	15,806
Long-term debt, net of current portion	0	74,804
Warrant liabilities	13,789	0
Other long-term liabilities	2,442	1,127
Total liabilities	68,131	91,737
Commitments and contingencies (Note 15)
Shareholders’ equity (deficit)
Ordinary shares, $0.000004 par value; 12,417,500,000 and 139,033,366 authorized as of September 30, 2021 and December 31, 2020, respectively; 126,675,098 and 83,539,382 issued and outstanding as of September 30, 2021 and December 31, 2020, respectively	0	0
Additional paid-in-capital	499,683	201,576
Accumulated deficit	(386,189)	(232,883)
Total shareholders’ equity (deficit)	113,494	(31,307)
Total liabilities and shareholders’ equity (deficit)	$ 181,625	$ 60,430

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2021	Aug. 11, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Ordinary shares, par value (in dollars per share)	$ 0.000004
Ordinary shares authorized (in shares)	12,417,500,000		139,033,366
Ordinary shares issued (in shares)	126,675,098		83,539,382
Ordinary shares outstanding (in shares)	126,675,098	126,675,000	83,539,382

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenue	$ 1,839	$ 4,517	$ 5,805	$ 19,061
Cost of revenue	3,459	5,015	11,742	18,100
Gross profit	(1,620)	(498)	(5,937)	961
Operating expenses:
Selling, general, and administrative expenses	13,568	5,354	27,588	12,603
Research and development expenses	26,418	10,790	59,949	27,007
Total operating expenses	39,986	16,144	87,537	39,610
Loss from operations	(41,606)	(16,642)	(93,474)	(38,649)
Other income (expense):
Forgiveness of Paycheck Protection Program loan	0	0	2,860	0
Interest expense, net	(1,587)	1	(1,913)	(73)
Equity method investment loss	40	(689)	(720)	(941)
Change in fair value of debt instruments	(14,255)	(3,325)	(59,916)	(5,547)
Change in fair value of warrant liabilities	515	0	515	0
Gain (loss) on foreign currency	(481)	285	150	(1,369)
Total other income (expense)	(15,768)	(3,728)	(59,024)	(7,930)
Loss before income taxes	(57,374)	(20,370)	(152,498)	(46,579)
Provision for income tax	598	154	808	374
Net loss and comprehensive loss	(57,972)	(20,524)	(153,306)	(46,953)
Comprehensive loss	$ (57,972)	$ (20,524)	$ (153,306)	$ (46,953)
Net loss per share:
Basic (in dollars per share)	$ (0.54)	$ (0.25)	$ (1.67)	$ (0.56)
Diluted (in dollars per share)	$ (0.54)	$ (0.25)	$ (1.67)	$ (0.56)
Weighted-average shares outstanding:
Basic (in shares)	107,633,037	83,509,920	92,008,435	83,392,042
Diluted (in shares)	107,633,037	83,509,920	92,008,435	83,392,042

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Shareholders’ Equity (Deficit) - USD ($) $ in Thousands	Total	SC Health	SC Health Sponsor	Ordinary Shares	Ordinary SharesSC Health	Ordinary SharesSC Health Sponsor	Ordinary Shares and Additional Paid-in Capital	Ordinary Shares and Additional Paid-in CapitalSC Health	Ordinary Shares and Additional Paid-in CapitalSC Health Sponsor	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2019				82,792,725
Beginning balance at Dec. 31, 2019	$ 36,259						$ 188,865			$ (152,606)
Increase (Decrease) in Stockholders' Equity
Net loss	(16,426)									(16,426)
Exercise of stock options (in shares)				9,263
Exercise of stock options	20						20
Exercise of warrants (in shares)				13,717
Exercise of warrants	7						7
Stock-based compensation	1,644						1,644
Ordinary share issuance, net of issuance costs (in shares)				366,147
Ordinary share issuance, net of issuance costs	2,087						2,087
Ending balance (in shares) at Mar. 31, 2020				83,181,852
Ending balance at Mar. 31, 2020	23,591						192,623			(169,032)
Beginning balance (in shares) at Dec. 31, 2019				82,792,725
Beginning balance at Dec. 31, 2019	36,259						188,865			(152,606)
Increase (Decrease) in Stockholders' Equity
Net loss	(46,953)
Ending balance (in shares) at Sep. 30, 2020				83,181,852
Ending balance at Sep. 30, 2020	(2,840)						196,719			(199,559)
Beginning balance (in shares) at Mar. 31, 2020				83,181,852
Beginning balance at Mar. 31, 2020	23,591						192,623			(169,032)
Increase (Decrease) in Stockholders' Equity
Net loss	(10,003)									(10,003)
Stock-based compensation	2,545						2,545
Ordinary share issuance, net of issuance costs	(126)						(126)
Ending balance (in shares) at Jun. 30, 2020				83,181,852
Ending balance at Jun. 30, 2020	16,007						195,042			(179,035)
Increase (Decrease) in Stockholders' Equity
Net loss	(20,524)									(20,524)
Stock-based compensation	1,677						1,677
Ordinary share issuance, net of issuance costs	0						0
Ending balance (in shares) at Sep. 30, 2020				83,181,852
Ending balance at Sep. 30, 2020	(2,840)						196,719			(199,559)
Beginning balance (in shares) at Dec. 31, 2020				83,539,382
Beginning balance at Dec. 31, 2020	(31,307)						201,576			(232,883)
Increase (Decrease) in Stockholders' Equity
Net loss	(64,777)									(64,777)
Exercise of stock options (in shares)				216,670
Exercise of stock options	137						137
Exercise of warrants (in shares)				57,811
Issuance of warrants	263						263
Stock-based compensation	1,725						1,725
Ending balance (in shares) at Mar. 31, 2021				83,813,863
Ending balance at Mar. 31, 2021	(93,959)						203,701			(297,660)
Beginning balance (in shares) at Dec. 31, 2020				83,539,382
Beginning balance at Dec. 31, 2020	(31,307)						201,576			(232,883)
Increase (Decrease) in Stockholders' Equity
Net loss	(153,306)
Ending balance (in shares) at Sep. 30, 2021				126,675,098
Ending balance at Sep. 30, 2021	113,494						499,683			(386,189)
Beginning balance (in shares) at Mar. 31, 2021				83,813,863
Beginning balance at Mar. 31, 2021	(93,959)						203,701			(297,660)
Increase (Decrease) in Stockholders' Equity
Net loss	(30,557)									(30,557)
Exercise of stock options (in shares)				192,064
Exercise of stock options	146						146
Stock-based compensation	1,976						1,976
Ending balance (in shares) at Jun. 30, 2021				84,005,927
Ending balance at Jun. 30, 2021	(122,394)						205,823			(328,217)
Increase (Decrease) in Stockholders' Equity
Net loss	(57,972)									(57,972)
Exercise of stock options (in shares)				57,123
Exercise of stock options	86						86
Exercise of warrants (in shares)				4,057,307
Exercise of warrants	379						379
Conversion of convertible notes to ordinary shares (in shares)				15,896,210
Conversion of convertible notes to ordinary shares	181,404						181,404
Equity consideration (in shares)				10,000,000
Equity consideration issued	100,000						100,000
Equity consideration issued		$ 17,966	$ 50,000					$ 17,966	$ 50,000
Equity consideration issued (in shares)					1,777,031	10,562,500
Stock-based compensation	2,155						2,155
Transaction costs	(43,825)						(43,825)
Non-cash fair value of assumed liability-classified ordinary share warrants	(14,305)						(14,305)
Ordinary share issuance, net of issuance costs (in shares)				319,000
Ending balance (in shares) at Sep. 30, 2021				126,675,098
Ending balance at Sep. 30, 2021	$ 113,494						$ 499,683			$ (386,189)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net loss	$ (153,306)	$ (46,953)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation of property and equipment	3,228	2,095
Amortization of debt issuance costs	0	26
Gain on disposal of property and equipment	0	(98)
Bad debt expense	377	0
Accretion of marketable securities to redemption value	(32)	0
Stock-based compensation	5,856	5,865
Change in equity-method investment	346	941
Change in fair value of debt instrument	59,916	5,547
Change in fair value of warrant liabilities	(515)	0
Forgiveness of Paycheck Protection Program loan	(2,860)	0
Changes in operating assets and liabilities:
Accounts receivable	3,032	(1,111)
Other receivables	(6,942)	4,036
Prepaid expenses and other current assets	(7,859)	878
Other non-current assets	(1,330)	485
Trade payables	1,147	(3,915)
Accrued expenses	5,800	4,306
Other current and long-term liabilities	1,240	(840)
Net cash used in operating activities	(91,902)	(28,738)
Cash flows from investing activities:
Purchase of property and equipment	(5,698)	(1,090)
Purchase of marketable securities	(54,800)	0
Proceeds from sale of marketable securities	5,000	0
Proceeds from maturity of marketable securities	30	0
Payment for asset acquisition	(500)	0
Investment in equity method investee	0	(2,500)
Net cash used in investing activities	(55,968)	(3,590)
Cash flows from financing activities:
Proceeds from convertible loan notes	76,723	28,714
Principal payments on long-term debt	0	(1,979)
Proceeds from issuance of ordinary shares	167,966	1,961
Proceeds from Paycheck Protection Program loan	0	2,860
Proceeds from exercise of options	369	20
Proceeds from the exercise of warrants	379	7
Proceeds from issuance of warrants	263	0
Debt issuance costs incurred	(383)	0
Transaction costs	(41,484)	0
Principal payments on finance lease	0	(1,231)
Net cash provided by financing activities	203,833	30,352
Net increase (decrease) in cash and cash equivalents	55,963	(1,976)
Cash and cash equivalents:
Beginning of period	19,228	20,904
End of period	$ 75,191	$ 18,928

Description of Business and Sig

Description of Business and Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Significant Accounting Policies	Description of Business and Significant Accounting Policies Description of Business On August 11, 2021, Rockley Photonics Limited ("Legacy Rockley") completed a business combination (the "Business Combination") with SC Health Corporation, a special purpose acquisition company ("SC Health"), with Rockley Photonics Holdings Limited and its subsidiaries surviving the merger. Upon the consummation of the Business Combination, the Company became a publicly traded company listed on the New York Stock Exchange ("NYSE") under the symbol "RKLY". For additional information on the Business Combination, please refer to Note 2 , Business Combination , to these condensed consolidated financial statements. Unless the context otherwise requires, references in these notes to "Rockley", the "Company", "we", "us", or "our" and any related terms are intended to mean the post-Business Combination consolidated company, Rockley Photonics Holdings Limited, while "Legacy Rockley" and "SC Health" refers to the entities prior to the Business Combination. Rockley specializes in the research and development of integrated silicon photonics chipsets. Rockley has developed a versatile, application specific, third-generation silicon photonics platform specifically designed for the o ptical integration challenges facing numerous mega-trend markets. Rockley has partnered with multiple tier-1 customers across the markets to deliver complex optical systems required for transformational sensors, communications, and medical product realization. Basis of Presentation and Preparation The accompanying unaudited condensed consolidated financial statements have been prepared by the Company, and reflect all adjustments, consisting only of normal recurring adjustments, that are, in the opinion of management, necessary for the fair presentation of our financial position, results of operations, comprehensive income, cash flows and shareholders’ equity for the interim periods presented. The statements have been prepared in accordance with GAAP for interim financial information. Accordingly, these statements do not include all information and footnotes required by GAAP for annual consolidated financial statements, and should be read in conjunction with Legacy Rockley's audited consolidated financial statements and notes thereto as of and for the year ended December 31, 2020 in Rockley Photonics Holdings Limited 's Form S-4 Registration Statement (File No. 333-255019), which was declared effective by the SEC on July 22, 2021. The results of operations for the three and nine months ended September 30, 2021 are not necessarily indicative of the operating results to be expected for the full fiscal year or future operating periods. We accounted for the Business Combination as a forward recapitalization in accordance with GAAP (the "Forward Recapitalization"). Under this method of accounting, SC Health was treated as the acquired company and Legacy Rockley was deemed to be the accounting acquirer for financial reporting purposes. Accordingly, for accounting purposes, the Forward Recapitalization was treated as the equivalent of Legacy Rockley issuing stock for the net assets of SC Health, accompanied by a recapitalization. The net assets of SC Health are stated at historical cost, with no goodwill or other intangible assets recorded. The condensed consolidated assets, liabilities and results of operations prior to the Forward Recapitalization are those of Legacy Rockley. The condensed consolidated financial statements of the combined company post-Forward Recapitalization represents the combined results of Rockley and SC Health beginning August 11, 2021, the date the Business Combination was consummated. The shares, corresponding capital amounts and earnings per share available for shareholders of Legacy Rockley, prior to the Business Combination, converted into the right to receive 2.4835 shares (the "Exchange Ratio") of ordinary shares, par value $0.000004 (the "ordinary shares"). The recapitalization of the number of ordinary shares attributable to Legacy Rockley is reflected retroactively as shares reflecting the Exchange Ratio to the earliest period presented and is utilized for calculating earnings per share in all prior periods presented. The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Such estimates include, but are not limited to, revenue recognition, reserves and allowances; valuation of intangibles; product warranties; employee compensation and benefit accruals; stock-based compensation; loss contingencies; income taxes; fair value measurements; and warrant liabilities. Actual results could differ materially from those estimates. Management’s estimates include, as applicable, the anticipated impacts of the COVID-19 pandemic. Available-for-Sale Investments We classify our investments in debt securities as available-for-sale investments. Debt securities primarily consist of corporate bonds, commercial paper and U.S. Treasury debt securities. These investments are primarily held in the custody of a major financial institution. A specific identification method is used to determine the cost basis of debt securities sold. These investments are recorded in the consolidated balance sheets at fair value. Unrealized gains and temporary losses, net of related taxes, are included in accumulated other comprehensive income (loss) ("AOCI"). Upon realization, those amounts are reclassified from AOCI to earnings. The amortization of premiums and discounts on the investments are included in our results of operations. Realized gains and losses are calculated based on the specific identification method. We classify our investments as current or non-current based on the nature of the investment and their availability for use in current operations. Other-than-Temporary Impairments on Investments All of our available-for-sale investments are subject to periodic impairment review. When the fair value of a debt security is less than its amortized cost, it is deemed impaired, and we assess whether the impairment is other-than-temporary. An impairment is considered other-than-temporary if (i) we have the intent to sell the security, (ii) it is more likely than not that we will be required to sell the security before recovery of the entire amortized cost basis, or (iii) we do not expect to recover the entire amortized cost basis of the security. If impairment is considered other-than-temporary based on condition (i) or (ii) described above, the entire difference between the amortized cost and the fair value of the debt security is recognized in the results of operations. If an impairment is considered other-than-temporary based on condition (iii) described above, the amount representing credit losses (defined as the difference between the present value of the cash flows expected to be collected and the amortized cost basis of the debt security) is recognized in earnings, and the amount relating to all other factors is recognized in other comprehensive income (OCI). Going Concern The Company has incurred net losses since inception, has an accumulated deficit of $386.2 million as of September 30, 2021 and negative cash flow from operations of $91.9 million for the nine months ended September 30, 2021 and expects to incur losses from operations for the foreseeable future. As of September 30, 2021, the Company had cash and cash equivalents of approximately $75.2 million. The Company’s ability to meet its obligations in the ordinary course of business is dependent on its ability to obtain additional financing. As a result, there is substantial doubt about our ability to continue as a going concern. The condensed consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Our future liquidity needs, and ability to address those needs, will largely be determined by our ability to obtain additional financing on terms acceptable to us. We will continue to seek additional capital through the sale of debt or equity, or other arrangements, however, there can be no assurance that we will be able to raise additional capital when needed or under acceptable terms, if at all. The sale of additional equity may dilute existing shareholders and newly issued shares may contain senior rights and preferences compared to currently outstanding ordinary shares. Issued debt securities may contain covenants and limit our ability to pay dividends or make other distributions to shareholders. If we are unable to obtain additional financing, operations may be scaled back or discontinued. Global Pandemic The COVID-19 global pandemic has prompted extraordinary measures by governments and businesses to control the spread of COVID-19 in most or all regions throughout the world. These actions have included travel bans, quarantines, and similar mandates for individuals to substantially restrict normal activities and for businesses to curtail normal operations. The COVID – 19 pandemic has adversely impacted our operational efficiency and caused delays in operational activities. During the third quarter of 2021, we continue to take cautious steps to protect our workforce, support community efforts, and follow local government guidelines. Certain key laboratory employees and facilities have continued internal testing and laboratory work to the extent necessary to service customer commitments. The remaining non-essential workforce were recommended to continue performing their duties from home. The ongoing impact will depend on the duration of the pandemic which is being mitigated by the vaccination of the general population and gradual easing of restrictions. Recently Adopted Accounting Pronouncements In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (“Topic 820”): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement , which modifies the disclosure requirements on fair value measurements in Topic 820, based on the concepts in the Concepts Statement, including the consideration of costs and benefits. An entity is permitted to early adopt either the entire standard or only the provisions that eliminate or modify requirements. The Company adopted this guidance on January 1, 2020. The adoption of the guidance did not have a material impact on the condensed consolidated financial statements. On June 16, 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments ("Topic 326"), requiring the measurement and recognition of expected credit losses for financial assets held at amortized cost, which include our accounts receivable and contract assets. The standard also requires that the Company recognizes credit impairment losses related to our available-for-sale debt securities through an allowance for credit losses instead of a reduction in the cost basis. The Company adopted this guidance on January 1, 2021. The adoption of the guidance did not have a material impact on the condensed consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity . This ASU simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts in an entity’s own equity. The Company adopted this guidance on January 1, 2021. The adoption of the guidance did not have a material impact on the condensed consolidated financial statements. Accounting Pronouncements Issued but Not Yet Adopted In December 2019, the Financial Accounting Standard Board ("FASB") issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which affects general principles within Topic 740, and are meant to simplify and reduce the cost of accounting for income taxes. It removes certain exceptions to the general principles in Topic 740 and simplifies areas including franchise taxes that are partially based on income, transactions with a government that result in a step up in the tax basis of goodwill, the incremental approach for intraperiod tax allocation, interim period income tax accounting for year-to-date losses that exceed anticipated losses and enacted changes in tax laws in interim periods. ASU 2019-12 is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. The Company is currently evaluating the impact this guidance will have on the condensed consolidated financial statements.

