Amendment No. 2
to
FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

42 N. Chestnut Street
Ventura, California 93001
(805) 585-3434
(Address, including zip code, and telephone number, including
area code, of Registrant's principal executive offices)

Jeff T. Green
Chief Executive Officer
The Trade Desk, Inc.
42 N. Chestnut Street
Ventura, California 93001
(805) 585-3434
(Name, address, including zip code, and telephone number,
including area code, of agent for service)

Approximate date of commencement of proposed sale to the public:
As soon as practicable after this registration statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act, check the following box: o

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this preliminary prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

This is the initial public offering of our Class A common stock. We are selling 4,666,667 shares of our Class A common stock. We and the selling stockholders named in this prospectus are selling up to 700,000 shares of Class A common stock if and to the extent that the underwriters exercise their option to purchase additional shares described below. We will not receive any proceeds from the sale of any shares of Class A common stock by the selling stockholders. We currently expect the initial public offering price to be between $16.00 and $18.00 per share of Class A common stock.

We have two classes of authorized common stock, Class A common stock and Class B common stock. The rights of the holders of Class A common stock and Class B common stock are identical, except for voting and conversion rights. Each share of Class A common stock is entitled to one vote. Each share of Class B common stock is entitled to ten votes and is convertible at any time into one share of Class A common stock. Following this offering, outstanding shares of Class B common stock will represent approximately 99% of the voting power of our outstanding capital stock, and outstanding shares of common stock held by our executive officers, directors and holders of more than 5% of our capital stock will represent approximately 85% of the voting power of our outstanding capital stock, assuming in each case no exercise by the underwriters of their option to purchase additional shares.

We have applied to list our Class A common stock on The NASDAQ Global Market under the symbol "TTD".

We are an "emerging growth company" as defined under federal securities laws and, as such, have elected to comply with certain reduced public company reporting requirements.

Investing in our Class A common stock involves risks. See "Risk Factors" beginning on page 13.

Neither the Securities and Exchange Commission nor any other regulatory body has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

We and the selling stockholders have granted the underwriters the option to purchase up to an additional 700,000 shares of Class A common stock at the initial public offering price, less the underwriting discount.

The underwriters expect to deliver the shares to purchasers on or about , 2016 through the book-entry facilities of The Depository Trust Company.

We have not authorized anyone to provide you with different information, and we take no responsibility for any other information others may give you. We are not, and the underwriters are not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained in this prospectus is accurate as of any date other than its date.

SUMMARY

This summary highlights selected information that is presented in greater detail elsewhere in this prospectus. This summary does not contain all of the information you should consider before investing in our Class A common stock. You should read this entire prospectus carefully, including the sections titled "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations," and our consolidated financial statements and the related notes included elsewhere in this prospectus before making an investment decision. Unless the context otherwise requires, the terms "The Trade Desk," "the Company," "we," "us" and "our" refer to The Trade Desk, Inc. and its consolidated subsidiaries.

Our Company

Our company provides a technology platform for ad buyers.

With our self-serve platform, ad buyers are able to share their customized messages and ideas with the people and in the context they deliberately choose.

Our mission is to help our clients compete in the marketplace of ideas—the place in media and public discourse where ideas and messages compete in the open market for the mindshare of men and women around the world. Since most traditional and digital media is primarily monetized with advertising, ads are the currency of media and the Internet, and therefore at the center of the marketplace of ideas.

Our platform makes media monetization more effective. Instead of disrupting the foundation of media and advertising, we enable it. By offering compelling improvements in effectiveness, efficiency and reporting, we aim to change media and advertising globally.

Our platform makes it possible to message specific ideas to specific people. We give advertisers of all sizes the power to have simultaneous 1-to-1 customized interactions with billions of people around the world. Most advertising dollars are spent on awareness, where a brand pushes new information and ideas to a broad audience. Conversely, search engines respond to specific requests from individuals for information. Our technology combines the best of both, making it possible to push out a precise idea or message to a targeted audience with global scale.

Founded by some of the pioneers of the programmatic ad market, we established our company in 2009 with the intent to make advertising better by deploying massive amounts of data. By providing ad buyers with tools to leverage their first-party data as well as third-party data, we aim to provide a higher return on every advertising dollar spent. While our technology platform is deployed to directly serve ad buyers, the entire advertising marketplace benefits—publishers and content creators can experience a higher yield on their inventory, while consumers can receive advertising that is more relevant and interesting to them.

Most consumers are unaware that when they land on a webpage, watch a video, use a mobile app or watch an Internet-connected TV, there is often an auction for advertising inventory being run in about 1/10^th of one second behind the scenes as the content loads. Our platform provides access to approximately 3.2 million ad spots on average every second for our clients to bid on across millions of different scaled media sources—websites, shows, channels, stations and streams. Our technology makes it possible for ad buyers to compete in those real-time auctions. Our platform helps our clients determine what ad will display and what price they should pay for every ad opportunity a buyer can consider.

In 2015, approximately $639.6 billion was spent on global advertising (including approximately $237.2 billion on TV advertising and approximately $51.1 billion on display advertising), according to International Data Corporation, or IDC, and approximately $14.2 billion was transacted in the

programmatic advertising spot market via real-time marketplaces, according to Magna Global. We aim to power every agent of every advertiser in both the spot and forward markets, including upfront purchases, for programmatic advertising.

We also believe that the efficiency of programmatic advertising will lead to a greater percentage of every advertising dollar ending up in the pocket of publishers. Publishers can now generate revenue without the large sales forces that were required in the past. Higher revenue yields and lower operating costs make it possible for publishers to increase their investment in creating high quality content.

Programmatic advertising is currently a small portion of total global advertising spend. Largely because of the price discovery benefits, we believe eventually a vast majority of advertising will be transacted programmatically.

We enable the programmatic marketplace with our self-serve platform. The unique architecture of our platform allows users access to highly granular targeting and reporting options, which we refer to as expressiveness. When combined with our data management capability and first-party data, our clients can reach their highly specified audiences with customized messages and generate favorable campaign outcomes.

By using our technology and the reach of the Internet, we can power this data-driven 1-to-1 messaging with massive global scale. We believe in order to do this effectively, we have to be a buy-side only platform across a spectrum of media, which we refer to as omnichannel. As the biggest brands desire to communicate with consumers worldwide, we have to be global, which is why we have employees and offices around the world.

We derive nearly all of our revenue from ongoing master service agreements that give users constant access to our platform, instead of insertion orders, which typically are one-off deals to run single campaigns.

We have grown faster than the programmatic market and have achieved significant revenue scale with $552.3 million in gross spend in 2015. Our revenue was $113.8 million in 2015, representing a growth rate of 156% over $44.5 million in 2014, while programmatic advertising spend in the industry grew from $10 billion to $14 billion, according to Magna Global, representing a growth rate of 40% over 2014.

We generated net income of $5,000 in 2014 and $15.9 million in 2015. We generated $5.7 million of Adjusted EBITDA in 2014 and $39.2 million in 2015. Our net income was $5.7 million for the six months ended June 30, 2015 and $6.6 million for the six months ended June 30, 2016. Our Adjusted EBITDA was $11.1 million for the six months ended June 30, 2015 and $20.1 million for the six months ended June 30, 2016. Adjusted EBITDA is a financial measure not presented in accordance with generally accepted accounting principles, or GAAP. For a definition of Adjusted EBITDA, an explanation of our management's use of this measure and a reconciliation of Adjusted EBITDA to net income, see footnote 3 in the section captioned "Selected Consolidated Financial Data."

Our Industry

Since the introduction of ad-funded television in the middle of the 20^th century and continuing through the present day, most advertising inventory has been transacted based on a rate card. Publishers, content owners, and their agents set a price for their inventory, and buyers place an order to purchase that inventory. Similar to how the equities and commodities markets have transitioned from paper transactions on trading floors to electronic trading, advertising is transitioning from manual to programmatic.

Several trends happening in parallel are revolutionizing the way that advertising is bought and sold. Some of the key industry trends are:

Media is Becoming Digital. Media is increasingly becoming digital as a result of advances in technology and changes in consumer behavior. This shift has enabled unprecedented options for advertisers to target and measure their advertising campaigns across nearly every media channel and device. The digital advertising market is a significant and growing part of the total advertising market. According to IDC, global advertising spend was approximately $639.6 billion in 2015 and is expected to grow to $784.1 billion in 2020, a compound annual growth rate of 4.2%. Also, according to IDC, global digital advertising spend was $177.3 billion in 2015 and is expected to grow to $315.7 billion in 2020, a compound annual growth rate of 12.2%. We believe that the market is evolving and that advertisers will shift more spend to digital media. Since media is becoming increasingly digital, decisions based on consumer and behavioral data are more prevalent.

Fragmentation of Audience. As digital media grows, audience fragmentation is accelerating. A growing "long tail" of websites and content presents a challenge for advertisers trying to reach a large audience. Audience fragmentation has substantially impacted TV content distribution, perhaps more than any other channel, which we believe is setting up significant change in how TV advertising inventory is monetized. Mirroring the fragmentation occurring in content, the number of devices used by individual consumers has increased. Both of these fragmentation trends are opportunities for technology companies that can consolidate and simplify media buying options for advertisers and their agencies.

Shift to Programmatic Advertising. We believe that the advertising industry is in the early stages of a shift to programmatic advertising, which is the ability to buy and sell advertising inventory electronically. Initially available for digital display advertising and transacted through real-time bidding platforms, programmatic advertising has evolved and is increasingly being used to transact across a wide range of advertising inventory, including display, mobile, video and audio among other inventory types. In particular, we believe that TV advertising is just beginning its transition to programmatic.

Automation of Ad Buying. The growing complexity of digital advertising has increased the need for automation. Technology that enables fast, accurate and cost-effective decision-making through the application of computer algorithms that use extensive data sets has become critical for the success of digital advertising campaigns. Using programmatic inventory buying tools, advertisers are able to automate their campaigns, providing them with better price discovery, on an impression by impression basis. As a result, advertisers are able to purchase the advertising inventory they value the most, pay less for advertising inventory they do not value as much, and abstain from buying advertising inventory that does not fit their campaign parameters.

Increased Use of Data. Advances in software and hardware and the growing use of the Internet have made it possible to collect and rapidly process massive amounts of user data. Data vendors are able to collect user information across a wide range of Internet properties and connected devices, aggregate it and combine it with other data sources. This data is then made non-identifiable and available within seconds based on specific parameters and attributes. Advertisers can integrate this targeting data with their own or an agency's proprietary data relating to client attributes, the advertisers' own store locations and other related characteristics. Through the use of these data sources, together with real-time feedback from consumer reactions to the ads, programmatic advertising increases the value of impressions for advertisers, inventory owners, content creators and viewers who receive more relevant ads.

Driven by industry trends, programmatic advertising is expected to grow from $14.2 billion during 2015 to $36.8 billion by 2019, according to Magna Global. We believe that programmatic advertising will grow as more content providers, content distributors and advertisers are able to achieve its benefits.

In addition, we expect that programmatic advertising will help grow the overall advertising market by enabling more advertisers to deploy more spend across a broader range of inventory channels.

What We Do

We are a technology company that empowers advertising agencies and helps them purchase advertising more efficiently and effectively. We provide an intuitive self-serve platform that enables our clients to manage data-driven, digital advertising campaigns using their own teams.

•: We Are an Enabler, Not a Disruptor. With our self-serve platform, we enable advertising agencies and service providers. We do not compete with our clients by selling our platform directly to their advertisers. Our self-service technology platform provides control to our clients and gives us the benefits of a highly scalable business model.
•: We Are Exclusively Focused on the Buy-Side. We focus on buyers since they control the advertising budgets. Also, the supply of digital advertising inventory exceeds demand, and accordingly we believe it is a buyer's market. We also believe that by aligning our business only with buyers, we are able to avoid inherent conflicts of interest that exist when serving both the buy- and sell-side. This focus allows us to build trust with clients, many of whom incorporate their proprietary data into our platform.
•: We Are Data-Driven. Our technology platform was founded on the principle that data-driven decisions would be the future of advertising. We built a data management platform first, before building our ad buying technology. While data from disparate third-party data providers can improve campaign performance, our clients' success often relies largely on our ability to ingest first-party data from brands and their agencies to enable intelligent decisioning that optimizes advertising campaigns.
•: We Do Not Arbitrage Advertising Inventory. To further align our interests with those of our clients, we do not buy advertising inventory in order to resell it to our clients for a profit. Instead, we provide our clients with a technology platform that allows them to manage their omnichannel advertising campaigns, on a self-serve basis and with full transparency. We derive substantially all of our revenue from ongoing master service agreements with our clients rather than episodic insertion orders.
•: We Are a Clear Box, Not a Black Box. Our platform is transparent and shows our clients their costs of advertising inventory, data, our platform fee and detailed performance metrics on their advertising campaigns. Our clients directly access and execute campaigns on our platform, control all facets of inventory purchasing decisions, and receive detailed, real-time reporting on all their advertising campaigns.
•: We Are an Open Platform. Clients can customize and build their own features on top of our platform. Clients may use our application programming interfaces, or APIs, to, for example, design their own user interface, bulk manage advertising campaigns, and link other systems including ad servers or reporting tools. As of June 30, 2016, all of our top 10 clients used our APIs.
•: We Are Omnichannel. Our platform enables our clients to deliver unified advertising campaigns across multiple devices, including computers, smartphones, tablets, gaming consoles, digital TV and broadcast TV. We also support multiple formats, including display, video, broadcast TV, connected TV, mobile web, in-app mobile and native. The breadth of data that we collect from a multitude of data sources across all channels gives our clients a holistic view of audiences, enabling more effective targeting across different channels.

Our Strengths

We believe the following attributes and capabilities form our core strengths and provide us with competitive advantages:

•: Expressiveness of Our Platform. Our platform allows clients to easily define and manage advertising campaigns with multiple targeting parameters that may result in quadrillions of permutations, which we refer to as expressiveness. We believe that expressiveness provides clients with the ability to target audiences with an extremely high level of precision.
•: Scalable Self-Service Model. We offer a self-service model that lets clients direct their own purchases of advertising inventory without extensive involvement by our personnel. This model helps us scale efficiently and has allowed us to grow our business at a faster pace than the growth of our sales and support organization.
•: Loyal Client Base. We had approximately 389 clients, including the advertising industry's largest agencies, as of December 31, 2015. Many of our clients use our platform regularly as part of their digital advertising purchase workflow, creating ongoing relationships. As a result, our clients are loyal, with over 95% client retention during 2014 and 2015. In addition, our clients typically grow their use of our platform over time, with our clients who spent with us in 2014 increasing their spend on our platform by 135% during 2015.
•: Extensive Data Access. Our clients can easily buy targeting data from over 80 sources through our platform. We also provide clients access to our proprietary data, which increases with continued use of our platform. We believe that the integration of data and decisioning within a single platform enables us to better serve our clients.
•: Focus on Innovation. Our focus on innovation enables us to enhance our platform rapidly for our clients in a constantly evolving industry. We have designed the technology for our platform to enable us to develop new features and make changes quickly and efficiently. For example, we enhanced our platform with 46 releases of updated features and increased functionality in 2015.
•: Scaled and Profitable Business Model. We have grown our business rapidly while achieving profitability, demonstrating the power of our platform, our strong client relationships and our business model. During 2015, gross spend was $552.3 million, helping us generate $113.8 million in revenue, up 156% from 2014. In 2015, net income was $15.9 million and Adjusted EBITDA increased by 589% to $39.2 million. See footnote 3 in the section captioned "Selected Consolidated Financial Data."

Our Growth Strategy

The key elements of our long-term growth strategy include:

•: increasing our share of existing clients' digital advertising spend;
•: growing our client base;
•: expanding our omnichannel capabilities;
•: extending our reach to TV;
•: continuing to innovate in technology and data; and
•: expanding our international presence.

Risk Factors Summary

Our business is subject to numerous risks and uncertainties, including those in the section captioned "Risk Factors" beginning on page 13 and elsewhere in this prospectus. These risks include, but are not limited to, the following:

•: our limited operating history, which makes it difficult to evaluate our business and prospects and may increase the risks associated with your investment;
•: the loss of advertising agencies as clients, which could significantly harm our business, operating results and financial condition;
•: our failure to innovate and make the right investment decisions in our offerings and platform, which could compromise our ability to attract and retain advertisers and advertising agencies, and cause our revenue and results of operations to decline;
•: if the market for programmatic advertising, which is relatively new and evolving, develops slower or differently than we expect, our business, growth prospects and financial condition would be adversely affected;
•: our failure to manage our growth effectively, which could cause our business to suffer and have an adverse effect on our financial condition and operating results;
•: the market in which we participate is intensely competitive, and we may not be able to compete successfully with our current or future competitors;
•: we have identified material weaknesses in our internal control over financial reporting and, if our remediation of these material weaknesses is not effective, or if we fail to maintain an effective system of internal control over financial reporting in the future, we may not be able to accurately or timely report our financial condition or results of operations, which may adversely affect investor confidence in us and the price of our common stock;
•: insiders will continue to have substantial control over our company after this offering, including as a result of the dual class structure of our common stock, which could limit your ability to influence the outcome of key decisions, including a change of control;
•: our sales cycle can take significant time before executing a client agreement, which may make it difficult to project when, if at all, we will obtain new clients and when we will generate revenue from those clients;
•: we are subject to payment-related risks and, if our clients do not pay or dispute their invoices, our business, financial condition and operating results may be adversely affected;
•: because our business is primarily dependent on advertisers purchasing display advertising, a decrease in the use of display advertising would harm our business, growth prospects, financial condition and results of operations; and
•: if our access to quality advertising inventory is diminished, our revenue could decline and our growth could be impeded.

Corporate Information

We were incorporated in Delaware in November 2009. Our principal executive offices are located at 42 N. Chestnut Street, Ventura, California 93001, and our telephone number is (805) 585-3434. Our website address is www.thetradedesk.com. The information on, or that can be accessed through, our website is not incorporated by reference into this prospectus, and you should not consider any such information as part of this prospectus or when deciding whether to purchase our Class A common stock.

The Trade Desk and our other registered or common law trademarks, service marks or trade names appearing in this prospectus are the property of The Trade Desk, Inc. Other trademarks, service marks or trade names appearing in this prospectus are the property of their respective owners. We have omitted the ® and ™ designations, as applicable, for the trademarks used in this prospectus.

