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mgni-20251231

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

__________________

FORM 10-K

__________________

(Mark One)

☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from _____________ to _____________

Commission File Number: 001-36384

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MAGNITE, INC.

(Exact name of registrant as specified in its charter)

__________________

(Address of principal executive offices, including zip code)

Registrant's telephone number, including area code:

______________

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Common stock, par value $0.00001 per share MGNI Nasdaq Global Select Market

Securities registered pursuant to Section 12(g) of the Act:

None

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Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ☐ Yes ☒No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. ☐ Yes ☒No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. ☒Yes☐ No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). ☒Yes☐ No

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

Large accelerated filer ☒ Accelerated filer ☐

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). ☐ Yes ☒ No

As of June 30, 2025, the aggregate market value of shares held by non-affiliates of the registrant (based on the closing sales price of such shares on the Nasdaq Global Select Market on June 30, 2025) was approximately $2,045,628,555.

Indicate the number of shares outstanding of each of the registrant's classes of common stock, as of the latest practicable date.

Class Outstanding as of February 19, 2026

DOCUMENTS INCORPORATED BY REFERENCE: To the extent herein specifically referenced in Part III, portions of the Registrant's definitive Proxy Statement for the 2026 Annual General Meeting of Shareholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A. See Part III.

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MAGNITE, INC.

FORM 10-K

FOR THE FISCAL YEAR ENDED DECEMBER 31, 2025

TABLE OF CONTENTS

PageNo.

Special Note About Forward-Looking Statements; Summary of Risk Factors 3

Part I

Item 1. Business 6

Item 1A. Risk Factors 15

Item 1B. Unresolved Staff Comments 38

Item 1C. Cybersecurity 39

Item 2. Properties 41

Item 3. Legal Proceedings 41

Item 4. Mine Safety Disclosures 41

Part II

Item 6. Reserved 43

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 59

Item 8. Financial Statements and Supplementary Data 61

Item 9A. Controls and Procedures 103

Item 9B. Other Information 105

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 105

Part III

Item 10. Directors, Executive Officers and Corporate Governance 105

Item 11. Executive Compensation 105

Item 14. Principal Accountant Fees and Services 106

Part IV

Item 15. Exhibits, Financial Statement Schedules 107

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SPECIAL NOTE ABOUT FORWARD-LOOKING STATEMENTS; SUMMARY OF RISK FACTORS

This Annual Report on Form 10-K and related statements by the Company contain forward-looking statements, including statements based upon or relating to our expectations, assumptions, estimates, and projections. In some cases, you can identify forward-looking statements by terms such as "may," "might," "will," "objective," "intend," "should," "could," "can," "would," "expect," "believe," "design," "anticipate," "estimate," "predict," "potential," "plan" or the negative of these terms, and similar expressions. Forward-looking statements may include, but are not limited to, statements concerning the Company's guidance or expectations with respect to future financial performance; acquisitions by the Company, or the anticipated benefits thereof; macroeconomic conditions or concerns related thereto; the growth of ad-supported programmatic connected television ("CTV"); our ability to use and collect data to provide our offerings; the scope and duration of client relationships; the fees we may charge in the future; key strategic objectives; anticipated benefits of new offerings; business mix; sales growth; benefits from supply path optimization; our ability to adapt to advancements in artificial intelligence ("AI"); the development of identity solutions; client utilization of our offerings; the impact of requests for discounts, rebates, or other fee concessions; our competitive differentiation; our market share and leadership position in the industry; market conditions, trends, and opportunities; the effects of regulatory developments or antitrust rulings on competitive dynamics in our industry; our litigation against Google LLC, or the anticipated benefits thereof; certain statements regarding future operational performance measures; and other statements that are not historical facts. These statements are not guarantees of future performance; they reflect our current views with respect to future events and are based on assumptions and estimates and subject to known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from expectations or results projected or implied by forward-looking statements.

Risks that our business faces include, but are not limited to, the following:

•the impact of macroeconomic challenges on the overall demand for advertising and the advertising marketplace;

•we operate in an intensely competitive market that includes companies that have greater financial, technical and marketing resources than we do;

•the freedom of buyers and sellers to direct their spending and inventory to competing sources of inventory and demand, and to establish direct relationships and integrations without the use of our platform;

•CTV spend on our platform may grow more slowly than we expect, growth may occur disproportionately through platforms or applications that we cannot access, or we may not be able to maintain or increase access to advertising inventory;

•CTV sellers may not adopt or may be slow to adopt programmatic solutions that transact in biddable auction environments;

•we may not be able to maintain or increase access to the CTV advertising inventory monetized through our platform on terms acceptable to us;

•advancements in AI have and are likely to continue to lead to a decrease in search referral traffic for open web display publishers, which in turn may result in decrease in the amount of web display inventory monetized through our platforms;

•AI may significantly affect the competitive dynamics of our industry, we may fail to effectively build AI features into our platform, and we may be ineffective in using AI to realize internal efficiencies;

•the regulatory landscape governing AI is still developing, and our use of third party AI tools may result in increased legal and regulatory scrutiny, litigation, and reputational harm;

•we may be unsuccessful in our supply path optimization efforts with buyers;

•our ability to introduce new offerings and bring them to market in a timely manner, and potential responses or reactions of clients, vendors, and competitors to the announcement of new products and offerings;

•our ability to increase the scale and efficiency of our technology infrastructure to support our growth, including in response to header bidding and other advancements in technology;

•our access to mobile inventory may be limited by third-party technology or lack of direct relationships with mobile sellers;

•the impact of requests for discounts, fee concessions, rebates, refunds or favorable payment terms;

•we may experience lower take rates, which may not be offset by increases in ad spend;

•we may be unable to achieve sustained profitability in the future;

•our business may be subject to sales and use tax, value-added/goods and services, advertising, digital services, withholding and other taxes;

•operating results may fluctuate, be difficult to predict, and fall below analysts' and investors' expectations as a result of seasonal trends, consolidation in our industry, our ability to differentiate our offerings and compete effectively to combat disintermediation, and other factors;

•our ability to realize the anticipated benefits of any acquisitions;

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•our ability to provide value to both buyers and sellers of advertising without being perceived as favoring one over the other or being perceived as competing with them through our service offerings;

•our reliance on large sources of advertising demand, including demand side platforms ("DSPs") that may have or develop high-risk credit profiles or fail to pay invoices when due;

•failure by us or our clients to meet advertising and inventory content standards;

•our sales efforts may require significant time and expense and may not yield the results we seek;

•we may be exposed to claims from clients for breach of contract;

•our reliance on third-party open source software components;

•potential limitations on our ability to collect or use data as a result of consumer tools, regulatory restrictions and technological limitations;

•the deprecation of third-party cookies and other identifiers, and the development of new targeting and identity solutions, may disrupt the programmatic ecosystem, cause reduced CPMs and fill rates, result in a shift of ad spend towards "walled gardens," require additional investment and resources, and cause the overall performance of our platform to decline;

•the industry may not adopt or may be slow to adopt the use of first-party publisher segments as an alternative to third-party cookies;

•the impact of antitrust regulations or enforcement actions targeting the digital advertising ecosystem;

•our ability to comply with, and the effect on our business of, evolving legal standards and regulations, particularly concerning data protection and privacy and evolving corporate governance and public disclosure regulations and expectations;

•ramifications of our litigation with Google LLC;

•errors or failures in the operation of our solution, interruptions in our access to network infrastructure or data, and breaches of our computer systems including as a result of cyber security incidents;

•our ability to ensure a high level of brand safety for our clients and to detect "bot" traffic and other fraudulent or malicious activity;

•our ability to attract and retain qualified employees and key personnel;

•costs associated with enforcing our intellectual property rights;

•our ability to comply with the terms of our financing arrangements;

•restrictions in our Credit Agreement may limit our ability to make strategic investments, respond to changing market conditions, or otherwise operate our business;

•increases in our debt leverage may put us at greater risk of defaulting on our debt obligations, subject us to additional operating restrictions and make it more difficult to obtain future financing on favorable terms;

•conversion of our Convertible Senior Notes would dilute the ownership interest of existing stockholders;

•the Capped Call Transactions subject us to counterparty risk and may affect the value of the Convertible Senior Notes and our common stock;

•the conditional conversion feature of the Convertible Senior Notes, if triggered, may adversely affect our financial condition and operating result;

•failure to successfully execute our international growth plans;

•failure to maintain an effective system of internal control over financial reporting, which could adversely affect investor confidence;

•the use of our net operating losses and tax credit carryforwards may be subject to certain limitations;

•our ability to raise additional capital if needed;

•volatility in the price of our common stock;

•the impact of our repurchase program on our stock price and cash reserves; and

•provisions of our charter documents and Delaware law may inhibit a potential acquisition of the company and limit the ability of stockholders to cause changes in company management.

