Cardlytics (CDLX) 10-Q 10 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 30, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Cardlytics, Inc.
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Entity Central Index Key	1,666,071
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding (in shares)		20,264,127

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash and cash equivalents	$ 89,785	$ 21,262
Accounts receivable, net	39,907	48,348
Other receivables	2,748	2,898
Prepaid expenses and other assets	3,658	2,121
Total current assets	136,098	74,629
PROPERTY AND EQUIPMENT, net	7,363	7,319
INTANGIBLE ASSETS, net	359	528
CAPITALIZED SOFTWARE DEVELOPMENT COSTS, net	880	433
DEFERRED FI IMPLEMENTATION COSTS, net	12,119	13,625
OTHER LONG-TERM ASSETS	988	4,224
Total assets	157,807	100,758
CURRENT LIABILITIES:
Accounts payable	1,783	1,554
Accrued liabilities:
Accrued compensation	3,263	4,638
Accrued expenses	3,918	4,615
FI Share liability	21,376	23,914
Consumer Incentive liability	6,949	7,242
Deferred billings	189	132
Short-term warrant liability	17,666	0
Short-term debt:
Line of credit	25,634	0
Capital leases	23	44
Total current liabilities	80,801	42,139
LONG-TERM LIABILITIES:
Deferred liabilities	3,554	3,670
Long-term warrant liability	0	10,230
Long-term debt, net of current portion:
Line of credit	0	25,081
Term loan	32,842	31,830
Capital leases	52	57
Total long-term liabilities	36,448	70,868
COMMITMENTS AND CONTINGENCIES (Note 8)
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	196,437
STOCKHOLDERS’ (DEFICIT) EQUITY:
Common stock, $0.0001 par value—83,000 and 100,000 shares authorized and 3,439 and 20,226 shares issued and outstanding as of December 31, 2017 and March 31, 2018, respectively	7	0
Additional paid-in capital	328,493	58,693
Accumulated other comprehensive income	558	1,066
Accumulated deficit	(288,500)	(268,445)
Total stockholders’ (deficit) equity	40,558	(208,686)
Total liabilities and stockholders’ (deficit) equity	157,807	100,758
Series G’ Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	44,672
Series G Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	5,110
Series F-R Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	58,449
Series E-R Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	29,972
Series D-R Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	32,728
Series C-R Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	18,366
Series B-R Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	0	5,288
Series A-R Stock
REDEEMABLE CONVERTIBLE PREFERRED STOCK:
Redeemable convertible preferred stock	$ 0	$ 1,852

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2018	Dec. 31, 2017
Common stock, par or stated value per share (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	100,000,000	83,000,000
Common stock, shares issued (in shares)	20,226,000	3,439,000
Common stock, shares outstanding (in shares)	20,226,000	3,439,000
Series G’ Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	5,339,000
Redeemable convertible preferred stock, shares issued (in shares)	0	1,295,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	1,295,000
Series G Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	1,385,000
Redeemable convertible preferred stock, shares issued (in shares)	0	346,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	346,000
Series F-R Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	5,000,000
Redeemable convertible preferred stock, shares issued (in shares)	0	1,199,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	1,199,000
Series E-R Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	7,400,000
Redeemable convertible preferred stock, shares issued (in shares)	0	795,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	795,000
Series D-R Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	5,787,000
Redeemable convertible preferred stock, shares issued (in shares)	0	1,396,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	1,396,000
Series C-R Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	6,032,000
Redeemable convertible preferred stock, shares issued (in shares)	0	1,508,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	1,508,000
Series B-R Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	9,596,000
Redeemable convertible preferred stock, shares issued (in shares)	0	2,247,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	2,247,000
Series A-R Stock
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	7,528,000
Redeemable convertible preferred stock, shares issued (in shares)	0	1,857,000
Redeemable convertible preferred stock, shares outstanding (in shares)	0	1,857,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
REVENUE	$ 32,713	$ 26,881
COSTS AND EXPENSES:
FI Share and other third-party costs	21,420	16,677
Delivery costs	1,943	1,553
Sales and marketing expense	8,216	7,232
Research and development expense	3,459	3,013
General and administration expense	6,582	4,689
Depreciation and amortization expense	910	765
Total costs and expenses	42,530	33,929
OPERATING LOSS	(9,817)	(7,048)
OTHER INCOME (EXPENSE):
Interest expense, net	(1,749)	(2,644)
Change in fair value of warrant liabilities, net	(9,172)	(327)
Change in fair value of convertible promissory notes	0	(383)
Change in fair value of convertible promissory notes—related parties	0	(2,223)
Other income, net	683	162
Total other expense	(10,238)	(5,415)
LOSS BEFORE INCOME TAXES	(20,055)	(12,463)
INCOME TAX BENEFIT	0	0
NET LOSS	(20,055)	(12,463)
Adjustments to the carrying value of redeemable convertible preferred stock	(157)	(244)
Net loss attributable to common stockholders	$ (20,212)	$ (12,707)
Net loss per share attributable to common stockholders, basic and diluted (in usd per share)	$ (1.54)	$ (4.80)
Weighted-average common shares outstanding, basic and diluted (in shares)	13,093	2,645

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
NET LOSS	$ (20,055)	$ (12,463)
OTHER COMPREHENSIVE LOSS:
Foreign currency translation adjustments	(508)	(120)
TOTAL COMPREHENSIVE LOSS	$ (20,563)	$ (12,583)

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ (DEFICIT) EQUITY (UNAUDITED) - 3 months ended Mar. 31, 2018 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2017		3,439
Beginning balance at Dec. 31, 2017	$ (208,686)	$ 0	$ 58,693	$ 1,066	$ (268,445)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options (in shares)	26	26
Exercise of common stock options	$ 108		108
Exercise of common stock warrants (in shares)		297
Stock-based compensation	2,906		2,906
Issuance of common stock in connection with our IPO (in shares)		5,821
Issuance of common stock in connection with our IPO	66,101	$ 1	66,100
Vesting of performance-based common stock warrants	2,519		2,519
Conversion of preferred stock to common stock (in shares)		10,643
Conversion of preferred stock to common stock	196,594	$ 6	196,588
Conversion of preferred stock warrants to common stock warrants	1,736		1,736
Accretion of redeemable convertible preferred stock to redemption value	(157)		(157)
Other comprehensive loss	(508)			(508)
Net loss	(20,055)				(20,055)
Ending balance (in shares) at Mar. 31, 2018		20,226
Ending balance at Mar. 31, 2018	$ 40,558	$ 7	$ 328,493	$ 558	$ (288,500)

CONDENSED CONSOLIDATED STATEME7

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
NET LOSS	$ (20,055)	$ (12,463)
Adjustments to reconcile net loss to net cash used in operating activities:
Change in allowance for doubtful accounts	(32)	(4)
Depreciation and amortization	910	765
Amortization of financing costs charged to interest expense	140	148
Accretion of debt discount and non-cash interest expense	1,500	2,307
Stock compensation expense	2,900	983
Change in the fair value of warrant liabilities, net	9,172	327
Change in the fair value of convertible promissory notes	0	383
Change in the fair value of convertible promissory notes - related parties	0	2,223
Other non-cash expenses	2,253	229
Change in operating assets and liabilities:
Accounts receivable	8,623	6,672
Prepaid expenses and other assets	(1,520)	(551)
Deferred FI implementation costs	1,094	962
Accounts payable	(408)	631
Other accrued expenses	(1,836)	(2,802)
FI Share liability	(2,538)	(4,643)
Customer Incentive liability	(293)	(991)
Total adjustment	19,965	6,639
Net cash used in operating activities	(90)	(5,824)
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisition of property and equipment	(418)	(386)
Acquisition of patents	(2)	(16)
Capitalized software development costs	(374)	0
Net cash used in investing activities	(794)	(402)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of debt	0	7,500
Principal payments of debt	(26)	(24)
Proceeds from issuance of common stock	70,490	270
Equity issuance costs	(1,232)	(181)
Net cash from financing activities	69,232	7,565
EFFECT OF EXCHANGE RATES ON CASH, CASH EQUIVALENTS AND RESTRICTED CASH	175	46
NET INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	68,523	1,385
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—beginning of period	21,262	22,968
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—end of period	89,785	24,353
Supplemental schedule of non-cash investing and financing activities:
Cash paid for interest	247	188
Amounts accrued for property and equipment	1,155	15
Amounts accrued for capitalized software development costs	141	0
Stock-based compensation capitalized for software development	$ 6	$ 0

OVERVIEW OF BUSINESS AND BASIS

OVERVIEW OF BUSINESS AND BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
OVERVIEW OF BUSINESS AND BASIS OF PRESENTATION	OVERVIEW OF BUSINESS AND BASIS OF PRESENTATION Cardlytics, Inc. (“we,” “our,” “us,” the “Company,” or “Cardlytics”) is a Delaware corporation and was formed on June 26, 2008. We make marketing more relevant and measurable through our purchase intelligence platform. Using one of the largest aggregations of purchase data through our partnerships with banks and credit unions, we have a secure view into where and when consumers are spending their money. By applying advanced analytics to this massive aggregation of anonymized purchase data, we make it actionable, helping marketers identify, reach and influence likely buyers at scale, and measure the true sales impact of their marketing spend. We operate in the United Kingdom through Cardlytics UK Limited, a wholly-owned and operated subsidiary registered as a private limited company in England and Wales. Initial Public Offering On February 13, 2018, we closed our initial public offering (“IPO”), in which we issued and sold 5,400,000 shares of common stock at a public offering price of $13.00 per share, resulting in gross proceeds of $70.2 million . On February 14, 2018, pursuant to the underwriters’ partial exercise of their over-allotment option to purchase up to an additional 810,000 shares from us, we issued and sold an additional 421,355 shares of our common stock, resulting in additional gross proceeds to us of $5.5 million . In total, we issued 5,821,355 shares of common stock and raised $75.7 million in gross proceeds, or $66.1 million in net proceeds after deducting underwriting discounts and commissions of $5.3 million and offering costs of $4.3 million . Upon the closing of the IPO, all of the outstanding shares of redeemable convertible preferred stock automatically converted into shares of common stock and all warrants to purchase shares of redeemable convertible preferred stock were automatically converted into warrants to purchase shares of common stock. Subsequent to the closing of the IPO, there were no shares of preferred stock or warrants to purchase shares of redeemable convertible preferred stock outstanding. The consolidated financial statements as of December 31, 2017, including share and per share amounts, do not give effect to the IPO or conversion of the redeemable convertible preferred stock, as the IPO and such conversions were completed subsequent to December 31, 2017. Reverse Stock Split On January 26, 2018, our board of directors approved an amended and restated certificate of incorporation to (1) effect a reverse split on outstanding shares of our common stock and redeemable convertible preferred stock on a one-for-four basis (the “Reverse Stock Split”), (2) modify the threshold for automatic conversion of our preferred stock into shares of our common stock in connection with an initial public offering to eliminate the requirement of gross proceeds to the Company of not less than $70.0 million and (3) authorize us to issue up to 100,000,000 shares of common stock, $0.0001 par value per share and 25,000,000 shares of redeemable convertible preferred stock, $0.0001 par value per share (collectively, the “Charter Amendment”). The authorized shares and par values of our common stock and redeemable convertible preferred stock were not adjusted as a result of the Reverse Stock Split. The Charter Amendment was approved by the Company’s stockholders on January 26, 2018 and became effective upon the filing of the Charter Amendment with the State of Delaware on January 26, 2018. All issued and outstanding common stock and preferred stock and related share and per share amounts contained in these financial statements have been retroactively adjusted to reflect the Reverse Stock Split for all periods presented. Unaudited Interim Results The accompanying unaudited interim condensed consolidated financial statements and information have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and in accordance with the rules and regulations of the Securities and Exchange Commission. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements. In the opinion of management, these financial statements contain all normal and recurring adjustments considered necessary to present fairly the financial position, results of operations, and cash flows for the periods presented. The results for interim periods presented are not necessarily indicative of the results to be expected for the full year due to the seasonality of our business which has been historically impacted by higher consumer spending during the fourth quarter. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes thereto included on our Annual Report on Form 10-K ("Annual Report") for the fiscal year ended December 31, 2017 . There have been no material changes to our accounting policies from those disclosed in the audited consolidated financial statements and related notes thereto included in our Annual Report for year ended December 31, 2017 . Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements. Significant items subject to such estimates and assumptions include revenue recognition, internal-use software development costs, income taxes, stock-based compensation, derivative instruments, income tax valuation allowance, contingencies and changes in fair value of our convertible promissory notes. We base our estimates on historical experience and also on assumptions that we believe are reasonable. Changes in facts or circumstances may cause us to change our assumptions and estimates in future periods and it is possible that actual results could differ from our current or revised future estimates.