Business Combination

Business Combination	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Business Combination	Business Combination On August 11, 2021 (the "Closing Date"), Legacy Rockley, SC Health, and Rockley Mergersub Limited, an exempted company incorporated in the Cayman Islands as a direct wholly owned subsidiary of the Company (“Merger Sub”), consummated the business combination contemplated by the Business Combination Agreement and Plan of Merger, dated as of March 19, 2021 (the “Business Combination Agreement”). Immediately upon the consummation of the Business Combination, Legacy Rockley became a wholly owned subsidiary of the Company and Merger Sub merged with and into SC Health, with SC Health surviving the merger and becoming a direct wholly owned subsidiary of the Company. Subsequently, SC Health's ordinary shares and warrants ceased trading on the NYSE while the Company's ordinary shares and warrants began trading on the NYSE under the symbols “RKLY” and “RKLY.WS,” respectively. Pursuant to the Business Combination Agreement, each of the following transactions occurred in the following order: (i) pursuant to a scheme of arrangement approved by the UK courts (the “Scheme”), on August 9, 2021, all of Legacy Rockley’s ordinary shares, including shares issued immediately prior to the Scheme becoming effective as a result of the conversion of then-outstanding convertible loan notes and the exercise of warrants, were transferred by Rockley shareholders in exchange for an equivalent number of shares in the Company; (ii) the holders of options over shares in Legacy Rockley rolled over their options into new options to purchase shares in the Company; (iii) warrants to purchase shares in Legacy Rockley (other than one warrant instrument that by its terms was replicated at the Company) not exercised for shares in Legacy Rockley prior to the effectiveness of the Scheme described above were cancelled, such that immediately following the Scheme, Legacy Rockley became a direct wholly-owned subsidiary of the Company; (iv) the Company subsequently completed a stock-split to prepare its share capital for Merger Sub’s merger into SC Health; (v) certain accredited investors (including entities affiliated with the SC Health Sponsor) purchased an aggregate of 15.0 million ordinary shares for a purchase price of $10.00 per share, or an aggregate purchase price of $150.0 million; (vi) on August 11, 2021, Merger Sub was merged with and into SC Health, with SC Health surviving the merger and becoming a direct wholly-owned subsidiary of the Company; and (vii) the ordinary shares and warrants in SC Health were exchanged for ordinary shares and warrants in the Company. The Business Combination was accounted for as a forward recapitalization, with no goodwill or other intangible assets recorded, in accordance with GAAP. Under this method of accounting, SC Health was treated as the acquired company and Legacy Rockley was deemed to be the accounting acquirer for financial reporting purposes. This determination was primarily based on the existing shareholders of Legacy Rockley obtaining a majority voting power in the Company, and as such, having the power to appoint a majority of the members of the Company’s board of directors (the "Board"); the operations of Legacy Rockley prior to the acquisition comprising the only ongoing operations of the combined entity based on the historical operating activity and employee base; and the senior management of Legacy Rockley comprising the majority of the senior management of the Company. Accordingly, for accounting purposes, the financial statements of the Company represent a continuation of the financial statements of Legacy Rockley with the acquisition being treated as the equivalent of Legacy Rockley issuing stock for the net assets of SC Health, accompanied by a recapitalization. As a result of the Business Combination, the Company incurred equity issuance costs and other costs considered direct and incremental to the transaction, totaling $43.8 million and consisting of legal, accounting, financial advisory and other professional fees. These amounts are reflected within additional paid-in capital in the condensed consolidated balance sheet as of September 30, 2021. Summary of Net Proceeds The following table reconciles the elements of the net proceeds from the Business Combination as of September 30, 2021 (in thousands): Recapitalization Cash inflow from SC Health's trust account, net of redemptions $ 17,966 Cash inflow from PIPE 100,000 Cash inflow from SC Health Sponsor 50,000 Less: Transaction Costs (43,825) Net cash received from the Business Combination $ 124,141 Summary of Shares Issued The total number of shares of the Company's ordinary shares issued and outstanding immediately following the consummation of the Business Combination was approximately 126.7 million, comprising (in thousands): Number of Shares Current Rockley's shareholders prior to the Business Combination 104,016 SC Health Shareholders 1,777 Sponsor Shareholders 10,563 PIPE Investors 10,000 Other Shareholders 1 319 Total number of shares 126,675 1 The Company issued 319,000 ordinary shares at a value of $10.00 per share to Cowen and Company LLC ("Cowen") and BCW Securities LLC in lieu of cash payment for a portion of the fees payable $3.2 million to Cowen as part of the transaction costs.

Segment, Geographic, and Signif

Segment, Geographic, and Significant Customer Information	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Segment, Geographic, and Significant Customer Information	Segment, Geographic, and Significant Customer Information Our operations are organized into a single operating and reportable segment for financial reporting purposes, based on how our Chief Operating Decision Maker (“CODM”) manages the business, makes operating decisions around the allocation of resources, and evaluates operating performance. Our CODM is our Chief Executive Officer, who reviews our operating results on a consolidated basis. The following table presents our revenue disaggregated by primary geographical market where revenues are attributable to the region in which the billing address of the customer is located (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) United States $ 1,537 $ 2,265 $ 5,503 $ 14,351 Rest of World $ 302 $ 2,252 $ 302 $ 4,710 Total revenue $ 1,839 $ 4,517 $ 5,805 $ 19,061 The following tables summarize our most significant customers as of September 30, 2021 and December 31, 2020 and for the three and nine months ended September 30, 2021 and 2020: Revenue Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Customer A 69 % 50 % 89 % 75 % Customer B 16 % 50 % 5 % 25 % Accounts Receivable As of September 30, 2021 December 31, 2020 (Unaudited) Customer A 63 % 33 % Customer B 20 % 67 %

Equity Method Investment

Equity Method Investment	9 Months Ended
	Sep. 30, 2021
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investment	Equity Method InvestmentAs of September 30, 2021 and December 31, 2020, we held an investment in Hengtong Rockley Technology Co., Ltd (“HRT”) and we appointed two of the HRT's five board members. HRT manufactures and sells optical fiber transceivers based on silicon photonics chipsets. HRT has share capital consisting solely of ordinary shares. We hold 24.9% of HRT’s ordinary shares, and the same proportion of its voting rights. We consider HRT to be a variable interest entity upon which the Company does exercise significant influence. However, the Company concluded it does not control the investment. Accordingly, the investment in HRT is accounted for under the equity method. We elected to use a three-month lag to record our share of HRT’s results. See Note 13 , Related Party Transactions for details on the Company’s transactions with HRT. The following table summarizes our investment in HRT for the nine months ended September 30, 2021 (in thousands): Beginning balance, January 1, 2021 $ 5,202 Investment in HRT — Remeasurement gain on HRT 374 Share of loss of HRT (720) Ending balance, September 30, 2021 $ 4,856 Our maximum exposure to loss as a result of our involvement with HRT is limited to the balance of our investment.