We discuss many of these risks and additional factors that could cause actual results to differ materially from those anticipated by our forward-looking statements under the headings "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations," and elsewhere in this report and in other filings we have made and will make from time to time with the Securities and Exchange Commission, or SEC. These forward-looking statements represent our estimates and assumptions only as of the date of the report in which they are included. Unless required by federal securities laws, we assume no obligation to update any of these forward-looking statements, or to update the reasons actual results could differ materially from those anticipated, to reflect circumstances or events that occur after the statements are made. Without limiting the foregoing, any guidance we may provide will generally be given only in connection with quarterly and annual

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earnings announcements, without interim updates, and we may appear at industry conferences or make other public statements without disclosing material nonpublic information in our possession. Given these uncertainties, investors should not place undue reliance on these forward-looking statements.

Investors should read this Annual Report on Form 10-K and the documents that we reference in this report and have filed or will file with the SEC completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of our forward-looking statements by these cautionary statements.

NOTE REGARDING THIRD-PARTY INFORMATION

This Annual Report on Form 10-K includes data that we obtained from industry publications and third-party research, surveys and studies. While we believe the industry publications and third-party research, surveys and studies are reliable, we have not independently verified such data. Such third-party data and our internal estimates and research are necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in "Item 1A. Risk Factors" in this Annual Report on Form 10-K. These and other factors could cause results to differ materially from those included in this report.

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PART I

Item 1. Business

Overview

Magnite, Inc., ("we," or "us"), provides technology solutions to automate the purchase and sale of digital advertising inventory.

We believe that we are the world's largest independent omni-channel sell-side advertising platform ("SSP"), offering a single partner for transacting globally across all channels, formats and auction types, and the largest independent programmatic CTV marketplace, making it easier for buyers to reach CTV audiences at scale from industry-leading streaming content providers, broadcasters, platforms and device manufacturers.

Our platform features applications and services for sellers of digital advertising inventory, or publishers, that own and operate CTV channels, applications, websites and other digital media properties, to manage and monetize their inventory; applications and services for buyers, including advertisers, agencies, agency trading desks, and demand side platforms ("DSPs"), to buy digital advertising inventory; and a transparent, independent marketplace that brings buyers and sellers together and facilitates intelligent decision making and automated transaction execution at scale. Our clients include many of the world’s leading buyers and sellers of digital advertising inventory. Our platform processes trillions of ad requests per month, allowing buyers access to a global, scaled, independent alternative to "walled gardens," who both own and sell inventory and maintain control on the demand side.

Our SpringServe CTV platform offers CTV sellers a holistic solution to manage and monetize their entire portfolio of CTV ad inventory, across both programmatic and direct-sold video inventory. We provide sellers with a full suite of tools to protect the consumer viewing experience and brand safety expectations, while increasing revenue opportunities, including tools for mediation and yield optimization, forecasting tools, customized ad experiences and ad formats, and advanced podding logic. These tools are particularly important to CTV sellers who need to provide a TV-like viewing and advertising experience for consumers. For instance, our ad-pod feature provides publishers with a tool analogous to commercial breaks in traditional linear television so that they can request and manage several ads at once from different demand sources. Other tools we offer include audio normalization tools to control for the volume of an ad relative to content, frequency capping to avoid exposing viewers to repetitive ad placements, and creative review so that a publisher can review and approve the ad units being served to its properties.

Buyers leverage our platform to reach their target audiences across thousands of sellers in a premium brand-safe environment. We offer a suite of tools designed to help buyers discover and curate inventory, simplify workflow and execute on their campaign objectives in a cost effective manner. For instance, our ClearLine product provides buyers with direct access to premium CTV inventory and integrated curation capabilities, enabling buyers to build custom deal packages that can be enriched with high-fidelity first-party or third-party data. We believe that our scale, platform features, and omni-channel offering makes us an essential partner for buyers.

We operate our business on a worldwide basis, with an established operating presence in North America, Australia and Europe, and a developing presence in Asia and South America. Our non-U.S. subsidiaries and operations perform primarily sales, marketing, and service functions.

Industry Trends

Continued Shift Toward Digital Advertising

Consumers are rapidly shifting their viewing habits towards digital mediums and expect to be able to consume content seamlessly across multiple devices, including computers, tablets, smartphones, and CTVs whenever and wherever they want. As digital content consumption continues to proliferate, we believe the percentage of advertising dollars spent through digital channels will continue to grow.

Automation of Buying and Selling

Due to the size and complexity of the digital advertising ecosystem and purchasing process, manual processes cannot effectively manage digital advertising inventory at scale. In addition, both buyers and sellers are demanding more transparency, better controls and more relevant insights from their advertising inventory purchases and sales. This has created a need for software solutions, known as programmatic advertising, that automate the process for planning, buying, selling and measuring digital advertising across screens. Programmatic transactions include biddable auctions, where multiple buyers bid against each other in a real-time auction for the right to purchase a publisher's inventory, as well as reserve auctions, where publishers

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establish direct deals or private marketplaces with select buyers. These reserve auctions may also be “guaranteed,” where a buyer has negotiated a pre-established price and volume with a seller, otherwise referred to as "programmatic guaranteed."

Convergence of TV and Digital

CTV viewership is growing rapidly and the pace of adoption is accelerating the transition of linear television to CTV programming. Initially, many streaming services were subscription based, but as the market has matured, the largest streaming publishers have adopted ad-supported models or hybrid models that rely on a combination of subscription fees and advertising. With the proliferation of CTV advertising inventory, we believe that brand advertisers looking to engage with streaming viewers will continue to shift their budgets from linear to CTV. Moreover, we believe that as the amount of CTV inventory continues to scale, it will become increasingly more accessible to small and medium sized businesses, many of whom have no experience advertising on linear TV. This transition is likely to be accelerated by advancements in AI, which have simplified the process and reduced the cost of producing TV-ready ad creatives. As the advertiser base for CTV expands and diversifies, we believe CTV sellers will make a greater percentage of inventory available through biddable auction environments with multiple buyers rather than programmatic guaranteed. We believe that this shift, if it were to occur, would likely be beneficial to our CTV growth as biddable transactions tend to require a higher level of service and therefore carry a higher take-rate compared to reserve auctions.

We have made and plan to continue to make significant investments in technology, sales and support related to our CTV growth initiatives, and believe CTV will be a significant driver of our revenue growth for the foreseeable future. In April 2025, we announced the introduction of our next generation SpringServe CTV platform. The new SpringServe platform combines the features and functionalities of our streaming SSP and ad server to provide a more efficient connection for buyers to premium CTV supply, while offering powerful mediation tools and streamlined workflow for sellers through a single user interface.