Implications of Being an Emerging Growth Company

The Jumpstart Our Business Startups Act, or the JOBS Act, was enacted in April 2012 with the intention of encouraging capital formation in the United States and reducing the regulatory burden on newly public companies that qualify as "emerging growth companies." We are an emerging growth company within the meaning of the JOBS Act. As an emerging growth company, we may take advantage of certain exemptions from various public reporting requirements, including the requirement that our internal control over financial reporting be audited by our independent registered public accounting firm pursuant to Section 404 of the Sarbanes-Oxley Act of 2002, certain requirements related to the disclosure of executive compensation in this prospectus and in our periodic reports and proxy statements, and the requirement that we hold a non-binding advisory vote on executive compensation and any golden parachute payments. We may take advantage of these exemptions until we are no longer an emerging growth company.

We will remain an emerging growth company until the earliest to occur of: (1) the last day of the fiscal year in which we have $1.0 billion or more in annual gross revenue; (2) the date we qualify as a "large accelerated filer" with, among other things, at least $700 million of equity securities held by non-affiliates; (3) the date on which we have issued, in any three-year period, more than $1.0 billion in non-convertible debt securities; and (4) the last day of the fiscal year ending after the fifth anniversary of our initial public offering.

For certain risks related to our status as an emerging growth company, see the section captioned "Risk Factors" beginning on page 13.

The Offering


Class A common stock offered by us		4,666,667 shares
Class A common stock outstanding after this offering		4,666,767 shares
Class B common stock to be outstanding after this offering		33,561,787 shares
Total Class A and Class B common stock to be outstanding after this offering		38,228,554 shares
Option to purchase additional shares of Class A common stock from us and the selling stockholders		700,000 shares
Use of proceeds		We estimate that the net proceeds to us from the sale of shares of our Class A common stock in this offering will be approximately $69.8 million, based upon the assumed initial public offering price of $17.00 per share, which is the midpoint of the estimated offering price range set forth on the cover page of this prospectus, and after deducting underwriting discounts and commissions, and estimated offering expenses payable by us.
		We currently intend to use a significant portion of the net proceeds from this offering for general corporate purposes, including working capital, funding the expansion of our business, including expanding our sales and marketing programs, and making investments in our technology and development teams to support the development of new applications and features for, and enhancements of, our platform. We may also use a portion of the net proceeds from this offering for the acquisition of, or investment in, technologies or businesses that complement our business, although we have no present commitments or agreements to enter into any such acquisitions or make any such investments.
		In March 2016, we paid off all remaining principal and interest due under a previous credit facility. Pursuant to the terms of this facility, upon the occurrence of our initial public offering, we remain obligated to pay the lenders a fee of $750,000. We intend to satisfy this obligation with the net proceeds to us from this offering.
		We will not receive any proceeds from the sale of shares of common stock by the selling stockholders. See the section captioned "Use of Proceeds" for a more complete description of the intended use of proceeds from this offering.


Directed Share Program		The underwriters have reserved for sale, at the initial public offering price, up to 466,666 shares of Class A common stock being sold pursuant to this offering, which equals approximately 10% of such shares being sold. Such shares are being reserved for sale to directors, officers, employees, business associates, advisors and friends of the Company. Any such shares purchased by our directors, officers and employees will be subject to the 180-day contractual lock-up described more fully in "Underwriting." All other such reserved shares purchased will be subject to a 30-day contractual lock-up. The number of shares available for sale to the general public in this offering will be reduced to the extent these persons purchased reserved shares. Any reserved shares not purchased will be offered by the underwriters to the general public on the same terms as the other shares.
Voting Rights		Shares of Class A common stock will be entitled to one vote per share.
		Shares of Class B common stock will be entitled to ten votes per share.
		Holders of our Class A common stock and Class B common stock will generally vote together as a single class, unless otherwise required by law.
		Assuming no exercise of the underwriters' option to purchase additional shares, following this offering, outstanding shares of Class B common stock will represent approximately 99% of the voting power of our outstanding capital stock, and outstanding shares of common stock held by our executive officers, directors and holders of more than 5% of our capital stock will represent approximately 85% of the voting power of our outstanding capital stock.
		See the section captioned "Description of Capital Stock."
Proposed trading symbol on The NASDAQ Global Market		"TTD"

The total number of shares of Class A common stock and Class B common stock that will be outstanding after this offering includes 4,666,767 shares of our Class A common stock and 33,561,787 shares of our Class B common stock, and excludes, in each case as of June 30, 2016:

•

an aggregate of 5,057,961 shares of Class B common stock issuable upon the exercise of outstanding options under The Trade Desk, Inc. 2010 Stock Plan, or our 2010 Plan, and The Trade Desk, Inc. 2015 Equity Incentive Plan, or our 2015 Plan, with a weighted-average exercise price of approximately $1.55 per share; and

•

shares of Class A common stock, subject to annual increase, reserved for future grant or issuance under our 2016 Incentive Award Plan, or our 2016 Plan, which will become effective upon the completion of this offering, consisting of:

•: 4,000,000 shares of Class A common stock reserved under our 2016 Plan; and
•: an additional number of shares of Class A common stock equal to the number of shares of Class B common stock subject to outstanding awards under the 2015 Plan as of the effective date of the 2016 Plan and which are forfeited or lapse unexercised thereafter.

Except as otherwise indicated, all information in this prospectus assumes:

•: that our amended and restated certificate of incorporation, which we will file in connection with this offering, is in effect;
•: a 1-for-3 reverse stock split of our common stock and a proportional adjustment to the conversion ratio of our convertible preferred stock, which was effected on September 2, 2016;
•: the reclassification of 11,035,426 shares of our common stock into an equivalent number of shares of Class B common stock and the authorization of our Class A common stock;
•: the automatic conversion of outstanding warrants exercisable for 1,382,505 shares of our convertible preferred stock into warrants exercisable for 460,834 shares of our Class B common stock and the net exercise of such warrants resulting in the issuance of 447,823 shares of Class B common stock based upon an assumed initial public offering price of $17.00 per share (the midpoint of the price range set forth on the cover page of the prospectus) immediately prior to the completion of this offering;
•: the automatic conversion of all shares of our outstanding convertible preferred stock into an aggregate of 22,078,638 shares of Class B common stock immediately prior to the completion of this offering;
•: the conversion on September 16, 2016 of 100 shares of Class B common stock into 100 shares of Class A common stock; and
•: no exercise of the underwriters' option to purchase additional shares.

We refer to our Series Seed, Series A-1, Series A-2, Series A-3, Series B and Series C convertible preferred stock collectively as "convertible preferred stock" in this prospectus.

Summary Consolidated Financial Data

The consolidated statements of operations data for the years ended December 31, 2014 and 2015 is derived from our audited consolidated financial statements included elsewhere in this prospectus. The summary consolidated statements of operations data for the six months ended June 30, 2015 and 2016 and the summary consolidated balance sheet data as of June 30, 2016 are derived from our unaudited condensed consolidated financial statements included elsewhere in this prospectus. Our unaudited interim condensed consolidated financial statements were prepared on a basis consistent with that used to prepare our audited annual consolidated financial statements and include, in the opinion of management, all adjustments, consisting of normal recurring items, necessary for the fair statement of the condensed consolidated financial statements.

You should read this data together with our audited consolidated financial statements and related notes, as well as the information under the captions "Selected Consolidated Financial Data" and "Management's Discussion and Analysis of Financial Condition and Results of Operations," included elsewhere in this prospectus. Our historical results are not necessarily indicative of our future results, and results for any interim period below are not necessarily indicative of results for the full year.

	Year Ended December 31,					Six Months Ended June 30,

	2014			2015		2015		2016
	(in thousands, except per share data)
Consolidated Statements of Operations Data:
Revenue	$	44,548		$	113,836	$	42,410	$	77,560
Operating expenses⁽¹⁾:
Platform operations		12,559			22,967		9,642		16,195
Sales and marketing		14,590			26,794		11,692		19,682
Technology and development		7,250			12,819		5,096		10,402
General and administrative		9,385			13,276		5,177		12,851

Total operating expenses		43,784			75,856		31,607		59,130

Income from operations		764			37,980		10,803		18,430
Total other expense, net		1,707			8,125		1,436		6,524

Income (loss) before income taxes		(943	)		29,855		9,367		11,906
Provision for (benefit from) income taxes		(948	)		13,926		3,693		5,348

Net income	$	5		$	15,929	$	5,674	$	6,558



Net income (loss) attributable to common stockholders⁽²⁾	$	—		$	8,764	$	5,470	$	(40,651	)



Earnings (loss) per share—basic⁽²⁾	$	—		$	0.85	$	0.54	$	(3.74	)



Earnings (loss) per share—diluted⁽²⁾	$	—		$	0.39	$	0.15	$	(3.74	)



Pro forma earnings per share—basic⁽²⁾				$	0.68			$	0.34



Pro forma earnings per share—diluted⁽²⁾				$	0.60			$	0.30



Non-GAAP Financial and Operating Data:
Adjusted EBITDA⁽³⁾	$	5,683		$	39,159	$	11,105	$	20,073



Gross spend⁽⁴⁾	$	211,266		$	552,325	$	200,013	$	404,815



Gross billings⁽⁴⁾	$	201,804		$	529,975	$	192,990	$	389,245

	As of June 30, 2016

	Actual			Pro Forma⁽⁵⁾		Pro Forma As Adjusted⁽⁶⁾
	(in thousands)
Consolidated Balance Sheet Data:
Cash	$	37,610		$	37,610	$	108,392
Accounts receivable, net		236,737			236,737		236,737
Total assets		294,951			294,951		363,510
Accounts payable		164,296			164,296		163,825
Long-term debt, net of current portion		56,623			56,623		56,623
Total liabilities		240,000			232,057		231,586
Convertible preferred stock		83,241			—		—
Total stockholders' equity (deficit)		(28,290	)		62,894		131,924

⁽¹⁾: Includes stock-based compensation expense as follows:

	Year Ended December 31,				Six Months Ended June 30,

	2014		2015		2015		2016
	(in thousands)
Platform operations	$	14	$	71	$	17	$	39
Sales and marketing		50		127		54		117
Technology and development		909		85		29		114
General and administrative		3,572		91		35		122

Total	$	4,545	$	374	$	135	$	392

See Note 11 to our audited consolidated financial statements and Note 8 to our unaudited condensed consolidated financial statements in this prospectus for more information regarding stock-based compensation expense.

⁽²⁾: See Note 3 to our audited consolidated financial statements and Note 3 to our unaudited condensed consolidated financial statements in this prospectus for more information regarding earnings (loss) per share—basic and diluted and pro forma earnings per share—basic and diluted.
⁽³⁾: For information on how we compute Adjusted EBITDA and a reconciliation of Adjusted EBITDA to net income on a GAAP basis, see footnote 3 in the section captioned "Selected Consolidated Financial Data."
⁽⁴⁾: For information on how we compute gross spend and gross billings, see footnotes 4 and 5, respectively, in the section captioned "Selected Consolidated Financial Data."
⁽⁵⁾: The unaudited pro forma balance sheet data as of June 30, 2016 reflects (1) the automatic conversion of all outstanding shares of our convertible preferred stock into an aggregate of 22,078,638 shares of common stock and (2) the conversion of warrants to purchase 1,382,505 shares of convertible preferred stock into warrants to purchase 460,834 shares of Class B common stock and the net exercise of such warrants resulting in the issuance of 447,823 shares of Class B common stock based upon an assumed initial public offering price of $17.00 per share (the midpoint of the price range set forth on the cover page of the prospectus) and the reclassification of the preferred stock warrant liabilities to additional paid-in capital. Each share of convertible preferred stock will automatically convert into shares of common stock at its then effective conversion rate immediately upon the earlier of (1) the first closing of a sale of shares of our common stock to the public in a firm commitment underwritten initial public offering pursuant to an effective registration statement under the Securities Act, with proceeds to us of not less than $50.0 million (net of underwriting discounts and commissions), and (2) the date specified by a vote of the holders of at least a majority of all then-outstanding shares of convertible preferred stock, voting together as a single class on an as-converted to common stock basis provided that each series of convertible preferred stock will not be converted as a result of such vote without the consent of the holders of a majority of the shares of such series of convertible preferred stock then outstanding.
⁽⁶⁾: The pro forma as adjusted column gives effect to the pro forma adjustments set forth in footnote 5 hereto and (1) the issuance and sale by us of 4,666,667 shares of our Class A common stock in this offering at an assumed initial public offering price of $17.00 per share, which is the midpoint of the price range on the cover page of this prospectus, after deducting the underwriting discounts and commissions and estimated offering expenses payable by us and (2) the payment by us of the $750,000 fee that we are obligated to pay to the lenders of our previous 2015 credit facility in connection with this offering.

Investing in our Class A common stock involves a high degree of risk. You should consider carefully the risks and uncertainties described below, together with all of the other information in this prospectus, including the consolidated financial statements and the related notes, before deciding whether to purchase shares of our Class A common stock. The risks and uncertainties described below include those that we consider material and that we are currently aware of, but are not the only ones we face. If any of the following risks is realized, our business, financial condition, results of operation and prospects could be materially and adversely affected. In that event, the market price of our Class A common stock could decline and you could lose part or all of your investment.

We have a limited operating history, which makes it difficult to evaluate our business and prospects and may increase the risks associated with your investment.

We were incorporated in 2009 and, as a result, have only a limited operating history upon which our business and prospects may be evaluated. Although we have experienced substantial revenue growth in our limited operating history, we may not be able to sustain this rate of growth or maintain our current revenue levels. We have encountered and will continue to encounter risks and challenges frequently experienced by growing companies in rapidly developing industries, including risks related to our ability to:

We cannot assure you that we will be successful in addressing these and other challenges we may face in the future. If we are unable to do so, our business may suffer, our revenue and operating results may decline and we may not be able to achieve further growth or sustain profitability.

Our failure to maintain and grow our client base and spend through our platform may negatively impact our revenue and business.

To sustain or increase our revenue, we must regularly add new clients and encourage existing clients to maintain or increase the amount of advertising inventory purchased through our platform and adopt new features and functionalities that we add to our platform. If competitors introduce lower cost or differentiated offerings that compete with or are perceived to compete with ours, our ability to sell access to our platform to new or existing clients could be impaired. We have spent significant effort in cultivating our relationships with advertising agencies, which has resulted in an increase in the budgets allocated to, and the amount of advertising purchased on, our platform. However, it is possible that we may reach a point of saturation at which we cannot continue to grow our revenue from such agencies

because of internal limits that advertisers may place on the allocation of their advertising budgets to digital media to a particular provider or otherwise. While we generally have master services agreements in place for our clients, such agreements allow our clients to change the amount of spend through our platform or terminate our services with limited notice. Our clients typically have relationships with different providers and there is limited cost to moving budgets to our competitors. As a result, we may have limited visibility as to our future advertising revenue streams. We cannot assure you that our clients will continue to use our platform or that we will be able to replace, in a timely or effective manner, departing clients with new clients that generate comparable revenue. If a major client representing a significant portion of our business decides to materially reduce its use of our platform or to cease using our platform altogether, it is possible that our revenue could be significantly reduced.

The loss of advertising agencies as clients could significantly harm our business, operating results and financial condition.

Our client base consists primarily of advertising agencies. We do not have exclusive relationships with advertising agencies and we depend on agencies to work with us as they embark on advertising campaigns for advertisers.

The loss of agencies as clients could significantly harm our business, operating results and financial condition. If we fail to maintain satisfactory relationships with an advertising agency, we risk losing business from the advertisers represented by that agency.

Advertisers may change advertising agencies. If an advertiser switches from an agency that utilizes our platform to one that does not, we will lose revenue from that advertiser. In addition, some advertising agencies have their own relationships with suppliers of advertising inventory and can directly connect advertisers with such suppliers. Our business may suffer to the extent that advertising agencies and inventory suppliers purchase and sell advertising inventory directly from one another or through intermediaries other than us.

We had approximately 389 clients, consisting primarily of advertising agencies, as of December 31, 2015. Many of these agencies are owned by holding companies, where decision making is decentralized such that purchasing decisions are made, and relationships with advertisers, are located, at the agency, local branch or division level. If all of our individual client contractual relationships were aggregated at the holding company level, Omnicom Group Inc. and WPP plc would each represent more than 10% of our gross billings for 2015.

In most cases, we enter into separate contracts and billing relationships with the individual agencies and account for them as separate clients. However, some holding companies for these agencies may choose to exert control over the individual agencies in the future. If so, any loss of relationships with such holding companies and, consequently, of their agencies, local branches or divisions, as clients could significantly harm our business, operating results and financial condition.

If we fail to innovate and make the right investment decisions in our offerings and platform, we may not attract and retain advertisers and advertising agencies and our revenue and results of operations may decline.

Our industry is subject to rapid and frequent changes in technology, evolving client needs and the frequent introduction by our competitors of new and enhanced offerings. We must constantly make investment decisions regarding offerings and technology to meet client demand and evolving industry standards. We may make wrong decisions regarding these investments. If new or existing competitors have more attractive offerings, we may lose clients or clients may decrease their use of our platform. New client demands, superior competitive offerings or new industry standards could require us to make unanticipated and costly changes to our platform or business model. If we fail to adapt to our rapidly changing industry or to evolving client needs, demand for our platform could decrease and our business, financial condition and operating results may be adversely affected.

Failure to manage our growth effectively could cause our business to suffer and have an adverse effect on our financial condition and operating results.

We have experienced significant growth in a short period of time. To manage our growth effectively, we must continually evaluate and evolve our organization. We must also manage our employees, operations, finances, technology and development and capital investments efficiently. Our efficiency, productivity and the quality of our platform and client service may be adversely impacted if we do not train our new personnel, particularly our sales and support personnel, quickly and effectively, or if we fail to appropriately coordinate across our organization. Additionally, our rapid growth may place a strain on our resources, infrastructure and ability to maintain the quality of our platform. You should not consider our revenue growth and levels of profitability in recent periods as indicative of future performance. In future periods, our revenue or profitability could decline or grow more slowly than we expect. Failure to manage our growth effectively could cause our business to suffer and have an adverse effect on our financial condition and operating results.

The market for programmatic buying for advertising campaigns is relatively new and evolving. If this market develops slower or differently than we expect, our business, growth prospects and financial condition would be adversely affected.

The substantial majority of our revenue has been derived from clients that programmatically purchase advertising inventory through our platform. We expect that spending on programmatic ad buying will continue to be our primary source of revenue for the foreseeable future, and that our revenue growth will largely depend on increasing spend through our platform. The market for programmatic ad buying is an emerging market, and our current and potential clients may not shift quickly enough to programmatic ad buying from other buying methods, reducing our growth potential. If the market for programmatic ad buying deteriorates or develops more slowly than we expect, it could reduce demand for our platform, and our business, growth prospects and financial condition would be adversely affected.