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Value Measurements	Financial Instruments and Fair Value Measurements The accounting guidance for fair value measurements provides a framework for measuring fair value on either a recurring or nonrecurring basis, whereby the inputs used in valuation techniques are assigned a hierarchical level. The following are the three levels of inputs to measure fair value: Level 1: Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2: Inputs that reflect quoted prices for identical assets or liabilities in less active markets; quoted prices for similar assets or liabilities in active markets; benchmark yields, reported trades, broker/dealer quotes, inputs other than quoted prices that are observable for the assets or liabilities; or inputs that are derived principally from or corroborated by observable market data by correlation or other means. Level 3: Unobservable inputs that reflect our own assumptions incorporated in valuation techniques used to measure fair value. These assumptions are required to be consistent with market participant assumptions that are reasonably available. We consider an active market to be one in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis, and consider an inactive market to be one in which there are infrequent or few transactions for the asset or liability, the prices are not current, or price quotations vary substantially either over time or among market makers. Where appropriate, our own or the counterparty’s non-performance risk is considered in measuring the fair values of liabilities and assets, respectively. Investments The following is a summary of our investments at their cost or amortized cost for the periods ended September 30, 2021 and December 31, 2020 (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Corporate bonds and commercial paper $ 25,082 $ — U.S. Treasury securities 24,668 — Total investments $ 49,750 $ — The fair value of our investments approximates their cost or amortized cost for both periods presented. The following table presents the contractual maturities of our debt investments as of September 30, 2021 (in thousands): Amortized Cost Fair Value Due in one year or less $ 29,315 $ 29,317 Due after one year through five years 20,435 20,485 $ 49,750 $ 49,802 Actual maturities may differ from the contractual maturities because borrowers may have the right to call or prepay certain obligations. Fair Value of Financial Instruments The following table summarizes our financial assets measured at fair value on a recurring basis (in thousands): September 30, 2021 Fair Value Measurements at Reporting Date Using Total Level 1 Level 2 Cash and cash equivalents $ 75,191 $ 75,191 $ — Corporate bonds and commercial paper 25,085 — 25,085 U.S. Treasury securities 24,717 24,717 — Total cash, cash equivalents and investments $ 124,993 $ 99,908 $ 25,085 December 31, 2020 Fair Value Measurements at Reporting Date Using Total Level 1 Level 2 Cash and cash equivalents $ 19,228 $ 19,228 $ — Total cash and cash equivalents $ 19,228 $ 19,228 $ — The financial liabilities subject to fair value measurement on a recurring basis, were as follows (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Financial Liabilities 3.00% – 2020 Convertible Notes $ — $ 32,106 8.00% – 2020 Convertible Notes — 14,789 2020 Term Facility Loan — 25,049 Private Placement Warrants 13,789 — Total financial liabilities $ 13,789 $ 71,944 As of September 30, 2021, there was no fair value associated with the convertible debt instruments due to the conversion of the debt securities into the Company's ordinary shares in connection with the Business Combination. The estimated fair value of the debt securities prior to their conversion into the Company's ordinary shares was $208.6 million . The estimated fair value of the convertible securities on the Closing Date was calculated as the product of (i) the number of conversion shares at the Closing Date and (ii) the marketable value per ordinary share at the Closing Date. Changes in the fair value of debt that is accounted for at fair value are presented as gains or losses in the condensed consolidated statements of operations and comprehensive loss under Change in Fair Value of Debt Instruments. 3.00% – 2020 Convertible Notes O n March 9, 2020, Legacy Rockley issued $21.3 million of the 3.00% Convertible Notes and elected the fair value option of accounting for this debt instrument (see Note 7 , Debt for details) . In connection with the closing of the Business Combination on August 11, 2021, the outstanding principal and in terest of the 3.00% Convertible Notes Due 2025 were cancelled and converted into the right to receive ordinary shares of the Company, resulting in $0.0 million outstanding balance on the 3.00% Convertible Notes at September 30, 2021. For the three and nine months ended September 30, 2021, we recorded a loss of $1.9 million and $6.0 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 3.00% Convertible Notes, as follows (in thousands): Fair value at December 31, 2020 $ 32,106 Plus: Loss from change in fair value $ 5,986 Less: Fair value adjustment extinguished upon conversion of debt $ (38,092) Fair value at September 30, 2021 $ — A binomial lattice model was used to determine the fair value of the 3.00% Convertible Notes based on assumptions as to when the notes would be converted or redeemed at each decision point. Within the lattice model, the following assumptions were made: (i) upon IPO/Sale/Merger/SPAC or maturity, the convertible notes may be converted to ordinary shares or redeemed at principal and accrued interest; and (ii) upon qualified financing event, the convertible notes will automatically convert to ordinary shares. The lattice model used the share price, conversion price, maturity date, risk-free rate, estimated stock volatility and estimated credit spread. The remeasurement of the fair value of the debt instrument was recorded as a gain or loss in the statements of operations and comprehensive loss for each reporting period. 8.00% – 2020 Convertible Notes On February 19, 2020, Legacy Rockley issued $8.0 million of 8.00% Convertible Notes and elected the fair value option of accounting for this debt instrument (see Note 7 , Debt for details). In connection with the closing of the Business Combination on August 11, 2021, the outstanding principal, interest and warrants of the 8.00% Convertible Notes were cancelled and converted into the right to receive ordinary shares of the Company, resulting in $0.0 million outstanding balance on the 8.00% Convertible Notes at September 30, 2021 . For the three and nine months ended September 30, 2021, we recorded a loss of $13.9 million and $16.1 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 8.00% Convertible Notes, as follows (in thousands): Fair value at December 31, 2020 $ 14,789 Plus: Loss from change in fair value $ 16,108 Less: Fair value adjustment extinguished upon conversion of debt $ (30,897) Fair value at September 30, 2021 $ — A binomial lattice model was used to determine the fair value of the 8.00% Convertible Notes Due 2025 based on assumptions as to when the notes would be converted or redeemed at each decision point. Within the lattice model, the following assumptions were made: (i) upon IPO/Sale/Merger/SPAC or maturity, the convertible notes may be converted to ordinary shares or put at 125% of principal and accrued interest; and (ii) upon financing event, the convertible notes may be converted to ordinary shares. The remeasurement of the fair value of the debt instrument was recorded as a gain or loss in the statements of operations and comprehensive loss for each reporting period. 2020 Term Facility Loan On September 29, 2020, Legacy Rockley issued $35.0 million of convertible notes and at inception elected the fair value option of accounting for this debt instrument ( see Note 7 , Debt for details ). In connection with the closing of the Business Combination on August 11, 2021, thirty percent (30%) of the outstanding principal and interest balance of the 2020 Term Facility Loan were cancelled and converted into the right to receive ordinary shares of the Company and seventy percent (70%) of the outstanding principal and interest balance is required to be repaid in full on or prior to August 31, 2022. At September 30, 2021, the contractual outstanding principal and interest on the 2020 Term Facility Loan was $37.3 million. For the three and nine months ended September 30, 2021, we recorded a loss of $0.2 million and $15.1 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 2020 Term Facility Loan s, as follows (in thousands): Fair value at December 31, 2020 $ 25,049 Plus: Loss from change in fair value $ 15,134 Less: Fair value adjustment extinguished upon conversion of the thirty percent (30%) balance $ (13,003) Fair value at August 11, 2021 $ 27,180 At August 11, 2021, the fair value of the 2020 Term Facility Loan was $27.2 million. The interest expense is subsequently accreted to statements of operations and comprehensive loss using the effective interest rate method over the term of the loan. A binomial lattice model was used to determine the fair value of the 2020 Term Facility Loan based on assumptions as to when the loan would be converted upon IPO/Sale/Merger/SPAC. Upon such event, the convertible notes may be paid off as following: (i) if par value exit, repayment of base multiple times principal plus unpaid interest; (ii) if greater value exit, repayment of base multiple plus add-on multiple ratio times principal plus unpaid interest. 5.00% – $50.0 Million Convertible Notes On January 11, 2021, Legacy Rockley issued $50.0 million of the 5.00% – $50.0 Million Convertible Notes (the "5.00% – $50.0 Million Convertible Notes") and at inception elected the fair value option of accounting for this debt instrument ( see Note 7 , Debt for details ). In connection with the closing of the Business Combination, the outstanding principal and interest of the 5.00% – $50.0 Million Convertible Notes were cancelled and converted into the right to receive ordinary shares of the Company, resulting in $0.0 million outstanding balance on the 5.00% – $50.0 Million Convertible Notes at September 30, 2021. For the three and nine months ended September 30, 2021 , we recorded a loss of $1.4 million and $2.3 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 5.00% – $50.0 Million Convertible Notes, as follows (in thousands): Fair value at January 11, 2021 $ 10,274 Plus: Loss from change in fair value $ 2,310 Less: Fair value adjustment extinguished upon conversion of debt $ (12,584) Fair value at September 30, 2021 $ — A binomial lattice model was used to determine the fair value of the 5.00% – $50.0 Million Convertible Notes Due 2026 based on assumptions as to when the notes would be converted or redeemed at each decision point. Within the lattice model, the following assumptions were made: (i) upon IPO/Sale/Merger/SPAC, the convertible notes may be converted to ordinary shares or put at principal and accrued interest; and (ii) upon qualified financing event or maturity, the convertible notes will automatically convert to ordinary shares at base price. The lattice model used the share price, conversion price, maturity date, risk-free rate, estimated stock volatility and estimated credit spread. The remeasurement of the fair value of the debt instrument was recorded as a gain or loss in the statements of operations and comprehensive loss for each reporting period. 5.00% – $25.0 Million Convertible Notes On December 31, 2020, Legacy Rockley issued $25.0 million of the 5.00% – $25.0 Million Convertible Notes and at inception elected the fair value option of accounting for this debt instrument ( see Note 7 , Debt for details ). In connection with the closing of the Business Combination, the outstanding principal, interest and warrants of the 5.00% – $25.0 Million Convertible Notes were cancelled and converted into the right to receive ordinary shares of the Company, resulting in $0.0 million outstanding balance on the 5.00% – $25.0 Million Convertible Notes at September 30, 2021 . For the three and nine months ended September 30, 2021, we recorded an adjustment of $(0.5) million and $5.0 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 5.00% – $25.0 Million Convertible Notes , as follows (in thousands): Fair value at December 31, 2020 $ 37,592 Plus: Loss from change in fair value $ 4,977 Less: Fair value adjustment extinguished upon conversion of debt $ (42,569) Fair value at September 30, 2021 $ — A binomial lattice model was used to determine the fair value of the 5.00% – $25.0 Million Convertible Notes Due 2025 based on assumptions as to when the notes would be converted or redeemed at each decision point. Within the lattice model, the following assumptions were made: (i) upon SPAC, the convertible notes may be converted to ordinary shares or put at principal and accrued interest; (ii) upon qualified financing event, the convertible notes may be converted to ordinary shares with discount any time after financing date; and (iii) upon maturity, the convertible notes may be converted to ordinary shares at $675.0 million divided by the number of fully diluted shares. The remeasurement of the fair value of the debt instrument was recorded as a gain or loss in the statements of operations and comprehensive loss for each reporting period. 5.00% – $30.0 Million Convertible Notes On January 11, 2021, Legacy Rockley issued $30.0 million of the 5.00% Convertible Notes and at inception elected the fair value option of accounting for this debt instrument ( see Note 7 , Debt for details ). In connection with the closing of the Business Combination, the outstanding principal and interest of the 5.00% – $30.0 Million Convertible Notes were cancelled and converted into the right to receive ordinary shares of the Company, resulting in $0.0 million outstanding balance on the 5.00% – $30.0 Million Convertible Notes at September 30, 2021. For the three and nine months ended September 30, 2021, we recorded an adjustment of $(2.6) million and $5.9 million , respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 5.00% – $30.0 Million Convertible Notes , as follows (in thousands): Fair value at January 11, 2021 $ 38,403 Plus: Loss from change in fair value $ 5,855 Less: Fair value adjustment extinguished upon conversion of debt $ (44,258) Fair value at September 30, 2021 $ — A binomial lattice model was used to determine the fair value of the 5.00% Convertible Notes Due 2026 based on assumptions as to when the notes would be converted or redeemed at each decision point. Within the lattice model, the following assumptions were made: (i) upon SPAC, the convertible notes may be converted to ordinary shares or put at principal and accrued interest; and (ii) upon qualified financing event or maturity, the convertible notes will automatically convert to ordinary shares at base price. The lattice model used the share price, conversion price, maturity date, risk-free rate, estimated stock volatility and estimated credit spread. The remeasurement of the fair value of the debt instrument was recorded as a gain or loss in the statements of operations and comprehensive loss for each reporting period. At September 30, 2021 and December 31, 2020, the carrying value of certain financial instruments, such as cash, accounts receivable, other receivable, prepaid expenses and other current assets, trade payable and other current accrued liabilities, approximate fair value due to their relatively short maturities and low market interest rates, if applicable. Private Placement Warrants The Private Placement Warrants are accounted for as liabilities in accordance with the FASB's Accounting Standards Codification ("ASC") 815-40 and are presented within the Warrants Liabilities on the condensed consolidated balance sheet. The warrant liabilities were measured at fair value at inception and are measured on a recurring basis, with changes in fair value presented within change in fair value of warrants liabilities in the condensed consolidated statement of operations and comprehensive loss. The Private Placement Warrants are measured at fair value on a recurring basis. The measurement of the warrants as of September 30, 2021 was $13.8 million. The Company has classified the Private Placement Warrants as a liability due to certain settlement terms and provisions related to certain tender offers and indexation characteristics following the Business Combination and has accounted for them as liability instruments in accordance with ASC 815, adjusting the fair value at the end of each reporting period. Additionally, the Company has determined that the Private Placement Warrants are classified within Level 3 of the fair value hierarchy as the fair value is estimated using the Modified Black Scholes Option Pricing Model. The following table presents the changes in the fair value of the Private Placement Warrants (in thousands): Initial measurement, August 11, 2021 $ 14,304 Mark-to-market adjustment $ (515) Private Placement Warrants balance, September 30, 2021 $ 13,789

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Components	Balance Sheet Components Cash and cash equivalents Cash and cash equivalents balances were concentrated by location as follows: As of September 30, 2021 December 31, 2020 (Unaudited) United Kingdom 89 % 96 % United States 11 % 3 % Other — % 1 % Other receivables (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) R&D tax credit receivable $ 23,424 $ 17,412 Grants receivable 533 — VAT receivable 1,005 607 Other receivable 4 5 Total other receivables $ 24,966 $ 18,024 Property and equipment, net (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Computer equipment $ 1,957 $ 1,218 Lab equipment 12,003 7,607 Motor vehicles 31 31 Furniture and fixtures 303 265 Leasehold improvements 909 704 Assets under construction 359 27 Total property and equipment $ 15,562 $ 9,852 Less: accumulated depreciation (8,057) (5,802) Total property and equipment, net $ 7,505 $ 4,050 Total depreciation expense for the three months ended September 30, 2021 and 2020 was $1.2 million and $0.7 million, respectively. Total depreciation expense for the nine months ended September 30, 2021 and 2020 was $3.0 million and $1.9 million, respectively. Finance lease right-of-use assets, net (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Finance lease right-of-use assets $ 2,966 $ 2,966 Less: accumulated amortization (1,113) (834) Total finance lease right-of-use assets, net $ 1,853 $ 2,132 Amortization expense for the three months ended September 30, 2021 and 2020 was $0.1 million and $0.1 million, respectively. Amortization expense for the nine months ended September 30, 2021 and 2020 was $0.3 million and $0.3 million, respectively. Intangible assets, net (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) In-process research and development $ 3,048 $ 3,048 Total intangible assets, net $ 3,048 $ 3,048 The Company reviews its intangible assets for potential impairment whenever events or circumstances indicate that the carrying value of the intangible assets may not be recoverable. No impairment charges were recorded for the three and nine months ended September 30, 2021 and 2020. Other non-current assets (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Capitalized transaction costs $ — $ 121 Security deposits $ 253 $ — Operating right of use assets $ 2,816 $ 1,486 Total other non-current assets $ 3,069 $ 1,607 Accrued expenses (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Accrued bonus $ 6,207 $ 3,349 Accrued payroll and benefits 2,908 1,524 Accrued taxes 593 332 Accrued fabrication costs 2,479 2,321 Share appreciation rights — 706 Accrued transaction costs 2,340 335 Other accrued expenses 1,594 1,828 Total accrued expenses $ 16,121 $ 10,395