Identity Solutions

One of the advantages of programmatic advertising is that it enables more precise audience targeting, which is generally more effective and valuable for buyers than other types of advertising, resulting in better performance for buyers and more revenue for sellers. Historically, in desktop and mobile, one of the primary methods for delivering targeted advertisements was through the use of third-party cookies. However, in recent years the use of third-party cookies and other tracking technologies that collect user information have come under greater scrutiny due to privacy concerns, and a number of participants in the advertising technology ecosystem have taken steps to eliminate or restrict the use of these technologies.

In the long term, we believe that a decreased reliance on third-party cookies and other non-transparent tracking methods would be a positive for the industry, and offer the potential to shift the programmatic ecosystem from an identity model powered by buyers that are able to aggregate and target audiences through cookies to one enabled by sellers that have direct relationships with consumers and are therefore better positioned to obtain user data and consent for implementing first party identifiers. In CTV, where third-party cookies do not exist, this identity model already largely exists with publishers more tightly controlling access to identifiers and user data, while offering proprietary first party data segments for reaching desired audiences.

We believe that our scale and expertise in CTV position us well to take a leadership position in advancing this shift to a first-party identity model and creating additional value opportunities for our clients. Accordingly, we have invested and intend to further invest in the development and enhancement of industry leading identity and audience solutions, such as our Magnite Curator Marketplace, a self-service solution integrated within ClearLine. The Magnite Curator Marketplace allows the creation of custom deal packages for buyers that include curated pools of premium inventory that can be enriched with the curator's first-party or third-party data.

Supply Path Optimization

Supply Path Optimization ("SPO") refers to efforts by buyers to consolidate the number of vendors with which they work to find the most effective and cost-efficient paths to procure media.

Our SPO efforts with buyers are important because they allow us to build deeper relationships with buyers and potentially attract unique advertising demand, which, in turn, increase revenue opportunities for our seller clients. We typically enter into SPO agreements directly with agencies or agency holding companies, as well as brands and DSPs, which may

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provide for custom integrations, data flows or volume-based discounts. Under these SPO agreements, we may be designated as a preferred partner or otherwise enter into terms intended to increase the overall spend on our platform.

We believe we are well positioned to benefit from SPO in the long run as a result of our transparency, our broad and unique inventory supply across all channels and formats, buyer tools, such as our ClearLine product offering and buyer marketplaces, traffic filtering technology that reduces the cost of working with us, and brand safety measures.

Header Bidding and Data Processing

Header bidding is a programmatic technique by which sellers offer inventory to multiple ad exchanges and supply side platforms, such as our platform, simultaneously. Header bidding has been adopted in the desktop and mobile channels, largely as a counterweight to Google's dominance in the display ad server market. The adoption of header bidding in desktop and mobile display has created a number of challenges and technical complexities for both sellers and buyers, which require sophisticated tools to manage.

In addition, header bidding has led to a significant increase in the number of ad impressions to be processed and analyzed through our platform as well as by DSPs, which can lead to increased costs if not properly addressed. We continuously work to increase the operational efficiency of our platform, so as to enable buyers and sellers to achieve their campaign and monetization objectives in a cost-effective manner.

In CTV, solutions similar to header bidding that are geared towards increasing demand competition have largely been built directly within the ad server. For instance, our SpringServe CTV platform enables sellers to offer their inventory to multiple programmatic demand sources to compete in a unified auction.

Magnite: Competitive Strengths of Our Platform. Key competitive strengths of our platform include:

Leadership in CTV

Our Magnite SpringServe platform, which combines programmatic, ad serving, and mediation functionality, has been built to meet the unique requirements of CTV sellers and we have invested significant time and resources in cultivating relationships with these sellers through our specialized team of CTV experts.

Many CTV sellers have their roots in linear television and it is important that established business practices in television advertising can be translated to programmatic advertising. The tools we provide include ad podding for commercial breaks, dynamic ad insertion to serve live streaming events, audio normalization tools to control the volume of an ad relative to content, frequency capping to avoid exposing viewers to repetitive ad placements, and creative review so that a publisher can review and approve the ad units being served to its properties. In addition, SpringServe Home Screen Ads is an innovative feature that allows publishers to showcase custom creative and highlight content recommendations within streaming programming guides in any size and a wide variety of formats.

Scaled Omni-Channel Platform

We offer a scaled omni-channel platform that brings value to both buyers and sellers of ad inventory. For buyers, we offer a single omni-channel partner to reach target audiences globally across all channels, including CTV, mobile, and desktop, and formats, including video, display, and audio. For sellers, we partner as a one stop shop where they can sell digital advertising across all of their properties, regardless of device or format, and gain instant access to the world’s largest automated digital advertising buyers with the flexibility to sell their advertising inventory in an automated fashion on an impression-by-impression basis. We believe large numbers of diverse sellers on our platform attract more buyers and vice versa, resulting in a self-reinforcing network effect that adds value for all our clients and creates a stickier platform solution.

Reserve Auctions and Deal Management

A significant portion of premium inventory, in particular with respect to CTV, is purchased and sold through reserve auctions where the seller establishes a direct deal with a buyer or group of buyers. These transaction types allow the seller to maintain tighter control over their advertising allocation and are often used by sellers that maintain a direct sales force but still want to experience the benefits of automation to improve pricing, matching, and dynamic ad placement and to automate manual operations such as ad trafficking, quality assurance, and billing and collections. Our deal management and curation tools support sales functions rather than replacing them, which eliminates friction in the sales process.

Big Data Analytics and Machine-Learning Algorithms; Bid Filtering

A core aspect of our value proposition is our big data and machine-learning platform, a subcategory of artificial intelligence, which is able to discover unique insights from our massive data repositories. Our systems collect and analyze a myriad of information such as historical clearing prices, bid responses, ad formats, user location, how many ads the user has seen, browser or device information, and sellers’ first party data about users. Our access to data puts us in a unique position to develop differentiated insights to help both buyers and sellers. Our solution utilizes artificial intelligence in order to constantly self-improve as we process more volume and accumulate more data, which in turn helps make our machine-learning algorithms

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more intelligent and contributes to higher-quality matching between buyers and sellers. This data also fuels our bid filtering technology, allowing us to more aggressively block traffic that is not likely to monetize. We believe that our traffic optimization coupled with bid filtering improves return on investment for buyers and increases revenue for sellers, which in turn attracts more buyers and sellers to our platform creating a dual network effect that makes our platform stickier. These capabilities also help us manage the costs associated with the high volumes of ad requests we receive.

Identity Solutions

We offer identity solutions that help buyers and sellers create better matches and increase advertising return on investment ("ROI") and the value of the underlying impression.Our tools enable sellers to create audience segments based on first-party data, which makes their advertising inventory more valuable to buyers looking to achieve specific campaign goals.In addition, our technology is integrated with a number of third-party data, attribution and identity vendors, allowingbuyers and sellers to leverage these solutions directly through our platform without the need for multiple vendor contracts. As described above, in 2025, we launched the Magnite Curator Marketplace, which allows for the creation of custom deal packages that can be enriched with first-party or third-party data.

Header Bidding and Demand Manager Solutions

We are integrated with all of the major header-bidding standards for display inventory, including Prebid.org, which we co-founded, as well as the solutions offered by Google and Amazon. We believe the various header bidding alternatives we offer, our buyer reach and scale, our buying efficiency, and our machine-learning capabilities put us in a strong position to compete for seller impressions monetized through header-bidding solutions, and we expect these header bidding solutions to deliver a meaningful volume of impressions. We also provide a software solution called Demand Manager that helps desktop and mobile sellers manage all of their header-bidding advertising inventory. We believe that adoption and proliferation of these tools will further strengthen our relationship with sellers and contribute to our future revenue growth.