In addition, revenue may not necessary grow at the same rate as spend on our platform. Growth in spend may outpace growth in our revenue as the market for programmatic buying for advertising matures due to a number of factors including quantity discounts and product, media, client and channel mix shifts. For example, TV advertising typically entails relatively large advertising budgets that carry a smaller fee as a percentage of spend. Growth in the use of our platform for TV advertising could impact the rate of our revenue growth relative to the rate of growth in spend on our platform. A significant change in revenue as a percentage of spend could reflect an adverse change in our business and growth prospectus. In addition, any such fluctuations, even if they reflect our strategic decisions, could cause our performance to fall below the expectations of securities analysts and investors, and adversely affect the price of our common stock.

The market in which we participate is intensely competitive, and we may not be able to compete successfully with our current or future competitors.

We operate in a highly competitive and rapidly changing industry. With the introduction of new technologies and the influx of new entrants to the market, we expect competition to persist and intensify in the future, which could harm our ability to increase revenue and maintain profitability. New technologies and methods of buying advertising present a dynamic competitive challenge, as market participants offer multiple new products and services, such as analytics, automated media buying and exchanges, aimed at capturing advertising spend. In addition to existing competitors and intermediaries, we may also face competition from new companies entering the market, which may include large established companies, all of which currently offer, or may in the future offer, products and services that result in additional competition for advertising spend or advertising inventory.

Further, we derive a significant portion of our revenue from the display advertising market, which is rapidly evolving, highly competitive, complex and fragmented. We face significant competition in this market which we expect will intensify in the future. We currently compete for advertising spend with large, well-established companies as well as smaller, privately-held companies. Some of our larger competitors with more resources may be better positioned to execute on advertising campaigns conducted over multiple channels such as social media, mobile and video.

We may also face competition from companies that we do not yet know about or do not yet exist. If existing or new companies develop, market or resell competitive high-value marketing products or services, acquire one of our existing competitors or form a strategic alliance with one of our competitors, our ability to compete effectively could be significantly compromised and our results of operations could be harmed.

Our current and potential competitors may have significantly more financial, technical, marketing and other resources than we have, allowing them to devote greater resources to the development, promotion, sale and support of their products and services. They may also have more extensive advertiser bases and broader publisher relationships than we have, and may have longer operating histories and greater name recognition. As a result, these competitors may be better able to respond quickly to new technologies, develop deeper advertiser relationships or offer services at lower prices. Any of these developments would make it more difficult for us to sell our platform and could result in increased pricing pressure, increased sales and marketing expense or the loss of market share.

Economic downturns and market conditions beyond our control could adversely affect our business, financial condition and operating results.

Our business depends on the overall demand for advertising and on the economic health of advertisers that benefit from our platform. Economic downturns or unstable market conditions may cause advertisers to decrease their advertising budgets, which could reduce spend though our platform and adversely affect our business, financial condition and operating results. As we explore new countries to expand our business, economic downturns or unstable market conditions in any of those countries could result in our investments not yielding the returns we anticipate.

We may experience fluctuations in our operating results, which could make our future operating results difficult to predict or cause our operating results to fall below analysts' and investors' expectations.

Our quarterly and annual operating results have fluctuated in the past and we expect our future operating results to fluctuate due to a variety of factors, many of which are beyond our control. Fluctuations in our operating results could cause our performance to fall below the expectations of analysts and investors, and adversely affect the price of our common stock. Because our business is changing and evolving rapidly, our historical operating results may not be necessarily indicative of our future operating results. Factors that may cause our operating results to fluctuate include the following:

Based upon the factors above and others beyond our control, we have a limited ability to forecast our future revenue, costs and expenses, and as a result, our operating results may, from time to time, fall below our estimates or the expectations of analysts and investors.

We often have long sales cycles, which can result in significant time between initial contact with a prospect and execution of a client agreement, making it difficult to project when, if at all, we will obtain new clients and when we will generate revenue from those clients.

Our sales cycle, from initial contact to contract execution and implementation can take significant time. Our sales efforts involve educating our clients about the use, technical capabilities and benefits of our platform. Some of our clients undertake an evaluation process that frequently involves not only our platform but also the offerings of our competitors. As a result, it is difficult to predict when we will obtain new clients and begin generating revenue from these new clients. Even if our sales efforts result in obtaining a new client, under our usage-based pricing model, the client controls when and to what extent it uses our platform. As a result, we may not be able to add clients, or generate revenue, as quickly as we may expect, which could harm our growth prospects.

We are subject to payment-related risks and, if our clients do not pay or dispute their invoices, our business, financial condition and operating results may be adversely affected.

Many of our contracts with advertising agencies provide that if the advertiser does not pay the agency, the agency is not liable to us, and we must seek payment solely from the advertiser, a type of arrangement called sequential liability. Contracting with these agencies, which in some cases have or may develop higher-risk credit profiles, may subject us to greater credit risk than if we were to contract directly with advertisers. This credit risk may vary depending on the nature of an advertising agency's aggregated advertiser base. We may also be involved in disputes with agencies and their advertisers over the operation of our platform, the terms of our agreements or our billings for purchases made by them through our platform. If we are unable to collect or make adjustments to bills to clients, we could incur write-offs for bad debt, which could have a material adverse effect on our results of operations for the periods in which the write-offs occur. In the future, bad debt may exceed reserves for such contingencies and our bad debt exposure may increase over time. Any increase in write-offs for bad debt could have a materially negative effect on our business, financial condition and operating results. Even if we are not paid by our clients on time or at all, we are still obligated to pay for the advertising

we have purchased for the advertising campaign, and as a consequence, our results of operations and financial condition would be adversely impacted.

A substantial portion of our business is from advertising agencies that do not pay us until they receive payment from the advertiser, resulting in an increased length of time between our payment for media inventory and our receipt of payment for use of our platform, and our ability to collect for non-payment may be limited to the advertiser, thereby increasing our risk of non-payment.

Substantially all of our platform spend is from advertising agencies. We are generally contractually required to pay advertising inventory and data suppliers within a negotiated period of time, regardless of whether our clients pay us on time, or at all. Additionally, while we attempt to negotiate long payment periods with our suppliers and shorter periods from our clients, we are not always successful. As a result, we often face a timing issue with our accounts payable on shorter cycles than our accounts receivables, requiring us to remit payments from our own funds, and accept the risk of bad debt.

This payment process will increasingly consume working capital if we continue to be successful in growing our business. In addition, we typically experience slow payment by advertising agencies as is common in our industry. In this regard, we had average days sales outstanding, or DSO, of 88 days, and average days payable outstanding, or DPO, of 64 days at June 30, 2016. We compute our DSO and DPO as of a given date based on our average trade receivables or trade payables, respectively, for the trailing 12-month period divided by, for DSO, average daily gross billings for the period, and for DPO, by the average daily cost of media, data and operating expenses over such period. The average trade receivables or trade payables are the average of the trade receivables or trade payables balances at the beginning and end of the 12-month period. Historically, our DSOs have fluctuated over time. If our DSOs increase significantly, and we are unable to borrow against these receivables on commercially acceptable terms, our working capital availability could be reduced, and as a consequence our results of operations and financial condition would be adversely impacted.

Due to this imbalance in our DSOs and DPOs, we rely on our credit facility to partially or completely fund our working capital requirements. We cannot assure you that as we continue to grow, our business will generate sufficient cash flow from operations or that future borrowings will be available to us under the credit facility in an amount sufficient to fund our working capital needs. If our cash flows and credit facility borrowings are insufficient to fund our working capital requirements, we may not be able to grow at the rate we currently expect or at all. In addition, in the absence of sufficient cash flows from operations, we might be unable to meet our obligations under our credit facility and we may therefore be at risk of default thereunder. We cannot assure you that we would be able to locate additional financing or increase amounts borrowed under our existing credit facility to on commercially reasonable terms or at all.

Our business is primarily dependent on advertisers buying display advertising. A decrease in the use of display advertising would harm our business, growth prospects, financial condition and results of operations.

Historically, our clients have predominantly used our platform to purchase display advertising inventory. We expect that display advertising will continue to be a significant channel used by our clients. Should our clients lose confidence in the value or effectiveness of display advertising, the demand for our platform could decline.

We are working to enhance our social, native, digital radio and television offerings, including the capability to buy ads on digital television using our platform. We refer to the ability to provide offerings across these channels as omnichannel. These markets may not reach the scale of display advertising, and our omnichannel offerings may not gain market acceptance. A decrease in the use of display advertising, or our inability to further penetrate display and other advertising channels, would harm our growth prospects, financial condition and results of operations.

If our access to quality advertising inventory is diminished, our revenue could decline and our growth could be impeded.

We must maintain a consistent supply of attractive ad inventory. Our success depends on our ability to secure quality inventory on reasonable terms across a broad range of advertising networks and exchanges, video, audio and mobile inventory, and social media platforms. The amount, quality and cost of inventory available to us can change at any time. A few inventory suppliers hold a significant portion of the programmatic inventory either generally or concentrated in a particular channel. For example, one supplier represented more than 10% of our accounts payable at June 30, 2016. In addition, we compete with companies with which we have business relationships. For example, Google is one of our largest advertising inventory suppliers in addition to being one of our competitors. If Google or a similarly situated company limits our access to advertising inventory, our business could be adversely affected. If our relationships with any of our suppliers were to cease, or if the material terms of these relationships were to change unfavorably, our business would be negatively impacted. Our suppliers are generally not bound by long-term contracts. As a result, there is no guarantee that we will have access to a consistent supply of quality inventory on favorable terms. If we are unable to compete favorably for advertising inventory available on real-time advertising exchanges, or if real-time advertising exchanges decide not to make their advertising inventory available to us, we may not be able to place advertisements or find alternative sources of inventory with comparable traffic patterns and consumer demographics in a timely manner. Furthermore, the inventory that we access through real-time advertising exchanges may be of low quality or misrepresented to us, despite attempts by us and our suppliers to prevent fraud and conduct quality assurance checks.

Inventory suppliers control the bidding process for the inventory they supply, and their processes may not always work in our favor. For example, suppliers may place restrictions on the use of their inventory, including prohibiting the placement of advertisements on behalf of specific advertisers. Through the bidding process, we may not win the right to deliver advertising to the inventory that is selected through our platform and may not be able to replace inventory that is no longer made available to us.

As new types of inventory, such as digital advertising for television, become available, we will need to expend significant resources to ensure we have access to such new inventory. Although television advertising is a large market, only a very small percentage of it is currently purchased through digital advertising exchanges. We are investing heavily in our programmatic television offering, including by increasing our workforce and by adding new features, functions and integrations to our platform. If the digital television advertising market does not grow as we anticipate or we fail to successfully serve such market, our growth prospects could be harmed.

Our success depends on consistently adding valued inventory in a cost-effective manner. If we are unable to maintain a consistent supply of quality inventory for any reason, client retention and loyalty, and our financial condition and operating results could be harmed.

Seasonal fluctuations in advertising activity could have a material impact on our revenue, cash flow and operating results.

Our revenue, cash flow, operating results and other key operating and performance metrics may vary from quarter to quarter due to the seasonal nature of our clients' spending on advertising campaigns. For example, clients tend to devote more of their advertising budgets to the fourth calendar quarter to coincide with consumer holiday spending. Moreover, advertising inventory in the fourth quarter may be more expensive due to increased demand for advertising inventory. Political advertising could also cause our revenue to increase during election cycles and decrease during other periods. Our historical revenue growth has masked the impact of seasonality, but if our growth rate declines or

seasonal spending becomes more pronounced, seasonality could have a material impact on our revenue, cash flow and operating results from period to period.

As our costs increase, we may not be able to generate sufficient revenue to sustain profitability.

We have expended significant resources to grow our business in recent years by increasing the offerings of our platform, growing our number of employees and expanding internationally into several countries. We anticipate continued growth that could require substantial financial and other resources to, among other things:

Investing in the foregoing, however, may not yield anticipated returns. Consequently, as our costs increase, we may not be able to generate sufficient revenue to sustain profitability.

We have identified material weaknesses in our internal control over financial reporting and, if our remediation of these material weaknesses is not effective, or if we fail to maintain an effective system of internal control over financial reporting in the future, we may not be able to accurately or timely report our financial condition or results of operations, which may adversely affect investor confidence in us and the price of our common stock.

As a public company, we will be required to maintain internal control over financial reporting and to report any material weaknesses in such internal control. Section 404 of the Sarbanes-Oxley Act of 2002, or the Sarbanes-Oxley Act, requires that we evaluate and determine the effectiveness of our internal control over financial reporting and, beginning with our second annual report following this offering, which we expect will cover our year ending December 31, 2017, provide a management report on internal control over financial reporting. A material weakness is a deficiency or combination of deficiencies in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of our financial statements will not be prevented or detected on a timely basis.

During 2015, we identified the following material weaknesses in our internal control over financial reporting:

These material weaknesses contributed to the restatement of previously issued 2014 financial statements and material adjustments in the 2015 financial statements principally, but not limited to, the following areas: presentation of revenue, capitalization of internal use software costs, accounting for preferred stock and preferred stock warrants, allowance for doubtful accounts and stock-based compensation.

During 2015 and 2016, we began taking steps to address the internal control deficiencies that contributed to the material weaknesses, including the following:

While we believe that these efforts will improve our internal control over financial reporting, the implementation of these measures is ongoing and will require validation and testing of the design and operating effectiveness of internal controls over a sustained period of financial reporting cycles. We cannot assure you that the measures we have taken to date, and are continuing to implement, will be sufficient to remediate the material weaknesses we have identified or avoid potential future material weaknesses. If the steps we take do not correct the material weaknesses in a timely manner, we will be unable to conclude that we maintain effective internal controls over financial reporting. Accordingly, there could continue to be a reasonable possibility that these deficiencies or others could result in a misstatement of our accounts or disclosures that would result in a material misstatement of our financial statements that would not be prevented or detected on a timely basis.

The process of designing and implementing internal control over financial reporting required to comply with Section 404 of the Sarbanes-Oxley Act will be time consuming, costly and complicated. If during the evaluation and testing process, we identify one or more other material weaknesses in our internal control over financial reporting or determine that existing material weaknesses have not been remediated, our management will be unable to assert that our internal control over financial reporting is effective. Even if our management concludes that our internal control over financial reporting is effective, our independent registered public accounting firm may conclude that there are material weaknesses with respect to our internal controls or the level at which our internal controls are documented, designed, implemented or reviewed. If we are unable to assert that our internal control over financial reporting is effective, or when required in the future, if our independent registered public accounting firm is unable to express an opinion as to the effectiveness of our internal control over financial reporting, investors may lose confidence in the accuracy and completeness of our financial reports, the market price of our common stock could be adversely affected and we could become

subject to litigation or investigations by the stock exchange on which our securities are listed, the SEC or other regulatory authorities, which could require additional financial and management resources.

We allow our clients to utilize application programming interfaces, or APIs, with our platform, which could result in outages or security breaches and negatively impact our business, financial condition and operating results.

The use of application programming interfaces, or APIs, by our clients has significantly increased in recent years. Our APIs allow clients to build their own media buying and data management interface by using our APIs to develop custom integration of their business with our platform. The increased use of APIs increases security and operational risks to our systems, including the risk for intrusion attacks, data theft, or denial of service attacks. Furthermore, while APIs allow clients greater ease and power in accessing our platform, they also increase the risk of overusing our systems, potentially causing outages. We have experienced system slowdowns due to client overuse of our systems through our APIs. While we have taken measures intended to decrease security and outage risks associated with the use of APIs, we cannot guarantee that such measures will be successful. Our failure to prevent outages or security breaches resulting from API use could result in government enforcement actions against us, claims for damages by consumers and other affected individuals, costs associated with investigation and remediation damage to our reputation and loss of goodwill, any of which could have a material adverse impact on our business, financial condition and operating results.

We may experience outages and disruptions of our platform if we fail to maintain adequate security and supporting infrastructure as we scale our platform, which may harm our reputation and negatively impact our business, financial condition and operating results.

As we grow our business, we expect to continue to invest in technology services and equipment, including data centers, network services and database technologies, as well as potentially increase our reliance on open source software. Without these improvements, our operations might suffer from unanticipated system disruptions, slow transaction processing, unreliable service levels, impaired quality or delays in reporting accurate information regarding transactions in our platform, any of which could negatively affect our reputation and ability to attract and retain clients. In addition, the expansion and improvement of our systems and infrastructure may require us to commit substantial financial, operational and technical resources, with no assurance our business will increase. If we fail to respond to technological change or to adequately maintain, expand, upgrade and develop our systems and infrastructure in a timely fashion, our growth prospects and results of operations could be adversely affected. The steps we take to increase the reliability, integrity and security of our platform as it scales are expensive and complex, and our execution could result in operational failures and increased vulnerability to cyber-attacks. Such cyber-attacks could include denial-of-service attacks impacting service availability (including the ability to deliver ads) and reliability, tricking company employees into releasing control of their systems to a hacker, or the introduction of computer viruses or malware into our systems with a view to steal confidential or proprietary data. Cyber-attacks of increasing sophistication may be difficult to detect and could result in the theft of our intellectual property and data from our platform. We are also vulnerable to unintentional errors or malicious actions by persons with authorized access to our systems that exceed the scope of their access rights, distribute data erroneously, or, unintentionally or intentionally, interfere with the intended operations of our platform. Moreover, we could be adversely impacted by outages and disruptions in the online platforms of our inventory and data suppliers, such as the real-time advertising exchanges. Outages and disruptions of our platform, including due to cyber-attacks, may harm our reputation and negatively impact our business, financial condition and results of operations.

Operational and performance issues with our platform, whether real or perceived, including a failure to respond to technological changes or to upgrade our technology systems, may adversely affect our business, financial condition and operating results.

We depend upon the sustained and uninterrupted performance of our platform to manage our inventory supply; bid on inventory for each campaign; collect, process and interpret data; and optimize campaign performance in real time and provide billing information to our financial systems. If our platform cannot scale to meet demand, if there are errors in our execution of any of these functions on our platform, or if we experience outages, then our business may be harmed. We may also face material delays in introducing new services, products and enhancements. If competitors introduce new products and services using new technologies or if new industry standards and practices emerge, our existing proprietary technology and systems may become obsolete.

Our platform is complex and multifaceted, and operational and performance issues could arise both from the platform itself and from outside factors. Errors, failures, vulnerabilities or bugs have been found in the past, and may in the future, be found. Our platform also relies on third-party technology and systems to perform properly, and our platform is often used in connection with computing environments utilizing different operating systems, system management software, equipment and networking configurations, which may cause errors in, or failures of, our platform or such other computing environments. Operational and performance issues with our platform could include the failure of our user interface, outages, errors during upgrades or patches, discrepancies in costs billed versus costs paid, unanticipated volume overwhelming our databases, server failure, or catastrophic events affecting one or more server farms. While we have built redundancies in our systems, full redundancies do not exist. Some failures will shut our platform down completely, others only partially. Partial failures, which we have experienced in the past, could result in unauthorized bidding, cessation of our ability to bid or deliver impressions or deletion of our reporting, in each case resulting in unanticipated financial obligations or impact.