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS	SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS Consumer Incentives Our Cardlytics Direct solution is our proprietary native bank advertising channel that enables marketers to reach consumers via email and through their trusted and frequently visited online and mobile banking channels. Working with the marketer, we design a campaign that targets customers based on their purchase history. The consumer is offered an incentive to make a purchase from the marketer within a specified period. We use a portion of the fees that we collect from marketers to provide these consumer incentives to our FIs’ customers after they make qualifying purchases, which we refer to as Consumer Incentives. We report our revenue on our condensed consolidated statements of operations net of Consumer Incentives. We generally pay Consumer Incentives only with respect to our Cardlytics Direct service. We do not provide the goods or services that are purchased by our FIs’ customers from the marketers to which the Consumer Incentives relate. Accordingly, the marketer is deemed to be the principal in the relationship with the customer and, therefore, the Consumer Incentive is deemed to be a reduction in the purchase price paid by the customer for the marketer’s goods or services. While we are responsible for remitting Consumer Incentives to our FI partners for further payment to their customers, we function solely as an agent of marketers in these arrangements. Accounts receivable is recorded at the amount of gross billings to marketers, net of allowances, for the fees and Consumer Incentives that we are responsible to collect. Our accrued liabilities also include the amount of Consumer Incentives due to FI partners. As a result, accounts receivable and accrued liabilities may appear large in relation to revenue, which is reported on a net basis. During the three months ended March 31, 2017 and 2018 , Consumer Incentives totaled $13.2 million and $16.0 million , respectively. Concentrations of Risk Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. Our cash and cash equivalents are held with two financial institutions, which we believe are of high credit quality. We believe that our accounts receivable credit risk exposure is limited as a result of being diversified among a large number of marketers segregated by both geography and industry. Historically, we have not experienced significant write-downs of our accounts receivable. One marketer represented 12% of our accounts receivable as of March 31, 2018. No other marketer represented a significant concentration of our accounts receivable as of December 31, 2017 or March 31, 2018, and no single marketer represented a significant concentration of our revenue during the three months ended March 31, 2017 or 2018. Our business is substantially dependent on a limited number of FI partners. We require participation from our FI partners in Cardlytics Direct and access to their purchase data in order to offer our solutions to marketers and their agencies. We must have FI partners with a sufficient number of customers and levels of customer engagement to ensure that we have robust purchase data and marketing space to support a broad array of incentive programs for marketers. Our agreements with a substantial majority of our FI partners have terms of three to five years but are terminable by the FI partner on 90 days or less prior notice. If an FI partner terminates its agreement with us, we would lose that FI as a source of purchase data and online banking customers. During both the three months ended March 31, 2017 and 2018, our largest FI partner in the U.S. accounted for approximately 69% of FI Share. No other FI partners accounted for over 10% of FI Share during the periods presented. Cash, Cash Equivalents and Restricted Cash Cash, cash equivalents and restricted cash as presented on our condensed consolidated statements of cash flows consists of the following (in thousands): December 31, March 31, 2016 2017 2017 2018 Cash and cash equivalents $ 22,838 $ 21,262 $ 24,353 $ 89,785 Restricted cash 130 — — — Cash, cash equivalents and restricted cash $ 22,968 $ 21,262 $ 24,353 $ 89,785 Deferred Offering Costs Deferred offering costs consist of incremental costs directly attributable to equity offerings. Deferred offering costs are included in other long-term assets on our condensed consolidated balance sheets. Upon completion of an offering, these amounts are offset against the proceeds of the offering. Three Months Ended 2017 2018 Beginning balance $ — $ 3,144 Deferred costs 776 1,135 Recognized against offering proceeds — (4,279 ) Ending balance $ 776 $ — Unpaid amounts as of March 31, 2018 totaled $0.7 million . Fair Value of Financial Instruments When required by U.S. GAAP, assets and liabilities are reported at fair value on our condensed consolidated financial statements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Valuation inputs are arranged in a hierarchy that consists of the following levels: • Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. • Level 2 inputs are inputs other than Level 1 inputs such as quoted prices for similar assets or liabilities; quoted prices in markets with insufficient volume or infrequent transactions (less active markets); or model-derived valuations in which all significant inputs are observable or can be derived principally from or corroborated by observable market data for substantially the full term of the assets or liabilities. • Level 3 inputs are unobservable inputs for the asset or liability. Our nonfinancial assets that we recognize or disclose at fair value on our condensed consolidated financial statements on a nonrecurring basis include property and equipment, intangible assets, capitalized software development costs and deferred FI implementation costs. The fair values for these assets are evaluated when events or changes in circumstances indicate the carrying value may not be recoverable. Preferred Stock Warrants Outstanding warrants to purchase shares of our redeemable convertible preferred stock are accounted for as derivative liabilities in accordance with ASC Topic 815, Derivatives and Hedging (“ASC 815”) due to the terms of the warrants and related agreements. We have determined that these warrants do not meet the scope exception of a contract indexed to our stock because of fair value protections contained in agreements governing our redeemable convertible preferred stock. We record preferred stock warrant liabilities on our condensed consolidated balance sheets at their fair value. We record the changes in fair value of such instruments as non-cash gains or losses on our condensed consolidated statements of operations. Upon our IPO, all warrants to purchase shares of our redeemable convertible preferred stock were converted to warrants to purchase shares of our common stock. See Note 6—Fair Value Measurements, for additional information regarding the valuation of warrants to purchase shares of our redeemable convertible preferred stock. Common Stock Warrants Issued in Connection with the Series G Stock Financing In connection with the Series G Stock financing, we issued warrants to purchase shares of our common stock that are accounted for as liabilities in accordance with ASC Topic 480, Distinguishing Liabilities From Equity due to the terms of the warrants and related agreements. We record these common stock warrant liabilities in our consolidated balance sheets at their fair value. We record the changes in fair value of such instruments as non-cash gains or losses in our statements of operations. See Note 6—Fair Value Measurements, for additional information regarding the valuation of the warrants issued in connection with the Series G Stock financing. Convertible Promissory Notes The redemption features included in the terms of the convertible promissory notes were determined to be derivative liabilities as a result of a significant discount within the redemption features for the note holders. Embedded derivatives that are not clearly and closely related to the host contract are required to be bifurcated and recorded at fair value unless the fair value option is elected on the host contract. Under the fair value option, bifurcation of the embedded derivative is not necessary as all related gains (losses) on the host contract and derivative will be reflected in the consolidated statements of operations. We elected the fair value option for the convertible promissory notes upon their issuance. The convertible promissory notes are measured using unobservable inputs that required a high level of judgment to determine fair value, and are therefore classified as Level 3. See Note 6—Fair Value Measurements for additional information regarding the valuation of the convertible promissory notes. Income Taxes On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (“Tax Act”) was signed into law making significant changes to the Internal Revenue Code. Changes include, but are not limited to, a corporate tax rate decrease to 21% effective for tax years beginning after December 31, 2017. This change in tax rate resulted in a reduction in our net U.S. deferred tax assets, which was fully offset by a reduction in our valuation allowance. The other provisions of the Tax Act, including the one-time transition tax on the mandatory deemed repatriation of cumulative foreign earnings, did not have a material impact on our financial statements as of December 31, 2017. As of December 31, 2017, pursuant to guidance provided in Staff Account Bulletin No. 118, we had not completed our accounting for the effects of the Tax Act; however, we made a reasonable estimate of the effects on our existing deferred tax balances and the one-time transition tax, including a provisional reduction in U.S. deferred tax assets, which was fully offset by a reduction in our valuation allowance. As of March 31, 2018, our accounting for the Tax Act is complete. No changes have been made to the provisional adjustments recorded as of December 31, 2017. Recently Adopted Accounting Pronouncements In May 2017, the FASB issued ASU 2017-09, Scope of Modification Accounting , which amends the scope of modification accounting for share-based payment arrangements, provides guidance on the types of changes to the terms or conditions of share-based payment awards to which an entity would be required to apply modification accounting under ASC Topic 718, Compensation—Stock Compensation . For all entities, the ASU is effective prospectively for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. We adopted this ASU on January 1, 2018 and it did not have an impact on our condensed consolidated financial statements. Recently Issued Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (Topic 606). ASU 2014-09 supersedes the recognition guidance in ASC Topic 605 and most industry specific revenue guidance and requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. In addition, this ASU requires disclosures of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. This ASU supersedes most existing GAAP revenue recognition principles, and it permits the use of either the retrospective or modified retrospective transition method. For public entities, this ASU is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods. For non-public entities, this ASU is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We have made the election to use the extended transition period for complying with new or revised accounting standards under Section 102(b)(1) of the Jumpstart Our Business Startups Act of 2012 ("JOBS Act"), therefore we will be required to apply this ASU for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Retrospective application will be required for each period presented through either the recasting of the prior periods for the effects of the adoption of this ASU or retrospectively through a cumulative catch up recognized at the date of adoption. During the first quarter of 2018, we began assessing the impacts, if any, that this ASU may have on our results of operations, current accounting policies, processes, controls, systems and financial statement disclosures. Based on our initial assessment, we expect to adopt this new standard using the modified retrospective transition method, which would result in a cumulative adjustment as of the date of the adoption. In January 2016, the FASB issued ASU 2016-01, Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which is intended to enhance the reporting model for financial instruments to provide users of financial statements with more decision-useful information. This ASU requires equity investments to be measured at fair value with changes in fair values recognized in net earnings, (public entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes), simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment and eliminates the requirement to disclose fair values, the methods and significant assumptions used to estimate the fair value of financial instruments measured at amortized cost. This ASU also clarifies that management should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale debt securities in combination with other deferred tax assets. For public business entities, this ASU is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods. For non-public business entities, this ASU is effective for fiscal years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. Early adoption is permitted. We have made the election to use the extended transition period for complying with new or revised accounting standards under Section 102(b)(1) of the JOBS Act, therefore we will be required to apply this ASU for annual reporting periods beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. We are currently evaluating the potential impact of this recently issued guidance on our condensed consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which supersedes ASC Topic 840, Leases . The ASU does not significantly change the lessees’ recognition, measurement and presentation of expenses and cash flows from the previous accounting standard. The ASU’s primary change is the requirement for lessee entities to recognize a lease liability for payments and a right of use asset representing the right to use the leased asset during the term on operating lease arrangements. Lessees are permitted to make an accounting policy election to not recognize the asset and liability for leases with a term of twelve months or less. Lessors’ accounting under the ASU is largely unchanged from the previous accounting standard. In addition, the ASU expands the disclosure requirements of lease arrangements. Lessees and lessors will use a modified retrospective transition approach. For public entities, this ASU is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. For non-public entities, this ASU is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. We have made the election to use the extended transition period for complying with new or revised accounting standards under Section 102(b)(1) of the JOBS Act, therefore we will be required to adopt this ASU for annual reporting periods beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted. Although we are currently evaluating the impact of this guidance on our condensed consolidated financial statements, we expect that most of our operating lease commitments will be recognized as operating lease liabilities and right-of-use assets upon adoption of the new guidance.

DEBT

DEBT	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
DEBT	DEBT Our debt consists of the following (in thousands): December 31, 2017 March 31, 2018 Line of credit $ 25,081 $ 25,634 Term loan, net of unamortized discount and debt issuance costs of $1,058 and $889 at December 31, 2017 and March 31, 2018, respectively 31,830 32,842 Capital leases 101 75 Convertible promissory notes (converted into Series G' Stock in May 2017) — — Total debt $ 57,012 $ 58,551 Less short-term debt (44 ) (25,657 ) Long-term debt, net of current portion $ 56,968 $ 32,894 Accrued interest included in debt totaled $6.2 million and $7.6 million as of December 31, 2017 and March 31, 2018 , respectively. Line of Credit In September 2016, we entered into a loan and security agreement (“Line of Credit”) that matures on March 14, 2019. Maximum borrowings are stated as the lesser of $50.0 million or 85% of our eligible accounts receivable. The Line of Credit is collateralized by substantially all of our assets and carries a floating interest rate equal to the Prime Rate in effect plus 3.50% , not to be less than 7.0% per year. Fees include an unused line fee of 0.50% and an annual administrative fee of less than $0.1 million . Interest and fees under the Line of Credit may be added to the principal balance of the loan due and payable at maturity. Amounts outstanding under the Line of Credit are classified as short-term. We capitalized $0.7 million of debt issuance costs associated with obtaining the Line of Credit. The Line of Credit includes customary affirmative and negative covenants, including restrictions on mergers, acquisitions and dispositions of assets, incurrence of indebtedness and encumbrances on our assets and restrictions on payments of dividends. We are also required to maintain a total cash balance plus liquidity under the Line of Credit of not less than $5.0 million and maintain a moving minimum twelve -month revenue throughout the term of the Line of Credit, with minimum revenue of at least $123.3 million for the twelve months ending March 31, 2018 . We were in compliance with all financial covenants as of March 31, 2018 . As of March 31, 2018 , we had $4.9 million of unused available borrowings under our Line of Credit. We expect to refinance or obtain a similar line of credit prior to its maturity date. In the event we are unable to refinance or obtain a similar line of credit under acceptable terms, we could repay our Line of Credit at or before its maturity. Term Loan In July 2016, we entered into a $24.0 million credit agreement (“Term Loan”) that matures on July 21, 2019. The Term Loan is secured by substantially all of our assets and carries a fixed interest rate equal to (1) 13.25% , of which 3% is payable in cash and the remaining 10.25% is payable in-kind, (2) 12.75% , subsequent to an IPO with gross proceeds of at least $75.0 million , of which 3% is payable in cash and the remaining 9.75% is payable in-kind or (3) 11.25% , if our adjusted EBITDA for the four most recent trailing fiscal quarters then-ended is greater than $1.0 million and we are not in an event of default, of which 3% is payable in cash and the remaining 8.25% is payable in-kind. The lender funded an initial loan of $19.0 million at closing and a subsequent loan of $5.0 million in November 2016 when the amount became available upon achieving trailing- four quarter revenue of $100.0 million . In April 2017, we amended our Term Loan to remove the acceleration of our repayment upon IPO and reduce the interest rate by 0.5% subsequent to an IPO. In June 2017, we amended and restated our Term Loan and borrowed an additional $5.0 million . The Term Loan contains customary affirmative and negative covenants, including restrictions on mergers, acquisitions and dispositions of assets, incurrence of indebtedness and encumbrances on our assets and restrictions on payments of dividends. The Term Loan also requires us to maintain a total cash balance and unrestricted availability under our Line of Credit of not less than $3.0 million . Once we have achieved an adjusted EBITDA of at least $1.0 million for two consecutive fiscal quarters, this requirement will be permanently waived. The Term Loan contains customary event of default provisions, including in the event of a change of control, the occurrence of which could lead to an acceleration of our obligations under the Term Loan. Pursuant to the Term Loan, in July 2016, we issued ten -year warrants to purchase up to an aggregate of 97,125 shares of our common stock at an exercise price of $20.00 per share. The fair value of the warrants was calculated to be $1.0 million under the Black-Scholes option pricing model. In June 2017, we issued additional ten -year warrants to purchase up to an aggregate of 17,500 shares of common stock at a price per share of $27.68 . The fair value of the warrants was calculated to be $0.3 million under the Black-Scholes option pricing model. Under the guidance provided by ASC Topic 470-20, Debt with Conversion and Other Options , proceeds from the sale of debt instruments with stock purchase warrants are allocated to the two elements based on the relative fair values of the debt instrument without the warrants and of the warrants themselves at time of issuance. The portion of the proceeds allocated to the warrants is accounted for as paid-in capital, as the warrants meet the scope exception within ASC 815 and are considered indexed to the Company’s own stock and accounted for as equity. The remainder of the proceeds is allocated to the debt instrument portion of the transaction. We were in compliance with all financial covenants as of March 31, 2018 . We expect to refinance or obtain a similar loan prior to its maturity date. In the event we are unable to refinance or obtain a similar loan under acceptable terms, we could repay our Term Loan at or before its maturity. Convertible Promissory Notes During 2016, we issued unsecured convertible promissory notes with an aggregate principal amount of $50.7 million . In May 2017, we issued and sold shares of Series G redeemable convertible preferred stock, which resulted in the conversion of the convertible promissory notes into either shares of our common stock or shares of our Series G’ Stock. See Note 5—Redeemable Convertible Preferred Stock for a description of the Series G Stock financing that resulted in the conversion of the convertible promissory notes. The redemption features included in the terms of the convertible promissory notes were determined to be derivative liabilities as a result of a significant discount within the redemption features for the note holders. Embedded derivatives that are not clearly and closely related to the host contract are required to be bifurcated and recorded at fair value unless the fair value option is elected on the host contract. Under the fair value option, bifurcation of the embedded derivative is not necessary as all related gains (losses) on the host contract and derivative will be reflected in the consolidated statements of operations. We elected the fair value option for the convertible promissory notes and recognized losses from their initial measurement during the second and third quarters of 2016. Subsequent changes in fair value of the convertible promissory notes are included in change in fair value of convertible promissory notes on our condensed consolidated statements of operations. See Note 6—Fair Value Measurements for additional information regarding the valuation of the convertible promissory notes. Paid-in-kind interest related to the convertible promissory notes is recognized in interest expense, net on our condensed consolidated statements of operations and totaled $1.2 million during the three months ended March 31, 2017 . Future Payments Aggregate future payments of principal and interest due upon maturity are as follows (in thousands): Years Ending December 31, Debt Capital Leases Total Debt 2018 (remainder of year) $ — $ 18 $ 18 2019 59,365 20 59,385 2020 — 24 24 2021 — 13 13 Total principal payments $ 59,365 $ 75 $ 59,440 Less unamortized debt issuance costs (274 ) — (274 ) Less unamortized debt discount (615 ) — (615 ) Total debt $ 58,476 $ 75 $ 58,551