Transparency and Controls

We generate revenue each time an impression is monetized on our platform based on a simple and transparent fee structure established with our publisherpartners.Our clients direct the sale and management of ad inventory through our platform, including the ability to define supply hierarchies and demand tiers, set minimum price floors, and establish advertiser and category level blocked and allowed lists.We provide sellers with detailed analytics, which allows them to effectively monitor buying patterns and make real-time changes to take advantage of market dynamics and maximize their yield.

Self-Service Model

We offer a self-service model that allows sellers to access our platform without extensive involvement by our personnel.This model allows us to scale efficiently and grow our business at a faster pace than the growth of our sales and support organization. As a result, we are able to achieve a high degree of operating leverage, which positions our business for growing profitability.

Buyer Tools

We provide a suite of buyer tools designed to help buyers discover and curate inventory, append data and improve ROI in order to meet their campaign strategies. For instance, our buyer marketplace tools enable agency holding companies and other large buyers to create their own private label marketplaces for their advertiser clients, while establishing direct connections with sellers. Our custom auction packages and audience tools give buyers a versatile and cost-effective way to target inventory, using categories such as audience, context, and viewability, while our deal discovery platform allows buyers to connect directly with sellers to arrange direct reserve auctions. Finally, our ClearLine product is a self-service solution that provides buyers with direct access to premium CTV and integrated curation capabilities, enabling buyers to build custom deal packages that can be enriched with high-fidelity first-party or third-party data. This solution helps buyers maximize the spend going towards working media, makes it easier for sellers and agencies to securely share data, improves workflow for campaigns traditionally transacted manually, and helps publishers generate more revenue and develop new sources of unique demand.

In September 2025, the Company completed the acquisition of Streamrai, Inc. ("Streamr.ai"), a platform that specializes in artificial intelligence tools that make CTV advertising accessible to small and medium-sized businesses. The Streamr.ai technology leverages generative AI to automate the creation of broadcast-quality video ads and streamline campaign setup, allowing advertisers to launch CTV campaigns in significantly less time than traditional methods. These self-service tools help enable a wider range of local and regional businesses to advertise on CTV.

SPO and Demand Generation

We expend a significant amount of resources cultivating relationships directly with brands and advertising agencies in order to increase revenue opportunities for sellers on our platform. One of the ways we attract demand to our platform is through entering into SPO agreements directly with buyers, such as major agency holding companies, which provide for custom integrations, data flows or volume-based discounts. Under these SPO agreements, we may be designated as a preferred partner or otherwise enter into terms intended to increase the overall spend on our platform. In addition, we also offer brands and

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agencies the ability to access our platform directly, including on a managed service basis through the use of insertion orders and programmatically through our ClearLine product offering. As such, we believe our SPO and other buyer-facing initiatives allow us to provide sellers with access to a pool of differentiated demand.

Independence

We are fully aligned with the interests of our publisher clients. Unlike some large industry participants, we do not have our own media properties that compete for advertising spending with our sellers.In addition, because we do not offer a dedicated demand side platform, we are able to avoid inherent conflicts of interest that exist when serving both the buy- and sell-side.

Magnite: Growth Strategies. The key elements to our long-term growth strategy include:

Focus on CTV

As streaming video continues to become mainstream and ad-supported models become more prevalent, we believe advertisers will continue to shift budgets to CTV. We expect CTV to be the biggest driver of our growth and plan to invest significant resources in technology, sales and support related to our CTV growth initiatives. In particular, we intend to invest in additional features to support publishers with the monetization of live events such as sports. Live events are particularly challenging for publishers due to constant shifts in audience sizes that can be difficult to plan for and often result in monetized ad opportunities. As live events continue to become more prevalent among streaming services, we believe there is an opportunity for innovative technology to address these problems. For instance, our Live Stream Acceleration product helps publishers deal with traffic spikes by managing the pacing of ad requests and queuing pre-approved ad pods in advance of an anticipated ad break.

Supply Path Optimization

As described above, SPO refers to efforts by buyers to consolidate the number of vendors with which they work to find the most effective and cost-efficient paths to procure media. We believe we are well positioned to benefit from SPO due to the factors described above and that it presents an opportunity for us to capture market share and increase the volume of advertising spend on our platform.

Identity Solutions

As the largest independent supply side platform, we believe we are well positioned to take a leadership role in advancing the shift away from third-party cookies and similar third-party identifiers to a model that is powered by sellers that have access to valuable first-party data, creating additional opportunities for our clients. Accordingly, we have invested and intend to further invest in the development and enhancement of industry leading identity and audience solutions.

Increase Efficiencies on our Exchange

We aim to increase the operational efficiency of our platform, so as to enable buyers and sellers to achieve their campaign and monetization objectives in a cost-effective manner. Our solution is constantly self-improving as we process more volume and accumulate more data and we are continuing to invest in traffic optimization and bid filtering technology to allow us to monetize a higher proportion of the ad requests on our platform, which reduces costs for us as well as the process costs for buyers. We believe these cost savings make our platform more attractive to buyers, which in turn improves revenue opportunities for sellers.

Increasing Seller Inventory

In order to increase transaction volume we are continuously looking to add new high quality sellers to our platform and to expand our existing relationships with sellers to increase our share of their inventory, in particular in CTV where inventory is controlled by fewer sellers. Our plan for increasing our inventory volumes includes establishing and deepening our direct relationships with sellers, including through adoption of our SpringServe ad server, custom integrations, expanding our seller tools, capitalizing on our omni-channel capabilities, and leveraging our header bidding integrations, including through Demand Manager.

Expand our International Footprint

With established operating presence in North America, Australia and Europe, and a developing presence in Asia and South America, we serve buyers and sellers on a global basis. We plan to continue to expand our international presence and make additional investments in sales, marketing and infrastructure to support our long-term growth and to position ourselves for expected increases in programmatic advertising globally. We expect programmatic advertising to grow at different rates in

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different geographic markets, and are constantly evaluating new markets with a strategy to use our existing infrastructure and adjacent sales offices or by expanding our infrastructure footprint and placing personnel directly in those markets.

Continue to Innovate and Enhance our Platform

We are working on a number of platform innovations and enhancements designed to improve the value of our services to our clients, including new features and ad formats on our streaming ad server, tools that facilitate the creation of audience segments, as well as developing a product suite specifically to address the challenges of live streaming.

How We Generate Revenue

Digital advertising inventory is created when consumers access sellers' content. Sellers provide digital advertising inventory to our platform in the form of advertising requests, or ad requests. When we receive ad requests from sellers, we send bid requests to buyers, which enable buyers to bid on sellers’ digital advertising inventory. Winning bids can create advertising, or paid impressions, for the seller to present to the consumer. The price that buyers pay for each thousand paid impressions purchased is measured in units referred to as CPM, or cost per thousand, and the total volume of spending between buyers and sellers on our platform is referred to as advertising spend.

We generate revenue from the use of our platform for the purchase and sale of digital advertising inventory. Generally, our revenue is based on a percentage of the ad spend that runs through our platform, although for certain clients, services, or transaction types, including ad serving, we may receive a fixed CPM for each impression sold, and for advertising campaigns that are transacted through insertion orders, we earn revenue based on the full amount of ad spend that runs through our platform. In addition, we may receive certain fixed monthly fees for the use of our platform or products.