Operational and performance issues with our platform could also result in negative publicity, damage to our brand and reputation, loss of or delay in market acceptance of our platform, increased costs or loss of revenue, loss of the ability to access our platform, loss of competitive position or claims by clients for losses sustained by them. Alleviating problems resulting from such issues could require significant expenditures of capital and other resources and could cause interruptions, delays or the cessation of our business, any of which may adversely affect our financial condition and operating results.

Legislation and regulation of online businesses, including privacy and data protection regimes, could create unexpected costs, subject us to enforcement actions for compliance failures, or cause us to change our platform or business model, which may have a material adverse effect on our business.

U.S. and foreign governments have enacted or are considering enacting legislation related to digital advertising and we expect to see an increase in, or changes to, legislation and regulation related to our industry, including the use of geo-location data to inform advertising, the collection and use of non-identifiable or identifiable Internet user data and unique device identifiers, such as IP address or mobile unique device identifiers, and other data protection and privacy-related regulation. Additionally, industry groups in the United States, such as the Digital Advertising Alliance, or DAA, and the Network Advertising Initiative, or NAI, and their international counterparts have self-regulatory guidelines to which we have agreed to adhere. Such legislation and regulation could cause us to incur unexpected compliance costs and adversely affect demand for our platform, or otherwise harm our business, results of operation and financial condition.

For instance, a wide variety of local, state, national and international laws and regulations apply to the collection, use, retention, protection, disclosure, transfer (including transfer across national

boundaries) and other processing of data collected from or about consumers and devices. While we have not collected data that is traditionally considered personal data, such as an individual's name, email address, address, phone numbers, social security numbers, or credit card numbers, we typically do collect and store IP addresses and other device identifiers, which are or may be considered personal data in some jurisdictions or otherwise may be the subject of legislation or regulation. Evolving definitions of what is considered personal data within the European Union and elsewhere, or personally identifying or identifiable information within the United States, as well as significant changes in the privacy regime in the European Union, have in the past and may cause us in the future to change our business practices, require significant changes to our backend configuration, increase operating costs, or limit our ability to operate or expand our business.

We take commercially reasonable measures to protect the security of information that we collect, use and disclose in the operation of our business, and to offer privacy protections with respect to such information, including conducting third-party audits of our privacy practices and review our privacy policy. Such measures, however, may not always be effective and may not identify data security or privacy related risks or inadequate or inappropriate practices we have used or adopted.

Additionally, as the advertising industry evolves, and new ways of collecting, combining and using data are created, governments may enact legislation that could result in our having to re-design features or functions of our platform, therefore incurring unexpected compliance costs. For example, the Federal Trade Commission, or the FTC, has examined, and likely will continue to examine, the privacy issues that arise as marketers track consumers across several devices, otherwise known as cross-device tracking. The FTC may promulgate regulations regarding cross-device tracking, may encourage legislation governing these practices, or may determine that it has sufficient enforcement under Section 5 of the Federal Trade Commission Act to investigate companies engaging in cross-device tracking.

While we contractually prohibit our clients and inventory and data suppliers from supplying personally identifiable information or other sensitive information to our system, we may inadvertently receive such information, which may result in us breaching privacy-related legislation or regulations. Additionally, we have contractual obligations to indemnify and hold harmless some of our clients and suppliers for the costs or consequences of our failure to comply with privacy-related legislation and regulations, which may be triggered by such inadvertent ingestion of personally identifiable information in our platform.

In addition to government regulation, the DAA and NAI, and other privacy advocates and industry groups, may propose new and different self-regulatory standards that either legally or contractually apply to us. We also expect that there will continue to be new proposed laws and regulations concerning privacy, data protection and information security, and we cannot yet determine the impact such future laws, regulations and standards may have on our business. Future laws, regulations, standards and other obligations, and changes in the interpretation of existing laws, regulations, standards and other obligations could impair our or our clients' ability to collect, use or disclose information relating to consumers, which could decrease demand for our platform, increase our costs and impair our ability to maintain and grow our client base and increase our revenue. New laws, amendments to or re-interpretations of existing laws and regulations, industry standards, contractual obligations and other obligations may require us to incur additional costs and restrict our business operations. Because the interpretation and application of laws, contractual obligations and other obligations relating to privacy and data protection are still uncertain, it is possible that these laws and other obligations may be interpreted and applied in a manner that is inconsistent with our existing data management practices or the features of our platform. If so, in addition to the possibility of fines, lawsuits and other claims, we could be required to fundamentally change our business activities and practices or modify our products, which could have an adverse effect on our business. We may be

unable to make such changes and modifications in a commercially reasonable manner or at all, and our ability to develop new products and features could be limited.

Data protection and privacy concerns are an important part of the programmatic advertising buying industry. Even the perception of privacy concerns, whether or not valid, may harm our reputation and inhibit use of our platform by current and future clients. For example, claims or adverse publicity could result from the perception of pharmaceuticals or medical advertisements targeting conditions. Our failure or perceived failure to comply with applicable laws and regulations could result in enforcement actions against us, including fines, imprisonment of our officers and public censure, claims for damages by consumers and other affected individuals, damage to our reputation and loss of goodwill, any of which could have a material adverse impact on our business, financial condition and operating results.

If the use of "third-party cookies" is rejected by Internet users, restricted or otherwise subject to unfavorable regulation, our performance may decline and we may lose advertisers and revenue.

Internet advertising relies on the use of "cookies," pixels and other similar technology, which are small text files placed on an Internet user's computer. To provide our platform, we utilize "third-party cookies," which are cookies owned and used by parties other than the owners of the website visited by the Internet user. Our cookies record non-personal information, such as when an Internet user views an ad, clicks on an ad or visits one of our advertiser's websites through a browser while the cookie is active. We use cookies to help us achieve our advertisers' campaign goals, to help us ensure that the same Internet user does not unintentionally see the same advertisement, to report aggregate information to our advertisers regarding the performance of their advertising campaigns and to detect and prevent fraudulent activity throughout our network of inventory. We also use data from cookies, which enable websites to collect information from users, to help our clients decide whether to bid on, and how to price, an opportunity to place an advertisement in a specific location, at a given time, in front of a particular Internet user. Without cookie data, our clients would bid on advertising without sufficient insight into activity that has taken place through an Internet user's browser. Consequently, lack of cookie data may compromise the ability to determine which inventory to purchase for a specific campaign, and undermine the effectiveness of our platform.

Cookies may be deleted or blocked by Internet users who do not want information to be collected about them. The most commonly used Internet browsers—Chrome, Firefox, Internet Explorer and Safari—allow Internet users to modify their browser settings to prevent cookies from being accepted by their browsers. Additionally, the Safari browser currently blocks third-party cookies by default and the browser provider Mozilla, which publishes the Firefox browser, has announced its intent to block third-party cookies by default in future versions of its browser. In addition, Internet users can also delete cookies from their computers at any time. Some Internet users also download free or paid ad blocking software that prevents third-party cookies from being stored on a user's computer. Additionally, the DAA, NAI and our company have certain opt-out mechanisms for users to opt out of the collection of their information via cookies. If more Internet users adopt these settings or delete their cookies more frequently than they currently do, or restrictions are imposed by advertisers and publishers, there are changes in technology or new developments in laws, regulations or industry standards around cookies, our business could be harmed.

In addition, in the EU, Directive 2009/136/EC, commonly referred to as the "Cookie Directive," directs EU member states to ensure that accessing information on an Internet user's computer, such as through a cookie, is allowed only if the Internet user has given his or her consent. In response, some member states have adopted and implemented, and may continue to adopt and implement, legislation that negatively impacts the use of cookies for online advertising. Limitations on the use or effectiveness of cookies, whether imposed by EU member state implementations of the Cookie Directive or otherwise, may impact the performance of our platform. We may be required to, or otherwise may

determine that it is advisable to, develop or obtain additional tools and technologies to compensate for the lack of cookie data. We may not be able to develop, implement or acquire additional tools that compensate for the lack of cookie data. Moreover, even if we are able to do so, such additional tools may be subject to further regulation, time consuming to develop or costly to obtain, and less effective than our current use of cookies.

Potential "Do Not Track" standards or government regulation could limit our access to the user data that informs the advertising campaigns we run and, as a result, undermine the effectiveness of our platform.

As the use of cookies has received ongoing media attention over the past several years, some government regulators and privacy advocates have suggested creating a "Do Not Track" standard that would allow Internet users to express a preference, independent of cookie settings in their browser, not to have their online browsing activities tracked. Similar standards are being set at device-level so that activities on mobile devices, including browsing and app uses, are not tracked. The FTC has issued a staff report criticizing the advertising industry's self-regulatory efforts as too slow and lacking adequate consumer protections, emphasizing a need for simplified notice, choice and transparency to the consumer regarding the collection, use and sharing of data, and suggested implementing a "Do Not Track" browser setting that allows consumers to choose whether or not to allow tracking of their online browsing activities. The major Internet browsers have implemented some version of a "Do Not Track" setting. Internet Explorer 10, for instance, includes a "Do Not Track" setting that is selected by default. The potential regulatory and self-regulatory landscape is inherently uncertain at this point in time, as there is no definition of tracking, no consensus regarding what message is conveyed by a "Do Not Track" setting and no industry standards regarding how to respond to a "Do Not Track" preference. The World Wide Web Consortium, or W3C, chartered a "Tracking Protection Working Group" in 2011 to convene a multi-stakeholder group of academics, thought leaders, companies, industry groups and consumer advocacy organizations, to create a voluntary "Do Not Track" standard for the World Wide Web. The group has yet to agree upon a standard and has considered disbanding due to uncertainty regarding the implementation of a "Do Not Track" standard. Despite the lack of consensus in this arena, the FTC has suggested that it will pursue legislation if the industry cannot agree upon a standard. If a "Do Not Track" browser setting is adopted by many Internet users or if a "Do Not Track" standard imposed by state or federal legislation, or agreed upon by standard setting groups, prohibits us from using non-personal data as we currently do, we may have to change our business practices, our clients may reduce their use of our platform, and our business, financial condition and operating results could be adversely affected.

Failure to comply with industry self-regulation could harm our brand, reputation and business.

We have committed to comply with the NAI's Code of Conduct and the DAA's Self-Regulatory Principles for Online Behavioral Advertising in the United States, as well as similar self-regulatory principles in Europe and Canada adopted by the local Digital Advertising Alliance. Our efforts to comply with these self-regulatory principles include offering Internet users notice and transparency when advertising is served to them based, in part, on browsing data recorded by cookies. We also offer Internet users the ability to opt out of receiving interest-based advertisements. If we make mistakes in our implementation of these principles, or if self-regulatory bodies expand these guidelines or government authorities issue different guidelines regarding Internet-based advertising, or our opt out mechanisms fail to work as designed, or if Internet users misunderstand our technology or our commitments with respect to these principles, we may, as a result, be subject to negative publicity, government investigation, government or private litigation, or investigation by self-regulatory bodies or other accountability groups. Any such action against us, or investigations, even if meritless, could be costly and time consuming, require us to change our business practices, cause us to divert management's attention and our resources and be damaging to our brand, reputation and business.

Our failure to meet content and inventory standards and provide services that our advertisers and inventory suppliers trust, could harm our brand and reputation and negatively impact our business, financial condition and operating results.

We do not provide or control either the content of the advertisements we serve or that of the websites providing the inventory. Advertisers provide the advertising content and inventory suppliers provide the inventory. Both advertisers and inventory suppliers are concerned about being associated with content they consider inappropriate, competitive or inconsistent with their brands, or illegal and they are hesitant to spend money without guaranteed brand security. Additionally, advertisers may seek to display advertising campaigns in jurisdictions that do not permit such advertising (for example, pharmaceutical advertising is not permitted in many countries). Consequently, our reputation depends in part on providing services that our advertisers and inventory suppliers trust, and we have contractual obligations to meet content and inventory standards. We contractually prohibit the misuse of our platform by agencies (and their advertiser clients) and inventory suppliers. Additionally, we use our proprietary technology and third-party services to, and we participate in industry co-ops that work to, detect malware and other content issues as well as click fraud (whether by humans or software known as "bots") and to block fraudulent inventory, including "tool bar" inventory, which is inventory that appears within an application and displaces any advertising that would otherwise be displayed on the website. Despite such efforts, our clients may inadvertently purchase inventory that proves to be unacceptable for their campaigns, in which case, we may not be able to recoup the amounts paid to inventory suppliers. Preventing and combating fraud is an industry-wide issue that requires constant vigilance, and we cannot guarantee that we will be fully successful in doing so. There are other means we could use, such as human review of content we serve, that some of our competitors undertake, but because our platform is self-service, and because such means are cost-intensive, we do not utilize all means available to decrease this risk. We may provide access to inventory that is objectionable to our advertisers or we may serve advertising that contains malware or objectionable content to our inventory suppliers, which could harm our or our clients' brand and reputation, and negatively impact our business, financial condition and operating results.

If we fail to offer sufficient client training and support, our business and reputation would suffer.

Because we offer a self-serve platform, client training and support is important for the successful marketing and continued use of our platform and for maintaining and increasing spend through our platform from existing and new clients. Providing this training and support requires that our platform operations personnel have specific domain knowledge and expertise, making it more difficult for us to hire qualified personnel and to scale up our support operations due to the extensive training required. The importance of high-quality client service will increase as we expand our business and pursue new clients. If we are not responsive and proactive regarding our clients' advertising needs, or do not provide effective support for our clients' advertising campaigns, our ability to retain our existing clients would suffer and our reputation with existing or potential clients would be harmed, which would negatively impact our business.

If the non-proprietary technology, software, products and services that we use are unavailable, have future terms we cannot agree to, or do not perform as we expect, our business, financial condition and operating results could be harmed.

We depend on various technology, software, products and services from third parties or available as open source, including for critical features and functionality of our platform, data centers and API technology, payment processing, payroll and other professional services. For example, in order for clients to target ads in ways they desire and otherwise optimize and verify campaigns, our platform must have access to data regarding Internet user behavior and reports with demographic information regarding Internet users. Identifying, negotiating, complying with and integrating with third-party terms

and technology are complex, costly and time-consuming matters. Failure by third-party providers to maintain, support or secure their technology either generally or for our accounts specifically, or downtime, errors or defects in their products or services, could materially and adversely impact our platform, our administrative obligations or other areas of our business. Having to replace any third-party providers or their technology, products or services could result in outages or difficulties in our ability to provide our services. For example, we rely upon third-party co-location providers for our data centers, and we are dependent on these third parties to provide continuous power, cooling, Internet connectivity and physical and technological security for our servers. In the event that these third-party providers experience any interruption in operations or cease business for any reason, or if we are unable to agree on satisfactory terms for continued hosting relationships, we would be forced to enter into a relationship with other service providers or assume some hosting responsibilities ourselves. In addition, even a disruption as brief as a few minutes could have a negative impact on marketplace activities and could therefore result in a loss of revenue. If we are unsuccessful in establishing or maintaining our relationships with our third-party providers or otherwise need to replace them, internal resources may need to be diverted and our business, financial condition and operating results could be harmed.

We face potential liability and harm to our business based on the human factor of inputting information into our platform.

Campaigns are set up using several variables available to our clients on our platform. While our platform includes several checks and balances, it is possible for human error to result in significant over-spending. The system requires a daily cap at the ad group level. We also provide for the client to input daily and overall caps at the advertising inventory campaign level at their discretion. Additionally, we set a credit limit for each user so that they cannot spend beyond the level of credit risk we are willing to accept. Despite these protections, the ability for overspend exists. For example, campaigns which last for a period of time can be set to pace evenly or as quickly as possible. If a client with a high credit limit enters into the wrong daily cap with a campaign set to a rapid pace, it is possible for a campaign to accidently go significantly over budget. While our client contracts state that clients are responsible for media purchased through our platform, we are ultimately responsible for paying the inventory providers and we may be unable to collect for such issues.

International expansion subjects us to additional costs and risks that can adversely affect our business, financial condition and operating results.

International expansion subjects us to many challenges associated with supporting a rapidly growing business across a multitude of cultures, customs, monetary, legal and regulatory systems and commercial infrastructures. We have a limited operating history outside of the United States, and our ability to manage our business and conduct our operations internationally requires considerable attention and resources.

We currently have sales personnel in the United Kingdom, Australia, Germany, South Korea, Singapore, Japan, and Hong Kong, and we anticipate expanding our international operations in the future, including in China, Indonesia and potentially other countries that score low on the Corruption Perceptions Index, or CPI, of the Transparency International. Our sales organization outside the United States is substantially smaller than our sales organization in the United States. To the extent we are unable to effectively engage with non-U.S. advertising agencies or international divisions of U.S. agencies due to our limited sales force capacity, we may be unable to effectively grow in international markets.

Approximately 7% of our gross spend in 2015 was derived from outside of the United States. Our international operations subject us to a variety of additional risks, including:

We may incur significant operating expenses as a result of our international expansion, and it may not be successful. Our international business also subjects us to the impact of global and regional recessions and economic and political instability, differing regulatory requirements, costs and difficulties in managing a distributed workforce, potentially adverse tax consequences in the United States and abroad and restrictions on the repatriation of funds to the United States. In addition, advertising markets outside of the United States are not as developed as those within the United States, and we may be unable to grow our business sufficiently. Our failure to manage these risks and challenges successfully could materially and adversely affect our business, financial condition and operating results.

Exposure to foreign currency exchange rate fluctuations could negatively impact our operating results.

While the majority of the transactions through our platform are denominated in U.S. dollars, we have transacted in foreign currencies for both inventory and for payments by clients from use of our platform, including the Canadian dollar, British Pound, the Euro, Singapore Dollar, Indonesian Rupiah, Japanese Yen and Australian Dollar. Given our anticipated international growth, we expect the number of transactions in foreign currencies to continue to grow in the future. While we do require a fee from our clients that pay in non-U.S. currency, this fee may not always cover foreign currency exchange rate fluctuations. We currently have a program to hedge exposure to foreign currency fluctuations. However, the use of hedging instruments may not be available for all currencies, or may not always offset losses resulting from foreign currency exchange rate fluctuations. Moreover, the use of hedging instruments can itself result in losses if we are unable to structure effective hedges with such instruments.