Debt

Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt The following table summarizes information relating to our long-term debt, (in thousands): September 30, 2021 (Unaudited) Principal Change in Fair Value Conversion of Debt Accreted Debt Interest Net 3.00% – 2020 Convertible Notes $ 21,281 $ 16,811 (38,092) — $ — 8.00% – 2020 Convertible Notes 8,000 22,897 (30,897) — — 2020 Term Facility Loan 33,949 6,234 (13,003) 1,410 28,590 5.00% – $50.0 Million Convertible Notes 10,274 2,310 (12,584) — — 5.00% – $25.0 Million Convertible Notes 25,000 17,569 (42,569) — — 5.00% – $30.0 Million Convertible Notes 30,000 14,258 (44,258) — — Total long-term debt $ 128,504 $ 80,079 (181,403) 1,410 $ 28,590 Less: current portion of long-term debt (28,590) Long-term debt, net of current portion $ — December 31, 2020 Principal Change in Fair Value Net 3.00% – 2020 Convertible Notes $ 21,281 $ 10,825 $ 32,106 8.00% – 2020 Convertible Notes 8,000 6,789 14,789 2020 Term Facility Loan 22,500 2,549 25,049 Paycheck Protection Program 2,860 — 2,860 Total long-term debt $ 54,641 $ 20,163 $ 74,804 Less: current portion of long-term debt — Long-term debt, net of current portion $ 74,804 Future minimum payments under the Company's debt agreements as of September 30, 2021 are as follows (in thousands): 2020 Term Facility Loan 2021 (for the remaining period) $ 5,000 2022 32,303 2023 — 2024 — 2025 — Thereafter — Total future minimum payments $ 37,303 Less: current portion of debt principal (37,303) Non-current portion of debt principal $ — 3.00% – 2020 Convertible Notes The discussion on the 3.00% – 2020 Convertible Notes is fully described in Note 7 of the “Notes to Consolidated Financial Statements” included in Rockley Photonics Holdings Limited 's Registration Statement on Form S-4 (File No. 333-255019), filed with the SEC on April 2, 2021 and declared effective on July 22, 2021. Upon consummation of the Business Combination discussed in Note 2 , Business Combination , the total outstanding principal and accrued unpaid interest of $21.9 million for the 3.00% – 2020 Convertible Notes were cancelled and converted into the right to receive 3.8 million ordinary shares of the Company , with a fair value of $38.1 million , recorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. The Company recorded a $38.1 million adjustment upon extinguishment of the 3.00% – 2020 Convertible Notes. 8.00% – 2020 Convertible Notes The discussion on the 8.00% Convertible Notes is fully described in Note 7 of the “Notes to Consolidated Financial Statements” included in Rockley Photonics Holdings Limited 's Registration Statement on Form S-4 (File No. 333-255019), filed with the SEC on April 2, 2021 and declared effective on July 22, 2021. Upon consummation of the Business Combination discussed in Note 2 , Business Combination , the total outstanding principal and accrued unpaid interest of $8.9 million for the 8.00% Convertible Notes were cancelled and converted into the right to receive 1.5 million ordinary shares of the Company , with a fair value of $15.5 million, recorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. In addition, the warrants issued in conjunction with the 8.00% Convertible Note were also c ancelled and converted into the right to receive 1.5 million ordinary shares of the Company , with a fair value of $15.5 million, recorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. The Company recorded a total 30.9 million adjustment upon extinguishment of the 8.00% Convertible Notes and warrants. 2020 Term Facility Loan The discussion on the 2020 Term Facility Loan is fully described in Note 7 of the “Notes to Consolidated Financial Statements” included in Rockley Photonics Holdings Limited's Registration Statement on Form S-4 (File No. 333-255019), filed with the SEC on April 2, 2021 and declared effective on July 22, 2021. Upon consummation of the Business Combination discussed in Note 2 , Business Combination , thirty percent (30%) of the outstanding principal and interest balance of $10.2 million for the 2020 Term Facility Loan were cancelled and converted into the right to receive 1.3 million ordinary shares of the Company, with a fair value of $13.0 million, r ecorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. The Company recorded a $13.0 million adjustment upon extinguishment of debt. The seventy percent (70%) of the outstanding principal and interest balance will remain as debt and is required to be repaid in full on or prior to August 31, 2022, in the total amount of $37.3 million. At August 11, 2021, the Company recorded a fair value of $27.1 million for the seventy percent (70%) of the outstanding principal and interest balance. The Company will accrete the adjusted interest expense over the amended term of the loan using the effective interest rate method. The Company accrued unpaid interest expense of $1.4 million for the three months ended September 30, 2021. As of September 30, 2021, the total outstanding debt for the 2020 Term Facility Loan balance was $28.6 million 5.00% – $50.0 Million Convertible Notes On January 11, 2021, Legacy Rockley issued convertible loan notes for an aggregate principal amount of $50.0 million. The 5.00% – $50.0 Million Convertible Notes had an interest rate of 5.00% per annum and contained no financial covenants. The total amount borrowed was $10.3 million. The 5.00% – $50.0 Million Convertible Notes were subject to conversion as follows: (a) In the event of a qualified financing even with total proceeds raised not less than $25.0 million, the outstanding principal amount and any unpaid accrued interest automatically convert into the most senior class of share at a conversion price being lower of 15% discount to the per share subscription price of the equity shares or the price obtained by diving $1,500.0 million by fully diluted share capital of the Company at the date of conversion; (b) At an exit event, redeem the outstanding principal amount and any unpaid accrued interest on the original principal or convert the outstanding principal amount of all notes and any unpaid accrued interest into the most senior class of share of the Company at a conversion price equal to the lower of 15% discount to the price per share and the price obtained by dividing $1,500.0 million by fully diluted share capital of the Company at the date of conversion; (c) At the maturity date, convert into the most senior class of shares at a conversion price by dividing $1,500.0 million by fully diluted share capital of the Company at the date of conversion. Upon consummation of the Business Combination discussed in Note 2 , Business Combination , the total outstanding principal and accrued unpaid interest of $10.6 million for the 5.00% – $50.0 Million Convertible Notes were cancelled and converted into the right to receive 1.3 million ordinary shares of the Company , with a fair value of $12.6 million, recorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. The Company recognized a $12.6 million adjustment upon extinguishment of the 5.00% – $50.0 Million Convertible Notes. 5.00% – $25.0 Million Convertible Notes On December 31, 2020, Legacy Rockley issued convertible loan notes in an aggregate principal amount of $25.0 million. The 5.00% – $25.0 Million Convertible Notes had an interest rate of 5.0% per annum and contained no financial covenants. The 5.00% – $25.0 Million Convertible Notes were subject to conversion as follows: (a) In an equity qualified financing event with total proceeds raised not less than $25.0 million, the outstanding principal amount and any unpaid accrued interest automatically convert into the most senior class of share at a conversion price being lower of 25% discount to the per share subscription price of the equity shares or the price obtained by diving $800.0 million by fully diluted share capital of the Company at the date of conversion; (b) At an exit event, redeem the outstanding notes for an amount equal to 100% of the outstanding principal plus accrued interest or convert the outstanding principal amount into the most senior class of share of the Company, at a conversion price equal to the lower of 25% discount to the price per share and the price obtained by dividing $800.0 million by fully diluted share capital of the Company at the date of conversion; or (c) At the maturity date, convert into the most senior class of shares at a conversion price by dividing $675.0 million by the number of issued shares in the capital of the Company on a fully diluted basis or repay the amount equal to 100% of the outstanding principal amount plus any accrued interest. Upon consummation of the Business Combination discussed in Note 2 , Business Combination , the total outstanding principal and accrued unpaid interest of $25.7 million for the 5.00% – $25.0 Million Convertible Notes were cancelled and converted into the right to receive 3.6 million ordinary shares of the Company , with a fair value of $35.6 million, recorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. In addition, the warrants issued in conjunction with the 5.00% – $25.0 Million Convertible Notes were also c ancelled and converted into the right to receive 0.7 million ordinary shares of the Company , with a fair value of $7.0 million, recorded in the condensed consolidated statement of shareholders' equity (deficit)with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. The Company recorded a total $42.6 million adjustment upon extinguishment of the 5.00% – $25.0 Million Convertible Notes and warrants. 5.00% – $30.0 Million Convertible Notes On January 11, 2021, Legacy Rockley issued the 5.00% – $30.0 Million Convertible Notes. The 5.00% – $30.0 Million Convertible Notes had an interest rate of 5.0% per annum and contained no financial covenants. The 5.00% – $30.0 Million Convertible Notes were subject to conversion as follows: (a) In an equity qualified financing event with total proceeds raised not less than $25.0 million, the outstanding principal amount and any unpaid accrued interest automatically convert into the most senior class of share at a conversion price being lower of 25% discount to the per share subscription price of the equity shares or the price obtained by diving $800.0 million by fully diluted share capital of the Company at the date of conversion; (b) At an exit event, redeem the outstanding notes for an amount equal to the outstanding principal plus any unpaid accrued interest or convert the outstanding principal amount of all notes and any unpaid accrued interest into the most senior class of share of the Company, at a conversion price equal to the lower of a 25% discount to the price per share and the price obtained by dividing $800.0 million by fully diluted share capital of the Company at the date of conversion; or (c) At the maturity date, convert into the most senior class of shares at a conversion price by dividing $800.0 million by fully diluted share capital of the Company at the date of conversion. Upon consummation of the Business Combination discussed in Note 2 , Business Combination , the total outstanding principal and accrued unpaid interest of $30.8 million for the 5.00%– $30.0 Million Convertible Notes were cancelled and converted into the right to receive 4.4 million ordinary shares of the Company , with a fair value of $44.3 million, recorded in the condensed consolidated statement of shareholders' equity (deficit) with a corresponding decrease to the convertible note in the condensed consolidated balance sheet. The Company recorded a $44.3 million adjustment upon extinguishment of the 5.00%– $30.0 Million Convertible Notes. Paycheck Protection Program The discussion on paycheck protection program is fully described in Note 7 of the “Notes to Consolidated Financial Statements” included in Rockley Photonics Holdings Limited 's Registration Statement on Form S-4 (File No. 333-255019), filed with the SEC on April 2, 2021 and declared effective on July 22, 2021. During June 2021, the $2.9 million of borrowings outstanding under the Paycheck Protection Program ("PPP") Loan was forgiven in full. Forgiveness income is recorded as a component of other income, net in the condensed consolidated statements of operations and comprehensive loss.

Warrants

Warrants	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Warrants	Warrants As of September 30, 2021 , the Company had 8,625,000 Public Warrants outstanding with a balance of $28.0 million , and classified as equity, and 5,450,000 Private Placement Warrants outstanding with a balance of $13.8 million , and classified as liability. These warrants are exercisable for the Company’s ordinary shares. Warrants may only be exercised for a whole number of shares at an exercise price of $11.50. These warrants expire five years from the closing of the Forward Recapitalization. The ordinary shares underlying the warrants were registered on Rockley Photonics Holdings Limited 's Registration Statement on Form S-4 (File No. 333-255019), filed with the SEC on April 2, 2021 and declared effective on July 22, 2021. The Company is obligated to issue ordinary shares upon exercise of a warrant. Redemption of warrants when the ordinary share price equals or exceeds $18.00. Once the warrants become exercisable, the Company may redeem the warrants in whole and not in part, at a price of $0.01 per warrant, upon not less than 30 days’ prior written notice of redemption to each warrant holder and if, and only if, the closing price of the Company’s ordinary shares equals or exceeds $18.00 per share (as adjusted for share sub-divisions, share capitalizations, reorganizations, recapitalizations and the like) for any 20 trading days within a 30-trading day period ending on the third trading day prior to the date on which the notice of redemption is given to the warrant holders. The Company may redeem the warrants in whole and not in part no earlier than 90 days after they are first exercisable and prior to their expiration at a price equal to a number of the Company's ordinary shares based on the redemption date and the “fair market value” of the ordinary shares, upon not less than 30 days' prior written notice of redemption each warrant holder, and if, and only if, the closing price of the ordinary shares equals or exceeds $10.00 per share (as adjusted for share sub-divisions, share dividends, reorganizations, reclassifications, recapitalizations and the like) on the trading day before the Company sends the notice of redemption to the warrant holders. The Private Placement Warrants were accounted for as liabilities in accordance with ASC 815-40, Derivatives and Hedging-Contracts in Entity’s Own Equity , and are presented within warrant liabilities on our balance sheet. The warrant liabilities assumed from SC Health, and on a recurring basis, changes in fair value will be presented in the consolidated statement of operations at each reporting period. The Private Placement Warrants are considered to be a Level 3 liability, see Note 5 – Fair Value Measurements for description of the valuation methodology of the Private Placement Warrants.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense was $0.6 million and $0.2 million for the three months ended September 30, 2021 and 2020, respectively. Income tax expense was $0.8 million and $0.4 million for the nine months ended September 30, 2021 and 2020, respectively. The effective income tax rate was less than 1.0% in the three and nine months ended September 30, 2021 and 2020. Our effective tax rate differs from the U.K. statutory rate primarily due to a substantially full valuation allowance against our net deferre d tax assets where it is more likely than not that some or all of the deferred tax assets will not be realized. The income tax expense is primarily related to corporate income taxes in the United States, which operates on a cost–plus arrangements and minimum filing fees in the foreign jurisdictions where we have operations.

Shareholders_ Equity (Deficit)

Shareholders’ Equity (Deficit)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Shareholders’ Equity (Deficit)	Shareholders’ Equity (Deficit) The Company is authorized to issue 12,417,500,000 ordinary shares with par value of $0.000004 per share. Each holder of the Company's ordinary shares is entitled to one vote per share. As of September 30, 2021, there were 126,675,098 of the Company's ordinary shares issued and outstanding. Holders of the Company's ordinary shares do not have cumulative voting rights. Additionally, the Company has 14,074,986 warrants outstanding as of September 30, 2021. See Note 8 , Warrants for additional information. Each holder of the Company's ordinary shares is entitled to the payment of dividends and other distributions as may be declared by the Board from time to time out of the Company’s assets or funds legally available for dividends or other distributions. The Company has not declared or paid any dividends with respect to its ordinary shares for the periods presented. If the Company is involved in voluntary or involuntary liquidation, dissolution or winding up of the Company’s affairs, or a similar event, each holder of the Company ordinary shares will participate pro rata in all assets remaining after payment of liabilities, subject to prior distribution rights of the Company preferred shares, if any, then outstanding.

Net Loss per Share

Net Loss per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss per Share The following is a calculation of basic and diluted net loss per share (in thousands, except for share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Basic and diluted: Net loss $ (57,972) $ (20,524) $ (153,306) $ (46,953) Weighted average ordinary shares 107,633,037 83,509,920 92,008,435 83,392,042 Basic and diluted net loss per share $ (0.54) $ (0.25) $ (1.67) $ (0.56) Basic net loss per share is calculated by dividing net loss for the period by the weighted average number of the ordinary shares outstanding plus outstanding warrants with a $0.01 exercise price.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Company has established a number of share-based incentive plans for current employees, directors and others, which include Share Appreciation Rights ("SARs"), 2013 Share Option Plan, 2021 Share Option Plan and Warrants. Share Appreciation Rights As of September 30, 2021, there were no SARs outstanding. In connection with the Business Combination on August 11, 2021, the liability associated with outstanding SARs was settled with a cash payment of $0.7 million. 2013 Share Option Plan The holders of Legacy Rockley options under the 2013 Share Option Plan (the "2013 Plan") continue to hold such options and such options remain subject to the same vesting, exercise and other terms and conditions. In connection with the Business Combination, the holders of Legacy Rockley options may exercise their options to purchase a number of ordinary shares equal to the number of shares of Legacy Rockley ordinary shares subject to such Legacy Rockley options multiplied by the Exchange Ratio of 2.4835 (rounded down to the nearest whole share) at an exercise price per share divided by the Exchange Ratio (rounded to the nearest whole cent). The information presented herein is as if the exchange of stock options occurred as of the earliest period presented. As of September 30, 2021 , there were 0 shares available for grant. Any new grants will become available for issuance under the 2021 Stock Incentive Plan (the "2021 Plan"). The following table summarizes the stock option activity related to the 2013 Plan : Number of Average Remaining Aggregate Intrinsic 1 (In thousands) Options outstanding at December 31, 2020 17,898,619 $ 1.99 6.75 44,515 Granted — $ — Exercised (465,853) $ 0.79 Forfeited (890,369) $ 4.07 Expired (35,742) $ 2.92 Options outstanding at September 30, 2021 16,506,655 $ 1.91 5.80 $ 92,787 Options exercisable—September 30, 2021 12,925,646 $ 1.50 5.05 $ 77,978 2021 Stock Incentive Plan On March 31, 2021, the Board approved the 2021 Plan. The purpose of the 2021 Plan is to attract, retain, incentivize and reward top talent through stock ownership, to improve operating and financial performance and strengthen the mutuality of interest between eligible service providers and shareholders. As of September 30, 2021 , there were 15,369,185 shares authorized for issuance under the Plan, of which 14,355,705 shares were available for grant. The following table summarizes the stock option activity related to the 2021 Plan: Number of Average Remaining Intrinsic (In thousands) Options outstanding at December 31, 2020 — $ — 0.00 — Options granted 1,013,480 $ 15.84 Options exercised — $ — Options forfeited — $ — Options expired — $ — Options outstanding at September 30, 2021 1,013,480 $ 15.84 9.86 $ — Options exercisable—September 30, 2021 20,384 $ 15.84 9.86 $ — Stock-based compensation expense The following table summarizes our stock-based compensation expense for all equity arrangements and is included in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 ( Unaudited) ( Unaudited) Cost of revenue $ 346 $ 467 $ 977 $ 1,808 Research and development 1,340 891 3,559 2,971 Selling, general and administrative 469 319 1,320 1,086 Total stock-based compensation expense $ 2,155 $ 1,677 $ 5,856 $ 5,865 As of September 30, 2021, total unrecognized compensation expense related to unvested options granted to employees under the Company’s stock option plans was $17.6 million, which is expected to be recognized over a weighted average peri od of 1.3 years. Performance Options For the three months ended September 30, 2021 and 2020, we recognized a total expense of $0.1 million and $0.02 million in relation to the performance-based options. For the nine months ended September 30, 2021 and 2020, we recognized a total expense of $0.3 million and $0.1 million. As of September 30, 2021 and December 31, 2020, there were approximately $0.9 million and $1.2 million of unrecognized stock-based compensation expense related to the performance-based options. During the nine months ended September 30, 2021, no additional performance-based options were granted. Warrants