Channels

Sellers use our technology to monetize their content across all digital channels, including CTV, mobile, and desktop. We refer to our mobile and desktop channels as DV+. Consistent with the IAB’s definition of CTV, CTV represents advertising transactions on our platform that are delivered to the end consumer via a television set that is connected to the Internet. Our CTV transactions do not include advertisements viewed on a mobile or desktop device. Mobile and desktop represent advertising transactions on our platform that are delivered to the end consumer via their respective devices’ operating system, that is, a mobile operating system or a traditional desktop operating system, respectively. Mobile devices generally refer to a handset, tablet, or other communication device that runs on a mobile operating system used to access the Internet wirelessly, usually through a mobile carrier or Wi-Fi network. Desktop transactions are those transactions delivered to the end user whose device runs on a traditional PC, laptops, as well as those delivered on mobile devices or tablets that are not running on mobile based operating systems.

Our Technology

To support a majority of our non-CTV transactions, we have developed a globally distributed infrastructure hosted at on-prem data centers in the U.S., Europe, and Asia that run our proprietary software. Currently, our CTV transactions run primarily on the cloud; however, in order to realize additional cost savings and operational efficiencies, we are continuing to invest in additional on-prem data centers to support a higher percentage of our CTV transactions. We believe these two approaches optimize the type of traffic we handle - hosted data centers for high-frequency, low-latency transactions and cloud-supported for lower frequency transactions subject to more volatile viewing patterns, for example CTV prime-time viewing spikes or live-events.

We believe our approach supports the volume, diversity, and complexity of buyers’ bidding patterns, which increases market liquidity. Our algorithms improve infrastructure load and execute transactions efficiently by only sending bid requests to those buyers of advertising inventory who can handle the volume and are likely to respond.

This infrastructure is supported by real-time data pipelines, a system that quickly moves volumes of data generated by our business into reporting and machine-learning systems for both internal and client use cases. It also is supported by a 24-hour Network Operations Center, which provides failure protection by monitoring and rerouting traffic in the event of equipment failure or network performance issues between buyers and our marketplace, and our core technology and

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development team, which is responsible for the design, development, operation, and maintenance of our platform, and employs an agile development process that emphasizes frequent, iterative, and incremental development cycles.

We believe that continued investment in technology and development is critical to our success and long-term growth.

Sales and Marketing

We market our solution to buyers and sellers through global sales teams that operate from various locations around the world. These teams leverage market knowledge and expertise to demonstrate the benefits of our solution to buyers and sellers. We deploy a professional services team with each seller integration to assist sellers in getting the most value from our platform. Our buyer team, which is separately managed, focuses on collaborating with and increasing spend from DSPs, agencies, and brands, and our client services teams work closely with clients to support and execute campaigns. Our marketing initiatives are focused on managing our brand, increasing market awareness, and driving advertising spend to our platform. We often present at industry conferences, create custom events, and invest in public relations. In addition, our marketing team advertises online, in print, and in other forms of media, creates case studies, sponsors research, writes whitepapers, publishes marketing collateral, generates blog posts, and undertakes client research studies.

Competition

Our industry is highly competitive. We compete for digital advertising spending against competitors that, in some cases, are also buyers and/or sellers on our platform. Many of our competitors, including Google, Facebook, Comcast, and Amazon, are significantly larger than us, with more established name recognition and access to greater financial resources. In addition, they benefit from direct relationships with users, own their own content, and have access to tremendous amounts of proprietary data.

Despite the dominance of large companies in digital advertising, there is still a large addressable market that is highly fragmented and includes many providers of transaction services with which we compete, including supply side platforms, video ad servers, and advertising exchanges. As we introduce new offerings, as our existing offerings evolve, or as other companies introduce new products and services, we may be subject to additional competition. There has been rapid evolution and consolidation in the advertising technology industry, and we expect these trends to continue, thereby increasing the capabilities and competitive posture of larger companies, particularly those that are already dominant in various ways, and enabling new or stronger competitors to emerge. There are many ways for buyers and sellers of digital advertising inventory to connect and transact, including directly and through many other exchanges, and buyers, including DSPs that transact on our platform, are increasingly establishing relationships directly with sellers of advertising inventory, which puts significant pressure on us. Our offering must remain competitive in scope, ease of use, scalability, speed, data access, price, inventory quality, brand security, customer service, identity protection and other technological features that help sellers monetize their inventory and buyers increase the return on their advertising investment. While our industry is evolving rapidly and becoming increasingly competitive, we believe that our solution enables us to compete favorably on these factors. In addition, we believe we enjoy a number of competitive strengths, as further detailed above.

Human Capital: Our Team and Culture

Our team draws from a broad spectrum of experience, including data science, infrastructure, software development, and from experienced leadership on the seller and buyer sides, including streaming, mobile and video. In addition to the United States, we have personnel and operations in Australia, Brazil, Canada, France, Germany, India, Italy, Japan, New Zealand, Singapore, Sweden, and the United Kingdom, in order to service buyers and sellers on a global scale.

Culture

We strive to build a culture that is high-performing and results-oriented while emphasizing growth, collaboration, diversity, and innovation. Our recruitment team seeks qualified individuals that are committed to seeing the big picture and being catalysts of change. We aim to recruit and develop talent from diverse backgrounds, to provide equal employment opportunity, and to champion a wide array of voices throughout the Company. We ask our employees to empower others and commit to making our company a great place to work, not just a "job," and are constantly striving to cultivate a culture of excellence in which employees feel safe as their authentic selves.

Talent Retention

We believe empowerment starts with investing in our employees, both inside and outside the office. We reward team and individual excellence and are committed to creating an exceptional workplace environment in which we seek feedback from our employees in regular engagement surveys. We believe in continual feedback on performance. Our employees set goals at a regular cadence throughout the year and managers provide achievement ratings at year-end. We continually invest in

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learning and leadership development programs and routinely analyze voluntary employee turnover to understand and address trends. We give equity to our employees to promote alignment and ownership.

Conduct

We are committed to promoting high standards of honest and ethical business conduct and compliance in alignment with our cultural values. We do not tolerate harassment or discrimination. Our employees are required to take annual harassment and discrimination training as well as acknowledge our Code of Business and Ethics Policy.

As of December 31, 2025, we had 971 full-time employees.

Our Intellectual Property

Our proprietary technologies are important and we rely upon trade secret, trademark, copyright, and patent laws in the United States and abroad to establish and protect our intellectual property and protect our proprietary technologies.

We have several issued patents and pending patent applications, some of which may ultimately be abandoned if we determine that the cost of prosecution or maintenance does not justify the utility of receiving the patent. None of these patents has been litigated and we do not believe that any individual patent or patent application is material to our business. Their importance to our business is uncertain and there are no guarantees that any of the patents will serve as protection for our technology or market in the United States or any other country in which an application has been filed.

We register certain domain names, trademarks and service marks in the United States and in certain locations outside the United States. We also rely upon common law protection for certain trademarks. We generally enter into confidentiality and invention assignment agreements with our employees and contractors, and confidentiality agreements with parties with whom we conduct business, in order to limit access to, and disclosure and use of, our proprietary information. We also use measures designed to control access to our technology and proprietary information. We view our trade secrets and know-how as a significant component of our intellectual property assets, which we believe differentiate us from our competitors.

Any impairment of our intellectual property rights, or any unauthorized disclosure or use of our intellectual property or technology, could harm our business, our ability to compete and our operating results.

Client Dynamics

Sellers

Sellers own or operate media properties, websites and applications through which advertisements can be delivered to consumers as they navigate across screens. Sellers use our platform to monetize and manage their advertising inventory.