Future acquisitions, strategic investments or alliances could disrupt our business and harm our business, financial condition and operating results.

We may in the future explore potential acquisitions of companies or technologies, strategic investments, or alliances to strengthen our business. However, we have limited experience in acquiring and integrating businesses, products and technologies. Even if we identify an appropriate acquisition candidate, we may not be successful in negotiating the terms or financing of the acquisition, and our due diligence may fail to identify all of the problems, liabilities or other shortcomings or challenges of an acquired business, product or technology, including issues related to intellectual property, product quality or architecture, regulatory compliance practices, revenue recognition or other accounting practices or employee or client issues. Acquisitions involve numerous risks, any of which could harm our business, including:

Failure to appropriately mitigate these risks or other issues related to such strategic investments and acquisitions could result in reducing or completely eliminating any anticipated benefits of transactions, and harm our business generally. Future acquisitions could also result in dilutive issuances of our equity securities, the incurrence of debt, contingent liabilities, amortization expenses or the impairment of goodwill, any of which could harm our business, financial condition and operating results.

We may not be able to secure additional financing on favorable terms, or at all, to meet our future capital needs, which may in turn impair our growth.

We intend to continue to grow our business, which will require additional capital to develop new features or enhance our platform, improve our operating infrastructure, finance working capital requirements or acquire complementary businesses and technologies. Accordingly, we may need to engage in additional equity or debt financings to secure additional capital. If we raise additional funds through future issuances of equity or convertible debt securities, our existing stockholders could suffer significant dilution, and any new equity securities we issue could have rights, preferences and privileges superior to those of holders of our common stock. Any debt financing that we secure in the future

could involve restrictive covenants relating to our capital raising activities and other financial and operational matters, which may make it more difficult for us to obtain additional capital and to pursue business opportunities. If we are unable to secure additional funding on favorable terms, or at all, when we require it, our ability to continue to grow our business to react to market conditions could be impaired and our business may be harmed.

Our credit facility contains operating and financial covenants that restrict our business and financing activities.

Our credit facility contains restrictions that limit our flexibility in operating our business. In March 2016, we entered into a loan and security agreement with a syndicate led by Citibank, N.A., which we refer to as our credit facility. Subject to certain customary conditions, we have access to borrow up to $125.0 million aggregate principal amount of revolver borrowings. The amount of borrowing availability under the credit facility is based on our accounts receivable balance, reduced by certain reserves. At the entry into the credit facility, we incurred $50.8 million in revolver borrowings, which were used to repay our 2015 loan facility. Our credit facility also contains various covenants that limit our ability to engage in specified types of transactions. Subject to limited exceptions, these covenants limit our ability to, among other things:

In addition, our credit facility contains a fixed charge coverage ratio which requires us to maintain a certain ratio of our earnings to principal and interest payable under the credit facility in a given period. Our obligations under the credit facility are collateralized by a pledge of substantially all of our assets, including accounts receivable, deposit accounts, intellectual property, investment property and equipment. The covenants in our credit facility may limit our ability to take actions and, in the event that we breach one or more covenants, our lenders may choose to declare an event of default and require that we immediately repay all amounts outstanding, terminate the commitment to extend further credit and foreclose on the collateral granted to them to collateralize such indebtedness, which includes our intellectual property. In addition, if we fail to meet the required covenants, we will not have access to further draw-downs under the credit facility.

Our future success depends on the continuing efforts of our key employees, including Jeff T. Green and David R. Pickles, and our ability to attract, hire, retain and motivate highly skilled employees in the future.

Our future success depends on the continuing efforts of our executive officers and other key employees, including our two founders, Jeff T. Green, our chief executive officer, and David R. Pickles, our chief technology officer. We rely on the leadership, knowledge and experience that our executive officers provide. They foster our corporate culture, which has been instrumental to our ability to attract and retain new talent. We also rely on employees in our product development, support and sales teams to attract and keep key clients.

The market for talent in our key areas of operations, including California, is intensely competitive, which could increase our costs to attract and retain talented employees. As a result, we may incur significant costs to attract and retain employees, including significant expenditures related to salaries and benefits and compensation expenses related to equity awards, and we may lose new employees to our competitors or other companies before we realize the benefit of our investment in recruiting and training them. New employees often require significant training and, in many cases, take significant time before they achieve full productivity. Our account managers, for instance, need to be trained quickly on the features of our platform since failure to offer high-quality support may adversely affect our relationships with our clients. Technology companies like ours compete to attract the best talent. Additionally, we have little experience with recruiting in geographies outside of the United States, and may face additional challenges in attracting and retaining international employees.

Employee turnover, including changes in our management team, could disrupt our business. None of our founders or other key employees has an employment agreement for a specific term, and any of our employees may terminate his or her employment with us at any time. The loss of one or more of our executive officers, especially our two founders, or our inability to attract and retain highly skilled employees could have an adverse effect on our business, financial condition and operating results.

Most members of our management team have limited or no experience managing a publicly-traded company, interacting with public company investors, and complying with the increasingly complex laws, rules and regulations that govern public companies. There are significant obligations we will now be subject to relating to reporting, procedures and internal controls, and our management team may not successfully or efficiently manage our transition to being a public company. These new obligations and scrutiny will require significant attention from our management and could divert their attention away from the day-to-day management of our business, which could adversely affect our business, financial condition and operating results.

If we do not effectively grow and train our sales and support teams, we may be unable to add new clients or increase sales to our existing clients and our business will be adversely affected.

We are substantially dependent on our sales and support teams to obtain new clients and to increase spend by our existing clients. We believe that there is significant competition for sales personnel with the skills and technical knowledge that we require. Our ability to achieve revenue growth will depend, in large part, on our success in recruiting, training, integrating and retaining sufficient numbers of sales personnel to support our growth. Due to the complexity of our platform, new hires require significant training and it may take significant time before they achieve full productivity. Our recent and planned hires may not become productive as quickly as we expect, and we may be unable to hire or retain sufficient numbers of qualified individuals in the markets where we do business or plan to do business. If we are unable to hire and train sufficient numbers of effective sales personnel, or the sales personnel are not successful in obtaining new clients or increasing our existing clients' spend with us, our business will be adversely affected.

Our corporate culture has contributed to our success and, if we are unable to maintain it as we grow, our business, operating results and financial condition could be harmed.

We have experienced and may continue to experience rapid expansion of our employee ranks. We had 296 employees in the United States and 91 employees outside the United States as of June 30, 2016, compared to 181 employees in the United States and 46 employees outside the United States as of June 30, 2015. We believe our corporate culture has been a key element of our success. However, as our organization grows, it may be difficult to maintain our culture, which could reduce our ability to innovate and operate effectively. The failure to maintain the key aspects of our culture as our

organization grows could result in decreased employee satisfaction, increased difficulty in attracting top talent, increased turnover and could compromise the quality of our client service, all of which are important to our success and to the effective execution of our business strategy. In the event we are unable to maintain our corporate culture as we grow to scale, our business, operating results and financial condition could be harmed.

Our proprietary rights may be difficult to enforce, which could enable others to copy or use aspects of our technology without compensating us, thereby eroding our competitive advantages and harming our business.

We rely upon a combination of trade secrets, third-party confidentiality and non-disclosure agreements, additional contractual restrictions on disclosure and use, and trademark, copyright and other intellectual property laws to establish and protect our proprietary rights. These laws, procedures and restrictions provide only limited protection. We currently have "The Trade Desk, Inc." registered as a trademark or pending registration in the United States and certain foreign countries. We also rely on copyright laws to protect computer programs related to our platform and our proprietary technologies, although to date we have not registered for statutory copyright protection. We have registered numerous Internet domain names in the United States related to our business in order to protect our proprietary interests. We endeavor to enter into agreements with our employees and contractors in order to limit access to and disclosure of our proprietary information, as well as to clarify rights to intellectual property associated with our business. Protecting our intellectual property is a challenge, especially after our employees or our contractors end their relationship with us, and, in some cases, decide to work for our competitors. Our contracts with our employees and contractors that relate to intellectual property issues generally restrict the use of our confidential information solely in connection with our services, and strictly prohibit reverse-engineering. However, reverse engineering our software or the theft or misuse of our proprietary information could occur by employees or contractors who have access to our technology. Enforceability of the non-compete agreements that we have in place is not guaranteed, and contractual restrictions could be breached without discovery or adequate remedies.

Policing unauthorized use of our technology is difficult. In addition, the laws of some foreign countries may not be as protective of intellectual property rights as those of the United States, and mechanisms for enforcement of our proprietary rights in such countries may be inadequate. If we are unable to protect our proprietary rights (including in particular, the proprietary aspects of our platform) we may find ourselves at a competitive disadvantage to others who have not incurred the same level of expense, time and effort to create and protect their intellectual property.

We may be sued by third parties for alleged infringement of their proprietary rights, which would result in additional expense and potential damages.

There is significant patent and other intellectual property development activity in the digital advertising industry. Third-party intellectual property rights may cover significant aspects of our technologies or business methods or block us from expanding our offerings. Our success depends on the continual development of our platform. From time to time, we may receive claims from third parties that our platform and underlying technology infringe or violate such third parties' intellectual property rights. To the extent we gain greater public recognition, we may face a higher risk of being the subject of intellectual property claims. The cost of defending against such claims, whether or not the claims have merit, is significant, regardless of whether we are successful in our defense, and could divert the attention of management, technical personnel and other employees from our business operations. Litigation regarding intellectual property rights is inherently uncertain due to the complex issues involved, and we may not be successful in defending ourselves in such matters. Additionally, we may be obligated to indemnify our clients or inventory and data suppliers in connection with any such litigation. If we are found to infringe these rights, we could potentially be required to cease utilizing portions of our platform. We may also be required to develop alternative non-infringing technology,

which could require significant time and expense. Alternatively, we could be required to pay royalty payments, either as a one-time fee or ongoing, as well as damages for past use that was deemed to be infringing. If we cannot license or develop technology for any allegedly infringing aspect of our business, we would be forced to limit our service and may be unable to compete effectively. Any of these results could harm our business.

We face potential liability and harm to our business based on the nature of our business and the content on our platform.

Advertising often results in litigation relating to copyright or trademark infringement, public performance royalties or other claims based on the nature and content of advertising that is distributed through our platform. Though we contractually require agencies to represent to us that they have the rights necessary to serve advertisements through our platform, we do not independently verify whether we are permitted to deliver, or review the content of, such advertisements. If any of these representations are untrue, we may be exposed to potential liability and our reputation may be damaged. While our clients are typically obligated to indemnify us, such indemnification may not fully cover us, or we may not be able to collect. In addition to settlement costs, we may be responsible for our own litigations costs, which can be extensive.

We are subject to anti-bribery, anti-corruption and similar laws and non-compliance with such laws can subject us to criminal penalties or significant fines and harm our business and reputation.

We are subject to anti-bribery and similar laws, such as the U.S. Foreign Corrupt Practices Act of 1977, as amended, or the FCPA, the U.S. domestic bribery statute contained in 18 U.S.C. § 201, the USA PATRIOT Act, U.S. Travel Act, the U.K. Bribery Act 2010 and Proceeds of Crime Act 2002, and possibly other anti-corruption, anti-bribery and anti-money laundering laws in countries in which we conduct activities. Anti-corruption laws have been enforced with great rigor in recent years and are interpreted broadly and prohibit companies and their employees and their agents from making or offering improper payments or other benefits to government officials and others in the private sector. As we increase our international sales and business, particularly in countries with a low score on the CPI by Transparency International, and increase our use of third parties such as sales agents, distributors, resellers or consultants, our risks under these laws will increase. We adopt appropriate policies and procedures and conduct training, but cannot guarantee that improprieties will not occur. Noncompliance with these laws could subject us to investigations, sanctions, settlements, prosecution, other enforcement actions, disgorgement of profits, significant fines, damages, other civil and criminal penalties or injunctions, suspension and/or debarment from contracting with specified persons, the loss of export privileges, reputational harm, adverse media coverage, and other collateral consequences. Any investigations, actions and/or sanctions could have a material negative impact on our business, operating results and financial condition.

We are subject to governmental economic sanctions requirements and export and import controls that could impair our ability to compete in international markets or subject us to liability if we are not in compliance with applicable laws.

As a U.S. company, we are subject to U.S. export control and economic sanctions laws and regulations, and we are required to export our technology and services in compliance with those laws and regulations, including the U.S. Export Administration Regulations and economic embargo and trade sanction programs administered by the Treasury Department's Office of Foreign Assets Control. U.S. economic sanctions and export control laws and regulations prohibit the shipment of specified products and services to countries, governments and persons targeted by U.S. sanctions. While we are currently taking precautions to prevent doing any business, directly or indirectly, with countries, governments and persons targeted by U.S. sanctions and to ensure that our technology and services are

not exported or used by countries, governments and persons targeted by U.S. sanctions, such measures may be circumvented. There can be no assurance that we will be in compliance with U.S. export control or economic sanctions laws and regulations in the future. Any such violation could result in significant criminal or civil fines, penalties or other sanctions and repercussions, including reputational harm that could materially adversely impact our business.

Furthermore, if we export our technology, the exports may require authorizations, including a license, a license exception or other appropriate government authorization. Complying with export control and sanctions regulations may be time-consuming and may result in the delay or loss of opportunities.

In addition, various countries regulate the import of encryption technology, including the imposition of import permitting and licensing requirements, and have enacted laws that could limit our ability to offer our platform or could limit our clients' ability to use our platform in those countries. Changes in our platform or future changes in export and import regulations may create delays in the introduction of our platform in international markets or prevent our clients with international operations from deploying our platform globally. Any change in export or import regulations, economic sanctions or related legislation, or change in the countries, governments, persons, or technologies targeted by such regulations, could result in decreased use of our platform by, or in our decreased ability to export our technology and services to, existing or potential clients with international operations. Any decreased use of our platform or limitation on our ability to export our platform would likely adversely affect our business operations and financial results.

The market growth forecasts included in this prospectus may prove to be inaccurate and, even if the market in which we compete achieves forecasted growth, we cannot assure you our business will grow at similar rates, if at all.

Market growth forecasts are subject to significant uncertainty and are based on assumptions and estimates which may not prove to be accurate. The forecasts in this prospectus relating to expected growth in the digital advertising and real-time buying markets may prove to be inaccurate. Even if these markets experience the forecasted growth, we may not grow our business at similar rates, or at all. Our growth is subject to many factors, including our success in implementing our business strategy, which is subject to many risks and uncertainties.

The U.S. and non-U.S. tax laws applicable to our business activities are subject to interpretation. We are subject to audit by the Internal Revenue Service and by taxing authorities of the state, local and foreign jurisdictions in which we operate. Our tax obligations are based in part on our corporate operating structure, including the manner in which we develop, value, and use our intellectual property, the jurisdictions in which we operate, how tax authorities assess revenue-based taxes such as sales and use taxes, the scope of our international operations and the value we ascribe to our intercompany transactions. Taxing authorities may challenge our tax positions and methodologies for valuing developed technology or intercompany arrangements, as well as our positions regarding the collection of sales and use taxes and the jurisdictions in which we are subject to taxes, which could expose us to additional taxes. Any adverse outcomes of such challenges to our tax positions could result in additional taxes for prior periods, interest and penalties, as well as higher future taxes. In addition, our future tax expense could increase as a result of changes in tax laws, regulations or accounting principles, or as a result of earning income in jurisdictions that have higher tax rates. An increase in our tax expense could have a negative effect on our financial position and results of operations. Moreover, the determination of our provision for income taxes and other tax liabilities requires significant estimates and judgment by management, and the tax treatment of certain transactions is uncertain. Although we believe we will make reasonable estimates and judgments, the ultimate

outcome of any particular issue may differ from the amounts previously recorded in our financial statements and any such occurrence could materially affect our financial position and results of operations.

The market price of our Class A common stock may be volatile or may decline regardless of our operating performance, and you may not be able to resell your shares at or above the initial public offering price.

The market price of equity securities of technology companies has historically experienced high levels of volatility. If you purchase shares of our Class A common stock in our initial public offering, you may not be able to resell those shares at or above the initial public offering price. Following the completion of our initial public offering, the market price of our Class A common stock may fluctuate significantly in response to numerous factors, some of which are beyond our control and may not be related to our operating performance, including:

In addition, if the stock market for technology companies, or the stock market generally, experiences a loss of investor confidence, the trading price of our Class A common stock could decline for reasons unrelated to our business, operating results or financial condition. Stock prices of many technology companies have fluctuated in a manner unrelated or disproportionate to the operating performance of those companies. The trading price of our common stock might also decline in reaction to events that affect other companies in our industry even if these events do not directly affect us. In the past, stockholders have filed securities class action litigation following periods of market volatility. If we were to become involved in securities litigation, it could subject us to substantial costs, divert resources and the attention of management from our business, and adversely affect our business.

Sales of substantial blocks of our common stock into the public market after this offering, including when "lock-up" or "market standoff" periods end, or the perception that such sales might occur, could cause the market price of our Class A common stock to decline and may make it more difficult for you to sell your Class A common stock at a time and price that you deem appropriate. Based on the total number of outstanding shares of our common stock as of June 30, 2016, upon completion of this offering, we will have 38,228,554 shares of common stock outstanding (assuming no exercise of the underwriters' option to purchase additional shares). All of the shares of Class A common stock sold in this offering will be freely tradable without restrictions or further registration under the Securities Act of 1933, as amended, or the Securities Act, except for any shares held by our "affiliates" as defined in Rule 144 under the Securities Act.

Subject to exceptions described under the caption "Underwriting," we, all of our directors and officers, the selling stockholders and substantially all of the other holders of our capital stock and securities convertible into, or exchangeable for, our capital stock have agreed not to offer, sell or agree to sell, directly or indirectly, any shares of common stock without the permission of Citigroup for a period of 180 days from the date of this prospectus. Participants in our Directed Share Program that are not directors, officers or employees of us have also entered into lock-up agreements with the underwriters under which they have agreed, subject to specific exceptions, not to sell any of our stock for 30 days following the date of this prospectus without the prior written consent of Citigroup. When the applicable lock-up period expires, we, our directors and officers and locked-up stockholders will be able to sell shares into the public market.

The underwriters may, in their sole discretion, permit our directors and officers and locked-up stockholders to sell shares prior to the expiration of the restrictive provisions contained in the "lock-up" agreements with the underwriters. In addition, we may, in our sole discretion, permit our employees and current stockholders who are subject to market standoff agreements or arrangements with us and who are not subject to a lock-up agreement with the underwriters to sell shares prior to the expiration of the restrictive provisions contained in those market standoff agreements or arrangements.