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION In May 2017, our board of directors and stockholders approved an increase in the total number of shares of common stock issuable under our 2008 Stock Plan ("2008 Plan") from 3,120,000 to 3,495,000 shares. In January 2018, our board of directors and stockholders approved an increase in the total number of shares of common stock issuable under our 2008 Plan to 4,020,000 shares. Our board of directors has adopted and our stockholders have approved our 2018 Equity Incentive Plan ("2018 Plan"). Our 2018 Plan became effective on February 8, 2018, the date our registration statement in connection with our IPO was declared effective. We do not expect to grant any additional awards under the 2008 Stock Plan. Any awards granted under the 2008 Plan will remain subject to the terms of our 2008 Plan and applicable award agreements. Initially, the aggregate number of shares of our common stock that may be issued pursuant to stock awards under the 2018 Plan is the sum of (i) 1,875,000 shares plus (ii) 61,247 shares reserved, and remaining available for issuance, under our 2008 Plan at the time our 2018 Plan became effective and (iii) the number of shares subject to stock options or other stock awards granted under our 2008 Plan that would have otherwise returned to our 2008 Plan (such as upon the expiration or termination of a stock award prior to vesting). The number of shares of our common stock reserved for issuance under our 2018 Plan will automatically increase on January 1 of each year, beginning on January 1, 2019 and continuing through and including January 1, 2028, by 5% of the total number of shares of our capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by our board of directors. The 2018 Plan provides for the grant of stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance-based stock awards and other forms of equity compensation, which are collectively referred to as stock awards. Additionally, the 2018 Plan provides for the grant of performance cash awards. The following table summarizes the allocation of stock-based compensation in the consolidated statements of operations (in thousands): Three Months Ended 2017 2018 Delivery costs $ 41 $ 85 Sales and marketing expense 344 943 Research and development expense 171 470 General and administration expense 427 1,402 Total stock-based compensation expense $ 983 $ 2,900 Common Stock Options Options to purchase shares of common stock generally vest over four years and expire 10 years following the date of grant. A summary of common stock option activity is as follows (in thousands, except per share amounts): Shares Weighted-Average Exercise Price Options outstanding — December 31, 2016 2,137 $ 15.00 Granted 124 11.81 Exercised (76 ) 3.57 Forfeited (9 ) 20.59 Cancelled (6 ) 14.21 Options outstanding — March 31, 2017 2,170 $ 15.20 Shares Weighted-Average Exercise Price Options outstanding — December 31, 2017 2,514 $ 18.42 Granted 29 24.24 Exercised (26 ) 4.22 Forfeited (103 ) 25.65 Cancelled (35 ) 15.88 Options outstanding — March 31, 2018 2,379 $ 18.37 The weighted-average grant-date fair value of options granted during the three months ended March 31, 2017 and 2018 was $7.32 and $10.00 . respectively. The total fair value of options vested during the three months ended March 31, 2017 and 2018 was approximately $0.6 million and $1.2 million , respectively. As of March 31, 2018 , $10.4 million of unrecognized compensation expense related to unvested options will be recognized over a weighted-average period of 2.7 years. Restricted Stock Units A summary of restricted stock unit activity is as follows (in thousands, except per share amounts): Shares Weighted-Average Grant Date Fair Value Unvested — December 31, 2017 — $ — Granted 1,210 20.80 Vested — — Forfeited (2 ) 16.80 Unvested — March 31, 2018 1,208 $ 20.81 During the first quarter of 2018, we granted 335,562 restricted stock units ("RSUs") to employees and our non-employee directors, which have annual vesting periods ranging from one to four years. We also granted two separate tranches of performance-based restricted share units ("PSUs") to receive 437,500 shares of common stock to employees. The vesting of the PSUs was contingent upon the completion of our IPO and includes other performance-based conditions. The performance condition in the first tranche will be satisfied if we attain 70.0 million of FI monthly active users ("FI MAUs") within three years of the grant date. The performance condition in the second tranche will be satisfied if we attain 85.0 million of FI MAUs within five years of the grant date. FI MAUs is a performance metric defined within "Management's Discussion and Analysis of Financial Condition and Results of Operations." As of March 31, 2018, there was approximately $24.3 million of unrecognized compensation expense related to restricted stock units, which is expected to be recognized over a weighted-average period of 4.3 years. During the second quarter of 2018, we granted 32,070 RSUs to employees, which have annual vesting periods of four years. The unamortized stock-based compensation expense related to these RSUs is $0.5 million , which will be recognized as stock-based compensation expense over the vesting periods of the awards. Restricted Securities Units During 2016, we granted $1.0 million of restricted securities units to certain executives in lieu of cash bonuses. Upon issuance, the restricted securities units were indexed to the convertible promissory notes. As a result of the Series G Stock financing, the restricted securities units became indexed to our Series G’ Stock on the same terms as the Series G’ Stock issued upon conversion of the convertible promissory notes. Upon the completion of our IPO in February 2018, the restricted securities units became indexed to our common stock. Vesting requirements include both a service-based condition and a performance-based condition. The service-based condition requires each recipient to remain employed until the earlier of i) the date 6 months from the restricted securities unit grant date, ii) the date of a qualified liquidity event, or iii) date of termination without cause. The performance-based condition requires a sale of the Company or IPO event within a fixed period of time not more than 5 years from the restricted securities units grant date. The restricted securities units are considered liability classified awards, but due to the performance condition relating to sale of the Company or IPO, no compensation cost was recognized until one of these events occured. These warrants vested upon the completion of our IPO in February 2018 resulting in a non-cash expense of $0.5 million . Employee Stock Purchase Plan Our board of directors has adopted and our stockholders have approved our 2018 Employee Stock Purchase Plan ("2018 ESPP"). Our 2018 ESPP became effective on February 8, 2018, the date our registration statement in connection with our IPO was declared effective and enables eligible employees to purchase shares of our common stock at a discount. Purchases will be accomplished through participation in discrete offering periods. On each purchase date, eligible employees will purchase our common stock at a price per share equal to 85% of the lesser of the fair market value of our common stock on the first trading day of the offering period or the date of purchase. No shares of common stock have been purchased under the 2018 ESPP as the initial offering period has not yet ended. The maximum number of shares of our common stock that may be issued under our 2018 ESPP is 375,000 shares. Additionally, the number of shares of our common stock reserved for issuance under our 2018 ESPP will automatically increase on January 1 of each year, beginning on January 1, 2019 and continuing through and including January 1, 2026, by the lesser of (i) 1% of the total number of shares of our common stock outstanding on December 31 of the preceding calendar year, (ii) 500,000 shares of our common stock or (iii) such lesser number of shares of common stock as determined by our board of directors. Shares subject to purchase rights granted under our 2018 ESPP that terminate without having been exercised in full will not reduce the number of shares available for issuance under our 2018 ESPP.

REDEEMABLE CONVERTIBLE PREFERRE

REDEEMABLE CONVERTIBLE PREFERRED STOCK	3 Months Ended
	Mar. 31, 2018
Temporary Equity Disclosure [Abstract]
REDEEMABLE CONVERTIBLE PREFERRED STOCK	REDEEMABLE CONVERTIBLE PREFERRED STOCK Upon the consummation of our IPO, all of the outstanding shares of redeemable convertible preferred stock were automatically converted into shares of common stock. See Note 1—Overview of Business and Basis of Presentation for additional information regarding our IPO. A summary of the change in carrying amount of the outstanding redeemable convertible preferred stock is as follows (in thousands): Series G’ Stock Series G Stock Shares Amount Shares Amount Balance — December 31, 2017 1,295 $ 44,672 346 $ 5,110 Accretion of redeemable convertible preferred stock — — — 108 Conversion of preferred stock to common stock (1,295 ) (44,672 ) (346 ) (5,218 ) Balance — March 31, 2018 — $ — — $ — Series F-R Stock Series E-R Stock Series D-R Stock Shares Amount Shares Amount Shares Amount Balance — December 31, 2017 1,199 $ 58,449 795 $ 29,972 1,396 $ 32,728 Accretion of redeemable convertible preferred stock — 38 — 1 — 7 Conversion of preferred stock to common stock (1,199 ) (58,487 ) (795 ) (29,973 ) (1,396 ) (32,735 ) Balance — March 31, 2018 — $ — — $ — — $ — Series C-R Stock Series B-R Stock Series A-R Stock Shares Amount Shares Amount Shares Amount Balance — December 31, 2017 1,508 $ 18,366 2,247 $ 5,288 1,857 $ 1,852 Accretion of redeemable convertible preferred stock — 3 — — — — Conversion of preferred stock to common stock (1,508 ) (18,369 ) (2,247 ) (5,288 ) (1,857 ) (1,852 ) Balance — March 31, 2018 — $ — — $ — — $ — During the second quarter of 2016, we issued convertible promissory notes to our founders and the existing holders of our redeemable convertible preferred stock. Shares of redeemable convertible preferred stock held by investors that participated in the financing were exchanged for shares of replacement preferred stock. These replacement shares have rights and preferences equal to their corresponding original series and are designated as Series A-R Stock, Series B-R Stock, Series C-R Stock, Series D-R Stock, Series E-R Stock and Series F-R Stock. Shares of redeemable convertible preferred stock held by investors that did not participate in the financing were converted to common stock. In February 2017, we amended and restated our certificate of incorporation reducing the authorized number of shares of our redeemable convertible preferred stock to 82,683,212 and cancelled Series A Stock, Series B Stock, Series C Stock, Series D Stock, Series E Stock and Series F Stock. Pursuant to our convertible promissory note financing, these series of preferred stock were either exchanged for shares of replacement preferred stock with rights and preferences equal to their corresponding original series or converted to common stock. Series G Stock Financing In May 2017, we amended and restated our certificate of incorporation and increased the authorized number of shares of our common stock to 83,000,000 and increased the authorized number of shares of our redeemable convertible preferred stock to 96,131,002 . In May 2017, we issued and sold, for aggregate consideration of $11.9 million , an aggregate of 346,334 shares of Series G redeemable convertible preferred stock, par value $0.0001 per share with a stated price of $34.4758 per share (“Series G Stock”), and warrants to purchase shares of our common stock. Issuance costs incurred in connection with the sale of Series G Stock totaled $0.1 million . Conversion of Convertible Promissory Notes into Series G’ Stock In connection with the Series G Stock financing in May 2017, certain convertible promissory notes converted into 1,295,746 shares of Series G’ redeemable convertible preferred stock, par value $0.0001 per share (“Series G’ Stock”), at a price per share of $2.758 . Common Stock Warrants Issued in Connection with the Series G Stock Financing In connection with the Series G Stock financing, we issued warrants to purchase an aggregate of number of shares of common stock equal to the product obtained by multiplying 346,334 by a fraction, the numerator of which is the difference between $68.9516 and the volume weighted average closing price of our common stock over the 30 trading days (or such lesser number of days as our common stock has been traded on the Nasdaq Global Market) prior to the date on which such warrants vest and become exercisable and the denominator of which is such volume weighted average closing price, which warrants will become vested and exercisable upon the earlier to occur of the date (i) August 8, 2018, which is 180 days following the date of our IPO and (ii) 10 days prior to a sale of our company, at an exercise price of $0.0004 per share. See Note 6—Fair Value Measurements, for additional information regarding the valuation of the warrants issued in connection with the Series G Stock financing. Beneficial conversion feature The aggregate proceeds of $11.9 million from the Series G Stock financing were first allocated to the warrants to purchase shares of our common stock, which qualify as liabilities under ASC 480 and are recorded at fair value, with the residual value of $4.5 million allocated to our Series G Stock. As a result of this allocation, Series G Stock was determined to contain a beneficial conversion feature with an intrinsic value of $6.1 million . The amount assigned to the beneficial conversion feature was limited to the $4.5 million residual value allocated to Series G Stock and is classified as a component of additional paid-in capital. During the second quarter of 2017, we recorded a deemed dividend of $4.5 million related to the beneficial conversion feature, which is reflected below net loss to arrive at net loss available to common stockholders.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
FAIR VALUE MEASURMENTS	FAIR VALUE MEASUREMENTS Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The following table summarizes our liabilities measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): December 31, 2017 Level 1 Level 2 Level 3 Total Liabilities: Preferred stock warrants $ — $ — $ 2,285 $ 2,285 Common stock warrants — — 7,945 7,945 Convertible promissory notes — — — — Total liabilities $ — $ — $ 10,230 $ 10,230 March 31, 2018 Level 1 Level 2 Level 3 Total Liabilities: Preferred stock warrants $ — $ — $ — $ — Common stock warrants — — 17,666 17,666 Convertible promissory notes — — — — Total liabilities $ — $ — $ 17,666 $ 17,666 Instruments Recorded at Fair Value Using Level 3 Inputs Our redeemable convertible preferred stock warrants, common stock warrants issued in connection with the Series G Stock financing and our convertible promissory notes are measured and recorded at fair value on a recurring basis using Level 3 inputs. The table below provides a roll forward of the changes in fair value of Level 3 financial instruments (in thousands): Preferred Stock Warrants Common Stock Warrants Convertible Promissory Notes Balance at December 31, 2016 $ 2,197 $ — $ 72,332 Accrued interest on convertible promissory notes — — 1,246 Changes in fair value 327 — 2,606 Balance at March 31, 2017 $ 2,524 $ — $ 76,184 Preferred Stock Warrants Common Stock Warrants Convertible Promissory Notes Balance at December 31, 2017 $ 2,285 $ 7,945 $ — Changes in fair value (549 ) 9,721 — Conversion of preferred stock warrants to common stock warrants (1,736 ) — — Balance at March 31, 2018 $ — $ 17,666 $ — In valuing our instruments recorded at fair value using Level 3 inputs, our board of directors determined the equity value of our business generally using a combination of the income approach and the market approach valuation methods. The income approach estimates value based on the expectation of future cash flows that a company will generate, such as cash earnings, cost savings, tax deductions and the proceeds from disposition. These future cash flows are discounted to their present values using a discount rate derived based on an analysis of the cost of capital of comparable publicly traded companies in similar lines of business, as of each valuation date, and is adjusted to reflect the risks inherent in our cash flows. The market approach estimates the fair value of a company by applying market multiples of comparable publicly traded companies in a similar line of business. The market multiples are based on relevant metrics implied by the price that investors have paid for the equity of publicly traded companies. Given our significant focus on investing in and growing our business, we primarily utilized the forward-looking revenue multiple when performing valuation assessments under the market approach and considered both trading and transaction multiples. When considering which companies to include as our comparable industry peer companies, we focused on U.S.-based publicly traded companies that were broadly comparable to us based on consideration of industry, market and line of business. From the comparable companies, a representative market value multiple was determined and applied to our operating results to estimate the value of our company. The market value multiple was determined based on consideration of multiples of revenue to each of the comparable companies’ historical and forecasted revenue. In addition, the market approach considers IPO and merger and acquisition transactions involving companies similar to the company’s business being valued. Multiples of revenue are calculated for these transactions and then applied to the business being valued, after reduction by an appropriate discount. Once an equity value was determined, we utilized the option pricing method ("OPM"), or probability-weighted expected return method (“PWERM”) to allocate the overall value of equity to the various share classes. The OPM was used in valuations as of and for dates prior to December 31, 2016 and the PWERM was used in all subsequent valuations. The OPM treats common stock and convertible preferred stock as call options on a company’s enterprise value with exercise prices based on the liquidation preferences of the convertible preferred stock. Under this method, the common stock only has value if the funds available for distribution to stockholders exceed the value of the liquidation preference at the time of an assumed liquidity event. The value assigned to the common stock is the remaining value after the convertible preferred stock is liquidated. The OPM prices the call option using the Black-Scholes model. The PWERM relies on a forward-looking analysis to predict the possible future value of a company. Under this method, discrete future outcomes, including an IPO and non-IPO scenarios, are weighted based on the estimated the probability of each scenario. The PWERM is used when discrete future outcomes can be predicted with reasonable certainty based on a probability distribution. We relied on the PWERM to allocate the value of equity under a liquidity scenario. The projected equity value relied upon in the PWERM scenario was based on (i) guideline IPO transactions involving companies that were considered broadly comparable to us and (ii) our expectation of the pre-money valuation that we needed to achieve to consider an IPO as a viable exit strategy. The following table summarizes key assumptions used in the PWERM for estimating the fair value of our redeemable convertible preferred stock warrant liability and convertible promissory notes: March 31, 2017 Cost of debt applicable to convertible promissory notes 10% Cost of equity applicable to convertible promissory notes 22% Weighted-average cost of capital applicable to preferred stock warrants 23% Discount for lack of marketability 7% to 11% Volatility 53% Risk-free interest rate 0.7% to 1.2% Preferred Stock Warrants A summary of our preferred stock warrants is as follows (in thousands, except per share amounts): Preferred Series Grant date Expiration date Exercise price December 31, 2017 March 31, 2018 Series B-R 2/26/2010 2/25/2020 $ 2.36 59 — Series D-R 9/21/2012 9/20/2022 $ 23.64 38 — Series D-R 9/21/2012 9/20/2022 $ 23.64 13 — Total 110 — The fair value of the warrants to purchase Series B-R Stock and Series D-R Stock decreased from $26.80 per share and $13.63 per share on December 31, 2017 to $20.18 per share and $10.57 per share on February 8, 2018, respectively, the date at which they converted to warrants to purchase shares of our common stock and were reclassified to additional paid-in capital on our condensed consolidated balance sheet. The decrease in the fair value of the warrants to purchase Series B-R Stock and Series D-R Stock primarily resulted from the timing of future potential liquidity events, changes to our forecasted financial results and changes in the valuation of comparable companies. Common Stock Warrants Issued in Connection with the Series G Stock Financing In connection with the Series G Stock financing, we issued warrants to purchase an aggregate number of shares of common stock equal to the product obtained by multiplying 346,334 by a fraction, the numerator of which is the difference between $68.9516 and the volume weighted average closing price of our common stock over the 30 trading days (or such lesser number of days as our common stock has been traded on the Nasdaq Global Market) prior to the date on which such warrants vest and become exercisable and the denominator of which is such volume weighted average closing price, which warrants will become vested and exercisable upon the earlier to occur of the date (i) August, 8, 2018, which is 180 days following the date of our IPO and (ii) 10 days prior to a sale of our company, at an exercise price of $0.0004 per share. To determine the fair value of our common stock warrant liability issued in connection with our Series G Stock financing, we utilized a Monte Carlo simulation, which allows for the modeling of complex securities and evaluates many possible outcomes to forecast the stock price of the company post-IPO. As part of the valuation, we considered various scenarios related to the pricing, timing and probability of an IPO. We applied an annual equity volatility of 59% and a discount for lack of marketability of 11% to arrive at a valuation of $7.5 million on the issuance date. Subsequent to our IPO, the fair value of the common stock warrant liability is estimated based on the fair market value of our common stock at each reporting period, discounted from the date of settlement, which is expected to be 180 days following the date of our IPO. The valuation as of March 31, 2018 was determined to be $17.7 million . As a result, during the three months ended March 31, 2018 , we recorded a non-cash loss of $9.7 million related to the change in fair value of our common stock warrant liability. Convertible Promissory Notes The redemption features included in the terms of the convertible promissory notes were determined to be derivative liabilities due to a significant discount within the redemption features for the note holders. Embedded derivatives that are not clearly and closely related to the host contract are required to be bifurcated and recorded at fair value unless the fair value option is elected on the host contract. Under the fair value option, bifurcation of the embedded derivative is not necessary as all related gains (losses) on the host contract and derivative will be reflected in the consolidated statements of operations. We elected the fair value option for the convertible promissory notes, therefore direct costs and fees associated with the issuance were recognized in earnings as incurred and were not deferred. To determine the fair value of our convertible promissory notes through their conversion in May 2017, we utilized key assumptions from the PWERM, as shown above. Under this method, we considered the redemption features of the convertible promissory notes to determine the fair value under discrete future outcomes, including IPO and non-IPO scenarios. Under certain non-IPO scenarios, holders of the convertible promissory notes will receive two times preference on the outstanding principal amount. We weighted the fair values based on the estimated probability of each scenario to determine the overall fair value of the convertible promissory notes as of the balance sheet date. See Note 5—Redeemable Convertible Preferred Stock for a description of the Series G Stock financing in May 2017 that resulted in the conversion of the convertible promissory notes into shares of our Series G’ Stock. Performance-based Warrants Issued to FIS In May 2013, we granted 10 -year performance-based warrants to purchase up to 644,365 shares of Series E Stock at an exercise price of $23.64 per share. Since FIS did not participate in the convertible promissory note financing, their warrants to purchase preferred stock were converted to warrants to purchase common stock. The warrants vested upon the completion of our IPO in February 2018 resulting in a non-cash expense of $2.5 million . We determined the fair value of these common warrants on the date of IPO using the Black-Scholes option pricing model, which is affected by the fair value of our common stock as well as the following significant inputs: Performance-based warrants (vested upon IPO) Weighted-average grant date fair value $3.91 Significant inputs: Value of common stock $13.00 Expected term 5.3 years Volatility 50% Risk-free interest rate 2.0% Dividend yield —%