While we work with many clients, a relatively small number of them provide a large share of the unique user audiences accessible by buyers. This is particularly true in CTV, where sellers tend to be larger compared to other online sellers. Given the limited number of CTV sellers, we are focused on building deeper, long-term strategic partnerships with these clients through a full-service business development strategy. We have invested significant resources in identifying and cultivating these relationships and our sales executives and account managers often serve a consultative role within a client’s sales organization to help establish best practices. This team is further supported by our product and engineering team with deep technical expertise, and for larger clients, we may build out custom features or functionality to help drive deeper adoption of our platform.

In the mobile channel, many of the application providers that make inventory available through our platform utilize system development kits ("SDKs") and other proprietary technology of third parties, such as aggregators, and it is those third parties, not the application providers themselves, that contract with us to help monetize the inventory. Termination or diminution of our relationships with these third parties could result in a material reduction of the amount of mobile inventory available through our platform. We encourage application developers to use our own SDK when appropriate, but it is difficult to displace existing SDKs.

Buyers

On the buy-side of our business, we maintain close relationships with brand advertisers and agencies, as well as the technological intermediaries through which they transact on our platform, principally DSPs.

DSPs are directly connected to our technology through server-to-server integrations and are responsible for bidding on and purchasing advertising inventory on our platform pursuant to master service agreements. We have relationships with all of

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the major DSPs, and because ad spend is highly concentrated among relatively few DSPs, each of our relationships with these DSPs is important to us and represents a source of demand that could be difficult for us to replace.

While the DSP is generally responsible for the direct purchasing of advertising inventory through our platform, the overall direction of an advertising campaign is typically determined by the advertiser or advertising agency that has engaged the DSP. As such, in order to increase the amount of spend transacted on our platform, and in furtherance of our SPO efforts, we expend significant resources establishing and expanding relationships directly with brand advertisers and agencies.

In addition to transacting through DSPs, we also offer brands and agencies the ability to access our platform directly, including on a managed service basis through the use of insertion orders and programmatically through our ClearLine product offering. For managed service campaigns, our team of specialists manages the delivery and execution of the campaign according to an agreed set of objectives with the advertiser or agency, at a negotiated fixed price. For ClearLine, advertisers and agencies use a self-service programmatic solution to directly access premium inventory on our platform.

Geographic Scope of Our Operations

The growth of programmatic advertising has expanded into geographic markets outside of the United States, and in some markets, the adoption rate of programmatic digital advertising is greater than in the United States. We face staffing challenges, including difficulty in recruiting, retaining, and managing a diverse and distributed workforce across time zones, cultures, and languages. We must also adapt our practices to satisfy local requirements and standards (including differing privacy requirements that are sometimes more stringent than in the U.S.), and manage the effects of global and regional pandemics, recessions and economic and political instability. Transactions denominated in various non-U.S. currencies expose us to potentially unfavorable changes in exchange rates and added transaction costs. Foreign operations expose us to potentially adverse tax consequences in the United States and abroad and costs and restrictions affecting the repatriation of funds to the United States. For detailed information regarding our revenue, property and equipment, net, and right-of-use assets by geographical region, see Note 4, Note 6, and Note 11 of the "Notes to Consolidated Financial Statements."

Regulation

Our business is highly susceptible to existing and emerging privacy regulations and oversight concerning the collection, use and sharing of data. Data protection authorities in the United States and around the world continue to focus on the advertising technology ecosystem. Because we, and our clients, rely upon large volumes of such data, it is essential that we monitor developments in this area domestically and globally, and engage in responsible data processing practices.

We do not collect information that can be used to directly identify a real person, such as name, address, or phone number, and we take steps to avoid collecting and storing such information. Instead, we rely on anonymous or pseudonymous forms of data, such as IP addresses, general geo-location information, and unique identifiers about Internet users, and do not attempt to associate this data with other data that can be used to identify real people. However, this type of information is considered "personal" across various jurisdictions and is governed by an increasing number of consumer privacy laws and regulations.

Data collection, use, and disclosure by companies that do not have direct relationships with the consumers whose personal data they process are now subject to state data broker laws, including in California, Oregon, and Texas. Notably, California's Delete Act, dramatically increases obligations and potential penalties relative to the state’s preexisting data broker statute, including by requiring us to integrate with the state’s to-be-released Deletion Request and Opt-out Platform ("DROP") and delete personal data submitted through DROP mechanisms.

There are also a number of specific laws and regulations governing the collection and use of certain types of consumer data relevant to our business. For example, the Children’s Online Privacy Protection Act ("COPPA"), imposes restrictions on the collection and use of data about users of child-directed websites. Other regulators and lawmakers continue to focus on activities involving data perceived as particularly sensitive such as data based on race, ethnicity or health information.

In the European Economic Area ("EEA") member states and the United Kingdom (“UK”), the use and transfer of personal data is governed by the General Data Protection Regulation and the UK General Data Protection Regulation (the "GDPR" and "UK GDPR"). The GDPR and UK GDPR set out significant potential liabilities for certain data protection violations and establish significant regulatory requirements resulting in a greater compliance burden for us in the course of delivering our solution in the EEA and UK.

In addition to the GDPR and UK GDPR, other regions have begun to promulgate data protection laws and reforms, including India and Australia, and state lawmakers in the United States continue to actively focus on consumer privacy regulations, with a total of 20 comprehensive state privacy laws in effect as of the end of 2025. These laws have caused, and will likely continue to cause, us to incur additional compliance costs and impose additional restrictions on us and on our industry partners. Additionally, our compliance with our privacy policies and our general consumer privacy practices are also

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subject to review by the Federal Trade Commission and certain State Attorneys General. Outside of the United States, our privacy and data practices are subject to regulation by data protection authorities and other regulators in the countries in which we do business.

In the EU, in addition to privacy laws, our business is also subject to further digital regulation such as the Digital Services Act ("DSA"). The DSA establishes further transparency requirements concerning the use of data for profile-based advertising that may result in new compliance obligations and sets out significant fines in case of a violation.

Beyond laws and regulations, we are members of self-regulatory bodies that set out best practices, principles and codes of conduct related to the collection, use, and disclosure of consumer data, including the Internet Advertising Bureau ("IAB"), the Digital Advertising Alliance, the Network Advertising Initiative, and the Europe Interactive Digital Advertising Alliance. We provide consumers with notice via our privacy policy about our use of cookies and other technologies to collect consumer data, and of our collection and use of consumer data to deliver personalized advertisements. We allow consumers to opt-out or withdraw consent from the use of data we collect for purposes of behavioral advertising through a mechanism on our website, linked through our privacy policy as well as through portals maintained by some of these self-regulatory bodies.

We support privacy initiatives and believe they will be beneficial to consumers' confidence in advertising technology, which will ultimately be positive for the advertising ecosystem in the long term. However, until prevailing compliance practices standardize, the impact of worldwide privacy regulations on our business and, consequently, our revenue could be negatively impacted.

For additional information regarding regulatory risks to our business, see "Item 1A. Risk Factors."

Seasonality

Our revenue, Contribution ex-TAC, cash flow from operations, Adjusted EBITDA, operating results, and other key operating and financial measures may vary from quarter to quarter due to the seasonal nature of buyer spending. For example, many buyers devote a disproportionate amount of their advertising budgets to the fourth quarter of the calendar year to coincide with increased holiday purchasing. We expect our revenue, cash flow, operating results and other key operating and financial measures to fluctuate based on seasonal factors from period to period and expect these measures to be higher in the fourth quarter than in other quarters. Refer to "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations” for additional information related to key operating and financial performance Metrics.

Available Information

The Company is subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and accordingly files Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, proxy statements, and related amendments and other information with the U.S. Securities and Exchange Commission, or the SEC, pursuant to Sections 13(a) and 15(d) of the Exchange Act. Information filed by the Company with the SEC is available free of charge on the Company’s website at investor.magnite.com as soon as reasonably practicable after such materials are filed with or furnished to the SEC.