Based on shares outstanding as of June 30, 2016, holders of up to approximately 32,557,387 shares, or 85%, of our common stock after this offering (assuming no exercise of the underwriters' option to purchase additional shares), will have rights to require us to file registration statements covering the sale of such shares or to include such shares in registration statements that we may file for ourselves or other stockholders. We also intend to register the offer and sale of all shares of common stock that we may issue under our equity compensation plans.

The market price of our Class A common stock could decline as a result of the sale of substantial blocks of our common stock into the public market after this offering, or the perception that such sales might occur.

Insiders will continue to have substantial control over our company after this offering, including as a result of the dual class structure of our common stock, which could limit your ability to influence the outcome of key decisions, including a change of control.

Our Class B common stock has ten votes per share, and our Class A common stock, which is the stock we are offering in our initial public offering, has one vote per share. Stockholders who hold shares of Class B common stock, including our executive officers, employees, and directors and their affiliates, will together hold approximately 99% of the voting power of our outstanding capital stock following our initial public offering (assuming no exercise of the underwriters' option to purchase

additional shares). Because of the ten-to-one voting ratio between our Class B and Class A common stock, the holders of our Class B common stock collectively will continue to control a majority of the combined voting power of our common stock and therefore be able to control all matters submitted to our stockholders for approval so long as the shares of Class B common stock represent at least 9.1% of all outstanding shares of our Class A and Class B common stock. This concentrated control will limit or preclude your ability to influence corporate matters for the foreseeable future. These stockholders will be able to influence or control matters requiring approval by our stockholders, including the election of directors and the approval of mergers, acquisitions or other extraordinary transactions. Their interests may differ from yours and they may vote in a manner that is adverse to your interests. This ownership concentration may deter, delay or prevent a change of control of our company, deprive our stockholders of an opportunity to receive a premium for their common stock as part of a sale of our company and may ultimately affect the market price of our common stock.

Future transfers by holders of Class B common stock will generally result in those shares converting to Class A common stock, subject to limited exceptions, such as transfers effected for estate planning or charitable purposes. The conversion of Class B common stock to Class A common stock will have the effect, over time, of increasing the relative voting power of those holders of Class B common stock who retain their shares in the long term. For a description of the dual class structure, see the section captioned "Description of Capital Stock—Anti-Takeover Provisions."

We cannot assure you that an active trading market for our Class A common stock will develop or, if developed, that any such market will be sustained, and we cannot predict the market price at which our Class A common stock will trade in the future.

We cannot assure you that an active trading market for our Class A common stock will develop or, if developed, that any such market will be sustained. The initial public offering price of our Class A common stock will be determined by negotiations with the underwriters and may not bear any relationship to the market price at which our Class A common stock will trade after this offering or to any other established criteria of the value of our business. We cannot predict the market price at which our Class A common stock will trade in the future.

We have broad discretion in the use of net proceeds that we receive in this offering and we may not use them effectively.

We currently intend to use a significant portion of the net proceeds from this offering for general corporate purposes, including working capital, funding the expansion of our business, including expanding our sales and marketing programs, and making investments in our technology and development teams to support the development of new applications and features for, and enhancements of, our platform. We may also use a portion of the net proceeds from this offering for the acquisition of, or investment in, technologies or businesses that complement our business, although we have no present commitments or agreements to enter into any such acquisitions or make any investments. Our management will have broad discretion in the application of the net proceeds, including possible acquisitions of, or investments in, businesses or technologies. The failure by our management to apply these funds effectively could harm our business, financial condition and operating results.

The requirements of being a public company may strain our resources, divert our management's attention and affect our ability to attract and retain qualified board members.

As a public company, we will be subject to the reporting requirements of the Exchange Act, and will be required to comply with the applicable requirements of the Sarbanes-Oxley Act and the Dodd-Frank Wall Street Reform and Consumer Protection Act, the listing requirements of NASDAQ, and other applicable securities rules and regulations. Compliance with these rules and regulations will

increase our legal and financial compliance costs, make some activities more difficult, time-consuming or costly and increase demand on our systems and resources. Among other things, the Exchange Act requires that we file annual, quarterly and current reports with respect to our business and operating results and maintain effective disclosure controls and procedures and internal controls over financial reporting. Significant resources and management oversight will be required to maintain and, if required, improve our disclosure controls and procedures and internal controls over financial reporting to meet this standard. As a result, management's attention may be diverted from other business concerns, which could harm our business and operating results. Although we have already hired additional employees to comply with these requirements, we may need to hire even more employees in the future, which will increase our costs and expenses.

We also expect that being a public company and these new rules and regulations will make it more expensive for us to obtain director and officer liability insurance, and we may be required to accept reduced coverage or incur substantially higher costs to obtain coverage. These factors could also make it more difficult for us to attract and retain qualified members of our board of directors, particularly to serve on our audit committee and compensation committee, and qualified executive officers.

If we fail to maintain or implement effective internal controls, we may not be able to report financial results accurately or on a timely basis, or to detect fraud, which could have a material adverse effect on our business and the per share price of our common stock.

The Sarbanes-Oxley Act requires, among other things, that we maintain effective disclosure controls and procedures, and internal control over financial reporting. We are continuing to develop and refine our disclosure controls and other procedures that are designed to ensure that information required to be disclosed by us in the reports that we will file with the SEC is recorded, processed, summarized and reported within the time periods specified in SEC rules and forms. We are also continuing to improve our internal control over financial reporting. We have expended, and anticipate that we will continue to expend, significant resources in order to maintain and improve the effectiveness of our disclosure controls and procedures and internal control over financial reporting.

Our current controls and any new controls that we develop may become inadequate because of changes in conditions in our business, including increased complexity resulting from our international expansion. Further, weaknesses in our disclosure controls or our internal control over financial reporting may be discovered in the future. Any failure to develop or maintain effective controls, or any difficulties encountered in their implementation or improvement, could harm our operating results or cause us to fail to meet our reporting obligations and may result in a restatement of our financial statements for prior periods. Any failure to implement and maintain effective internal control over financial reporting could also adversely affect the results of management reports and independent registered public accounting firm audits of our internal control over financial reporting that we will eventually be required to include in our periodic reports that will be filed with the SEC. Ineffective disclosure controls and procedures, and internal control over financial reporting could also cause investors to lose confidence in our reported financial and other information, which would likely have a negative effect on the market price of our common stock. In addition, if we are unable to continue to meet these requirements, we may not be able to remain listed on NASDAQ.

We are not currently required to comply with the SEC rules that implement Section 404 of the Sarbanes-Oxley Act, and are therefore not required to make a formal assessment of the effectiveness of our internal control over financial reporting for that purpose. Upon becoming a public company, we will be required to provide an annual management report on the effectiveness of our internal control over financial reporting commencing with our second annual report on Form 10-K. Our independent registered public accounting firm is not required to audit the effectiveness of our internal control over financial reporting until after we are no longer an "emerging growth company," as defined in the JOBS Act. At such time, our independent registered public accounting firm may issue a report that is adverse

in the event it is not satisfied with the level at which our internal control over financial reporting is documented, designed or operating.

Any failure to maintain effective disclosure controls and internal control over financial reporting could have a material and adverse effect on our business and operating results, and cause a decline in the market price of our common stock.

We are an "emerging growth company" and we cannot be certain if the reduced disclosure requirements applicable to emerging growth companies will make our common stock less attractive to investors.

For so long as we remain an "emerging growth company" as defined in the JOBS Act, we may take advantage of exemptions from various requirements that are applicable to public companies that are not "emerging growth companies," including not being required to comply with the independent auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act, reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. We may take advantage of these exemptions for so long as we are an "emerging growth company," which could be as long as five full fiscal years following the completion of this offering. Investors may find our common stock less attractive because we rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock, and our stock price may be more volatile and may decline.

In addition, Section 107 of the JOBS Act also provides that an "emerging growth company" can take advantage of an extended transition period for complying with new or revised accounting standards. However, we chose to "opt out" of such extended transition period, and as a result, we will comply with new or revised accounting standards on the relevant dates adoption of such standards is required for non-emerging growth companies. Our decision to opt out of the extended transition period for complying with new or revised accounting standards is irrevocable.

If securities or industry analysts do not publish research or reports about our business, or publish inaccurate or unfavorable research reports about our business, our share price and trading volume could decline.

The trading market for our Class A common stock will partially depend on the research and reports that securities or industry analysts publish about us or our business. We do not have any control over these analysts. If one or more of the analysts who cover us should downgrade our shares or change their opinion of our business prospects, our share price would likely decline. If one or more of these analysts ceases coverage of our company or fails to regularly publish reports on us, we could lose visibility in the financial markets, which could cause our share price or trading volume to decline.

Our charter documents and Delaware law could discourage takeover attempts and other corporate governance changes.

Our certificate of incorporation and bylaws that will be in effect upon completion of this offering, each of which we will submit to our pre-IPO stockholders for approval in connection with this offering, contain provisions that could delay or prevent a change in control of our company. These provisions could also make it difficult for stockholders to elect directors that are not nominated by the current members of our board of directors or take other corporate actions, including effecting changes in our management. These provisions include the following provisions:

In addition, as a Delaware corporation, we are subject to Section 203 of the Delaware General Corporation Law. These provisions may prohibit large stockholders, in particular those owning 15% or more of our outstanding voting stock, from merging or combining with us for a period of time.

Our amended and restated certificate of incorporation will provide that the Court of Chancery of the State of Delaware will be the exclusive forum for substantially all disputes between us and our stockholders, which could limit our stockholders' ability to choose other forums for disputes with us or our directors, officers or employees.

Our amended and restated certificate of incorporation will provide that the Court of Chancery of the State of Delaware shall be the sole and exclusive forum for: (1) any derivative action or proceeding brought on our behalf; (2) any action asserting a claim of breach of a fiduciary duty by any of our directors, officers, employees or our stockholders owed to us or our stockholders; (3) any action asserting a claim arising pursuant to any provision of the Delaware General Corporation Law, our amended and restated certificate of incorporation or our amended and restated bylaws, or as to which the Delaware General Corporation Law confers jurisdiction on the Court of Chancery of the State of Delaware; or (4) any action asserting a claim governed by the internal affairs doctrine. This choice of forum provision may limit a stockholder's ability to bring a claim in other judicial forums for disputes with us or our directors, officers or other employees, which may discourage lawsuits against us and our directors, officers and other employees in jurisdictions other than Delaware. Alternatively, if a court were to find the choice of forum provision contained in our amended and restated certificate of incorporation to be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving such action in other jurisdictions, which could have a material adverse effect our business, financial condition or results of operations.

This prospectus contains forward-looking statements within the meaning of the federal securities laws, which statements involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or our future financial or operating performance. In some cases, you can identify forward-looking statements because they contain words such as "may," "will," "should," "expects," "plans," "anticipates," "could," "intends," "target," "projects," "contemplates," "believes," "estimates," "predicts," "potential" or "continue" or the negative of these words or other similar terms or expressions that concern our expectations, strategy, plans or intentions. Forward-looking statements contained in this prospectus include, but are not limited to, statements about:

We have based the forward-looking statements contained in this prospectus primarily on our current expectations and projections about future events and trends that we believe may affect our business, financial condition, results of operations, prospects, business strategy and financial needs. The outcome of the events described in these forward-looking statements is subject to risks, uncertainties,

assumptions and other factors described in the section captioned "Risk Factors" and elsewhere in this prospectus. These risks are not exhaustive. Other sections of this prospectus include additional factors that could adversely impact our business and financial performance. Moreover, we operate in a very competitive and rapidly changing environment. New risks and uncertainties emerge from time to time and it is not possible for us to predict all risks and uncertainties that could have an impact on the forward-looking statements contained in this prospectus. We cannot assure you that the results, events and circumstances reflected in the forward-looking statements will be achieved or occur, and actual results, events or circumstances could differ materially from those described in the forward-looking statements.

In addition, statements that "we believe" and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

You should read this prospectus and the documents that we reference in this prospectus and have filed as exhibits to the registration statement of which this prospectus forms a part with the understanding that our actual future results, levels of activity, performance and achievements may be materially different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

The forward-looking statements made in this prospectus relate only to events as of the date on which such statements are made. We undertake no obligation to update any forward-looking statements after the date of this prospectus or to conform such statements to actual results or revised expectations, except as required by law.

Unless otherwise indicated, information contained in this prospectus concerning our industry and the markets in which we operate, including our general expectations and market position, market opportunity and market size, is based on reports from various sources, including those set forth below, assumptions that we have made based on such data and our knowledge of the market for our platform. Because this information involves a number of assumptions and limitations, you are cautioned not to give undue weight to such information. The content of the below sources, except to the extent specifically set forth in this prospectus, does not constitute a portion of this prospectus and is not incorporated herein.

In addition, projections, assumptions, and estimates of our future performance and the future performance of the industry in which we operate are necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in the section captioned "Risk Factors" and elsewhere in this prospectus. These and other factors could cause results to differ materially from those expressed in the estimates made by third parties and by us.

We estimate that the net proceeds to us from the sale of shares of our Class A common stock in this offering will be approximately $69.8 million, based upon the assumed initial public offering price of $17.00 per share, which is the midpoint of the estimated offering price range set forth on the cover page of this prospectus, and after deducting underwriting discounts and commissions and estimated offering expenses payable by us. If the underwriters exercise their option to purchase additional shares in full, we estimate that the net proceeds to be received by us and/or the selling stockholders will be approximately $80.8 million, after deducting underwriting discounts, commissions and estimated offering expenses payable by us. We will not receive any proceeds from the sale of shares of our Class A common stock by the selling stockholders.

A $1.00 increase (decrease) in the assumed initial public offering price of $17.00 per share would increase (decrease) the net proceeds that we receive from this offering by approximately $4.3 million, assuming that the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us. Similarly, each increase (decrease) of 1.0 million in the number of shares offered by us would increase (decrease) the net proceeds that we receive from this offering by approximately $15.8 million, assuming that the assumed initial public offering price remains the same and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us.

On March 30, 2016, we paid off all remaining principal and interest due under our previous 2015 credit facility. Pursuant to the terms of this facility, upon the occurrence of our initial public offering, we remain obligated to pay the lenders a fee of $750,000. We intend to satisfy this obligation with the net proceeds to us from this offering.

We will have broad discretion over the uses of the net proceeds from this offering and investors will be relying on the judgement of our management regarding the application of the net proceeds from this offering. Pending the use of proceeds from this offering as described above, we plan to invest the net proceeds that we receive in this offering in short-term and long-term interest-bearing obligations, including government- and investment-grade debt securities and money market funds.

We have never declared or paid cash dividends on our capital stock. We currently intend to retain any future earnings for use in the operation of our business and do not intend to declare or pay any cash dividends in the foreseeable future. Any further determination to pay dividends on our capital stock will be at the discretion of our board of directors, subject to applicable laws, and will depend on our financial condition, results of operations, capital requirements, general business conditions, and other factors that our board of directors considers relevant. In addition, the terms of our credit facility contains restrictions on our ability to pay dividends. For further information regarding our credit facility, see the sections captioned "Management's Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources—Credit Facility," "Risk Factors—Risks Related to Our Business and Industry—Our credit facility contains operating and financial covenants that restrict our business and financing activities," and the notes to our audited consolidated financial statements in this prospectus.

The following table sets forth cash and our capitalization as of June 30, 2016 on:

	As of June 30, 2016

	Actual			Pro Forma			Pro Forma As Adjusted⁽¹⁾
	(in thousands, except share and per share data)
Cash	$	37,610		$	37,610		$	108,392



Long-term debt, net of current portion	$	56,623		$	56,623		$	56,623
Convertible preferred stock warrant liabilities		7,943			—			—
Convertible preferred stock, $0.000001 par value; 80,021,127 shares authorized, 66,235,964 shares issued and outstanding actual; no shares authorized, issued and outstanding, pro forma and pro forma as adjusted		83,241			—			—
Stockholders' equity (deficit):
Preferred stock, $0.000001 par value; no shares authorized, issued and outstanding, actual; 100,000,000 shares authorized, no shares issued and outstanding, pro forma and pro forma as adjusted		—			—			—
Common stock, $0.000001 par value, 142,000,000 shares authorized, 11,035,426 shares issued and outstanding, actual; no shares authorized, issued and outstanding, pro forma and pro forma as adjusted		—			—			—
Class A common stock, $0.000001 par value; no shares authorized, issued and outstanding, actual; 1,000,000,000 shares authorized, 100 shares issued and outstanding, pro forma; 1,000,000,000 shares authorized, 4,666,767 shares issued and outstanding, pro forma as adjusted		—			—			—
Class B common stock, $0.000001 par value; no shares authorized, issued and outstanding, actual; 95,000,000 shares authorized, 33,561,787 shares issued and outstanding, pro forma; 95,000,000 shares authorized, 33,561,787 shares issued and outstanding, pro forma as adjusted		—			—			—
Additional paid-in capital		452			91,636			161,416
Accumulated deficit		(28,742	)		(28,742	)		(29,492	)

Total stockholders' equity (deficit)		(28,290	)		62,894			131,924

Total capitalization	$	119,517		$	119,517		$	188,547

⁽¹⁾: A $1.00 increase (decrease) in the assumed initial public offering price of our Class A common stock of $17.00 per share, which is the midpoint of the estimated offering price range set forth on the cover page of this prospectus, would increase (decrease) the pro forma as adjusted amount of cash, and cash equivalents, additional paid-in capital, total stockholders' equity and total capitalization by approximately $4.3 million, assuming that the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and after deducting underwriting discounts and commissions and estimated offering expenses payable by us. We may also increase or decrease the number of shares we are offering. Each increase (decrease) of 1.0 million in the number of shares offered by us would increase (decrease) the pro forma as adjusted amount of cash, and cash equivalents, additional paid-in capital, total stockholders' equity and total capitalization by approximately $15.8 million, assuming that the assumed initial public offering price remains the same and after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

The pro forma as adjusted column in the table above excludes the following, in each case as of June 30, 2016:

If you invest in our Class A common stock in this offering, your interest will be immediately diluted to the extent of the difference between the initial public offering price per share of our Class A common stock in this offering and the net tangible book value per share of our common stock after this offering. As of June 30, 2016, we had a historical net tangible book value of $51.6 million, or $4.67 per share of common stock. Our net tangible book value represents total tangible assets less total liabilities, all divided by the number of shares of common stock outstanding on such date. Our pro forma net tangible book value at June 30, 2016, before giving effect to this offering, was $59.5 million, or $1.77 per share of our common stock. Pro forma net tangible book value, before the issuance and sale of shares in this offering, gives effect to:

After giving effect to the sale of 4,666,667 shares of Class A common stock in this offering at an assumed initial public offering price of $17.00 per share, the midpoint of the price range set forth on the cover page of this prospectus, and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us and the payment by us of the $750,000 fee that we are obligated to pay to the lenders of our previous 2015 credit facility in connection with this offering, our pro forma as adjusted net tangible book value at June 30, 2016 would have been approximately $130.8 million, or $3.42 per share. This represents an immediate increase in pro forma as adjusted net tangible book value of $1.65 per share to existing stockholders and an immediate dilution of $13.58 per share to new investors. The following table illustrates this per share dilution:

A $1.00 increase (decrease) in the assumed initial public offering price of our Class A common stock of $17.00 per share, the midpoint of the price range set forth on the cover page of this prospectus, would increase (decrease), our pro forma as adjusted net tangible book value per share after this offering by $0.11, and would increase (decrease) dilution per share to new investors in this offering by $0.89, assuming that the number of shares offered by us, as set forth on the cover page of

this prospectus, remains the same and after deducting underwriting discounts and commissions and estimated offering expenses payable by us. Similarly, each increase (decrease) of 1.0 million shares in the number of shares offered by us would increase (decrease) our pro forma as adjusted net tangible book value per share after this offering by approximately $0.32 per share and decrease (increase) the dilution to new investors by approximately $0.32 per share, assuming that the assumed initial public offering price remains the same, and after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

If the underwriters fully exercise their option to purchase additional shares and all such shares are sold by the Company, pro forma as adjusted net tangible book value after this offering would increase to approximately $0.22 per share, and there would be an immediate dilution of approximately $0.22 per share to investors in this offering.