RELATED PARTIES

RELATED PARTIES	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
RELATED PARTIES	RELATED PARTIES Series G / Series G’ In May 2017, we issued and sold, for aggregate consideration of $11.9 million , an aggregate of 346,334 shares of our Series G Stock and warrants to purchase shares of our common stock. In connection with the issuance of our Series G Stock, the principal and accrued interest under the convertible promissory notes converted into an aggregate of 1,295,746 shares of our Series G’ redeemable convertible preferred stock and 801,329 shares of our common stock. The following table summarizes the participation in the foregoing transactions by our directors, executive officers and holders of more than 5% of any class of our capital stock as of the date of such transactions (in thousands): Related Party Shares of Series G Preferred Stock Shares of Series G’ Preferred Stock Shares of Common Stock Warrants to Purchase Common Stock Entities affiliated with Aimia, Inc. (1) — 382 801 — Entities affiliated with Polaris Venture Partners (2) 29 212 — (6 ) Canaan VIII L.P. (3) 54 260 — (6 ) Entities affiliated with Discovery Capital (4) — 106 — — Scott D. Grimes — 26 — — Lynne M. Laube — 14 — — Entities affiliated with Mark A. Johnson (5) 35 15 — (6 ) John Klinck 6 — — (6 ) David Adams 3 — — (6 ) (1) Consists of 159,207 shares of Series G’ redeemable convertible preferred stock issued to Aeroplan Holdings Europe Sàrl, 223,020 shares of Series G’ redeemable convertible preferred stock issued to Aimia EMEA Limited and 801,329 shares of common stock issued to Aimia EMEA Limited. (2) Consists of 27,988 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners V, L.P. (“PVP V”), 205,020 shares of Series G’ redeemable convertible preferred stock issued to PVP V, 545 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners Entrepreneurs’ Fund V, L.L. (“PVP EF V”), 3,995 shares of Series G’ redeemable convertible preferred stock issued to PVP EF V, 191 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners Founders’ Fund V, L.P. (“PVP FF V”), 1,404 shares of Series G’ redeemable convertible preferred stock issued to PVP FF V, 280 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners Special Founders’ Fund V, L.P. (“PVP SFF V”) and 2,050 shares of Series G’ redeemable convertible preferred stock issued to PVP SFF V. Polaris Venture Management Co. V, L.L.C. is a general partner of each of PVP V, PVP EF V, PVP FF V and PVP SFF V and may be deemed to have the sole voting and dispositive power over the shares held by PVP V, PVP EF V, PVP FF V and PVP SFF V. Bryce Youngren, a member of our board of directors, is a Managing Partner of Polaris Partners and may be deemed to share voting and dispositive power over the shares held by PVP V, PVP EF V, PVP FF V and PVP SFF V. (3) John V. Balen, a member of our board of directors, is a managing member of Canaan Partners VIII LLC, the general partner of Canaan VIII L.P. Mr. Balen does not have voting or investment power over any shares held directly by Canaan VIII L.P. (4) Consists of 95,272 shares of Series G’ redeemable convertible preferred stock issued to Discovery Opportunity Master Fund, Ltd. and 11,072 shares of Series G’ redeemable convertible preferred stock issued to Discovery Global Focus Master Fund, Ltd. (5) Consists of 15,045 shares of Series G’ redeemable convertible preferred stock issued to TTP Fund II, L.P., 29,005 shares of Series G redeemable convertible preferred stock purchased by TTV Ivy Holdings, LLC and 5,801 shares of Series G redeemable convertible preferred stock purchased by Mr. Johnson. TTV Capital is a provider of management services to TTP GP II, LLC, which is a general partner of TTP Fund II, L.P. TTV Capital is the manager of TTV Ivy Holdings Manager, LLC, which is the general partner of TTV Ivy Holdings, LLC. Mark A. Johnson, a member of our board of directors, is a member of each of TTP GP II, LLC and TTV Ivy Holdings Managers, LLC and holds the title of partner of TTV Capital, and may be deemed to share voting and dispositive power over the shares held by TTP Fund II L.P. and TTV Ivy Holdings, LLC. (6) The maximum number of shares issuable to each investor upon the exercise of such warrants is equal to the number of shares of Series G redeemable convertible preferred stock set forth opposite such investor’s name in the table above. The actual number of shares issuable to each investor upon the exercise of such warrants is equal to the product obtained by multiplying the number of shares of Series G redeemable convertible preferred stock set forth opposite such investor’s name in the table above by a fraction, the numerator of which is the difference between $68.9516 and the volume weighted average closing price of our common stock over the 30 trading days (or such lesser number of days as our common stock has been traded on the Nasdaq Global Market) prior to the date on which such warrants become exercisable and the denominator of which is such volume weighted average closing price. Agreements with Fidelity Information Services, LLC We are party to a reseller agreement with Fidelity Information Services LLC (“FIS”). Pursuant to the reseller agreement, FIS markets and sells our services to financial institutions that are current or potential customers of FIS in exchange for a revenue share percentage. We are also obligated to make milestone payments to FIS related to the integration and deployment of our solutions. See Note 8—Commitments and Contingencies for additional information. Prior to our IPO, FIS was entitled to elect a member of our board of directors, who was Robert Legters until his resignation immediately prior to our IPO in February 2018. In May 2013, FIS purchased 397,515 shares of our Series E Stock. We also granted 10 -year performance-based warrants to purchase up to 644,365 shares of Series E Stock at an exercise price of $23.64 per share. The warrants were exercisable subject to the attainment of certain milestones related to the number of active accounts for which our solutions have been enabled with accelerated vesting upon an IPO. Since FIS did not participate in the convertible promissory note financing, their warrants to purchase preferred stock were converted to warrants to purchase common stock. The warrants vested upon the completion of our IPO in February 2018, resulting in a non-cash expense of $2.5 million based on the vesting-date fair value of our common stock underlying these warrants. Since the performance conditions were directly related to revenue-producing activities, we recognized this expense in FI Share and other third-party costs on our condensed consolidated statement of operations. This expense is presented in other non-cash expenses on our condensed consolidated statement of statement of cash flows. See Note 6—Fair Value Measurements for additional information regarding the valuation of the performance-based warrants issued to FIS.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES FI Implementation Costs Agreements with certain FI partners require us to fund the development of user interface enhancements, pay for certain implementation fees, or make milestone payments upon the deployment of our solution. Amounts paid to FI partners are included in deferred FI implementation costs on our condensed consolidated balance sheets the earlier of when paid or earned and are amortized over the remaining term of the related contractual arrangements. Amortization is included in FI Share and other third-party costs on our condensed consolidated statements of operations. Certain of these agreements provide for future reductions in FI Share due to the FI partner. These reductions in FI Share are recorded as a reduction to deferred implementation costs and also result in a cumulative adjustment to accumulated amortization. Reductions to FI Share in 2018 and 2019 are expected to total $5.4 million and $4.6 million , respectively. Unearned amounts not yet paid to FI partners totaled $9.0 million as of March 31, 2018 . The following table presents changes in deferred FI implementation costs (in thousands): Three Months Ended 2017 2018 Beginning balance $ 8,451 $ 13,625 Deferred costs — 250 Recoveries through FI Share, net of accumulated amortization (963 ) (1,344 ) Amortization (391 ) (412 ) Ending balance $ 7,097 $ 12,119 During the first quarter of 2017, we incurred $1.5 million of expense related to an expected shortfall in meeting a 2017 minimum FI Share commitment recorded in FI Share and other third-party costs on our consolidated statement of operations. In the third quarter of 2017, we amended the agreement with the FI partner and removed the 2017 minimum FI Share commitment, resulting in a reversal of our accrued shortfall recorded as of June 30, 2017. We have an FI Share commitment to a certain FI partner totaling $10.0 million over a 12-month period following the completion of certain milestones, which were not met as of March 31, 2018 . Litigation From time to time, we may become involved in legal actions arising in the ordinary course of business including, but not limited to, intellectual property infringement and collection matters. We make assumptions and estimates concerning the likelihood and amount of any potential loss relating to these matters using the latest information available. We record a liability for litigation if an unfavorable outcome is probable and the amount of loss or range of loss can be reasonably estimated. If an unfavorable outcome is probable and a reasonable estimate of the loss is a range, we accrue the best estimate within the range. If no amount within the range is a better estimate than any other amount, we accrue the minimum amount within the range. If an unfavorable outcome is probable but the amount of the loss cannot be reasonably estimated, we disclose the nature of the litigation and indicates that an estimate of the loss or range of loss cannot be made. If an unfavorable outcome is reasonably possible and the estimated loss is material, we disclose the nature and estimate of the possible loss of the litigation. We do not disclose information with respect to litigation where an unfavorable outcome is considered to be remote or where the estimated loss would not be material. Based on current expectations, such matters, both individually and in the aggregate, are not expected to have a material adverse effect on our liquidity, results of operations, business or financial condition.