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company formed HRT, a joint venture with Hengtong Optic-Electric Co., Ltd. in 2017, which was recognized by the Company as an equity method investment. The total sales made to HRT for the three months ended September 30, 2021 and 2020 were $0.3 million and $2.3 million, respectively. The total sales made to HRT for the nine months ended September 30, 2021 and 2020 were $0.3 million and $4.7 million, respectively . As of September 30, 2021 and December 31, 2020, the balance owed by the joint venture amounted to $0.3 million and $3.3 million, respectively, and is included in accounts receivable in the accompanying balance sheets. As of September 30, 2021 and December 31, 2020, the balance owed to the joint venture was $0 and $0.2 million, respectively, and included in trade payables

Leases

Leases	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Leases	Leases The weighted average remaining lease term was 1 year for operating leases as of September 30, 2021. The weighted average discount rate was 6% for operating leases as of September 30, 2021. Finance lease costs were immaterial for the three and nine months ended September 30, 2021 and 2020. The components of operating lease cost for the three and nine months ended September 30, 2021 and 2020, were as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Operating Lease Cost: Fixed lease cost $ 268 213 $ 773 638 Variable lease cost 81 (3) 200 118 Total operating lease cost $ 349 $ 210 $ 973 $ 756 The supplemental cash flow information related to our operating leases is as follows (in thousands): Nine Months Ended September 30, 2021 2020 Supplemental Cash Flow Information: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 706 $ 685 Operating cash flows for finance leases $ — $ 12 Financing cash flows for finance leases $ — $ 933 Right-of-use assets obtained in exchange of lease obligations: Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,981 $ — There are no finance lease liabilities as of September 30, 2021. Maturities of operating lease liabilities as of September 30, 2021, are as follows (in thousands): Operating Leases 2021 (for the remaining period) $ 230 2022 1,165 2023 931 2024 437 2025 327 Thereafter 394 Total lease obligation $ 3,484 Less: Imputed interest (363) Total lease liabilities $ 3,121 Less: Current lease liabilities (923) Total non-current lease liabilities $ 2,198
Leases	Leases The weighted average remaining lease term was 1 year for operating leases as of September 30, 2021. The weighted average discount rate was 6% for operating leases as of September 30, 2021. Finance lease costs were immaterial for the three and nine months ended September 30, 2021 and 2020. The components of operating lease cost for the three and nine months ended September 30, 2021 and 2020, were as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Operating Lease Cost: Fixed lease cost $ 268 213 $ 773 638 Variable lease cost 81 (3) 200 118 Total operating lease cost $ 349 $ 210 $ 973 $ 756 The supplemental cash flow information related to our operating leases is as follows (in thousands): Nine Months Ended September 30, 2021 2020 Supplemental Cash Flow Information: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 706 $ 685 Operating cash flows for finance leases $ — $ 12 Financing cash flows for finance leases $ — $ 933 Right-of-use assets obtained in exchange of lease obligations: Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,981 $ — There are no finance lease liabilities as of September 30, 2021. Maturities of operating lease liabilities as of September 30, 2021, are as follows (in thousands): Operating Leases 2021 (for the remaining period) $ 230 2022 1,165 2023 931 2024 437 2025 327 Thereafter 394 Total lease obligation $ 3,484 Less: Imputed interest (363) Total lease liabilities $ 3,121 Less: Current lease liabilities (923) Total non-current lease liabilities $ 2,198

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Contingencies From time to time, we are a party to various lawsuits, claims and other legal proceedings that arise in the ordinary course of business. We apply accounting for contingencies to determine when and how much to accrue for and disclose related to legal and other contingencies. Accordingly, we disclose contingencies deemed to be reasonably possible and accrue loss contingencies when, in consultation with legal advisors, it is concluded that a loss is probable and reasonably estimable. Although the ultimate aggregate amount of monetary liability or financial impact with respect to these matters is subject to many uncertainties and is therefore not predictable with assurance, management believes that as of September 30, 2021 there is no litigation pending that could have, individually and in the aggregate, a material adverse effect on our financial position, results of operations or cash flows. Financial Commitments In the ordinary course of business, we make commitments to third-party suppliers for various research and development activities. As of September 30, 2021 and December 31, 2020, we had $8.9 million and $3.0 million, respectively, in contractual obligations for which we have not yet received the services.

Defined Contribution Plan

Defined Contribution Plan	9 Months Ended
	Sep. 30, 2021
Retirement Benefits [Abstract]
Defined Contribution Plan	Defined Contribution PlanWe have defined contribution plans, under which we contribute based on a percentage of the employees’ elected contributions. We will have no legal or constructive obligation to pay further amounts. Obligations for contributions to defined contribution plans are recognized within selling, general and administrative expenses and research and development in the condensed consolidated statements of operations and comprehensive loss. Defined contributions were $0.2 million and $0.1 million for the three months ended September 30, 2021 and 2020, respectively. Defined contributions were $0.6 million and $0.4 million for the nine months ended September 30, 2021 and 2020, respectively.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	9 Months Ended
	Sep. 30, 2021
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information Non-cash operating, investing, and financing activities, and supplemental cash flow information are as follows (in thousands): Nine Months Ended September 30, 2021 2020 (Unaudited) Supplemental Cash Flow Information: Interest paid $ 465 $ 49 Income tax paid $ 300 $ 147 Non-cash Operating Activities: Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,981 $ — $ 1,981 $ — Non-cash Investing Activities: Unpaid property and equipment received $ 707 $ 222 $ 707 $ 222 Non-cash Financing Activities: Conversion of convertible debt and accrued interest to ordinary shares $ 181,404 $ — Conversion of Legacy Rockley ordinary shares to Rockley ordinary shares 206,888 — Private Placement Warrants 14,304 — Public Warrants 28,031 — Issuance of ordinary shares in lieu of cash payment of transaction costs 3,190 — Unpaid deferred transaction costs 2,263 — Forgiveness of Paycheck Protection Program loan 2,860 — $ 438,940 $ —

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Subsequent events have been evaluated through the date that these financial statements were issued. In October 2021, the Company filed a registration statement on Form S-8 under the Securities Act of 1933 (the "S-8 Registration Statement"). The S-8 Registration Statement registered a total of 33,410,136 ordinary shares, which includes all shares issued under the 2021 Plan and the 2021 Employee Stock Purchase Plan (the “ESPP”). Once these shares are registered, they can be sold in the public market upon issuance, subject to applicable restrictions. On October 19, 2021, the Board unanimously approved to enter into and consummate a "Term Sheet" with Lincoln Park Capital Fund, LLC, an Illinois limited liability company ("LPCF"). The Term Sheet is a private placement with registration rights, providing LPCF the ability to purchase up to $50.0 million of the Company's ordinary shares. The term of the Term Sheet is 24 months. Following the execution of the term sheet, the Company is to pay LPCF $0.04 million to cover associated expenses relating to, amongst other things, preparation of future securities agreements relating to the Term Sheet. Any proceeds from the sale of shares, pursuant to the aforementioned term sheet, are to go towards the Company to be used for working capital.

Description of Business and S_2

Description of Business and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Preparation	Basis of Presentation and Preparation The accompanying unaudited condensed consolidated financial statements have been prepared by the Company, and reflect all adjustments, consisting only of normal recurring adjustments, that are, in the opinion of management, necessary for the fair presentation of our financial position, results of operations, comprehensive income, cash flows and shareholders’ equity for the interim periods presented. The statements have been prepared in accordance with GAAP for interim financial information. Accordingly, these statements do not include all information and footnotes required by GAAP for annual consolidated financial statements, and should be read in conjunction with Legacy Rockley's audited consolidated financial statements and notes thereto as of and for the year ended December 31, 2020 in Rockley Photonics Holdings Limited 's Form S-4 Registration Statement (File No. 333-255019), which was declared effective by the SEC on July 22, 2021. The results of operations for the three and nine months ended September 30, 2021 are not necessarily indicative of the operating results to be expected for the full fiscal year or future operating periods. We accounted for the Business Combination as a forward recapitalization in accordance with GAAP (the "Forward Recapitalization"). Under this method of accounting, SC Health was treated as the acquired company and Legacy Rockley was deemed to be the accounting acquirer for financial reporting purposes. Accordingly, for accounting purposes, the Forward Recapitalization was treated as the equivalent of Legacy Rockley issuing stock for the net assets of SC Health, accompanied by a recapitalization. The net assets of SC Health are stated at historical cost, with no goodwill or other intangible assets recorded. The condensed consolidated assets, liabilities and results of operations prior to the Forward Recapitalization are those of Legacy Rockley. The condensed consolidated financial statements of the combined company post-Forward Recapitalization represents the combined results of Rockley and SC Health beginning August 11, 2021, the date the Business Combination was consummated. The shares, corresponding capital amounts and earnings per share available for shareholders of Legacy Rockley, prior to the Business Combination, converted into the right to receive 2.4835 shares (the "Exchange Ratio") of ordinary shares, par value $0.000004 (the "ordinary shares"). The recapitalization of the number of ordinary shares attributable to Legacy Rockley is reflected retroactively as shares reflecting the Exchange Ratio to the earliest period presented and is utilized for calculating earnings per share in all prior periods presented. The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Such estimates include, but are not limited to, revenue recognition, reserves and allowances; valuation of intangibles; product warranties; employee compensation and benefit accruals; stock-based compensation; loss contingencies; income taxes; fair value measurements; and warrant liabilities. Actual results could differ materially from those estimates. Management’s estimates include, as applicable, the anticipated impacts of the COVID-19 pandemic.
Available-for-Sale Investments and Other-than-Temporary Impairments on Investments	Available-for-Sale Investments We classify our investments in debt securities as available-for-sale investments. Debt securities primarily consist of corporate bonds, commercial paper and U.S. Treasury debt securities. These investments are primarily held in the custody of a major financial institution. A specific identification method is used to determine the cost basis of debt securities sold. These investments are recorded in the consolidated balance sheets at fair value. Unrealized gains and temporary losses, net of related taxes, are included in accumulated other comprehensive income (loss) ("AOCI"). Upon realization, those amounts are reclassified from AOCI to earnings. The amortization of premiums and discounts on the investments are included in our results of operations. Realized gains and losses are calculated based on the specific identification method. We classify our investments as current or non-current based on the nature of the investment and their availability for use in current operations. Other-than-Temporary Impairments on Investments All of our available-for-sale investments are subject to periodic impairment review. When the fair value of a debt security is less than its amortized cost, it is deemed impaired, and we assess whether the impairment is other-than-temporary. An impairment is considered other-than-temporary if (i) we have the intent to sell the security, (ii) it is more likely than not that we will be required to sell the security before recovery of the entire amortized cost basis, or (iii) we do not expect to recover the entire amortized cost basis of the security. If impairment is considered other-than-temporary based on condition (i) or (ii) described above, the entire difference between the amortized cost and the fair value of the debt security is recognized in the results of operations. If an impairment is considered other-than-temporary based on condition (iii) described above, the amount representing credit losses (defined as the difference between the present value of the cash flows expected to be collected and the amortized cost basis of the debt security) is recognized in earnings, and the amount relating to all other factors is recognized in other comprehensive income (OCI).
Going Concern	Going Concern The Company has incurred net losses since inception, has an accumulated deficit of $386.2 million as of September 30, 2021 and negative cash flow from operations of $91.9 million for the nine months ended September 30, 2021 and expects to incur losses from operations for the foreseeable future. As of September 30, 2021, the Company had cash and cash equivalents of approximately $75.2 million. The Company’s ability to meet its obligations in the ordinary course of business is dependent on its ability to obtain additional financing. As a result, there is substantial doubt about our ability to continue as a going concern. The condensed consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Our future liquidity needs, and ability to address those needs, will largely be determined by our ability to obtain additional financing on terms acceptable to us. We will continue to seek additional capital through the sale of debt or equity, or other arrangements, however, there can be no assurance that we will be able to raise additional capital when needed or under acceptable terms, if at all. The sale of additional equity may dilute existing shareholders and newly issued shares may contain senior rights and preferences compared to currently outstanding ordinary shares. Issued debt securities may contain covenants and limit our ability to pay dividends or make other distributions to shareholders. If we are unable to obtain additional financing, operations may be scaled back or discontinued.
Global Pandemic	Global Pandemic The COVID-19 global pandemic has prompted extraordinary measures by governments and businesses to control the spread of COVID-19 in most or all regions throughout the world. These actions have included travel bans, quarantines, and similar mandates for individuals to substantially restrict normal activities and for businesses to curtail normal operations. The COVID –
Recently Adopted Accounting Pronouncements and Accounting Pronouncements Issued but Not Yet Adopted	Recently Adopted Accounting Pronouncements In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (“Topic 820”): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement , which modifies the disclosure requirements on fair value measurements in Topic 820, based on the concepts in the Concepts Statement, including the consideration of costs and benefits. An entity is permitted to early adopt either the entire standard or only the provisions that eliminate or modify requirements. The Company adopted this guidance on January 1, 2020. The adoption of the guidance did not have a material impact on the condensed consolidated financial statements. On June 16, 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments ("Topic 326"), requiring the measurement and recognition of expected credit losses for financial assets held at amortized cost, which include our accounts receivable and contract assets. The standard also requires that the Company recognizes credit impairment losses related to our available-for-sale debt securities through an allowance for credit losses instead of a reduction in the cost basis. The Company adopted this guidance on January 1, 2021. The adoption of the guidance did not have a material impact on the condensed consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity . This ASU simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts in an entity’s own equity. The Company adopted this guidance on January 1, 2021. The adoption of the guidance did not have a material impact on the condensed consolidated financial statements. Accounting Pronouncements Issued but Not Yet Adopted In December 2019, the Financial Accounting Standard Board ("FASB") issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which affects general principles within Topic 740, and are meant to simplify and reduce the cost of accounting for income taxes. It removes certain exceptions to the general principles in Topic 740 and simplifies areas including franchise taxes that are partially based on income, transactions with a government that result in a step up in the tax basis of goodwill, the incremental approach for intraperiod tax allocation, interim period income tax accounting for year-to-date losses that exceed anticipated losses and enacted changes in tax laws in interim periods. ASU 2019-12 is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. The Company is currently evaluating the impact this guidance will have on the condensed consolidated financial statements.