Item 1A. Risk Factors

Investing in our common stock involves a high degree of risk, including the risks described below, each of which may be relevant to decisions regarding an investment in or ownership of our stock. The occurrence of any of these risks could have a significant adverse effect on our reputation, business, financial condition, revenue, results of operations, growth, or ability to accomplish our strategic objectives, and could cause the trading price of our common stock to decline. You should carefully consider the risks set forth below and the other information contained in this report, including our consolidated financial statements and related notes and Management's Discussion and Analysis of Financial Condition and Results of Operations, before making investment decisions related to our common stock. However, this report cannot anticipate and fully address all possible risks of investing in our common stock, the risks of investing in our common stock may change over time, and additional risks and uncertainties that we are not aware of, or that we do not consider to be material, may emerge. Moreover, some of the factors, events, and contingencies discussed below may have occurred in the past. References to past events are provided by way of example only and are not intended to be a complete listing or representation as to whether or not such events have occurred in the past or their likelihood of occurring in the future, and instead reflect our beliefs and opinions as to the factors, events, or contingencies that could materially and adversely affect us in the future. Accordingly, you are advised to consider additional sources of information and exercise your own judgment in addition to the information we provide.

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Risks Related to Our Business, Growth Prospects and Operating Results

Our revenue and operating results are highly dependent on the overall demand for advertising and any macroeconomic challenges may adversely affect our business, financial position, results of operations and/or cash flows.

Our business depends on the overall demand for advertising and on the economic health of our current and prospective sellers and buyers. If advertisers reduce their overall advertising spending, our revenue and results of operations are directly affected. Accordingly, our business and operations have been, and could in the future be, adversely affected by events beyond our control, such as health epidemics or pandemics, geopolitical events, and economic and macroeconomic factors like labor strikes, labor shortages, supply chain disruptions, tariffs, trade wars, capital market disruptions and instability of financial institutions, inflation and recessionary concerns impacting the markets and communities in which our clients operate.

In addition, continued inflation could result in an increase in our cost base relative to our revenue and increased cost associated with our infrastructure investments. Moreover, in response to US tariffs, foreign countries in which we operate may enact additional or new taxes that are applicable to our business.

Any worsening of macroeconomic conditions in future periods would likely have a negative effect on our financial results, the magnitude of which is difficult to predict.

We operate in an intensely competitive market that includes companies that have greater financial, technical and marketing resources than we do.

We face intense competition in the marketplace. We compete for advertising spending against competitors that, in some cases, are also buyers and/or sellers on our platform. We also compete for supply of advertising inventory against a variety of competitors. Some of our existing and potential competitors are better established, benefit from greater name recognition, may have offerings and technology that we do not have or have significantly more financial, technical, sales, and marketing resources than we do. In addition, some competitors, particularly those with greater scale or a more diversified revenue base and a broader offering, have greater flexibility than we do to compete aggressively on the basis of price and other contract terms, or to compete with us by including in their product offerings services that we may not provide. Some existing and potential buyers that we work with have their own direct relationships with sellers or are seeking to establish such relationships, and many sellers are investing in capabilities that enable them to connect more effectively directly with buyers without the use of intermediaries such as us. Our business suffers to the extent that buyers and sellers purchase and sell advertising inventory directly from one another or through intermediaries other than us, reducing the amount of advertising spend on our platform. New or stronger competitors may emerge through acquisitions and industry consolidation or through development of disruptive technologies, including artificial intelligence (“AI”), which may disrupt the digital advertising ecosystem by enabling new ad-buying, optimization or monetization models or enhancing the capabilities of competitors. If our offerings are not perceived as competitively differentiated, we could lose clients, market share or be compelled to reduce our prices, making it more difficult to grow our business profitably.

There has been rapid evolution and consolidation in the advertising technology industry, and we expect these trends to continue, thereby increasing the capabilities and competitive posture of larger companies, particularly those that are already dominant in various ways, and enabling new or stronger competitors to emerge. There is a finite number of large buyers and sellers in our target markets, and any consolidation of buyers or sellers may give the resulting enterprises greater bargaining power or result in the loss of buyers and sellers that use our platform, and thus reduce our potential base of buyers and sellers, each of which would lead to erosion of our revenue.

As technology continues to improve and market factors continue to attract investment, competition and pricing pressure may increase and market saturation may change the competitive landscape in favor of larger competitors with greater scale and broader offerings, including those that can afford to spend more than we can to grow more quickly and strengthen their competitive position. Competition may be further impacted by advancements in AI, and our ability to compete in the future may be dependent, in part, on our ability to further develop AI into our solutions. In addition, our competitors or potential competitors may adopt certain aspects of our business model, which could reduce our ability to differentiate our solutions.

For all of these reasons, we may not be able to compete successfully against our current and future competitors.

Our contracts with buyers and sellers are generally not exclusive, may be terminated upon relatively short notice, and generally do not require minimum volumes or long-term commitments. If buyers or sellers representing a significant portion of the demand or inventory in our marketplace decide to materially reduce the use of our solution, we could experience an immediate and significant decline in our revenue and profitability and harm to our business.

Generally, our buyers and sellers are not obligated to provide us with any minimum volumes of business, may do business with our competitors as well as with us, may reduce or cancel their business with us or terminate our contracts without penalty, and may bypass us and transact directly with each other or through other intermediaries that compete with us. Accordingly, our business is highly vulnerable to changes in the macro environment, price competition, and development of

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new or more compelling offerings by our competitors, which could reduce business generally or motivate buyers or sellers to migrate to competitors’ offerings.

Sellers and buyers may seek to change the terms on which they do business with us, or allocate their advertising inventory or demand to our competitors who provide advertising demand and supply to them on more favorable terms or whose offerings are considered more beneficial. Supply of advertising inventory is also limited for some sellers, and sellers may request higher prices, fixed price arrangements or guarantees that we cannot provide as effectively as our competitors, or that would reduce the profitability of that business. In addition, sellers sometimes place significant restrictions on the sale of their advertising inventory, such as strict security requirements, limitations on data sharing, prohibitions on advertisements from specific advertisers or specific industries, and restrictions on the use of specified creative content or format. Buyers, in turn, are free to direct their spend to us or one or more of our competitors, and increasingly are seeking price concessions, rebates, or other consideration to direct more spend towards us.

We serve many buyers and sellers, but certain large buyers and sellers have accounted for and will continue to account for a disproportionate share of business transacted through our solution. In 2025, there were two buyers of advertising inventory that indirectly contributed to approximately 44% of revenue through their buying activity from sellers on our platform. If a buyer or group of buyers representing a significant portion of the demand in our marketplace, or a seller or group of sellers representing a significant portion of the inventory in our marketplace decides to materially reduce use of our solutions, it could cause an immediate and significant decline in our revenue and profitability and harm to our business. In addition, loss of substantial inventory or demand could degrade our marketplace. Loss of major DSP sources of demand could adversely affect bid density or pricing in our auctions, and reduction in fees if we are not able to redirect inventory to other demand sources. Loss of important unique inventory could reduce fees from demand that cannot be shifted to other sellers and make it harder to differentiate ourselves from our competitors. The number of large media buyers and sellers in the market is finite, and it could be difficult for us to replace the losses from any buyers or sellers whose relationships with us diminish or terminate.

If CTV advertising spend grows more slowly than we expect, or growth occurs disproportionately through platforms that we cannot access, our operating results and growth prospects could be harmed.

The growth of our business is dependent, in part, on the continued growth in CTV advertising spend. Growth in the CTV advertising market is dependent on a number of factors, including the pace of user adoption, the continued proliferation of digital content and CTV providers, the adoption of ad-supported models by CTV sellers in lieu of, or in addition to, subscription models, and an acceleration in the shift of ad dollars from traditional linear TV to CTV to keep pace with changing viewership habits.