EARNINGS PER SHARE

EARNINGS PER SHARE	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Diluted net loss per share is the same as basic net loss per share for the three months ended March 31, 2017 and 2018 because the effects of potentially dilutive items were anti-dilutive, given our net loss during these periods. The following securities have been excluded from the calculation of diluted weighted-average common shares outstanding because the effect is anti-dilutive (in thousands): March 31, 2017 2018 Redeemable convertible preferred stock: Series A-R 1,857 — Series B-R 2,247 — Series C-R 1,508 — Series D-R 1,396 — Series E-R 795 — Series F-R 1,198 — Series G — — Series G’ — — Common stock options 2,170 2,379 Common stock warrants 1,227 927 Common stock warrants issuable pursuant to Series G Stock financing — 1,286 Redeemable convertible preferred stock warrants 110 — Restricted stock units — 1,208 Restricted securities units 47 — Convertible promissory notes 2,432 — Common stock issuable pursuant to the ESPP — 36

SEGMENTS

SEGMENTS	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
SEGMENTS	SEGMENTS We have three operating segments: our Cardlytics Direct solutions in the United States and United Kingdom and Other Platform Solutions, as determined by the information that both our Chief Executive Officer and President and Chief Operating Officer, who we consider our chief operating decision makers, use to make strategic goals and operating decisions. Our Cardlytics Direct operating segments in the United States and United Kingdom represent our proprietary native bank advertising channels and are aggregated into one reportable segment given their similar economic characteristics, nature of service, types of customers and method of distribution. Our Other Platform Solutions segment represents solutions that enable marketers and marketing service providers to leverage the power of purchase intelligence across all of their marketing investments. Revenues can be directly attributable to each segment. With the exception of non-cash equity expense and the amortization and impairment of deferred FI implementation costs, FI Share is also directly attributable to each segment. Our chief operating decision makers allocate resources to, and evaluate the performance of, our operating segments based on revenue and adjusted contribution. The accounting policies of each of our reportable segments are the same as those described in the summary of significant accounting policies. Subsequent to March 31, 2018 , we began a strategic shift to focus the majority of our efforts and resources to support the growth of Cardlytics Direct. At this time, we have not yet determined what impact this strategic change will have on our reportable segment structure. The following table provides information regarding our reportable segments (in thousands): Three Months Ended 2017 2018 Cardlytics Direct: Adjusted contribution $ 9,440 $ 14,222 Plus: FI Share and other third-party costs (1) 15,014 17,899 Revenue $ 24,454 $ 32,121 Other Platform Solutions: Adjusted contribution $ 1,155 $ 2 Plus: FI Share and other third-party costs (1) 1,272 590 Revenue $ 2,427 $ 592 Total: Adjusted contribution $ 10,595 $ 14,224 Plus: FI Share and other third-party costs (1) 16,286 18,489 Revenue $ 26,881 $ 32,713 (1) FI Share and other third party costs presented above excludes non-cash equity expense and amortization and impairment of deferred FI implementation costs, which are detailed below in our reconciliation of loss before income taxes to adjusted contribution. Adjusted Contribution Adjusted contribution represents our revenue less FI Share and other third-party costs excluding non-cash equity expense included in FI Share and amortization and impairment of deferred FI implementation costs. During the first quarter of 2018, we refined our definition of adjusted contribution used by our chief operating decision maker to exclude the impact of non-cash charges related to the issuance of equity to our FI partners and the impact of amortization and impairment of deferred FI implementation costs. We believe these changes are warranted and appropriate since these investments are expected to yield meaningful long-term relationships with our FI partners and provide incentive for our FI partners to invest in the user interfaces that complement our platform. We have recast all historical disclosures of adjusted contribution for the periods presented. The following table presents a reconciliation of loss before income taxes presented in accordance with U.S. GAAP to adjusted contribution (in thousands): Three Months Ended 2017 2018 Adjusted contribution $ 10,595 $ 14,224 Minus: Non-cash equity expense included in FI Share — 2,519 Amortization of deferred FI implementation costs 391 412 Delivery costs 1,553 1,943 Sales and marketing expense 7,232 8,216 Research and development expense 3,013 3,459 General and administration expense 4,689 6,582 Depreciation and amortization expense 765 910 Total other expense 5,415 10,238 Loss before income taxes $ (12,463 ) $ (20,055 ) The following table provides geographical information (in thousands): Three Months Ended 2017 2018 Revenue: United States $ 24,685 $ 28,987 United Kingdom 2,196 3,726 Total $ 26,881 $ 32,713 December 31, 2017 March 31, 2018 Property and equipment: United States $ 6,813 $ 6,904 United Kingdom 506 459 Total $ 7,319 $ 7,363 Capital expenditures within the United Kingdom was $0.3 million during the three months ended March 31, 2017 and less than $0.1 million during the three months ended March 31, 2018 .

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS We evaluated subsequent events for recognition and measurement purposes through May 10, 2018, the date that the condensed consolidated financial statements were issued. On May 3, 2018 and May 7, 2018, respectively, we entered into a Master Agreement and Schedule #1 to the Master Agreement (collectively, the “Agreement”) with JPMorgan Chase Bank, National Association (“Chase”), pursuant to which we have agreed to a national roll-out of Cardlytics Direct to Chase customers. Under the Agreement, we will provide Chase with access to Cardlytics Direct for an initial term beginning on the date Cardlytics Direct is made generally available to Chase’s customers and ending seven years from that date. Chase may terminate the Agreement at any time upon 90 days’ written notice. We will share billings that it generates from the sale of advertising within the Chase digital channels with Chase.

SIGNIFICANT ACCOUNTING POLICI19

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS (Policies)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Basis of Accounting	Unaudited Interim Results The accompanying unaudited interim condensed consolidated financial statements and information have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and in accordance with the rules and regulations of the Securities and Exchange Commission. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements. In the opinion of management, these financial statements contain all normal and recurring adjustments considered necessary to present fairly the financial position, results of operations, and cash flows for the periods presented. The results for interim periods presented are not necessarily indicative of the results to be expected for the full year due to the seasonality of our business which has been historically impacted by higher consumer spending during the fourth quarter. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes thereto included on our Annual Report on Form 10-K ("Annual Report") for the fiscal year ended December 31, 2017 .
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements. Significant items subject to such estimates and assumptions include revenue recognition, internal-use software development costs, income taxes, stock-based compensation, derivative instruments, income tax valuation allowance, contingencies and changes in fair value of our convertible promissory notes. We base our estimates on historical experience and also on assumptions that we believe are reasonable. Changes in facts or circumstances may cause us to change our assumptions and estimates in future periods and it is possible that actual results could differ from our current or revised future estimates.
Consumer Incentives	Consumer Incentives Our Cardlytics Direct solution is our proprietary native bank advertising channel that enables marketers to reach consumers via email and through their trusted and frequently visited online and mobile banking channels. Working with the marketer, we design a campaign that targets customers based on their purchase history. The consumer is offered an incentive to make a purchase from the marketer within a specified period. We use a portion of the fees that we collect from marketers to provide these consumer incentives to our FIs’ customers after they make qualifying purchases, which we refer to as Consumer Incentives. We report our revenue on our condensed consolidated statements of operations net of Consumer Incentives. We generally pay Consumer Incentives only with respect to our Cardlytics Direct service. We do not provide the goods or services that are purchased by our FIs’ customers from the marketers to which the Consumer Incentives relate. Accordingly, the marketer is deemed to be the principal in the relationship with the customer and, therefore, the Consumer Incentive is deemed to be a reduction in the purchase price paid by the customer for the marketer’s goods or services. While we are responsible for remitting Consumer Incentives to our FI partners for further payment to their customers, we function solely as an agent of marketers in these arrangements. Accounts receivable is recorded at the amount of gross billings to marketers, net of allowances, for the fees and Consumer Incentives that we are responsible to collect. Our accrued liabilities also include the amount of Consumer Incentives due to FI partners. As a result, accounts receivable and accrued liabilities may appear large in relation to revenue, which is reported on a net basis.
Concentration of Risk	Concentrations of Risk Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. Our cash and cash equivalents are held with two financial institutions, which we believe are of high credit quality. We believe that our accounts receivable credit risk exposure is limited as a result of being diversified among a large number of marketers segregated by both geography and industry. Historically, we have not experienced significant write-downs of our accounts receivable. One marketer represented 12% of our accounts receivable as of March 31, 2018. No other marketer represented a significant concentration of our accounts receivable as of December 31, 2017 or March 31, 2018, and no single marketer represented a significant concentration of our revenue during the three months ended March 31, 2017 or 2018. Our business is substantially dependent on a limited number of FI partners. We require participation from our FI partners in Cardlytics Direct and access to their purchase data in order to offer our solutions to marketers and their agencies. We must have FI partners with a sufficient number of customers and levels of customer engagement to ensure that we have robust purchase data and marketing space to support a broad array of incentive programs for marketers. Our agreements with a substantial majority of our FI partners have terms of three to five years but are terminable by the FI partner on 90 days or less prior notice. If an FI partner terminates its agreement with us, we would lose that FI as a source of purchase data and online banking customers.
Deferred Offering Costs	Deferred Offering Costs Deferred offering costs consist of incremental costs directly attributable to equity offerings. Deferred offering costs are included in other long-term assets on our condensed consolidated balance sheets.
Fair Value of Financial Instruments	Fair Value of Financial Instruments When required by U.S. GAAP, assets and liabilities are reported at fair value on our condensed consolidated financial statements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Valuation inputs are arranged in a hierarchy that consists of the following levels: • Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. • Level 2 inputs are inputs other than Level 1 inputs such as quoted prices for similar assets or liabilities; quoted prices in markets with insufficient volume or infrequent transactions (less active markets); or model-derived valuations in which all significant inputs are observable or can be derived principally from or corroborated by observable market data for substantially the full term of the assets or liabilities. • Level 3 inputs are unobservable inputs for the asset or liability. Our nonfinancial assets that we recognize or disclose at fair value on our condensed consolidated financial statements on a nonrecurring basis include property and equipment, intangible assets, capitalized software development costs and deferred FI implementation costs. The fair values for these assets are evaluated when events or changes in circumstances indicate the carrying value may not be recoverable.
Income Taxes	Income Taxes On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (“Tax Act”) was signed into law making significant changes to the Internal Revenue Code. Changes include, but are not limited to, a corporate tax rate decrease to 21% effective for tax years beginning after December 31, 2017. This change in tax rate resulted in a reduction in our net U.S. deferred tax assets, which was fully offset by a reduction in our valuation allowance. The other provisions of the Tax Act, including the one-time transition tax on the mandatory deemed repatriation of cumulative foreign earnings, did not have a material impact on our financial statements as of December 31, 2017. As of December 31, 2017, pursuant to guidance provided in Staff Account Bulletin No. 118, we had not completed our accounting for the effects of the Tax Act; however, we made a reasonable estimate of the effects on our existing deferred tax balances and the one-time transition tax, including a provisional reduction in U.S. deferred tax assets, which was fully offset by a reduction in our valuation allowance. As of March 31, 2018, our accounting for the Tax Act is complete. No changes have been made to the provisional adjustments recorded as of December 31, 2017.
Recently Issued and Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In May 2017, the FASB issued ASU 2017-09, Scope of Modification Accounting , which amends the scope of modification accounting for share-based payment arrangements, provides guidance on the types of changes to the terms or conditions of share-based payment awards to which an entity would be required to apply modification accounting under ASC Topic 718, Compensation—Stock Compensation . For all entities, the ASU is effective prospectively for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. We adopted this ASU on January 1, 2018 and it did not have an impact on our condensed consolidated financial statements. Recently Issued Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (Topic 606). ASU 2014-09 supersedes the recognition guidance in ASC Topic 605 and most industry specific revenue guidance and requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. In addition, this ASU requires disclosures of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. This ASU supersedes most existing GAAP revenue recognition principles, and it permits the use of either the retrospective or modified retrospective transition method. For public entities, this ASU is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods. For non-public entities, this ASU is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We have made the election to use the extended transition period for complying with new or revised accounting standards under Section 102(b)(1) of the Jumpstart Our Business Startups Act of 2012 ("JOBS Act"), therefore we will be required to apply this ASU for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Retrospective application will be required for each period presented through either the recasting of the prior periods for the effects of the adoption of this ASU or retrospectively through a cumulative catch up recognized at the date of adoption. During the first quarter of 2018, we began assessing the impacts, if any, that this ASU may have on our results of operations, current accounting policies, processes, controls, systems and financial statement disclosures. Based on our initial assessment, we expect to adopt this new standard using the modified retrospective transition method, which would result in a cumulative adjustment as of the date of the adoption. In January 2016, the FASB issued ASU 2016-01, Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which is intended to enhance the reporting model for financial instruments to provide users of financial statements with more decision-useful information. This ASU requires equity investments to be measured at fair value with changes in fair values recognized in net earnings, (public entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes), simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment and eliminates the requirement to disclose fair values, the methods and significant assumptions used to estimate the fair value of financial instruments measured at amortized cost. This ASU also clarifies that management should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale debt securities in combination with other deferred tax assets. For public business entities, this ASU is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods. For non-public business entities, this ASU is effective for fiscal years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. Early adoption is permitted. We have made the election to use the extended transition period for complying with new or revised accounting standards under Section 102(b)(1) of the JOBS Act, therefore we will be required to apply this ASU for annual reporting periods beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. We are currently evaluating the potential impact of this recently issued guidance on our condensed consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which supersedes ASC Topic 840, Leases . The ASU does not significantly change the lessees’ recognition, measurement and presentation of expenses and cash flows from the previous accounting standard. The ASU’s primary change is the requirement for lessee entities to recognize a lease liability for payments and a right of use asset representing the right to use the leased asset during the term on operating lease arrangements. Lessees are permitted to make an accounting policy election to not recognize the asset and liability for leases with a term of twelve months or less. Lessors’ accounting under the ASU is largely unchanged from the previous accounting standard. In addition, the ASU expands the disclosure requirements of lease arrangements. Lessees and lessors will use a modified retrospective transition approach. For public entities, this ASU is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. For non-public entities, this ASU is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. We have made the election to use the extended transition period for complying with new or revised accounting standards under Section 102(b)(1) of the JOBS Act, therefore we will be required to adopt this ASU for annual reporting periods beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted. Although we are currently evaluating the impact of this guidance on our condensed consolidated financial statements, we expect that most of our operating lease commitments will be recognized as operating lease liabilities and right-of-use assets upon adoption of the new guidance.