To the extent that outstanding options with an exercise price per share that is less than the pro forma as adjusted net tangible book value per share, before giving effect to the issuance and sale of shares in this offering, are exercised, new investors will experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

The following table shows, as of June 30, 2016, on a pro forma as adjusted basis, after giving effect to the pro forma adjustments described above, the number of shares of common stock purchased from us, the total consideration paid to us and the average price paid per share by existing stockholders and by new investors purchasing Class A common stock in this offering at an assumed initial public offering price of $17.00 per share, before deducting underwriting discounts and commissions and estimated offering expenses payable by us (in thousands, except per share amounts and percentages):

Sales by the selling stockholders in this offering will cause the number of shares held by existing stockholders to be reduced to 32,861,887 shares, or 86% of the total number of shares of our common stock outstanding after this offering, and will increase the number of shares held by new investors to 5,366,667 shares, or 14% of the total number of shares of our common stock outstanding after this offering, assuming that the underwriters exercise their option to purchase additional shares in full and that the selling stockholders sell all of such shares to the underwriters.

The above table and discussion include no shares of Class A common stock and 33,561,887 shares of Class B common stock (in each case, on an as-converted basis) outstanding as of June 30, 2016 and exclude, in each case as of June 30, 2016:

The selected consolidated statements of operations data for the years ended December 31, 2014 and 2015 and the selected consolidated balance sheet data as of December 31, 2014 and 2015 are derived from our audited consolidated financial statements included elsewhere in this prospectus. The selected consolidated statements of operations data for the six months ended June 30, 2015 and 2016 and the selected consolidated balance sheet data as of June 30, 2016 are derived from our unaudited condensed consolidated financial statements included elsewhere in this prospectus. Our unaudited interim condensed consolidated financial statements were prepared on a basis consistent with that used to prepare our audited annual consolidated financial statements and include, in the opinion of management, all adjustments, consisting of normal recurring items, necessary for the fair statement of the condensed consolidated financial statements.

You should read this data together with our audited consolidated financial statements and related notes, as well as the information under the caption "Management's Discussion and Analysis of Financial Condition and Results of Operations" in this prospectus. Our historical results are not necessarily indicative of our future results, and results for any interim period below are not necessarily indicative of results for the full year.

	Year Ended December 31,					Six Months Ended June 30,

	2014			2015		2015		2016
	(in thousands, except per share data)
Consolidated Statements of Operations Data:
Revenue	$	44,548		$	113,836	$	42,410	$	77,560
Operating expenses⁽¹⁾:
Platform operations		12,559			22,967		9,642		16,195
Sales and marketing		14,590			26,794		11,692		19,682
Technology and development		7,250			12,819		5,096		10,402
General and administrative		9,385			13,276		5,177		12,851

Total operating expenses		43,784			75,856		31,607		59,130

Income from operations		764			37,980		10,803		18,430
Total other expense, net		1,707			8,125		1,436		6,524

Income (loss) before income taxes		(943	)		29,855		9,367		11,906
Provision for (benefit from) income taxes		(948	)		13,926		3,693		5,348

Net income	$	5		$	15,929	$	5,674	$	6,558



Net income (loss) attributable to common stockholders⁽²⁾	$	—		$	8,764	$	5,470	$	(40,651	)



Earnings (loss) per share—basic⁽²⁾:	$	—		$	0.85	$	0.54	$	(3.74	)



Earnings (loss) per share—diluted⁽²⁾	$	—		$	0.39	$	0.15	$	(3.74	)



Pro forma earnings per share—basic⁽²⁾				$	0.68			$	0.34



Pro forma earnings per share—diluted⁽²⁾				$	0.60			$	0.30



Non-GAAP Financial and Operating Data:
Adjusted EBITDA⁽³⁾	$	5,683		$	39,159	$	11,105	$	20,073



Gross spend⁽⁴⁾	$	211,266		$	552,325	$	200,013	$	404,815



Gross billings⁽⁵⁾	$	201,804		$	529,975	$	192,990	$	389,245

	As of December 31,

	As of December 31,					As of June 30, 2016
	2014			2015		As of June 30, 2016
	(in thousands)
Consolidated Balance Sheet Data:
Cash	$	17,315		$	4,047	$	37,610
Accounts receivable, net		78,364			191,943		236,737
Total assets		102,238			210,231		294,951
Accounts payable		58,293			108,461		164,296
Long-term debt, net of current portion		16,493			45,918		56,623
Total liabilities		80,372			171,885		240,000
Convertible preferred stock		27,997			24,204		83,241
Total stockholders' equity (deficit)		(6,131	)		14,142		(28,290	)

Our use of Adjusted EBITDA has limitations as an analytical tool, and you should not consider it in isolation or as a substitute for analysis of our financial results as reported under GAAP. Some of these limitations are as follows:

•: although depreciation and amortization expense are non-cash charges, the assets being depreciated and amortized may have to be replaced in the future, and Adjusted EBITDA does not reflect cash capital expenditure requirements for such replacements or for new capital expenditure requirements;
•: Adjusted EBITDA does not reflect: (a) changes in, or cash requirements for, our working capital needs; (b) the potentially dilutive impact of stock-based compensation; or (c) tax payments that may represent a reduction in cash available to us; and
•: other companies, including companies in our industry, may calculate Adjusted EBITDA or similarly titled measures differently, which reduces its usefulness as a comparative measure.

Because of these and other limitations, you should consider Adjusted EBITDA along with other GAAP-based financial performance measures, including various cash flow metrics, net income and our GAAP financial results.

⁽⁴⁾: Gross spend includes the value of a client's purchases through the platform plus our platform fee, which is a percentage of a client's purchases through the platform. We review gross spend for internal management purposes to assess market share and scale and to plan for optimal levels of support for our clients. Some companies in our industry report revenue on a gross basis or use similar metrics, so tracking our gross spend allows us to compare our results to the results of those companies. Gross spend does not represent our revenue reported on a GAAP basis. Our gross spend is influenced by the volume and characteristics of bids for advertising inventory won through our platform. We expect our revenue as a percentage of gross spend, which is sometimes referred to as take rate, to fluctuate due to the types of services and features selected by our clients through our platform and certain volume discounts. We track gross spend based on the location of our office servicing the respective clients. Other companies, including companies in our industry, may calculate gross spend or similarly titled measures differently, which reduces its usefulness as a comparative measure.
⁽⁵⁾: Gross billings represents the amount we invoice our clients, net of allowances. As some of our clients have payment relationships directly with advertising inventory suppliers for the amount of advertising inventory the clients purchase through our platform, we do not invoice these clients for this spend, and we only invoice such clients for the data, other services and our platform fee. Accordingly, gross billings are less than gross spend and represent gross spend, less platform discounts and less the value of advertising and data that our clients purchase directly from publishers through our platform. We report revenue on a net basis which represents gross billings net of amounts we pay suppliers for the cost of advertising inventory, data and add-on features. We expect our revenue as a percentage of gross billings to fluctuate due to the types of services and features selected by our clients through our platform and certain volume discounts. We review gross billings for internal management purposes to adequately plan for our working capital needs and monitor collection risk. We track gross billings based on the billing address of the client. In many cases, international clients are serviced from our United States offices resulting in gross billings exceeding gross spend for international clients.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
AND RESULTS OF OPERATIONS

You should read the following discussion and analysis of our financial condition and results of operations together with the consolidated financial statements and the related notes to the consolidated financial statements included elsewhere in this prospectus. In addition to historical financial information, the following discussion contains forward-looking statements that reflect our plans, estimates, beliefs and expectations, and involve risks and uncertainties. Factors that could cause or contribute to these differences include those discussed below and elsewhere in this prospectus, particularly under the captions "Risk Factors" and "Special Note Regarding Forward-Looking Statements."

We are a technology company that empowers ad buyers. We provide a self-service platform that enables our clients to purchase and manage data-driven digital advertising campaigns using their own teams. Our platform allows clients to manage integrated advertising campaigns across various advertising formats, including display, video and social, and on a multitude of devices, including computers, mobile devices and connected TV, an approach that we refer to as omnichannel.

Our company was founded in 2009 by two pioneers of programmatic advertising buying who were motivated to allow buyers of advertising to precisely target audiences with the most relevant and highest performing ads. We commercially launched our platform in May 2011. Since launch, we have also extended our platform to address additional advertising formats. In 2011, approximately 100% of gross spend on our platform was for display advertising compared to 57% in 2015, with the remainder derived from mobile, video and social. We had 137 clients at the beginning of 2014 and we added 121 additional clients (net of any lost clients) during that year. We had 258 clients at the beginning of 2015 and we added 131 additional clients (net of any lost clients) during that year.

Our clients are the advertising agencies and other service providers for advertisers. By aligning our business with buyers we avoid inherent conflicts of interest that exist when serving both the buy and sell-side, which we believe helps us build trust with our clients. We provide our platform through a self-service, browser based user interface and also enable clients to customize and build their own features and reports on our platform through our application programming interfaces. After adding a client through our sales team or an in-bound request, we teach clients how to use our platform to design and execute advertising campaigns independently.

We generate revenue by charging our clients a platform fee based on a percentage of a client's total spend on advertising, data and other features through our platform, the total of which we refer to as gross spend. We enter into ongoing master service agreements with our clients as opposed to episodic insertion orders. To further align our interests with those of our clients, we do not buy advertising inventory in order to resell it to our clients for a profit.

The growing digitization of media and fragmentation of audiences has increased the complexity of advertising, and thereby increased the need for automation in ad buying, which we provide on our platform. In order to grow, we will need to continue to develop our platform's programmatic capabilities and advertising inventory. We believe that key opportunities include our ongoing expansion into video and television ad inventory and continuing development of our data usage and advertising targeting capabilities.

We believe that our revenue as a percentage of gross spend, which is sometimes referred to as take rate, may fluctuate from period to period due to a number of factors, such as changes in the proportion of spend represented by our larger customers with the lowest platform fees, our clients' use of platform features and volume discounts. We expect that our revenue as a percentage of gross spend will fluctuate and may decrease in the future, especially as we introduce and as our clients select new

platform features, expand our omnichannel capabilities, extend our reach to TV inventory and add additional clients whose businesses may have different underlying business models.

We believe that growth of the programmatic advertising market is important for our ability to grow our business. Adoption of programmatic advertising by advertisers allows us to acquire new clients and grow revenue from existing clients. Although our clients include some of the largest advertising agencies in the world, we believe there is significant room for us to expand further within these clients and gain a larger amount of their advertising spend through our platform. We also believe that the industry trends noted above will lead to advertisers adopting programmatic advertising through platforms such as ours.

Similarly, the adoption of programmatic advertising by inventory owners and content providers allows us to expand the volume and type of advertising inventory that we present to our clients. For example, we have expanded our native advertising offerings through our recent integrations with supply-side partners.

We plan to invest for long-term growth. We anticipate that our operating expenses will increase significantly in the foreseeable future as we invest in platform operations and technology and development to enhance our product features, including programmatic buying of television ad inventory, and in sales and marketing to acquire new clients and reinforce our relationships with existing clients. In addition, we expect to continue making investments in our infrastructure, including our information technology, financial and administrative systems and controls, to support our operations.

In addition, we believe the markets outside of the United States offer an opportunity for growth, and we intend to make additional investments in sales and marketing and product development to expand in these markets, including China, where we are making significant investments in launching our platform and growing our team. Gross spend on our platform outside the United States was $17 million in 2014 and $36 million in 2015.

We believe that these investments will contribute to our long-term growth, although they may negatively impact profitability in the near term.

Our business model has allowed us to grow significantly and achieve profitability. Our revenue was $44.5 million in 2014 and $113.8 million in 2015, representing a year over year increase of 156%. Our net income was $5,000 in 2014 and $15.9 million in 2015, and our Adjusted EBITDA was $5.7 million in 2014 and $39.2 million in 2015. Our revenue was $42.4 million for the six months ended June 30, 2015 and $77.6 million for the six months ended June 30, 2016, representing a period over period increase of 83%. Our net income was $5.7 million for the six months ended June 30, 2015 and $6.6 million for the six months ended June 30, 2016, and our Adjusted EBITDA was $11.1 million for the six months ended June 30, 2015 and $20.1 million for the six months ended June 30, 2016. Adjusted EBITDA is a non-GAAP financial measure. For information on how we compute Adjusted EBITDA, and a reconciliation of Adjusted EBITDA to net income on a GAAP basis, see footnote 3 in the section captioned "Selected Consolidated Financial Data."

Our recent growth has been driven by expanding our share of spend by our existing clients and adding new clients. Our clients include some of the largest advertising agencies in the world and we believe there is significant room for us to expand further within these clients. As a result, future revenue growth depends upon our ability to retain our existing clients and to gain a larger amount of their advertising spend through our platform.

In order to analyze the contribution to the growth of our business driven by the increase in gross spend from pre-existing clients, we measure annual gross spend for the set of clients, or cohort, that commenced spending on our platform in a specific year relative to subsequent periods. As illustrated in the following chart, the gross spend from each of our cohorts has increased over subsequent periods. Annual gross spend represents the value of a client's purchases through the platform plus our platform fee, which is a percentage of a client's purchases, through the platform, for each year. We believe that the trends reflected above are illustrative of the value of our client base; however, over time we will likely lose clients from each cohort, clients may spend less on our platform and the growth rate of gross spend may change. Any such change could have a significant negative impact on gross spend and operating results.

We enable the purchase of advertising inventory in a wide variety of formats. Although display advertising represented 57% of our gross spend in 2015, non-display advertising such as mobile, video and social are significant and increasing components of our gross spend. Non-display gross spend increased from approximately $66 million in 2014 to $237 million in 2015 and from $78 million for the first half of 2015 to $198 million for the first half of 2016. Our future growth will depend on our ability to maintain and grow the inventory of, and spend on, other channels. In addition, we believe that our ability to integrate and offer television and digital radio advertising inventory for purchase through our platform, and in particular our ability to manage the increased costs that will accompany these purchases, will impact the future growth of our business.

Our operating results and prospects will be impacted by the overall adoption of programmatic advertising by inventory owners and content providers, as well as advertisers and the agencies and service providers that represent them. Programmatic advertising has grown rapidly in recent years, and any acceleration, or slowing, of this growth would affect our operating and financial performance. In addition, even if the programmatic advertising market continues to grow at its current rate, our ability to position ourselves within the market will impact the future growth of our business.

We have recently increased our focus on markets outside the United States to serve the global needs of our clients. We believe that the global opportunity for programmatic advertising is significant, and should continue to expand as publishers and advertisers outside the United States seek to adopt the benefits that programmatic advertising provides. To capitalize on this opportunity, we intend to continue to invest to grow our presence internationally, including in China and Indonesia, where we have not historically operated to date. Our growth and the success of our initiatives in newer markets will depend on the continued adoption of our platform by our existing clients, as well as new clients, in these markets.

In the advertising industry, companies commonly experience seasonal fluctuations in revenue. For example, many advertisers allocate the largest portion of their budgets to the fourth quarter of the calendar year in order to coincide with increased holiday purchasing. Historically, the fourth quarter of the year reflects our highest level of advertising activity and the first quarter reflects the lowest level of such activity. We expect our revenue to continue to fluctuate based on seasonal factors that affect the advertising industry as a whole.

We have one primary business activity and operate in one operating and reportable segment.

We generate revenue from clients who enter into agreements with us to use our platform to purchase advertising inventory, data and other add-on features.

We report revenue on a net basis which represents gross billings net of amounts we pay suppliers for the cost of advertising inventory, data and add-on features. Our accounts receivable are recorded at the amount of gross billings to clients, net of allowances, for the amounts we are responsible to collect, and our accounts payable are recorded at the amount payable to suppliers. Accordingly, both accounts receivable and accounts payable appear large in relation to revenue reported on a net basis.

See "Critical Accounting Policies and Estimates—Revenue Recognition" for a description of our revenue recognition policies.

Platform Operations. Platform operations expense consists of expenses related to hosting our platform and providing support to our clients. Platform operations expense includes hosting costs, personnel costs, amortization of capitalized software costs for the development of our platform and allocated overhead. Personnel costs included in platform operations include salaries, bonuses, stock-based compensation, and employee benefit costs, and are primarily attributable to personnel who provide our clients with support using our platform and the network operations group that supports our platform. We capitalize certain costs associated with the development of our platform and amortize these costs in platform operations over their estimated useful lives. We allocate overhead such as information technology infrastructure, rent and occupancy charges based on headcount. Many of the expenses included in platform operations do not increase or decrease proportionately with increases or decreases in our revenue. We expect platform operations expenses to increase in absolute dollars in future periods as we continue to experience increased volumes of transactions through our platform and hire additional personnel to support our clients.

Sales and Marketing. Sales and marketing expense consists primarily of personnel costs, including salaries, bonuses, stock-based compensation, employee benefits costs and commission costs for our sales and marketing personnel. Sales and marketing expense also includes costs for market development programs, advertising, promotional and other marketing activities, and allocated overhead. We allocate overhead such as information technology infrastructure, rent and occupancy charges based on headcount. Commissions costs are expensed as incurred.