Business Combination (Tables)

Business Combination (Tables)	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Schedule of Proceeds from Business Combination	The following table reconciles the elements of the net proceeds from the Business Combination as of September 30, 2021 (in thousands): Recapitalization Cash inflow from SC Health's trust account, net of redemptions $ 17,966 Cash inflow from PIPE 100,000 Cash inflow from SC Health Sponsor 50,000 Less: Transaction Costs (43,825) Net cash received from the Business Combination $ 124,141 Summary of Shares Issued The total number of shares of the Company's ordinary shares issued and outstanding immediately following the consummation of the Business Combination was approximately 126.7 million, comprising (in thousands): Number of Shares Current Rockley's shareholders prior to the Business Combination 104,016 SC Health Shareholders 1,777 Sponsor Shareholders 10,563 PIPE Investors 10,000 Other Shareholders 1 319 Total number of shares 126,675 1 The Company issued 319,000 ordinary shares at a value of $10.00 per share to Cowen and Company LLC ("Cowen") and BCW Securities LLC in lieu of cash payment for a portion of the fees payable $3.2 million to Cowen as part of the transaction costs.

Segment, Geographic, and Sign_2

Segment, Geographic, and Significant Customer Information (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table presents our revenue disaggregated by primary geographical market where revenues are attributable to the region in which the billing address of the customer is located (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) United States $ 1,537 $ 2,265 $ 5,503 $ 14,351 Rest of World $ 302 $ 2,252 $ 302 $ 4,710 Total revenue $ 1,839 $ 4,517 $ 5,805 $ 19,061
Schedules of Concentration of Risk, by Customer	The following tables summarize our most significant customers as of September 30, 2021 and December 31, 2020 and for the three and nine months ended September 30, 2021 and 2020: Revenue Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Customer A 69 % 50 % 89 % 75 % Customer B 16 % 50 % 5 % 25 % Accounts Receivable As of September 30, 2021 December 31, 2020 (Unaudited) Customer A 63 % 33 % Customer B 20 % 67 %

Equity Method Investment (Table

Equity Method Investment (Tables)	9 Months Ended
	Sep. 30, 2021
Equity Method Investments and Joint Ventures [Abstract]
Summary of Investments	The following table summarizes our investment in HRT for the nine months ended September 30, 2021 (in thousands): Beginning balance, January 1, 2021 $ 5,202 Investment in HRT — Remeasurement gain on HRT 374 Share of loss of HRT (720) Ending balance, September 30, 2021 $ 4,856

Financial Instruments and Fai_2

Financial Instruments and Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Summary of Debt Securities	The following is a summary of our investments at their cost or amortized cost for the periods ended September 30, 2021 and December 31, 2020 (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Corporate bonds and commercial paper $ 25,082 $ — U.S. Treasury securities 24,668 — Total investments $ 49,750 $ — The following table presents the contractual maturities of our debt investments as of September 30, 2021 (in thousands): Amortized Cost Fair Value Due in one year or less $ 29,315 $ 29,317 Due after one year through five years 20,435 20,485 $ 49,750 $ 49,802
Fair Value, by Balance Sheet Grouping	The following table summarizes our financial assets measured at fair value on a recurring basis (in thousands): September 30, 2021 Fair Value Measurements at Reporting Date Using Total Level 1 Level 2 Cash and cash equivalents $ 75,191 $ 75,191 $ — Corporate bonds and commercial paper 25,085 — 25,085 U.S. Treasury securities 24,717 24,717 — Total cash, cash equivalents and investments $ 124,993 $ 99,908 $ 25,085 December 31, 2020 Fair Value Measurements at Reporting Date Using Total Level 1 Level 2 Cash and cash equivalents $ 19,228 $ 19,228 $ — Total cash and cash equivalents $ 19,228 $ 19,228 $ — The financial liabilities subject to fair value measurement on a recurring basis, were as follows (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Financial Liabilities 3.00% – 2020 Convertible Notes $ — $ 32,106 8.00% – 2020 Convertible Notes — 14,789 2020 Term Facility Loan — 25,049 Private Placement Warrants 13,789 — Total financial liabilities $ 13,789 $ 71,944
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis	For the three and nine months ended September 30, 2021, we recorded a loss of $1.9 million and $6.0 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 3.00% Convertible Notes, as follows (in thousands): Fair value at December 31, 2020 $ 32,106 Plus: Loss from change in fair value $ 5,986 Less: Fair value adjustment extinguished upon conversion of debt $ (38,092) Fair value at September 30, 2021 $ — For the three and nine months ended September 30, 2021, we recorded a loss of $13.9 million and $16.1 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 8.00% Convertible Notes, as follows (in thousands): Fair value at December 31, 2020 $ 14,789 Plus: Loss from change in fair value $ 16,108 Less: Fair value adjustment extinguished upon conversion of debt $ (30,897) Fair value at September 30, 2021 $ — For the three and nine months ended September 30, 2021, we recorded a loss of $0.2 million and $15.1 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 2020 Term Facility Loan s, as follows (in thousands): Fair value at December 31, 2020 $ 25,049 Plus: Loss from change in fair value $ 15,134 Less: Fair value adjustment extinguished upon conversion of the thirty percent (30%) balance $ (13,003) Fair value at August 11, 2021 $ 27,180 For the three and nine months ended September 30, 2021 , we recorded a loss of $1.4 million and $2.3 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 5.00% – $50.0 Million Convertible Notes, as follows (in thousands): Fair value at January 11, 2021 $ 10,274 Plus: Loss from change in fair value $ 2,310 Less: Fair value adjustment extinguished upon conversion of debt $ (12,584) Fair value at September 30, 2021 $ — For the three and nine months ended September 30, 2021, we recorded an adjustment of $(0.5) million and $5.0 million, respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 5.00% – $25.0 Million Convertible Notes , as follows (in thousands): Fair value at December 31, 2020 $ 37,592 Plus: Loss from change in fair value $ 4,977 Less: Fair value adjustment extinguished upon conversion of debt $ (42,569) Fair value at September 30, 2021 $ — For the three and nine months ended September 30, 2021, we recorded an adjustment of $(2.6) million and $5.9 million , respectively from a change in fair value of debt in connection with the subsequent fair value remeasurement of the 5.00% – $30.0 Million Convertible Notes , as follows (in thousands): Fair value at January 11, 2021 $ 38,403 Plus: Loss from change in fair value $ 5,855 Less: Fair value adjustment extinguished upon conversion of debt $ (44,258) Fair value at September 30, 2021 $ — The following table presents the changes in the fair value of the Private Placement Warrants (in thousands): Initial measurement, August 11, 2021 $ 14,304 Mark-to-market adjustment $ (515) Private Placement Warrants balance, September 30, 2021 $ 13,789

Balance Sheet Components (Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Cash and Cash Equivalents	Cash and cash equivalents Cash and cash equivalents balances were concentrated by location as follows: As of September 30, 2021 December 31, 2020 (Unaudited) United Kingdom 89 % 96 % United States 11 % 3 % Other — % 1 %
Schedule of Other Receivables	Other receivables (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) R&D tax credit receivable $ 23,424 $ 17,412 Grants receivable 533 — VAT receivable 1,005 607 Other receivable 4 5 Total other receivables $ 24,966 $ 18,024
Schedule of Property, Plant and Equipment	Property and equipment, net (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Computer equipment $ 1,957 $ 1,218 Lab equipment 12,003 7,607 Motor vehicles 31 31 Furniture and fixtures 303 265 Leasehold improvements 909 704 Assets under construction 359 27 Total property and equipment $ 15,562 $ 9,852 Less: accumulated depreciation (8,057) (5,802) Total property and equipment, net $ 7,505 $ 4,050
Finance Lease, Right-Of-Use Assets	Finance lease right-of-use assets, net (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Finance lease right-of-use assets $ 2,966 $ 2,966 Less: accumulated amortization (1,113) (834) Total finance lease right-of-use assets, net $ 1,853 $ 2,132
Schedule of Intangible Assets, Net	Intangible assets, net (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) In-process research and development $ 3,048 $ 3,048 Total intangible assets, net $ 3,048 $ 3,048
Schedule of Other Non-current Assets	Other non-current assets (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Capitalized transaction costs $ — $ 121 Security deposits $ 253 $ — Operating right of use assets $ 2,816 $ 1,486 Total other non-current assets $ 3,069 $ 1,607
Schedule of Accrued Expenses	Accrued expenses (in thousands): As of September 30, 2021 December 31, 2020 (Unaudited) Accrued bonus $ 6,207 $ 3,349 Accrued payroll and benefits 2,908 1,524 Accrued taxes 593 332 Accrued fabrication costs 2,479 2,321 Share appreciation rights — 706 Accrued transaction costs 2,340 335 Other accrued expenses 1,594 1,828 Total accrued expenses $ 16,121 $ 10,395

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Long-term Debt	The following table summarizes information relating to our long-term debt, (in thousands): September 30, 2021 (Unaudited) Principal Change in Fair Value Conversion of Debt Accreted Debt Interest Net 3.00% – 2020 Convertible Notes $ 21,281 $ 16,811 (38,092) — $ — 8.00% – 2020 Convertible Notes 8,000 22,897 (30,897) — — 2020 Term Facility Loan 33,949 6,234 (13,003) 1,410 28,590 5.00% – $50.0 Million Convertible Notes 10,274 2,310 (12,584) — — 5.00% – $25.0 Million Convertible Notes 25,000 17,569 (42,569) — — 5.00% – $30.0 Million Convertible Notes 30,000 14,258 (44,258) — — Total long-term debt $ 128,504 $ 80,079 (181,403) 1,410 $ 28,590 Less: current portion of long-term debt (28,590) Long-term debt, net of current portion $ — December 31, 2020 Principal Change in Fair Value Net 3.00% – 2020 Convertible Notes $ 21,281 $ 10,825 $ 32,106 8.00% – 2020 Convertible Notes 8,000 6,789 14,789 2020 Term Facility Loan 22,500 2,549 25,049 Paycheck Protection Program 2,860 — 2,860 Total long-term debt $ 54,641 $ 20,163 $ 74,804 Less: current portion of long-term debt — Long-term debt, net of current portion $ 74,804
Schedule of Future Maturities of Debt Agreements	Future minimum payments under the Company's debt agreements as of September 30, 2021 are as follows (in thousands): 2020 Term Facility Loan 2021 (for the remaining period) $ 5,000 2022 32,303 2023 — 2024 — 2025 — Thereafter — Total future minimum payments $ 37,303 Less: current portion of debt principal (37,303) Non-current portion of debt principal $ —

Net Loss per Share (Tables)

Net Loss per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Net Loss Per Share, Basic and Diluted	The following is a calculation of basic and diluted net loss per share (in thousands, except for share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Basic and diluted: Net loss $ (57,972) $ (20,524) $ (153,306) $ (46,953) Weighted average ordinary shares 107,633,037 83,509,920 92,008,435 83,392,042 Basic and diluted net loss per share $ (0.54) $ (0.25) $ (1.67) $ (0.56)

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Summary of Stock Option Activity	The following table summarizes the stock option activity related to the 2013 Plan : Number of Average Remaining Aggregate Intrinsic 1 (In thousands) Options outstanding at December 31, 2020 17,898,619 $ 1.99 6.75 44,515 Granted — $ — Exercised (465,853) $ 0.79 Forfeited (890,369) $ 4.07 Expired (35,742) $ 2.92 Options outstanding at September 30, 2021 16,506,655 $ 1.91 5.80 $ 92,787 Options exercisable—September 30, 2021 12,925,646 $ 1.50 5.05 $ 77,978 Number of Average Remaining Intrinsic (In thousands) Options outstanding at December 31, 2020 — $ — 0.00 — Options granted 1,013,480 $ 15.84 Options exercised — $ — Options forfeited — $ — Options expired — $ — Options outstanding at September 30, 2021 1,013,480 $ 15.84 9.86 $ — Options exercisable—September 30, 2021 20,384 $ 15.84 9.86 $ —
Schedule of Stock-Based Compensation Expense	The following table summarizes our stock-based compensation expense for all equity arrangements and is included in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 ( Unaudited) ( Unaudited) Cost of revenue $ 346 $ 467 $ 977 $ 1,808 Research and development 1,340 891 3,559 2,971 Selling, general and administrative 469 319 1,320 1,086 Total stock-based compensation expense $ 2,155 $ 1,677 $ 5,856 $ 5,865

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Summary of Operating Lease Information	The components of operating lease cost for the three and nine months ended September 30, 2021 and 2020, were as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (Unaudited) (Unaudited) Operating Lease Cost: Fixed lease cost $ 268 213 $ 773 638 Variable lease cost 81 (3) 200 118 Total operating lease cost $ 349 $ 210 $ 973 $ 756 The supplemental cash flow information related to our operating leases is as follows (in thousands): Nine Months Ended September 30, 2021 2020 Supplemental Cash Flow Information: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows for operating leases $ 706 $ 685 Operating cash flows for finance leases $ — $ 12 Financing cash flows for finance leases $ — $ 933 Right-of-use assets obtained in exchange of lease obligations: Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,981 $ —
Schedule of Maturity of Operating Lease Liabilities	Maturities of operating lease liabilities as of September 30, 2021, are as follows (in thousands): Operating Leases 2021 (for the remaining period) $ 230 2022 1,165 2023 931 2024 437 2025 327 Thereafter 394 Total lease obligation $ 3,484 Less: Imputed interest (363) Total lease liabilities $ 3,121 Less: Current lease liabilities (923) Total non-current lease liabilities $ 2,198

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	9 Months Ended
	Sep. 30, 2021
Supplemental Cash Flow Elements [Abstract]
Schedule of Supplemental Cash Flow Information	Non-cash operating, investing, and financing activities, and supplemental cash flow information are as follows (in thousands): Nine Months Ended September 30, 2021 2020 (Unaudited) Supplemental Cash Flow Information: Interest paid $ 465 $ 49 Income tax paid $ 300 $ 147 Non-cash Operating Activities: Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,981 $ — $ 1,981 $ — Non-cash Investing Activities: Unpaid property and equipment received $ 707 $ 222 $ 707 $ 222 Non-cash Financing Activities: Conversion of convertible debt and accrued interest to ordinary shares $ 181,404 $ — Conversion of Legacy Rockley ordinary shares to Rockley ordinary shares 206,888 — Private Placement Warrants 14,304 — Public Warrants 28,031 — Issuance of ordinary shares in lieu of cash payment of transaction costs 3,190 — Unpaid deferred transaction costs 2,263 — Forgiveness of Paycheck Protection Program loan 2,860 — $ 438,940 $ —

Description of Business and S_3

Description of Business and Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Thousands	Aug. 11, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Entity shares issued per acquiree share, ratio	248.35%
Ordinary shares, par value (in dollars per share)		$ 0.000004
Accumulated deficit		$ (386,189)		$ (232,883)
Net cash used in operating activities		(91,902)	$ (28,738)
Cash and cash equivalents		$ 75,191		$ 19,228

Business Combination - Narrativ

Business Combination - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Aug. 11, 2021	Sep. 30, 2021	Dec. 31, 2020
Business Combination and Asset Acquisition [Abstract]
Sale of stock, number of shares issued in transaction (in shares)	15
Shares issued, price per share (in dollars per share)	$ 10
Sale of stock, consideration received on transaction	$ 150,000
Capitalized transaction costs	$ 43,800	$ 0	$ 121