SIGNIFICANT ACCOUNTING POLICI20

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS (Tables)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Schedule of cash and cash equivalents	Cash, cash equivalents and restricted cash as presented on our condensed consolidated statements of cash flows consists of the following (in thousands): December 31, March 31, 2016 2017 2017 2018 Cash and cash equivalents $ 22,838 $ 21,262 $ 24,353 $ 89,785 Restricted cash 130 — — — Cash, cash equivalents and restricted cash $ 22,968 $ 21,262 $ 24,353 $ 89,785
Schedule of restricted cash	Cash, cash equivalents and restricted cash as presented on our condensed consolidated statements of cash flows consists of the following (in thousands): December 31, March 31, 2016 2017 2017 2018 Cash and cash equivalents $ 22,838 $ 21,262 $ 24,353 $ 89,785 Restricted cash 130 — — — Cash, cash equivalents and restricted cash $ 22,968 $ 21,262 $ 24,353 $ 89,785
Schedule of deferred costs	Three Months Ended 2017 2018 Beginning balance $ — $ 3,144 Deferred costs 776 1,135 Recognized against offering proceeds — (4,279 ) Ending balance $ 776 $ —

DEBT (Tables)

DEBT (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Schedule of long-term debt instruments	Our debt consists of the following (in thousands): December 31, 2017 March 31, 2018 Line of credit $ 25,081 $ 25,634 Term loan, net of unamortized discount and debt issuance costs of $1,058 and $889 at December 31, 2017 and March 31, 2018, respectively 31,830 32,842 Capital leases 101 75 Convertible promissory notes (converted into Series G' Stock in May 2017) — — Total debt $ 57,012 $ 58,551 Less short-term debt (44 ) (25,657 ) Long-term debt, net of current portion $ 56,968 $ 32,894
Schedule of maturities of debt and capital lease	Aggregate future payments of principal and interest due upon maturity are as follows (in thousands): Years Ending December 31, Debt Capital Leases Total Debt 2018 (remainder of year) $ — $ 18 $ 18 2019 59,365 20 59,385 2020 — 24 24 2021 — 13 13 Total principal payments $ 59,365 $ 75 $ 59,440 Less unamortized debt issuance costs (274 ) — (274 ) Less unamortized debt discount (615 ) — (615 ) Total debt $ 58,476 $ 75 $ 58,551

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Allocation of recognized period costs	The following table summarizes the allocation of stock-based compensation in the consolidated statements of operations (in thousands): Three Months Ended 2017 2018 Delivery costs $ 41 $ 85 Sales and marketing expense 344 943 Research and development expense 171 470 General and administration expense 427 1,402 Total stock-based compensation expense $ 983 $ 2,900
Summary of common stock option activity	A summary of common stock option activity is as follows (in thousands, except per share amounts): Shares Weighted-Average Exercise Price Options outstanding — December 31, 2016 2,137 $ 15.00 Granted 124 11.81 Exercised (76 ) 3.57 Forfeited (9 ) 20.59 Cancelled (6 ) 14.21 Options outstanding — March 31, 2017 2,170 $ 15.20 Shares Weighted-Average Exercise Price Options outstanding — December 31, 2017 2,514 $ 18.42 Granted 29 24.24 Exercised (26 ) 4.22 Forfeited (103 ) 25.65 Cancelled (35 ) 15.88 Options outstanding — March 31, 2018 2,379 $ 18.37
Summary of RSU activity	A summary of restricted stock unit activity is as follows (in thousands, except per share amounts): Shares Weighted-Average Grant Date Fair Value Unvested — December 31, 2017 — $ — Granted 1,210 20.80 Vested — — Forfeited (2 ) 16.80 Unvested — March 31, 2018 1,208 $ 20.81

REDEEMABLE CONVERTIBLE PREFER23

REDEEMABLE CONVERTIBLE PREFERRED STOCK (Tables)	3 Months Ended
	Mar. 31, 2018
Temporary Equity Disclosure [Abstract]
Summary of the change in carrying amount of the outstanding redeemable convertible preferred stock	A summary of the change in carrying amount of the outstanding redeemable convertible preferred stock is as follows (in thousands): Series G’ Stock Series G Stock Shares Amount Shares Amount Balance — December 31, 2017 1,295 $ 44,672 346 $ 5,110 Accretion of redeemable convertible preferred stock — — — 108 Conversion of preferred stock to common stock (1,295 ) (44,672 ) (346 ) (5,218 ) Balance — March 31, 2018 — $ — — $ — Series F-R Stock Series E-R Stock Series D-R Stock Shares Amount Shares Amount Shares Amount Balance — December 31, 2017 1,199 $ 58,449 795 $ 29,972 1,396 $ 32,728 Accretion of redeemable convertible preferred stock — 38 — 1 — 7 Conversion of preferred stock to common stock (1,199 ) (58,487 ) (795 ) (29,973 ) (1,396 ) (32,735 ) Balance — March 31, 2018 — $ — — $ — — $ — Series C-R Stock Series B-R Stock Series A-R Stock Shares Amount Shares Amount Shares Amount Balance — December 31, 2017 1,508 $ 18,366 2,247 $ 5,288 1,857 $ 1,852 Accretion of redeemable convertible preferred stock — 3 — — — — Conversion of preferred stock to common stock (1,508 ) (18,369 ) (2,247 ) (5,288 ) (1,857 ) (1,852 ) Balance — March 31, 2018 — $ — — $ — — $ —

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of financial assets and liabilities measured at fair value on a recurring basis	Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The following table summarizes our liabilities measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): December 31, 2017 Level 1 Level 2 Level 3 Total Liabilities: Preferred stock warrants $ — $ — $ 2,285 $ 2,285 Common stock warrants — — 7,945 7,945 Convertible promissory notes — — — — Total liabilities $ — $ — $ 10,230 $ 10,230 March 31, 2018 Level 1 Level 2 Level 3 Total Liabilities: Preferred stock warrants $ — $ — $ — $ — Common stock warrants — — 17,666 17,666 Convertible promissory notes — — — — Total liabilities $ — $ — $ 17,666 $ 17,666
Schedule of reconciliation of the redeemable convertible preferred stock warrant liability	Our redeemable convertible preferred stock warrants, common stock warrants issued in connection with the Series G Stock financing and our convertible promissory notes are measured and recorded at fair value on a recurring basis using Level 3 inputs. The table below provides a roll forward of the changes in fair value of Level 3 financial instruments (in thousands): Preferred Stock Warrants Common Stock Warrants Convertible Promissory Notes Balance at December 31, 2016 $ 2,197 $ — $ 72,332 Accrued interest on convertible promissory notes — — 1,246 Changes in fair value 327 — 2,606 Balance at March 31, 2017 $ 2,524 $ — $ 76,184 Preferred Stock Warrants Common Stock Warrants Convertible Promissory Notes Balance at December 31, 2017 $ 2,285 $ 7,945 $ — Changes in fair value (549 ) 9,721 — Conversion of preferred stock warrants to common stock warrants (1,736 ) — — Balance at March 31, 2018 $ — $ 17,666 $ —
Fair value inputs	The following table summarizes key assumptions used in the PWERM for estimating the fair value of our redeemable convertible preferred stock warrant liability and convertible promissory notes: March 31, 2017 Cost of debt applicable to convertible promissory notes 10% Cost of equity applicable to convertible promissory notes 22% Weighted-average cost of capital applicable to preferred stock warrants 23% Discount for lack of marketability 7% to 11% Volatility 53% Risk-free interest rate 0.7% to 1.2% We determined the fair value of these common warrants on the date of IPO using the Black-Scholes option pricing model, which is affected by the fair value of our common stock as well as the following significant inputs: Performance-based warrants (vested upon IPO) Weighted-average grant date fair value $3.91 Significant inputs: Value of common stock $13.00 Expected term 5.3 years Volatility 50% Risk-free interest rate 2.0% Dividend yield —%
Summary of our preferred stock warrants	A summary of our preferred stock warrants is as follows (in thousands, except per share amounts): Preferred Series Grant date Expiration date Exercise price December 31, 2017 March 31, 2018 Series B-R 2/26/2010 2/25/2020 $ 2.36 59 — Series D-R 9/21/2012 9/20/2022 $ 23.64 38 — Series D-R 9/21/2012 9/20/2022 $ 23.64 13 — Total 110 —

RELATED PARTIES (Tables)

RELATED PARTIES (Tables)	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Schedule of related party transactions	The following table summarizes the participation in the foregoing transactions by our directors, executive officers and holders of more than 5% of any class of our capital stock as of the date of such transactions (in thousands): Related Party Shares of Series G Preferred Stock Shares of Series G’ Preferred Stock Shares of Common Stock Warrants to Purchase Common Stock Entities affiliated with Aimia, Inc. (1) — 382 801 — Entities affiliated with Polaris Venture Partners (2) 29 212 — (6 ) Canaan VIII L.P. (3) 54 260 — (6 ) Entities affiliated with Discovery Capital (4) — 106 — — Scott D. Grimes — 26 — — Lynne M. Laube — 14 — — Entities affiliated with Mark A. Johnson (5) 35 15 — (6 ) John Klinck 6 — — (6 ) David Adams 3 — — (6 ) (1) Consists of 159,207 shares of Series G’ redeemable convertible preferred stock issued to Aeroplan Holdings Europe Sàrl, 223,020 shares of Series G’ redeemable convertible preferred stock issued to Aimia EMEA Limited and 801,329 shares of common stock issued to Aimia EMEA Limited. (2) Consists of 27,988 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners V, L.P. (“PVP V”), 205,020 shares of Series G’ redeemable convertible preferred stock issued to PVP V, 545 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners Entrepreneurs’ Fund V, L.L. (“PVP EF V”), 3,995 shares of Series G’ redeemable convertible preferred stock issued to PVP EF V, 191 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners Founders’ Fund V, L.P. (“PVP FF V”), 1,404 shares of Series G’ redeemable convertible preferred stock issued to PVP FF V, 280 shares of Series G redeemable convertible preferred stock purchased by Polaris Venture Partners Special Founders’ Fund V, L.P. (“PVP SFF V”) and 2,050 shares of Series G’ redeemable convertible preferred stock issued to PVP SFF V. Polaris Venture Management Co. V, L.L.C. is a general partner of each of PVP V, PVP EF V, PVP FF V and PVP SFF V and may be deemed to have the sole voting and dispositive power over the shares held by PVP V, PVP EF V, PVP FF V and PVP SFF V. Bryce Youngren, a member of our board of directors, is a Managing Partner of Polaris Partners and may be deemed to share voting and dispositive power over the shares held by PVP V, PVP EF V, PVP FF V and PVP SFF V. (3) John V. Balen, a member of our board of directors, is a managing member of Canaan Partners VIII LLC, the general partner of Canaan VIII L.P. Mr. Balen does not have voting or investment power over any shares held directly by Canaan VIII L.P. (4) Consists of 95,272 shares of Series G’ redeemable convertible preferred stock issued to Discovery Opportunity Master Fund, Ltd. and 11,072 shares of Series G’ redeemable convertible preferred stock issued to Discovery Global Focus Master Fund, Ltd. (5) Consists of 15,045 shares of Series G’ redeemable convertible preferred stock issued to TTP Fund II, L.P., 29,005 shares of Series G redeemable convertible preferred stock purchased by TTV Ivy Holdings, LLC and 5,801 shares of Series G redeemable convertible preferred stock purchased by Mr. Johnson. TTV Capital is a provider of management services to TTP GP II, LLC, which is a general partner of TTP Fund II, L.P. TTV Capital is the manager of TTV Ivy Holdings Manager, LLC, which is the general partner of TTV Ivy Holdings, LLC. Mark A. Johnson, a member of our board of directors, is a member of each of TTP GP II, LLC and TTV Ivy Holdings Managers, LLC and holds the title of partner of TTV Capital, and may be deemed to share voting and dispositive power over the shares held by TTP Fund II L.P. and TTV Ivy Holdings, LLC. (6) The maximum number of shares issuable to each investor upon the exercise of such warrants is equal to the number of shares of Series G redeemable convertible preferred stock set forth opposite such investor’s name in the table above. The actual number of shares issuable to each investor upon the exercise of such warrants is equal to the product obtained by multiplying the number of shares of Series G redeemable convertible preferred stock set forth opposite such investor’s name in the table above by a fraction, the numerator of which is the difference between $68.9516 and the volume weighted average closing price of our common stock over the 30 trading days (or such lesser number of days as our common stock has been traded on the Nasdaq Global Market) prior to the date on which such warrants become exercisable and the denominator of which is such volume weighted average closing price.

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Deferred FI implementation costs	The following table presents changes in deferred FI implementation costs (in thousands): Three Months Ended 2017 2018 Beginning balance $ 8,451 $ 13,625 Deferred costs — 250 Recoveries through FI Share, net of accumulated amortization (963 ) (1,344 ) Amortization (391 ) (412 ) Ending balance $ 7,097 $ 12,119

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of antidilutive securities	The following securities have been excluded from the calculation of diluted weighted-average common shares outstanding because the effect is anti-dilutive (in thousands): March 31, 2017 2018 Redeemable convertible preferred stock: Series A-R 1,857 — Series B-R 2,247 — Series C-R 1,508 — Series D-R 1,396 — Series E-R 795 — Series F-R 1,198 — Series G — — Series G’ — — Common stock options 2,170 2,379 Common stock warrants 1,227 927 Common stock warrants issuable pursuant to Series G Stock financing — 1,286 Redeemable convertible preferred stock warrants 110 — Restricted stock units — 1,208 Restricted securities units 47 — Convertible promissory notes 2,432 — Common stock issuable pursuant to the ESPP — 36

SEGMENTS (Tables)

SEGMENTS (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Schedule of segment reporting information	The following table provides information regarding our reportable segments (in thousands): Three Months Ended 2017 2018 Cardlytics Direct: Adjusted contribution $ 9,440 $ 14,222 Plus: FI Share and other third-party costs (1) 15,014 17,899 Revenue $ 24,454 $ 32,121 Other Platform Solutions: Adjusted contribution $ 1,155 $ 2 Plus: FI Share and other third-party costs (1) 1,272 590 Revenue $ 2,427 $ 592 Total: Adjusted contribution $ 10,595 $ 14,224 Plus: FI Share and other third-party costs (1) 16,286 18,489 Revenue $ 26,881 $ 32,713 (1) FI Share and other third party costs presented above excludes non-cash equity expense and amortization and impairment of deferred FI implementation costs, which are detailed below in our reconciliation of loss before income taxes to adjusted contribution. The following table presents a reconciliation of loss before income taxes presented in accordance with U.S. GAAP to adjusted contribution (in thousands): Three Months Ended 2017 2018 Adjusted contribution $ 10,595 $ 14,224 Minus: Non-cash equity expense included in FI Share — 2,519 Amortization of deferred FI implementation costs 391 412 Delivery costs 1,553 1,943 Sales and marketing expense 7,232 8,216 Research and development expense 3,013 3,459 General and administration expense 4,689 6,582 Depreciation and amortization expense 765 910 Total other expense 5,415 10,238 Loss before income taxes $ (12,463 ) $ (20,055 )
Schedule of revenue by geographic areas	The following table provides geographical information (in thousands): Three Months Ended 2017 2018 Revenue: United States $ 24,685 $ 28,987 United Kingdom 2,196 3,726 Total $ 26,881 $ 32,713 December 31, 2017 March 31, 2018 Property and equipment: United States $ 6,813 $ 6,904 United Kingdom 506 459 Total $ 7,319 $ 7,363