Our sales organization focuses on marketing our platform to increase its adoption by existing and new clients. We are also focused on expanding our international business by growing our sales teams in countries in which we currently operate, as well as establishing a presence in additional countries. As a result, we expect sales and marketing expenses to increase in absolute dollars in future periods. Sales and marketing expense as a percentage of revenue may fluctuate from period to period based on revenue levels and the timing of our investments in our sales and marketing functions as these investments may vary in scope and scale over periods and are impacted by the revenue seasonality in our industry and business.

Technology and Development. Our technology and development expense consists primarily of personnel costs, including salaries, bonuses, stock-based compensation and employee benefits costs, third party consultant costs associated with the ongoing development and maintenance of our platform, amortization of capitalized third party software used in the development of our platform and allocated overhead. We allocate overhead such as information technology infrastructure, rent and occupancy charges based on headcount. Technology and development costs are expensed as incurred, except to the extent that such costs are associated with software development that qualifies for capitalization, which are then recorded as capitalized software development costs included in other assets, non-current on our consolidated balance sheet. We amortize capitalized software development costs relating to our platform to platform operations expense.

We believe that continued investment in our platform is critical to attaining our strategic objectives and long-term growth. We therefore expect technology and development expense to increase as we continue to invest in the development of our platform to support additional features and functions, increase the number of advertising and data inventory suppliers and ramp up the volume of advertising spending on our platform. Our development efforts also include additional platform functionality to support our international expansion. We also intend to invest in technology to further automate our business processes.

General and Administrative. Our general and administrative expense consists primarily of personnel costs, including salaries, bonuses, stock-based compensation, and employee benefits costs associated with our executive, finance, legal, human resources, compliance, and other administrative personnel, as well as accounting and legal professional services fees, bad debt expense and allocated overhead. We allocate overhead such as information technology infrastructure, rent and occupancy charges based on headcount.

We expect to continue to invest in corporate infrastructure and incur additional expenses associated with the transition to and operation as a public company, including increased legal and accounting costs, investor relations costs, higher insurance premiums and compliance costs associated with developing the requisite infrastructure required for internal controls. As a result, we expect general and administrative expenses to increase in absolute dollars in future periods.

Interest Expense. Interest expense is mainly related to our debt, which carries a variable interest rate.

Change in Fair Value of Convertible Preferred Stock Warrant Liabilities. As of June 30, 2016, we had two outstanding warrants to purchase shares of our convertible preferred stock. These convertible preferred stock warrants are subject to re-measurement at each balance sheet date, and any change in fair value is recognized as a component of other expense, net. In connection with the closing of this offering, the warrants will convert into warrants to purchase shares of common stock. We will no longer be required to re-measure the value of any converted common stock warrants after this offering, and therefore, no further charges or credits related to such warrants will be made to other expense, net.

Foreign Currency Exchange Loss, Net. Foreign currency exchange loss, net consists primarily of gains and losses on foreign currency transactions. We have foreign currency exposure related to our accounts receivable and, to a much lesser extent, accounts payable that are denominated in currencies other than the U.S. Dollar, principally the Canadian Dollar, British Pound, the Euro, Singapore Dollar, Indonesian Rupiah, Japanese Yen and Australian Dollar.

The provision for (benefit from) income taxes consists primarily of federal, state, and foreign income taxes. Our income tax provision may be significantly affected by changes to our estimates for tax in jurisdictions in which we operate and other estimates utilized in determining the global effective tax rate. Actual results may also differ from our estimates based on changes in economic conditions. Such changes could have a substantial impact on the income tax provision. We reevaluate the judgments surrounding our estimates and make adjustments, as appropriate, each reporting period.

Our effective tax rate differs from the U.S. federal statutory income tax rate due to state taxes, fair value adjustments associated with our warrant liabilities, federal and foreign tax rate differences, research and development tax credits, non-deductible stock-based compensation and adjustments to our valuation allowance.

Realization of our deferred tax assets is dependent primarily on the generation of future taxable income. In considering the need for a valuation allowance, we consider our historical, as well as future, projected taxable income along with other objectively verifiable evidence. Objectively verifiable evidence includes our realization of tax attributes, assessment of tax credits and utilization of net operating loss carryforwards during the year.

In 2014, we released all of our valuation allowance previously established against our U.S. net deferred tax assets of $2.2 million. Our decision to release the valuation allowance on our U.S. deferred tax assets was due to, among other reasons, our three-year cumulative pre-tax income adjusted for permanent items realized in U.S. jurisdictions and significant forecasted U.S. taxable income.

The following tables set forth our consolidated results of operations and our consolidated results of operations as a percentage of revenue for the periods presented:

	Year Ended December 31,					Six Months Ended June 30,

	2014			2015		2015		2016
	(in thousands)
Revenue	$	44,548		$	113,836	$	42,410	$	77,560
Operating expenses:
Platform operations		12,559			22,967		9,642		16,195
Sales and marketing		14,590			26,794		11,692		19,682
Technology and development		7,250			12,819		5,096		10,402
General and administrative		9,385			13,276		5,177		12,851

Total operating expenses		43,784			75,856		31,607		59,130

Income from operations		764			37,980		10,803		18,430
Total other expense, net		1,707			8,125		1,436		6,524

Income (loss) before income taxes		(943	)		29,855		9,367		11,906
Provision for (benefit from) income taxes		(948	)		13,926		3,693		5,348

Net income	$	5		$	15,929	$	5,674	$	6,558

	Year Ended December 31,						Six Months Ended June 30,

	2014			2015			2015			2016
	*(as a percentage of revenue)**
Revenue		100	%		100	%		100	%		100	%
Operating expenses:
Platform operations		28			20			23			21
Sales and marketing		33			24			28			25
Technology and development		16			11			12			13
General and administrative		21			12			12			17

Total operating expenses		98			67			75			76

Income from operations		2			33			25			24
Total other expense, net		4			7			3			8

Income (loss) before income taxes		(2	)		26			22			15
Provision for (benefit from) income taxes		(2	)		12			9			7

Net income		—			14	%		13	%		8	%

The increase in revenue was primarily due to a 102% increase in gross spend on our platform. Gross spend on our platform by existing clients added on or before June 30, 2015 increased by 81% in the aggregate during the six months ended June 30, 2016 over the six months ended June 30, 2015, and these existing clients represented 88% of the total gross spend during the six months ended June 30, 2016. During the six months ended June 30, 2015, 54% of existing clients added on or before June 30, 2014 increased their gross spend on our platform and their average increase in gross spend was approximately $0.8 million. During the six months ended June 30, 2016, 53% of existing clients added on or before June 30, 2015 increased their gross spend on our platform and their average increase in gross spend was approximately $1.2 million. Revenue as a percentage of gross spend in the aggregate may fluctuate from period to period based on our client mix and the extent to which clients utilize our platform's features.

The increase in platform operations expense was primarily due to an increase in hosting costs of $4.5 million and an increase in personnel costs of $1.6 million. The increase in hosting costs was primarily attributable to supporting the increased use of our platform by our clients. The increase in personnel costs was primarily due to an increase in headcount for our client support team.

The increase in sales and marketing expense was primarily due to an increase in personnel costs of $4.1 million and an increase in marketing expenses of $3.0 million. The increase in personnel costs was primarily due to an increase in sales and marketing headcount in order to support our sales efforts and to continue to develop and maintain relationships with our clients. The increase in marketing expenses was mainly related to our participation in industry events, tradeshows and related public relations activities.

The increase in technology and development expense was primarily due to an increase in personnel costs of $3.6 million and an increase in facilities costs of $1.0 million. The increase in personnel costs was primarily due to an increase in headcount, which reflects our continued hiring of engineers to

maintain and support our technology and development efforts. The increase in facilities costs was due to additional lease costs for premises to support our higher headcount.

The increase in general and administrative expense was primarily due to an increase in personnel costs of $3.2 million, an increase in professional services fees of $2.6 million, and an increase in contractor and temporary staff costs of $1.2 million. The increase in personnel costs, professional services fees, and contractor and temporary staff costs was primarily related to finance and legal services to support our growth and for preparation of an initial public offering.

The increase in the fair value of our convertible preferred stock warrant liabilities was primarily due to an increase in the valuation of our preferred stock. The increase in interest expense was primarily attributable to an increase in our debt borrowings and the write-off of deferred debt issuance costs upon extinguishment of our prior debt facility.

Our effective income tax rate for the six months ended June 30, 2015 and 2016 was 39.4% and 44.9%, respectively. The increase in the effective income tax rate for the six months ended June 30, 2016 as compared to the corresponding period in 2015 was primary due to higher non-deductible preferred stock warrant expense.

The increase in revenue was primarily due to a 161% increase in gross spend on our platform. Gross spend on our platform by existing clients added prior to 2015 increased by 135% in the aggregate in 2015, and these existing clients represented 88% of the total gross spend in 2015. In 2014, 57% of existing clients added prior to 2014 increased their gross spend on our platform and their average increase in gross spend was approximately $1.0 million. In 2015, 59% of existing clients added prior to 2015 increased their gross spend on our platform and their average increase in gross spend was approximately $2.0 million. Revenue as a percentage of gross spend in the aggregate may fluctuate from period to period based on our client mix and the extent to which clients utilize our platform's features.

Platform operations expense in 2015 increased primarily due to increases of $5.7 million in hosting costs and $3.3 million in personnel costs. The increase in hosting costs was primarily attributable to supporting the increased use of our platform by our clients. The increase in personnel costs was primarily due to an increase in headcount for our client support team.

The increase in sales and marketing expense in 2015 was primarily due to increases of $9.0 million in personnel costs and $2.5 million in marketing expenses. The increase in personnel costs was primarily due to an increase in sales and marketing headcount in order to support our sales efforts and to continue to develop and maintain relationships with our clients. The increase in marketing expenses was mainly related to our participation in industry events, tradeshows and related public relations activities.

The increase in technology and development expense in 2015 was primarily due to an increase in personnel costs of $5.6 million which was partially offset by a decrease in stock-based compensation expense of $0.8 million primarily associated with the repurchase of common stock from our founders concurrent with our Series B preferred stock financing in February 2014. The increase in personnel costs was primarily due to an increase in headcount, which reflects our continued hiring of engineers to maintain and support our technology and development efforts. The increase in personnel costs was also partially offset by the amount of software development costs that are capitalized, which were $0.8 million in 2014 and $1.8 million in 2015. The capitalized software development costs were primarily attributable to the development of features and additional platform functionality. These capitalized software development costs are amortized over the estimated useful life of the underlying technology and are included in platform operations expenses.

The increase in general and administrative expense in 2015 was primarily due to an increase in personnel costs, excluding stock-based compensation, of $3.6 million, an increase in professional services fees of $1.9 million and an increase in bad debt expense of $0.4 million, partially offset by a reduction in stock compensation expense of $3.5 million primarily associated with the repurchase of common stock from our founders, concurrent with our Series B preferred stock financing in February 2014. The increase in personnel costs was primarily due to increased headcount. The increase in headcount and third-party professional services fees was primarily related to finance and legal services to support our growth and for preparation for an initial public offering. The increase in bad debt expense reflected the growth of our client base and increase in our accounts receivable.

The increase in other expense, net in 2015 primarily related to the increase of $5.4 million in the fair value of our convertible preferred stock warrant liabilities due to the increase in the valuation of our preferred stock from December 31, 2014 to December 31, 2015. In addition, foreign currency exchange losses increased by $0.7 million for the year ended December 31, 2015 compared to the year ended December 31, 2014 related to increased volume of foreign currency denominated transactions and fluctuations in exchange rates, primarily the Canadian Dollar relative to the U.S. Dollar from January 1, 2015 to December 31, 2015.

We had an effective income tax benefit of 100.5% in 2014 compared to an effective income tax rate of 46.6% in 2015. The effective tax rate in 2014 of 100.5% versus the federal statutory income tax rate of 34% was primarily due to non-deductible stock based compensation, offset by the release of our valuation allowance in U.S. jurisdictions. The difference between the effective tax rate in 2015 of 46.6% and the federal statutory income tax rate of 35% was mainly due to state taxes, net of federal benefit, and a change in the fair value of our warrant liabilities.

The following tables set forth our quarterly unaudited consolidated statements of operations data in dollars and as a percentage of revenue for each of the ten quarters in the period ended June 30, 2016. We have prepared the quarterly unaudited consolidated statements of operations data on a basis consistent with the audited consolidated financial statements included elsewhere in this prospectus. In the opinion of management, the financial information in these tables reflects all adjustments, consisting only of normal recurring adjustments, which management considers necessary for a fair statement of this data. This information should be read together with the audited consolidated financial statements and related notes included elsewhere in this prospectus. The results of historical periods are not necessarily indicative of the results for any future period.

	Three Months Ended

	Mar 31, 2014			Jun 30, 2014			Sept 30, 2014			Dec 31, 2014			Mar 31, 2015		Jun 30, 2015		Sept 30, 2015		Dec 31, 2015		Mar 31, 2016			Jun 30, 2016
	(in thousands)
Revenue	$	6,508		$	8,381		$	11,187		$	18,472		$	17,958	$	24,452	$	28,768	$	42,658	$	30,378		$	47,182
Operating expenses:
Platform operations		2,308			3,096			3,364			3,791			4,521		5,121		5,968		7,357		7,513			8,682
Sales and marketing		2,672			3,631			3,640			4,647			4,967		6,725		6,838		8,264		8,431			11,251
Technology and development		2,130			1,434			1,578			2,108			2,279		2,817		3,411		4,312		4,639			5,763
General and administrative		4,752			1,213			1,522			1,898			2,529		2,648		3,359		4,740		6,399			6,452

Total operating expenses		11,862			9,374			10,104			12,444			14,296		17,311		19,576		24,673		26,982			32,148

Income (loss) from operations		(5,354	)		(993	)		1,083			6,028			3,662		7,141		9,192		17,985		3,396			15,034
Total other expense, net		238			402			365			702			730		706		1,376		5,313		5,264			1,260

Income (loss) before income taxes		(5,592	)		(1,395	)		718			5,326			2,932		6,435		7,816		12,672		(1,868	)		13,774
Provision for (benefit from) income taxes		3,325			829			(428	)		(4,674	)		1,145		2,548		3,211		7,022		(828	)		6,176

Net income (loss)	$	(8,917	)	$	(2,224	)	$	1,146		$	10,000		$	1,787	$	3,887	$	4,605	$	5,650	$	(1,040	)	$	7,598

The following table sets forth our unaudited consolidated results of operations for the specified periods as a percentage of our revenue for those periods.

	Three Months Ended

	Mar 31, 2014			Jun 30, 2014			Sept 30, 2014			Dec 31, 2014			Mar 31, 2015			Jun 30, 2015			Sept 30, 2015			Dec 31, 2015			Mar 31, 2016			Jun 30, 2016
	*(as a percentage of revenue)**
Revenue		100	%		100	%		100	%		100	%		100	%		100	%		100	%		100	%		100	%		100	%
Operating expenses:
Platform operations		35			37			30			21			25			21			21			17			25			18
Sales and marketing		41			43			33			25			28			28			24			19			28			24
Technology and development		33			17			14			11			13			12			12			10			15			12
General and administrative		73			14			14			10			14			11			12			11			21			14

Total operating expenses		182			112			90			67			80			71			68			58			89			68

Income (loss) from operations		(82	)		(12	)		10			33			20			29			32			42			11			32
Total other expense, net		4			5			3			4			4			3			5			12			17			3

Income (loss) before income taxes		(86	)		(17	)		6			29			16			26			27			30			(6	)		29
Provision for (benefit from) income taxes		51			10			(4	)		(25	)		6			10			11			16			(3	)		13

Net income (loss)		(137	)%		(27	)%		10	%		54	%		10	%		16	%		16	%		13	%		(3	)%		16	%


Large accelerated filer o		Accelerated filer o		Non-accelerated filer ý (Do not check if a smaller reporting company)		Smaller reporting company o

Title of Each Class of Securities to be Registered	Amount to be Registered⁽¹⁾	Proposed Maximum Offering Price Per Share	Proposed Maximum Aggregate Offering Price	Amount of Registration Fee⁽²⁾




Class A Common Stock, par value $0.000001 per share	5,366,667	$18.00	$96,600,006	$9,727.62

	Per Share	Total

Public Offering Price	$	$
Underwriting Discount	$	$
Proceeds to The Trade Desk, Inc. (before expenses)	$	$


Citigroup	Jefferies	RBC Capital Markets
Needham & Company		Raymond James


Assumed initial public offering price per share				$	17.00
Historical net tangible book value per share as of June 30, 2016	$	4.67
Pro forma decrease in net tangible book value per share		(2.90	)

Pro forma net tangible book value per share as of June 30, 2016		1.77
Increase in pro forma net tangible book value per share attributable to new investors		1.65

Pro forma as adjusted net tangible book value per share after this offering					3.42

Dilution per share to investors in this offering				$	13.58


Delaware (State or other jurisdiction of incorporation or organization)		7370 (Primary Standard Industrial Classification Code Number)		27-1887399 (I.R.S. Employer Identification Number)


Copies to:
W. Alex Voxman Steven B. Stokdyk Latham & Watkins LLP 355 South Grand Avenue Los Angeles, California 90071 (213) 485-1234		Michael Nordtvedt Damien Weiss Wilson Sonsini Goodrich & Rosati Professional Corporation 650 Page Mill Road Palo Alto, California 94304 (650) 493-9300

		Page

Summary			1
Risk Factors			13
Special Note Regarding Forward-Looking Statements			42
Market, Industry and Other Data			44
Use of Proceeds			45
Dividend Policy			46
Capitalization			47
Dilution			50
Selected Consolidated Financial Data			53
Management's Discussion and Analysis of Financial Condition and Results of Operations			56
Business			82
Management			97
Executive Compensation			106
Certain Relationships and Related Party Transactions			122
Principal and Selling Stockholders			125
Description of Capital Stock			128
Shares Eligible for Future Sale			134
Material U.S. Federal Income Tax Consequences to Non-U.S. Holders			137
Underwriting			141
Legal Matters			148
Changes in Accountants			148
Experts			148
Where You Can Find Additional Information			149
Index to Consolidated Financial Statements			F-1
Index to Unaudited Condensed Consolidated Financial Statements			F-37

						Total Consideration

	Shares Purchased
	Shares Purchased										Average Price Per Share
	Number		Percent			Amount		Percent			Average Price Per Share
Existing stockholders		33,562		88	%	$	86,676		52	%	$	2.58
New investors		4,667		12			79,333		48			17.00

Total		38,229		100	%	$	166,009		100	%	$	4.34

	Six Months Ended June 30,

	2015		2016		$ Change		% Change
	(in thousands, except percentages)
Revenue	$	42,410	$	77,560	$	35,150		83	%