Business Combination - Summary

Business Combination - Summary of Proceeds from Business Combination (Details) $ in Thousands	Aug. 11, 2021USD ($)
Business Acquisition [Line Items]
Cash inflow from PIPE	$ 100,000
Capitalized transaction costs	(43,825)
Net cash received from the Business Combination	124,141
SC Health
Business Acquisition [Line Items]
Cash inflow from recapitalization	17,966
SC Health Sponsor
Business Acquisition [Line Items]
Cash inflow from recapitalization	$ 50,000

Business Combination - Summar_2

Business Combination - Summary of Shares Issued (Details) - USD ($) $ / shares in Units, $ in Millions	Aug. 11, 2021	Sep. 30, 2021	Aug. 10, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Ordinary shares outstanding (in shares)	126,675,000	126,675,098		83,539,382
PIPE Investors (in shares)	10,000,000
Shares issued, price per share (in dollars per share)	$ 10
Legacy Rockley
Business Acquisition [Line Items]
Ordinary shares outstanding (in shares)			104,016,000
SC Health
Business Acquisition [Line Items]
Equity consideration issued (in shares)	1,777,000
SC Health Sponsor
Business Acquisition [Line Items]
Equity consideration issued (in shares)	10,563,000
Cowen and BCW Securities
Business Acquisition [Line Items]
Equity consideration issued (in shares)	319,000
Business combination, transaction costs payable to acquiree		$ 3.2

Segment, Geographic, and Sign_3

Segment, Geographic, and Significant Customer Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Concentration Risk [Line Items]
Revenue	$ 1,839	$ 4,517	$ 5,805	$ 19,061
Revenue | Customer Concentration Risk | Customer A
Concentration Risk [Line Items]
Concentration risk	69.00%	50.00%	89.00%	75.00%
Revenue | Customer Concentration Risk | Customer B
Concentration Risk [Line Items]
Concentration risk	16.00%	50.00%	5.00%	25.00%
Accounts Receivable | Customer Concentration Risk | Customer A
Concentration Risk [Line Items]
Concentration risk			63.00%		33.00%
Accounts Receivable | Customer Concentration Risk | Customer B
Concentration Risk [Line Items]
Concentration risk			20.00%		67.00%
United States
Concentration Risk [Line Items]
Revenue	$ 1,537	$ 2,265	$ 5,503	$ 14,351
Rest of World
Concentration Risk [Line Items]
Revenue	$ 302	$ 2,252	$ 302	$ 4,710

Equity Method Investment (Detai

Equity Method Investment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Equity Method Investment
Beginning balance, January 1, 2021			$ 5,202
Investment in equity method investee			0	$ 2,500
Share of loss of HRT	$ 40	$ (689)	(720)	$ (941)
Ending balance, September 30, 2021	$ 4,856		$ 4,856
HRT | Variable Interest Entity
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	24.90%		24.90%
Equity Method Investment
Beginning balance, January 1, 2021			$ 5,202
Investment in equity method investee			0
Remeasurement gain on HRT			374
Share of loss of HRT			(720)
Ending balance, September 30, 2021	$ 4,856		$ 4,856

Financial Instruments and Fai_3

Financial Instruments and Fair Value Measurements - Financial Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, amortized cost	$ 49,750	$ 0
Corporate bonds and commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, amortized cost	25,082	0
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, amortized cost	$ 24,668	$ 0

Financial Instruments and Fai_4

Financial Instruments and Fair Value Measurements - Summary of Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amortized Cost
Due in one year or less	$ 29,315
Due after one year through five years	20,435
Debt securities, amortized cost	49,750	$ 0
Fair Value
Due in one year or less	29,317
Due after one year through five years	20,485
Debt securities, fair value	$ 49,802

Financial Instruments and Fai_5

Financial Instruments and Fair Value Measurements - Financial Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Aug. 10, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 75,191		$ 19,228
Debt securities, fair value	49,802
Total cash, cash equivalents and investments	124,993		19,228
2020 Term Facility Loan	0		25,049
Private Placement Warrants	13,789		0
Total financial liabilities	$ 13,789		71,944
Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes		$ 208,600
Debt instrument, stated percentage	5.00%
3.00% – 2020 Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes	$ 0		$ 32,106
3.00% – 2020 Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage	0.03%		0.03%
8.00% – 2020 Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes	$ 0		$ 14,789
8.00% – 2020 Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage	0.08%		0.08%
Corporate bonds and commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, fair value	$ 25,085
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, fair value	24,717
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	75,191		$ 19,228
Total cash, cash equivalents and investments	99,908		19,228
Level 1 | Corporate bonds and commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, fair value	0
Level 1 | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, fair value	24,717
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0		0
Total cash, cash equivalents and investments	25,085		$ 0
Level 2 | Corporate bonds and commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, fair value	25,085
Level 2 | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, fair value	$ 0

Financial Instruments and Fai_6

Financial Instruments and Fair Value Measurements - Narrative (Details) - USD ($)	Aug. 11, 2021	Sep. 30, 2021	Sep. 30, 2020	Aug. 11, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Aug. 12, 2021	Aug. 10, 2021	Jan. 11, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt		$ 28,590,000			$ 28,590,000	$ 28,590,000					$ 74,804,000
Gain (loss) on debt instrument		$ (14,255,000)	$ (3,325,000)			$ (59,916,000)	$ (5,547,000)
Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes									$ 208,600,000
Debt instrument, stated percentage		5.00%			5.00%	5.00%
2020 Term Facility Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes	$ 27,200,000			$ 27,200,000
Debt instrument, face amount		$ 35,000,000			$ 35,000,000	$ 35,000,000
Long-term debt		28,590,000			28,590,000	28,590,000					25,049,000
Gain (loss) on debt instrument		(200,000)		(15,134,000)		(15,100,000)
Debt conversion, percent converted	30.00%
Debt conversion, percent not converted	70.00%
Outstanding principal and interest	$ 10,200,000			10,200,000				$ 37,300,000
Private Placement Warrants, fair value	27,180,000			27,180,000							25,049,000
3.00% – 2020 Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes		$ 0			$ 0	$ 0					$ 32,106,000
3.00% – 2020 Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage		0.03%			0.03%	0.03%					0.03%
Debt instrument, face amount		$ 21,300,000			$ 21,300,000	$ 21,300,000
Long-term debt		0			0	0					$ 32,106,000
Gain (loss) on debt instrument		(1,900,000)				(5,986,000)
Outstanding principal and interest	21,900,000			21,900,000
Private Placement Warrants, fair value		0			0	0					32,106,000
8.00% – 2020 Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible notes		$ 0			$ 0	$ 0					$ 14,789,000
8.00% – 2020 Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage		0.08%			0.08%	0.08%					0.08%
Debt instrument, face amount		$ 8,000,000			$ 8,000,000	$ 8,000,000
Long-term debt		0			0	$ 0					$ 14,789,000
Debt instrument, redemption price, percentage						125.00%
Gain (loss) on debt instrument		(13,900,000)				$ (16,108,000)
Outstanding principal and interest	8,900,000			8,900,000
Private Placement Warrants, fair value		$ 0			$ 0	$ 0					14,789,000
5.00% – $50.0 Million Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage		5.00%			5.00%	5.00%
Debt instrument, face amount		$ 50,000,000			$ 50,000,000	$ 50,000,000
Long-term debt		0			0	0
Gain (loss) on debt instrument		(1,400,000)			(2,310,000)	(2,300,000)
Outstanding principal and interest	10,600,000			10,600,000
Debt instrument, convertible, denominator used to calculate conversion price at maturity date, amount		1,500,000,000			1,500,000,000	1,500,000,000
Private Placement Warrants, fair value		$ 0			$ 0	$ 0				$ 10,274,000
5.00% – $25.0 Million Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage		5.00%			5.00%	5.00%
Debt instrument, face amount		$ 25,000,000			$ 25,000,000	$ 25,000,000
Long-term debt		0			0	0
Gain (loss) on debt instrument		500,000				(4,977,000)
Outstanding principal and interest	25,700,000			25,700,000
Debt instrument, convertible, denominator used to calculate conversion price at maturity date, amount		675,000,000			675,000,000	675,000,000
Private Placement Warrants, fair value		$ 0			$ 0	$ 0					$ 37,592,000
5.00% – $30.0 Million Convertible Notes | Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, stated percentage		5.00%			5.00%	5.00%
Debt instrument, face amount		$ 30,000,000			$ 30,000,000	$ 30,000,000
Long-term debt		0			0	0
Gain (loss) on debt instrument		2,600,000			(5,855,000)	(5,900,000)
Outstanding principal and interest	$ 30,800,000			$ 30,800,000
Debt instrument, convertible, denominator used to calculate conversion price at maturity date, amount		800,000,000			800,000,000	800,000,000
Private Placement Warrants, fair value		$ 0			$ 0	$ 0				$ 38,403,000

Financial Instruments and Fai_7

Financial Instruments and Fair Value Measurements - Fair Value Rollforward (Details) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended		7 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Aug. 11, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Plus: Loss from change in fair value		$ 14,255	$ 3,325			$ 59,916	$ 5,547
Warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 14,304
Plus: Loss from change in fair value	(515)
Ending balance	13,789	13,789		$ 14,304	$ 13,789	13,789
2020 Term Facility Loan
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	27,180			25,049		25,049
Plus: Loss from change in fair value		200		15,134		15,100
Less: Fair value adjustment extinguished upon conversion of debt				(13,003)
Ending balance				27,180
3.00% – 2020 Convertible Notes | Convertible Notes
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance				32,106		32,106
Plus: Loss from change in fair value		1,900				5,986
Less: Fair value adjustment extinguished upon conversion of debt						(38,092)
Ending balance	0	0			0	0
8.00% – 2020 Convertible Notes | Convertible Notes
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance				14,789		14,789
Plus: Loss from change in fair value		13,900				16,108
Less: Fair value adjustment extinguished upon conversion of debt						(30,897)
Ending balance	0	0			0	0
5.00% – $50.0 Million Convertible Notes | Convertible Notes
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance					10,274
Plus: Loss from change in fair value		1,400			2,310	2,300
Less: Fair value adjustment extinguished upon conversion of debt					(12,584)
Ending balance	0	0			0	0
5.00% – $25.0 Million Convertible Notes | Convertible Notes
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance				$ 37,592		37,592
Plus: Loss from change in fair value		(500)				4,977
Less: Fair value adjustment extinguished upon conversion of debt						(42,569)
Ending balance	0	0			0	0
5.00% – $30.0 Million Convertible Notes | Convertible Notes
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance					38,403
Plus: Loss from change in fair value		(2,600)			5,855	5,900
Less: Fair value adjustment extinguished upon conversion of debt					(44,258)
Ending balance	$ 0	$ 0			$ 0	$ 0

Balance Sheet Components - Cash

Balance Sheet Components - Cash and Cash Equivalents (Details) - Cash and Cash Equivalents - Geographic Concentration Risk	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
United Kingdom
Cash and Cash Equivalents [Line Items]
Concentration risk	89.00%	96.00%
United States
Cash and Cash Equivalents [Line Items]
Concentration risk	11.00%	3.00%
Other
Cash and Cash Equivalents [Line Items]
Concentration risk	0.00%	1.00%

Balance Sheet Components - Othe

Balance Sheet Components - Other Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
R&D tax credit receivable	$ 23,424	$ 17,412
Grants receivable	533	0
VAT receivable	1,005	607
Other receivables	4	5
Total other receivables	$ 24,966	$ 18,024

Balance Sheet Components - Long

Balance Sheet Components - Long Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 15,562		$ 15,562		$ 9,852
Less: accumulated depreciation	(8,057)		(8,057)		(5,802)
Total property and equipment, net	7,505		7,505		4,050
Depreciation	1,200	$ 700	3,000	$ 1,900
Finance lease right-of-use assets	2,966		2,966		2,966
Less: accumulated amortization	(1,113)		(1,113)		(834)
Total finance lease right-of-use assets, net	$ 1,853		$ 1,853		$ 2,132
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, equipment, net		Property, equipment, net		Property, equipment, net
Amortization	$ 100	$ 100	$ 300	$ 300
Computer equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	1,957		1,957		$ 1,218
Lab equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	12,003		12,003		7,607
Motor vehicles
Property, Plant and Equipment [Line Items]
Total property and equipment	31		31		31
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment	303		303		265
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	909		909		704
Assets under construction
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 359		$ 359		$ 27

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Indefinite-lived Intangible Assets [Line Items]
Intangible assets, net	$ 3,048	$ 3,048
In-process research and development
Indefinite-lived Intangible Assets [Line Items]
Intangible assets, net	$ 3,048	$ 3,048

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Other Non-current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Aug. 11, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Capitalized transaction costs	$ 0	$ 43,800	$ 121
Security deposits	$ 253		$ 0
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other non-current assets		Other non-current assets
Operating right of use assets	$ 2,816		$ 1,486
Other non-current assets	$ 3,069		$ 1,607

Balance Sheet Components - Sc_3

Balance Sheet Components - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued bonus	$ 6,207	$ 3,349
Accrued payroll and benefits	2,908	1,524
Accrued taxes	593	332
Accrued fabrication costs	2,479	2,321
Share appreciation rights	0	706
Accrued transaction costs	2,340	335
Other accrued expenses	1,594	1,828
Accrued expenses	$ 16,121	$ 10,395

Debt - Summary of Long Term Deb

Debt - Summary of Long Term Debt (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal	$ 128,504,000	$ 54,641,000
Change in Fair Value	80,079,000	20,163,000
Conversion of Debt	(181,403,000)
Accreted Debt Interest	1,410,000
Total long-term debt	28,590,000	74,804,000
Less: current portion of long-term debt	(28,590,000)	0
Long-term debt, net of current portion	$ 0	$ 74,804,000
Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage	5.00%
Convertible Notes | 3.00% – 2020 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage	0.03%	0.03%
Debt instrument, face amount	$ 21,300,000
Principal	21,281,000	$ 21,281,000
Change in Fair Value	16,811,000	10,825,000
Conversion of Debt	(38,092,000)
Accreted Debt Interest	0
Total long-term debt	$ 0	$ 32,106,000
Convertible Notes | 8.00% – 2020 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage	0.08%	0.08%
Debt instrument, face amount	$ 8,000,000
Principal	8,000,000	$ 8,000,000
Change in Fair Value	22,897,000	6,789,000
Conversion of Debt	(30,897,000)
Accreted Debt Interest	0
Total long-term debt	$ 0	14,789,000
Convertible Notes | 5.00% – $50.0 Million Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage	5.00%
Debt instrument, face amount	$ 50,000,000
Principal	10,274,000
Change in Fair Value	2,310,000
Conversion of Debt	(12,584,000)
Accreted Debt Interest	0
Total long-term debt	$ 0
Convertible Notes | 5.00% – $25.0 Million Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage	5.00%
Debt instrument, face amount	$ 25,000,000
Principal	25,000,000
Change in Fair Value	17,569,000
Conversion of Debt	(42,569,000)
Accreted Debt Interest	0
Total long-term debt	$ 0
Convertible Notes | 5.00% – $30.0 Million Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage	5.00%
Debt instrument, face amount	$ 30,000,000
Principal	30,000,000
Change in Fair Value	14,258,000
Conversion of Debt	(44,258,000)
Accreted Debt Interest	0
Total long-term debt	0
2020 Term Facility Loan
Debt Instrument [Line Items]
Debt instrument, face amount	35,000,000
Principal	33,949,000	22,500,000
Change in Fair Value	6,234,000	2,549,000
Conversion of Debt	(13,003,000)
Accreted Debt Interest	1,410,000
Total long-term debt	$ 28,590,000	25,049,000
Paycheck Protection Program
Debt Instrument [Line Items]
Principal		2,860,000
Change in Fair Value		0
Total long-term debt		$ 2,860,000