OVERVIEW OF BUSINESS AND BASI29

OVERVIEW OF BUSINESS AND BASIS OF PRESENTATION (Details)	Feb. 14, 2018USD ($)shares	Feb. 14, 2018USD ($)shares	Feb. 13, 2018USD ($)$ / sharesshares	Jan. 26, 2018USD ($)$ / sharesshares	Mar. 31, 2018USD ($)$ / sharesshares	Mar. 31, 2017USD ($)	Dec. 31, 2017$ / sharesshares	May 31, 2017shares	Feb. 28, 2017shares
Debt Instrument [Line Items]
Sale of stock, number of shares issued in transaction (in shares) | shares	421,355	5,821,355
Proceeds from IPO	$ 5,500,000	$ 75,700,000
Proceeds from IPO, net		66,100,000
Sale of stock, discounts and commissions		5,300,000
Issuance costs		$ 4,300,000			$ 4,279,000	$ 0
Stock split, conversion ratio					0.25
Proceeds from issuance of common stock, threshold				$ 70,000,000
Shares authorized (in shares) | shares				100,000,000	100,000,000		83,000,000	83,000,000
Par value (in usd per share) | $ / shares				$ 0.0001	$ 0.0001		$ 0.0001
Shares authorized (in shares) | shares				25,000,000				96,131,002	82,683,212
Redeemable convertible preferred stock, par value (in usd per share) | $ / shares				$ 0.0001
IPO
Debt Instrument [Line Items]
Sale of stock, number of shares issued in transaction (in shares) | shares			5,400,000
Sale of stock, price per share (in usd per share) | $ / shares			$ 13
Proceeds from IPO			$ 70,200,000
Over-Allotment Option
Debt Instrument [Line Items]
Sale of stock, number of shares issued in transaction (in shares) | shares	810,000

SIGNIFICANT ACCOUNTING POLICI30

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS - Consumer Incentives (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Accounting Policies [Abstract]
Consumer incentives, expense	$ 16	$ 13.2

SIGNIFICANT ACCOUNTING POLICI31

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS - Concentrations of Risk (Details)	Mar. 31, 2018	Mar. 31, 2018	Mar. 31, 2017
Concentration Risk [Line Items]
Financial institutions agreement, notice period		90 days
Minimum
Concentration Risk [Line Items]
Financial institutions agreement, term		3 years
Maximum
Concentration Risk [Line Items]
Financial institutions agreement, term		5 years
One Customer | Customer Concentration Risk | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk	12.00%
Largest FI Partner | Supplier Concentration Risk | Financial Institution Partner
Concentration Risk [Line Items]
Concentration risk		69.00%	69.00%

SIGNIFICANT ACCOUNTING POLICI32

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS - Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Cash and cash equivalents	$ 89,785	$ 21,262	$ 24,353	$ 22,838
Restricted cash	0	0	0	130
Cash, cash equivalents and restricted cash	$ 89,785	$ 21,262	$ 24,353	$ 22,968

SIGNIFICANT ACCOUNTING POLICI33

SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING STANDARDS - Deferred Offering Costs (Details) - USD ($) $ in Thousands	Feb. 14, 2018	Mar. 31, 2018	Mar. 31, 2017
Deferred Financial Institution Costs [Roll Forward]
Deferred offering costs		$ 3,144	$ 0
Deferred costs incurred during period		1,135	776
Issuance costs	$ (4,300)	(4,279)	0
Deferred offering costs		0	$ 776
Deferred offering costs, unpaid		$ 700

DEBT - Schedule of Debt (Detail

DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total debt	$ 58,551	$ 57,012
Less short-term debt	(25,657)	(44)
Long-term debt, net of current portion	32,894	56,968
Line of credit
Debt Instrument [Line Items]
Total debt	25,634	25,081
Term loans
Debt Instrument [Line Items]
Total debt	32,842	31,830
Unamortized discount (premium) and debt issuance costs	889	1,058
Capital leases
Debt Instrument [Line Items]
Total debt	75	101
Convertible Promissory Notes
Debt Instrument [Line Items]
Total debt	$ 0	$ 0

DEBT - Narrative (Details)

DEBT - Narrative (Details) - USD ($)	1 Months Ended					3 Months Ended
	Jun. 30, 2017	Apr. 30, 2017	Nov. 30, 2016	Jul. 31, 2016	May 31, 2013	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Sep. 30, 2016
Debt Instrument [Line Items]
Accrued interest						$ 7,600,000		$ 6,200,000
Long-term debt						58,476,000
Proceeds from issuance of debt						0	$ 7,500,000
Warrant, term	10 years			10 years	10 years
Number of securities issued by warrants (in shares)	17,500			97,125
Exercise price of warrants (in usd per share)	$ 27.68			$ 20	$ 23.64
Fair value of warrants	$ 300,000			$ 1,000,000
Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 50,000,000
Maximum borrowing capacity, percentage of accounts receivable						85.00%
Interest rate (not to be less than)						7.00%
Commitment fee percentage						0.50%
Annual administrative fee						$ 100,000
Debt issuance costs									$ 700,000
Line of credit facility, covenant, minimum cash balance						5,000,000
Line of credit facility, covenant, minimum 12 month revenue						123,300,000
Line of credit facility, remaining borrowing capacity						$ 4,900,000
Line of credit | Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate						3.50%
Term loans
Debt Instrument [Line Items]
Debt instrument, face amount				24,000,000
Proceeds from issuance of debt	$ 5,000,000		$ 5,000,000	$ 19,000,000
Revenue threshold, trailing four quarter revenue			$ 100,000,000
Interest rate, rate reduction		0.50%
Term loan, covenant, line of credit availability threshold (not less than)						$ 3,000,000
Term loan, Covenant, Adjusted EBITDA, Two consecutive quarters (at least)						$ 1,000,000
Fixed Interest Rate | Term loans
Debt Instrument [Line Items]
Interest rate (not to be less than)						13.25%
Interest rate, percentage, payable in cash						3.00%
Interest rate, percentage, payable in kind						10.25%
IPO gross proceeds $75.0 million | Term loans
Debt Instrument [Line Items]
Interest rate (not to be less than)						12.75%
Interest rate, percentage, payable in cash						3.00%
Proceeds from issuance of common stock, threshold amount (at least)						$ 75,000,000
Interest rate, percentage, payable in kind						9.75%
EBITDA Thresholds Met | Term loans
Debt Instrument [Line Items]
Interest rate, percentage, payable in cash						3.00%
Adjusted EBITDA threshold (greater than)						$ 1,000,000
EBITDA Thresholds Met | Term loans | Minimum
Debt Instrument [Line Items]
Interest rate (not to be less than)						11.25%
Interest rate, percentage, payable in kind						8.25%
Convertible Promissory Notes
Debt Instrument [Line Items]
Accrued interest on convertible promissory notes							$ 1,246,000
Convertible Promissory Notes | Convertible Promissory Notes
Debt Instrument [Line Items]
Debt instrument, face amount						$ 50,700,000

DEBT - Future Payments (Details

DEBT - Future Payments (Details) $ in Thousands	Mar. 31, 2018USD ($)
Debt
2018 (remainder of year)	$ 0
2,019	59,365
2,020	0
2,021	0
Total principal payments	59,365
Less unamortized debt issuance costs	(274)
Less unamortized debt discount	(615)
Total debt	58,476
Capital Leases
2018 (remainder of year)	18
2,019	20
2,020	24
2,021	13
Total principal payments	75
Total Debt
2018 (remainder of year)	18
2,019	59,385
2,020	24
2,021	13
Total principal payments	59,440
Less unamortized debt issuance costs	(274)
Less unamortized debt discount	(615)
Total debt	$ 58,551

STOCK-BASED COMPENSATION - Narr

STOCK-BASED COMPENSATION - Narrative (Details) $ / shares in Units, user in Millions, $ in Millions	1 Months Ended		3 Months Ended			12 Months Ended
	Feb. 28, 2018USD ($)	May 31, 2013$ / shares	Jun. 30, 2018USD ($)shares	Mar. 31, 2018USD ($)trancheuser$ / sharesshares	Mar. 31, 2017USD ($)$ / shares	Dec. 31, 2016shares	Feb. 08, 2018shares	Jan. 31, 2018shares	May 31, 2017shares	May 30, 2017shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)							1,875,000
Number of shares remaining available for issuance (in shares)							61,247
Number of shares authorized, annual increase				5.00%
Weighted-average grant date fair value (in usd per share) | $ / shares		$ 3.91		$ 10	$ 7.32
Options vested in period, fair value | $				$ 1.2	$ 0.6
Award vesting period				4 years
Expiration period				10 years
Compensation not yet recognized | $				$ 10.4
Common stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized				2 years 8 months 12 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				1,210,000
Number of tranches | tranche				2
RSU issued (in shares)				437,500
Compensation not yet recognized, awards other than options | $				$ 24.3
Compensation cost not yet recognized				4 years 3 months 18 days
Restricted stock units | Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU, performance condition | user				70
RSU, performance condition, period				3 years
Restricted stock units | Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU, performance condition | user				85
RSU, performance condition, period				5 years
Restricted securities units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU issued (in shares)						1,000,000
RSU, service condition period				6 months
Award period for sale of company or IPO				5 years
Stock option expense | $	$ 0.5
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				375,000
ESPP, purchase price percentage				85.00%
ESPP, number of shares authorized, annual percentage increase				1.00%
ESPP, number of shares authorized, annual increase (in shares)				500,000
2008 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)								4,020,000	3,495,000	3,120,000
Employees and non-employee directors | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				335,562
Employees and non-employee directors | Minimum | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				1 year
Employees and non-employee directors | Maximum | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				4 years
Forecast | Subsequent Event | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
Granted (in shares)			32,070
Compensation not yet recognized, awards other than options | $			$ 0.5

STOCK-BASED COMPENSATION - Allo

STOCK-BASED COMPENSATION - Allocation of Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 983	$ 2,900
Delivery costs
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	41	85
Sales and marketing expense
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	344	943
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	171	470
General and administration expense
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 427	$ 1,402

STOCK-BASED COMPENSATION - Summ

STOCK-BASED COMPENSATION - Summary of Common Stock Option Activity (Details) - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Shares
Beginning balance (in shares)	2,514	2,137
Granted (in shares)	29	124
Exercised (in shares)	(26)	(76)
Forfeited (in shares)	(103)	(9)
Canceled (in shares)	(35)	(6)
Ending balance (in shares)	2,379	2,170
Weighted-Average Exercise Price
Beginning balance (in usd per share)	$ 18.42	$ 15
Granted (in usd per share)	24.24	11.81
Exercised (in usd per share)	4.22	3.57
Forfeited (in usd per share)	25.65	20.59
Canceled (in usd per share)	15.88	14.21
Ending balance (in usd per share)	$ 18.37	$ 15.20

STOCK-BASED COMPENSATION - Su40

STOCK-BASED COMPENSATION - Summary of RSU Activity (Details) - Restricted stock units shares in Thousands	3 Months Ended
	Mar. 31, 2018$ / sharesshares
Shares
Unvested — Beginning balance (in shares) | shares	0
Granted (in shares) | shares	1,210
Vested (in shares) | shares	0
Forfeited (in shares) | shares	(2)
Unvested — Ending balance (in shares) | shares	1,208
Weighted-Average Grant Date Fair Value
Unvested — Beginning balance (in usd per share) | $ / shares	$ 0
Granted (in usd per share) | $ / shares	20.80
Vested (in usd per share) | $ / shares	0
Forfeited (in usd per share) | $ / shares	16.80
Unvested — Ending balance (in usd per share) | $ / shares	$ 20.81

REDEEMABLE CONVERTIBLE PREFER41

REDEEMABLE CONVERTIBLE PREFERRED STOCK - Outstanding Stock (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)shares
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 196,437
Conversion of preferred stock to common stock	(196,594)
Ending balance	$ 0
Series G’ Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	1,295,000
Beginning balance	$ 44,672
Accretion of redeemable convertible preferred stock	$ 0
Conversion of preferred stock to common stock (in shares) | shares	(1,295,000)
Conversion of preferred stock to common stock	$ (44,672)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series G Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	346,000
Beginning balance	$ 5,110
Accretion of redeemable convertible preferred stock	$ 108
Conversion of preferred stock to common stock (in shares) | shares	(346,000)
Conversion of preferred stock to common stock	$ (5,218)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series F-R Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	1,199,000
Beginning balance	$ 58,449
Accretion of redeemable convertible preferred stock	$ 38
Conversion of preferred stock to common stock (in shares) | shares	(1,199,000)
Conversion of preferred stock to common stock	$ (58,487)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series E-R Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	795,000
Beginning balance	$ 29,972
Accretion of redeemable convertible preferred stock	$ 1
Conversion of preferred stock to common stock (in shares) | shares	(795,000)
Conversion of preferred stock to common stock	$ (29,973)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series D-R Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	1,396,000
Beginning balance	$ 32,728
Accretion of redeemable convertible preferred stock	$ 7
Conversion of preferred stock to common stock (in shares) | shares	(1,396,000)
Conversion of preferred stock to common stock	$ (32,735)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series C-R Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	1,508,000
Beginning balance	$ 18,366
Accretion of redeemable convertible preferred stock	$ 3
Conversion of preferred stock to common stock (in shares) | shares	(1,508,000)
Conversion of preferred stock to common stock	$ (18,369)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series B-R Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	2,247,000
Beginning balance	$ 5,288
Accretion of redeemable convertible preferred stock	$ 0
Conversion of preferred stock to common stock (in shares) | shares	(2,247,000)
Conversion of preferred stock to common stock	$ (5,288)
Ending balance (in shares) | shares	0
Ending balance	$ 0
Series A-R Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance (in shares) | shares	1,857,000
Beginning balance	$ 1,852
Accretion of redeemable convertible preferred stock	$ 0
Conversion of preferred stock to common stock (in shares) | shares	(1,857,000)
Conversion of preferred stock to common stock	$ (1,852)
Ending balance (in shares) | shares	0
Ending balance	$ 0