Debt - Schedule of Future Minim

Debt - Schedule of Future Minimum Payments (Details) - Convertible Notes $ in Thousands	Sep. 30, 2021USD ($)
Debt Instrument [Line Items]
2021 (for the remaining period)	$ 5,000
2022	32,303
2023	0
2024	0
2025	0
Thereafter	0
Total future minimum payments	37,303
Less: current portion of long-term debt	(37,303)
Non-current portion of debt principal	$ 0

Debt - Narrative (Details)

Debt - Narrative (Details) - USD ($) shares in Millions	Aug. 11, 2021	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Aug. 12, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt conversion, amount					$ 181,404,000	$ 0
Conversion of debt					181,403,000
Long-term debt			$ 28,590,000		28,590,000			$ 74,804,000
Forgiveness of Paycheck Protection Program loan		$ 2,900,000	$ 0	$ 0	$ 2,860,000	$ 0
Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage			5.00%		5.00%
Convertible Notes | 3.00% – 2020 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage			0.03%		0.03%			0.03%
Outstanding principal and interest	$ 21,900,000
Debt conversion, shares issued (in shares)	3.8
Debt conversion, amount	$ 38,100,000
Conversion of debt					$ 38,092,000
Long-term debt			$ 0		0			$ 32,106,000
Debt instrument, face amount			$ 21,300,000		$ 21,300,000
Convertible Notes | 8.00% – 2020 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage			0.08%		0.08%			0.08%
Outstanding principal and interest	$ 8,900,000
Debt conversion, shares issued (in shares)	1.5
Debt conversion, amount	$ 15,500,000
Conversion of debt					$ 30,897,000
Long-term debt			$ 0		0			$ 14,789,000
Debt instrument, face amount			$ 8,000,000		$ 8,000,000
Convertible Notes | 5.00% – $50.0 Million Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage			5.00%		5.00%
Outstanding principal and interest	$ 10,600,000
Debt conversion, shares issued (in shares)	1.3
Debt conversion, amount	$ 12,600,000
Conversion of debt					$ 12,584,000
Long-term debt			$ 0		0
Debt instrument, face amount			50,000,000		50,000,000
Debt conversion, principal amount	10,300,000
Proceeds from equity triggering debt conversion, minimum, amount			$ 25,000,000		$ 25,000,000
Debt instrument, convertible, conversion price, discount			15.00%		15.00%
Debt instrument, convertible, denominator used to calculate conversion price, amount			$ 1,500,000,000		$ 1,500,000,000
Debt instrument, convertible, denominator used to calculate conversion price at maturity date, amount			$ 1,500,000,000		$ 1,500,000,000
Convertible Notes | 5.00% – $25.0 Million Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage			5.00%		5.00%
Outstanding principal and interest	$ 25,700,000
Debt conversion, shares issued (in shares)	3.6
Debt conversion, amount	$ 35,600,000
Conversion of debt					$ 42,569,000
Long-term debt			$ 0		0
Debt instrument, face amount			25,000,000		25,000,000
Proceeds from equity triggering debt conversion, minimum, amount			$ 25,000,000		$ 25,000,000
Debt instrument, convertible, conversion price, discount			25.00%		25.00%
Debt instrument, convertible, denominator used to calculate conversion price, amount			$ 800,000,000		$ 800,000,000
Debt instrument, convertible, denominator used to calculate conversion price at maturity date, amount			$ 675,000,000		$ 675,000,000
Debt instrument, conversion price					100.00%
Convertible Notes | 5.00% – $25.0 Million Convertible Notes | Warrants
Debt Instrument [Line Items]
Debt conversion, shares issued (in shares)	0.7
Debt conversion, amount	$ 7,000,000
Convertible Notes | 5.00% – $30.0 Million Convertible Notes
Debt Instrument [Line Items]
Debt instrument, stated percentage			5.00%		5.00%
Outstanding principal and interest	$ 30,800,000
Debt conversion, shares issued (in shares)	4.4
Debt conversion, amount	$ 44,300,000
Conversion of debt					$ 44,258,000
Long-term debt			$ 0		0
Debt instrument, face amount			30,000,000		30,000,000
Proceeds from equity triggering debt conversion, minimum, amount			$ 25,000,000		$ 25,000,000
Debt instrument, convertible, conversion price, discount			25.00%		25.00%
Debt instrument, convertible, denominator used to calculate conversion price, amount			$ 800,000,000		$ 800,000,000
Debt instrument, convertible, denominator used to calculate conversion price at maturity date, amount			800,000,000		800,000,000
2020 Term Facility Loan
Debt Instrument [Line Items]
Outstanding principal and interest	$ 10,200,000						$ 37,300,000
Debt conversion, shares issued (in shares)	1.3
Debt conversion, amount	$ 13,000,000
Conversion of debt					13,003,000
Debt conversion, percent converted	30.00%
Debt conversion, percent not converted	70.00%
Fair value of outstanding principal and interest	$ 27,100,000
Interest paid			1,400,000
Long-term debt			28,590,000		28,590,000			$ 25,049,000
Debt instrument, face amount			$ 35,000,000		$ 35,000,000

Warrants (Details)

Warrants (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)tradingDay$ / sharesshares	Dec. 31, 2020USD ($)
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares) | shares	14,074,986
Warrant liabilities | $	$ 13,789	$ 0
Warrants outstanding, exercise price (in dollars per share)	$ 11.50
Minimum days notice before redemption | tradingDay	30
Redemption period, threshold trading days | tradingDay	20
Redemption period, threshold consecutive trading days | tradingDay	30
Redemption, minimum days after exercisable date before redemption	90 days
Warrant Redemption Scenario One
Class of Warrant or Right [Line Items]
Warrants outstanding, exercise price (in dollars per share)	$ 0.01
Common stock, redemption price (in dollars per share)	18
Warrant Redemption Scenario Two
Class of Warrant or Right [Line Items]
Common stock, redemption price (in dollars per share)	$ 10
Public Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares) | shares	8,625,000,000
Warrant liabilities | $	$ 28,000
Private Placement Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares) | shares	5,450,000,000,000
Warrant liabilities | $	$ 13,800

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Provision for income tax	$ 598	$ 154	$ 808	$ 374
Effective income tax rate, percent (less than)	1.00%	1.00%	1.00%	1.00%

Shareholders_ Equity (Deficit)

Shareholders’ Equity (Deficit) (Details) - $ / shares	Sep. 30, 2021	Aug. 11, 2021	Dec. 31, 2020
Equity [Abstract]
Ordinary shares authorized (in shares)	12,417,500,000		139,033,366
Ordinary shares, par value (in dollars per share)	$ 0.000004
Ordinary shares issued (in shares)	126,675,098		83,539,382
Ordinary shares outstanding (in shares)	126,675,098	126,675,000	83,539,382
Warrants outstanding (in shares)	14,074,986

Net Loss per Share - Net Loss A

Net Loss per Share - Net Loss Available to Ordinary Shareholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Class of Warrant or Right [Line Items]
Net loss, basic	$ (57,972)	$ (20,524)	$ (153,306)	$ (46,953)
Net loss, diluted	$ (57,972)	$ (20,524)	$ (153,306)	$ (46,953)
Basic (in shares)	107,633,037	83,509,920	92,008,435	83,392,042
Diluted (in shares)	107,633,037	83,509,920	92,008,435	83,392,042
Basic (in dollars per share)	$ (0.54)	$ (0.25)	$ (1.67)	$ (0.56)
Diluted (in dollars per share)	(0.54)	$ (0.25)	(1.67)	$ (0.56)
Warrants outstanding, exercise price (in dollars per share)	11.50		$ 11.50
Antidilutive securities (in shares)			13,100,000	12,900,000
Warrant Redemption Scenario One
Class of Warrant or Right [Line Items]
Warrants outstanding, exercise price (in dollars per share)	$ 0.01		$ 0.01

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	Aug. 11, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Entity shares issued per acquiree share, ratio	248.35%
Unrecognized compensation expense, options		$ 17,600		$ 17,600
Total stock-based compensation expense		2,155	$ 1,677	5,856	$ 5,865
Unrecognized compensation expense		$ 900		900		$ 1,200
Debt conversion, amount				$ 181,404	0
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Entity shares issued per acquiree share, ratio	248.35%
Convertible Notes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants exercised (in shares)	1,800,000
Warrants exercised, fair value	$ 18,100
Share Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)		0		0
Payment to settle awards	$ 700
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, period for recognition				1 year 3 months 18 days
Options | 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)		0		0
Options | 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)		14,355,705,000,000		14,355,705,000,000
Number of shares authorized (in shares)		15,369,185,000,000		15,369,185,000,000
Performance Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		$ 100	$ 20	$ 300	$ 100

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares
2013 Plan
Number of Options Outstanding
Beginning balance (in shares) | shares	17,898,619
Granted (in shares) | shares	0
Exercised (in shares) | shares	(465,853)
Forfeited (in shares) | shares	(890,369)
Expired (in shares) | shares	(35,742)
Ending balance (in shares) | shares	16,506,655	17,898,619
Options exercisable (in shares) | shares	12,925,646
Average Exercise Price Per Share
Beginning balance (in dollars per share) | $ / shares	$ 1.99
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	0.79
Forfeited (in dollars per share) | $ / shares	4.07
Expired (in dollars per share) | $ / shares	2.92
Ending balance (in dollars per share) | $ / shares	1.91	$ 1.99
Options exercisable (in dollars per share) | $ / shares	$ 1.50
Options outstanding, remaining contractual life	5 years 9 months 18 days	6 years 9 months
Options exercisable, remaining contractual life	5 years 18 days
Options outstanding, intrinsic value | $	$ 92,787	$ 44,515
Options exercisable, intrinsic value | $	$ 77,978
2021 Plan
Number of Options Outstanding
Beginning balance (in shares) | shares	0
Granted (in shares) | shares	1,013,480
Exercised (in shares) | shares	0
Forfeited (in shares) | shares	0
Expired (in shares) | shares	0
Ending balance (in shares) | shares	1,013,480	0
Options exercisable (in shares) | shares	20,384
Average Exercise Price Per Share
Beginning balance (in dollars per share) | $ / shares	$ 0
Granted (in dollars per share) | $ / shares	15.84
Exercised (in dollars per share) | $ / shares	0
Forfeited (in dollars per share) | $ / shares	0
Expired (in dollars per share) | $ / shares	0
Ending balance (in dollars per share) | $ / shares	15.84	$ 0
Options exercisable (in dollars per share) | $ / shares	$ 15.84
Options outstanding, remaining contractual life	9 years 10 months 9 days	0 years
Options exercisable, remaining contractual life	9 years 10 months 9 days
Options outstanding, intrinsic value | $	$ 0	$ 0
Options exercisable, intrinsic value | $	$ 0

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 2,155	$ 1,677	$ 5,856	$ 5,865
Per share value of ordinary shares (in dollars per share)	$ 7.19		$ 7.19
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 346	467	$ 977	1,808
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,340	891	3,559	2,971
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 469	$ 319	$ 1,320	$ 1,086

Related Party Transactions (Det

Related Party Transactions (Details) - Variable Interest Entity - HRT - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Sales to related parties	$ 300,000	$ 2,300,000	$ 300,000	$ 4,700,000
Accounts receivable, related parties, current	300,000		300,000		$ 3,300,000
Accounts payable, related parties, current	$ 0		$ 0		$ 200,000

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Operating lease, weighted average remaining lease term	1 year		1 year
Operating lease, weighted average discount rate	6.00%		6.00%
Operating Lease Cost:
Fixed lease cost	$ 268	$ 213	$ 773	$ 638
Variable lease cost	81	(3)	200	118
Total operating lease cost	$ 349	$ 210	973	756
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows for operating leases			706	685
Operating cash flows for finance leases			0	12
Financing cash flows for finance leases			0	933
Right-of-use assets obtained in exchange of lease obligations:
Right-of-use assets obtained in exchange for new operating lease liabilities			$ 1,981	$ 0

Leases - Schedule of Maturities

Leases - Schedule of Maturities of Operating Leases (Details) $ in Thousands	Sep. 30, 2021USD ($)
Leases [Abstract]
2021 (for the remaining period)	$ 230
2022	1,165
2023	931
2024	437
2025	327
Thereafter	394
Total lease obligation	3,484
Less: Imputed interest	(363)
Total lease liabilities	$ 3,121
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities
Less: Current lease liabilities	$ (923)
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term liabilities
Total non-current lease liabilities	$ 2,198

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Contractual obligations	$ 8.9	$ 3

Defined Contribution Plan (Deta

Defined Contribution Plan (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Retirement Benefits [Abstract]
Defined contribution plan, employer contributions	$ 0.2	$ 0.1	$ 0.6	$ 0.4

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Supplemental Cash Flow Information:
Interest paid				$ 465	$ 49
Income tax paid				300	147
Non-cash Operating Activities:
Right-of-use assets obtained in exchange for new operating lease liabilities				1,981	0
Total non-cash operating activities				1,981	0
Non-cash Investing Activities:
Unpaid property and equipment received				707	222
Total non-cash investing activities				707	222
Non-cash Financing Activities:
Debt conversion, amount				181,404	0
Conversion of Legacy Rockley ordinary shares to Rockley ordinary shares				206,888	0
Private Placement Warrants				14,304	0
Public Warrants				28,031	0
Issuance of ordinary shares in lieu of cash payment of transaction costs				3,190	0
Unpaid deferred transaction costs				2,263	0
Forgiveness of Paycheck Protection Program loan	$ 2,900	$ 0	$ 0	2,860	0
Total non-cash financing activities				$ 438,940	$ 0

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Thousands	Oct. 19, 2021	Aug. 11, 2021	Oct. 31, 2021
Subsequent Event [Line Items]
Sale of stock, number of shares issued in transaction (in shares)		15,000,000
Sale of stock, consideration received on transaction		$ 150,000
Subsequent Event | Employee Stock
Subsequent Event [Line Items]
Sale of stock, number of shares issued in transaction (in shares)			33,410,136
Subsequent Event | Private Placement
Subsequent Event [Line Items]
Sale of stock, consideration received on transaction	$ 50,000
Sale of stock, term	24 months
Stock issuance costs	$ 40