REDEEMABLE CONVERTIBLE PREFER42

REDEEMABLE CONVERTIBLE PREFERRED STOCK - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	May 31, 2017	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017	Jan. 26, 2018	Dec. 31, 2017	Feb. 28, 2017	Jul. 31, 2016	May 31, 2013
Temporary Equity [Line Items]
Shares authorized (in shares)	96,131,002				25,000,000		82,683,212
Shares authorized (in shares)	83,000,000	100,000,000			100,000,000	83,000,000
Redeemable convertible preferred stock, par value (in usd per share)					$ 0.0001
Issuance costs		$ 1,232		$ 181
Conversion of stock, shares converted (in shares)	801,329
Shares issued (in shares)		20,226,000				3,439,000
Class of warrant, numerator input value (in usd per share)	$ 68.9516
Number of trading days	30 days
Exercise price of warrants (in usd per share)			$ 27.68					$ 20	$ 23.64
Series G Stock
Temporary Equity [Line Items]
Shares authorized (in shares)		0				1,385,000
Issuance of Series G and Series G’ Stock	$ 11,900
Issuance of Series G and Series G’ Stock (in shares)	346,334
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001				$ 0.0001
Shares issued (in usd per share)	$ 34.4758
Issuance costs	$ 100
Shares issued (in shares)	346,334
Class of warrant, numerator input value (in usd per share)	$ 68.9516
Number of trading days	30 days
Number of days following prospectus	180 days
Number of days prior to sale of company	10 days
Exercise price of warrants (in usd per share)	$ 0.0004
Proceeds from issuance of Series G preferred stock	$ 11,900
Redeemable convertible preferred stock, residual value	4,500
Deemed dividend related to beneficial conversion feature	$ 6,100
Deemed dividend related to beneficial conversion feature			$ 4,500
Series G’ Stock
Temporary Equity [Line Items]
Shares authorized (in shares)		0				5,339,000
Redeemable convertible preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001				$ 0.0001
Shares issued (in usd per share)	$ 2.758
Conversion of stock, shares converted (in shares)	1,295,746
Additional Paid-In Capital | Series G Stock
Temporary Equity [Line Items]
Beneficial conversion feature of Series G stock	$ 4,500

FAIR VALUE MEASUREMENTS - Narra

FAIR VALUE MEASUREMENTS - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended					3 Months Ended
	Feb. 28, 2018	Jun. 30, 2017	May 31, 2017	Jul. 31, 2016	May 31, 2013	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shares issued (in shares)						20,226,000		3,439,000
Class of warrant, numerator input value (in usd per share)			$ 68.9516
Number of trading days			30 days
Class of warrant (in shares)					644,365	0		110,000
Exercise price of warrants (in usd per share)		$ 27.68		$ 20	$ 23.64
Volatility					50.00%		53.00%
Warrant, term		10 years		10 years	10 years
Common Stock Warrants
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability value						$ 17,666	$ 0	$ 7,945	$ 0
Changes in fair value, loss						9,721	0
Accrued interest on convertible promissory notes							0
Convertible promissory notes (converted into Series G' Stock in May 2017)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability value						0	76,184	$ 0	$ 72,332
Changes in fair value, loss						$ 0	2,606
Accrued interest on convertible promissory notes							$ 1,246
Series G Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shares issued (in shares)			346,334
Class of warrant, numerator input value (in usd per share)			$ 68.9516
Number of trading days			30 days
Number of days following prospectus			180 days
Number of days prior to sale of company			10 days
Exercise price of warrants (in usd per share)			$ 0.0004
Volatility			59.00%
Discount for lack of marketability			11.00%
Liability value			$ 7,500
Series B-R Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value per share (in usd per share)						$ 20.18		$ 26.8
Series D-R Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value per share (in usd per share)						$ 10.57		$ 13.63
Common Stock Warrants
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stock option expense	$ 2,500

FAIR VALUE MEASUREMENTS - Finan

FAIR VALUE MEASUREMENTS - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	$ 0	$ 10,230
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Common stock warrants	0	0
Total liabilities	17,666	10,230
Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Common stock warrants	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Common stock warrants	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Common stock warrants	0	0
Total liabilities	17,666	10,230
Preferred Stock Warrants | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	0	2,285
Preferred Stock Warrants | Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	0	0
Preferred Stock Warrants | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	0	0
Preferred Stock Warrants | Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	0	2,285
Common Stock Warrants | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	17,666	7,945
Common Stock Warrants | Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	0	0
Common Stock Warrants | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	0	0
Common Stock Warrants | Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term warrant liability	$ 17,666	$ 7,945

FAIR VALUE MEASUREMENTS - Instr

FAIR VALUE MEASUREMENTS - Instruments Recorded at Fair Value Using Level 3 Inputs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Preferred Stock Warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 2,285	$ 2,197
Accrued interest on convertible promissory notes		0
Changes in fair value	(549)	327
Conversion of preferred stock warrants to common stock warrants	(1,736)
Fair value, ending balance	0	2,524
Common Stock Warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	7,945	0
Accrued interest on convertible promissory notes		0
Changes in fair value	9,721	0
Conversion of preferred stock warrants to common stock warrants	0
Fair value, ending balance	17,666	0
Convertible Promissory Notes
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	0	72,332
Accrued interest on convertible promissory notes		1,246
Changes in fair value	0	2,606
Conversion of preferred stock warrants to common stock warrants	0
Fair value, ending balance	$ 0	$ 76,184

FAIR VALUE MEASUREMENTS - Fair

FAIR VALUE MEASUREMENTS - Fair Value Assumptions (Details)	1 Months Ended	3 Months Ended
	May 31, 2013	Mar. 31, 2018	Mar. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost of debt applicable to convertible promissory notes			10.00%
Cost of equity applicable to convertible promissory notes			22.00%
Weighted-average cost of capital applicable to preferred stock warrants			23.00%
Volatility	50.00%		53.00%
Risk-free interest rate	2.00%
Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount for lack of marketability		7.00%	7.00%
Risk-free interest rate		1.20%	0.70%
Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount for lack of marketability		13.00%	11.00%
Risk-free interest rate		1.40%	1.20%

FAIR VALUE MEASUREMENTS - Prefe

FAIR VALUE MEASUREMENTS - Preferred Stock Warrants (Details) - $ / shares	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Jul. 31, 2016	May 31, 2013
Class of Stock [Line Items]
Exercise price of warrants (in usd per share)			$ 27.68	$ 20	$ 23.64
Class of warrant (in shares)	0	110,000			644,365
Series B-R Stock | Grant One
Class of Stock [Line Items]
Exercise price of warrants (in usd per share)	$ 2.36
Class of warrant (in shares)	0	59,000
Series D-R Stock | Grant One
Class of Stock [Line Items]
Exercise price of warrants (in usd per share)	$ 23.64
Class of warrant (in shares)	0	38,000
Series D-R Stock | Grant Two
Class of Stock [Line Items]
Exercise price of warrants (in usd per share)	$ 23.64
Class of warrant (in shares)	0	13,000

FAIR VALUE MEASUREMENTS - Perfo

FAIR VALUE MEASUREMENTS - Performance-based Warrants (Details) - $ / shares	1 Months Ended	3 Months Ended
	May 31, 2013	Mar. 31, 2018	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Weighted-average grant date fair value (in usd per share)	$ 3.91	$ 10	$ 7.32
Significant inputs:
Value of common stock (in usd per share)	$ 13
Expected term	5 years 3 months 18 days
Volatility	50.00%		53.00%
Risk-free interest rate	2.00%
Dividend yield	0.00%

RELATED PARTIES - Narrative (De

RELATED PARTIES - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended					3 Months Ended
	Feb. 28, 2018	Jun. 30, 2017	May 31, 2017	Jul. 31, 2016	May 31, 2013	Mar. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Conversion of stock, shares converted (in shares)			801,329
Warrant, term		10 years		10 years	10 years
Class of warrant (in shares)					644,365	0	110,000
Exercise price of warrants (in usd per share)		$ 27.68		$ 20	$ 23.64
Series G Stock
Related Party Transaction [Line Items]
Proceeds from issuance of Series G preferred stock			$ 11.9
Issuance of Series G and Series G’ Stock (in shares)			346,334
Exercise price of warrants (in usd per share)			$ 0.0004
Series G’ Stock
Related Party Transaction [Line Items]
Conversion of stock, shares converted (in shares)			1,295,746
Series E
Related Party Transaction [Line Items]
Issuance of Series G and Series G’ Stock (in shares)					397,515
Common Stock Warrants
Related Party Transaction [Line Items]
Stock option expense	$ 2.5
Stockholders' Equity | Shareholder Concentration Risk
Related Party Transaction [Line Items]
Concentration risk						5.00%

RELATED PARTIES - Series G _ Se

RELATED PARTIES - Series G / Series G’ (Details) - $ / shares	1 Months Ended
	May 31, 2017	Mar. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Shares outstanding (in shares)		20,226,000	3,439,000
Class of warrant, numerator input value (in usd per share)	$ 68.9516
Number of trading days	30 days
Series G Stock
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0	346,000
Class of warrant, numerator input value (in usd per share)	$ 68.9516
Number of trading days	30 days
Series G’ Stock
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0	1,295,000
Aimia Inc. | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		801,000
Aimia Inc. | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Aimia Inc. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		382,000
Polaris Venture Partners | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Polaris Venture Partners | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		29,000
Polaris Venture Partners | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		212,000
Canaan VIII L.P. | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Canaan VIII L.P. | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		54,000
Canaan VIII L.P. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		260,000
Discovery Capital | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Discovery Capital | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Discovery Capital | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		106,000
Scott D. Grimes | Scott D. Grimes
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Scott D. Grimes | Series G Stock | Scott D. Grimes
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Scott D. Grimes | Series G’ Stock | Scott D. Grimes
Related Party Transaction [Line Items]
Shares outstanding (in shares)		26,000
Lynne M. Laube | Lynne M. Laube
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Lynne M. Laube | Series G Stock | Lynne M. Laube
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Lynne M. Laube | Series G’ Stock | Lynne M. Laube
Related Party Transaction [Line Items]
Shares outstanding (in shares)		14,000
Entities affiliated with Mark A. Johnson | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Entities affiliated with Mark A. Johnson | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		35,000
Entities affiliated with Mark A. Johnson | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		15,000
Mark A. Johnson | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		5,801
John Klinck | Director
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
John Klinck | Series G Stock | Director
Related Party Transaction [Line Items]
Shares outstanding (in shares)		6,000
John Klinck | Series G’ Stock | Director
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
David Adams | Director
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
David Adams | Series G Stock | Director
Related Party Transaction [Line Items]
Shares outstanding (in shares)		3,000
David Adams | Series G’ Stock | Director
Related Party Transaction [Line Items]
Shares outstanding (in shares)		0
Aeroplan Holdings Europe Sàrl | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		159,207
Aimia EMEA Limited | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		801,329
Aimia EMEA Limited | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		223,020
Polaris Venture Partners V, L.P. | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		27,988
Polaris Venture Partners V, L.P. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		205,020
Polaris Venture Partners Entrepreneurs’ Fund V, L.L. | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		545
Polaris Venture Partners Entrepreneurs’ Fund V, L.L. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		3,995
Polaris Venture Partners Founders’ Fund V, L.P. | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		191
Polaris Venture Partners Founders’ Fund V, L.P. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		1,404
Polaris Venture Partners Special Founders’ Fund V, L.P. | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		280
Polaris Venture Partners Special Founders’ Fund V, L.P. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		2,050
Discovery Opportunity Master Fund, Ltd. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		95,272
Discovery Global Opportunity Master Fund, Ltd. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		11,072
TTP Fund II, L.P. | Series G’ Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		15,045
TTV Ivy Holdings, LLC | Series G Stock | Affiliated Entity
Related Party Transaction [Line Items]
Shares outstanding (in shares)		29,005

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2018
Loss Contingencies [Line Items]
Reductions to FI share, 2018		$ 5.4
Reductions to FI share, 2019		4.6
Amounts not yet paid to FI		9
FI share, expense	$ 1.5
Financial Institution Share Commitment
Loss Contingencies [Line Items]
FI share commitment		$ 10

COMMITMENTS AND CONTINGENCIES52

COMMITMENTS AND CONTINGENCIES - Deferred FI Implementation Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Deferred Financial Institution Costs [Roll Forward]
Beginning balance	$ 13,625	$ 8,451
Deferred costs	250	0
Recoveries through FI Share, net of accumulated amortization	(1,344)	(963)
Amortization	(412)	(391)
Ending balance	$ 12,119	$ 7,097

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Redeemable convertible preferred stock | Series A-R Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	1,857
Redeemable convertible preferred stock | Series B-R Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	2,247
Redeemable convertible preferred stock | Series C-R Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	1,508
Redeemable convertible preferred stock | Series D-R Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	1,396
Redeemable convertible preferred stock | Series E-R Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	795
Redeemable convertible preferred stock | Series F-R Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	1,198
Redeemable convertible preferred stock | Series G Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	0
Redeemable convertible preferred stock | Series G’ Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	0
Common stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	2,379	2,170
Common Stock Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	927	1,227
Common Stock Warrants | Series G’ Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	1,286	0
Redeemable convertible preferred stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	110
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	1,208	0
Restricted securities units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	47
Convertible promissory notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0	2,432
Common stock issuable pursuant to the ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	36	0

SEGMENTS - Narrative (Details)

SEGMENTS - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)segment	Mar. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment	3
Capital expenditures	$ 418	$ 386
United Kingdom
Segment Reporting Information [Line Items]
Capital expenditures	$ 100	$ 300

SEGMENTS - Revenue by Segment (

SEGMENTS - Revenue by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Adjusted contribution	$ 14,224	$ 10,595
Plus: FI Share and other third-party costs	18,489	16,286
Revenues	32,713	26,881
Cardlytics Direct
Segment Reporting Information [Line Items]
Adjusted contribution	14,222	9,440
Plus: FI Share and other third-party costs	17,899	15,014
Revenues	32,121	24,454
Other Platform Solutions
Segment Reporting Information [Line Items]
Adjusted contribution	2	1,155
Plus: FI Share and other third-party costs	590	1,272
Revenues	$ 592	$ 2,427

SEGMENTS - Adjusted Contributio

SEGMENTS - Adjusted Contribution Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting [Abstract]
Adjusted contribution	$ 14,224	$ 10,595
Non-cash equity expense included in FI Share	2,519	0
Amortization of deferred FI implementation costs	412	391
Delivery costs	1,943	1,553
Sales and marketing expense	8,216	7,232
Research and development expense	3,459	3,013
General and administration expense	6,582	4,689
Depreciation and amortization expense	910	765
Total other expense	10,238	5,415
LOSS BEFORE INCOME TAXES	$ (20,055)	$ (12,463)

SEGMENTS - Geographical Informa

SEGMENTS - Geographical Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ 32,713	$ 26,881
Property and equipment	7,363		$ 7,319
United States
Segment Reporting Information [Line Items]
Revenues	28,987	24,685
Property and equipment	6,904		6,813
United Kingdom
Segment Reporting Information [Line Items]
Revenues	3,726	$ 2,196
Property and equipment	$ 459		$ 506

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - Chase - Subsequent Event	May 10, 2018
Subsequent Event [Line Items]
Master agreement, term	7 years
Master agreement, cancellation period	90 days