In addition, it is possible that CTV advertising spend growth may be disproportionately focused on CTV sellers that do not utilize our solution, which could impact our ability to grow our business in line with industry growth rates.

If the market for ad-supported CTV develops more slowly than we expect or fails to develop our operating results and growth prospects could be harmed. In addition, to the extent that CTV advertising spend growth is concentrated among inventory that is not available to us or not available on favorable terms it could hurt our overall growth prospects.

Programmatic advertising presents unique challenges for CTV sellers, and CTV sellers may not adopt or may be slow to adopt programmatic solutions that transact in biddable auction environments.

As digital advertising has continued to scale and evolve, the amount of advertising being bought and sold programmatically has increased dramatically. Although programmatic represents a substantial majority of CTV advertising, CTV sellers have generally been more cautious to adopt programmatic solutions compared to desktop and mobile video sellers, and in particular, with respect to biddable auctions.

Many CTV sellers have backgrounds in cable or broadcast television and have limited experience with digital advertising, and in particular programmatic advertising. For these sellers, it is extremely important to protect the quality of the viewer experience to maintain brand goodwill and ensure that online advertising efforts do not create sales channel conflicts or otherwise detract from their direct sales force. In this regard, programmatic advertising presents a number of potential challenges, including the ability to ensure that ads are brand safe, comply with business rules around competitive separation, are not overly repetitive, are played at the appropriate volume and do not cause delays in load-time of content.

In light of these challenges, programmatic CTV has largely been transacted through reserve auctions. Reserve auctions allow publishers to establish direct deals with a buyer, and may be "guaranteed," where a buyer has negotiated a pre-established price and volume with a seller. These transaction types allow the seller to maintain tighter control over their advertising allocation and are often used by sellers that maintain a direct sales force but still want to experience the benefits of automation. In general, advertising impressions monetized through reserve auctions carry a lower fee than impressions monetized through auctions with multiple bidders. Accordingly, an increase in the percentage of CTV inventory monetized through reserve auctions, at the expense of biddable auctions, could drive a decrease in our overall take rate (our fee as a percentage of advertising spend) which may negatively impact our growth.

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While we believe that CTV sellers will begin to expand their use of biddable inventory to attract a more diverse array of advertisers, there can be no assurance that CTV sellers will adopt such solutions or guarantees regarding the speed at which they may adopt such solutions. Any such failure or delay in adoption could negatively impact our finance results and growth prospects.

We may not be able to maintain or increase access to the CTV advertising inventory monetized through our platform on terms acceptable to us, and our efforts to maintain such access may subject us to an increased risk of losses.

Our success requires us to maintain and expand our access to premium and unique advertising inventory. We do not own or control the ad inventory upon which our business depends and do not own or create content. Sellers are generally not required to offer a specified level of inventory on our platform, and we cannot be assured that any publisher will continue to make their ad inventory available on our platform. Sellers may seek to change the terms on which they offer inventory on our platform, including with respect to pricing, may elect to make advertising inventory available to our competitors who offer more favorable economic terms, may create their own ad-tech solutions, or may connect with buyers directly. Sellers may also require us to take increased risks in some of our commercial agreements in the form of offering revenue guarantees or minimum spend commitments, and we may be subject to losses if we cannot meet these guarantees or commitments. Furthermore, sellers may enter into exclusive relationships with our competitors or with DSPs directly, which may limit us from offering their inventory.

These risks are particularly pronounced with CTV sellers. CTV inventory is highly sought after, and unlike desktop or mobile advertising, which may come from disparate sources, CTV inventory tends to be concentrated on a smaller number of larger sellers that enjoy significant negotiating leverage. In addition, CTV sellers may be more likely to rely on proprietary technology to power their ad business given their additional resources. This dynamic has been exacerbated by consolidation in the industry, as a number of digital-first CTV sellers have been acquired by larger established television and media brands. We expect consolidation to continue among CTV sellers, and in some instances this consolidation may result in the loss of business with an existing client (for example, if an acquiror has a preferred relationship with one of our competitors or has a proprietary solution). Because of the concentration among CTV sellers, the loss of a CTV client may result in a significant decrease in the amount of CTV inventory available through our platform. Any decrease in our ability to access CTV inventory could negatively impact our results, as we view CTV revenue as a key differentiator and driver for our growth.

The digital advertising market, and our business, may be negatively impacted by advancements in AI.

Advancements in AI present both opportunities and risks to our business, particularly within the context of the open internet and display advertising. AI is changing the way in which users access information and content on the open internet, in particular with respect to search referral traffic, which has and is expected to continue to decline. This shift could create challenges for open web publishers that have relied on advertising to support their business models. Furthermore, the rapid evolution of AI technologies could lead to diminishing demand for display advertising or reallocating budgets to new formats and approaches, including walled-gardens that we cannot access. If we are unable to capture this demand through other channels, adapt to evolving market expectations, or compete effectively with AI-driven ecosystems, our growth and market position could be adversely impacted.

AI may significantly affect the competitive dynamics of our industry, and failure to effectively build AI features into our platform could adversely affect our results of operations.

The market for programmatic advertising is characterized by rapid technological change and intense competition. We face significant pressure from existing competitors and new market entrants who are increasingly leveraging AI to enhance their platforms. If our competitors or other third parties, including those with greater financial and technical resources, incorporate AI into their offerings more quickly or effectively than we do, our platform may become less attractive to buyers and sellers of digital advertising. Any failure on our part to successfully develop and deploy AI solutions into our platform could result in a loss of market share.

Moreover, emerging AI–driven programmatic advertising protocols and transaction frameworks may not be interoperable with, or may reduce reliance on, existing industry standards and infrastructure, which could disrupt established buying and selling workflows. If we are unable to adapt our technology or influence the adoption of such protocols, it could adversely affect demand for our platform and our market share. If we fail to anticipate and adequately respond to these AI-driven structural shifts, our competitive position and ability to maintain a leading independent marketplace may be compromised.

We may be ineffective in using AI to realize internal efficiencies, which could result in higher operating costs and decreased margins.

We currently incorporate AI solutions into our product offerings and internal workflows, and we expect the use of AI to become increasingly central to our operations over time. However, our ability to realize the anticipated benefits of these

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technologies is subject to significant risks and uncertainties. We may fail to effectively leverage internal AI solutions to automate manual processes, optimize our infrastructure or enhance the productivity of our team.

If we are unable to realize the cost savings or operational improvements we anticipate from AI, our margins may be negatively impacted. Furthermore, the implementation of AI-driven internal tools requires significant investment in talent and infrastructure; if these investments do not yield a corresponding increase in productivity or a reduction in legacy costs, our financial condition and results of operations could be adversely affected. Additionally, any over-reliance on AI for critical business functions without adequate human oversight could lead to operational errors, data inaccuracies, or inefficiencies that could harm our reputation and competitive position.

The regulatory landscape governing AI is still developing, and our use of third party AI tools may result in increased legal and regulatory scrutiny, litigation, and reputational harm.

The regulatory landscape governing AI is highly uncertain and rapidly evolving. We face potential risks from new or enhanced governmental oversight and evolving legal standards regarding the use of AI.

The integration of third-party AI models with our products and services relies on certain safeguards implemented by the third-party developers of the underlying AI models. If the content, analyses, or recommendations that AI applications assist in producing are or are alleged to be inaccurate, deficient, or biased, our business and reputation may be adversely affected.

Additionally, AI applications generally state they do not use personal data or other classes of protected data, but we may not know the source of data used by an AI application and may inadvertently incorporate personal information, or data derived from personal data, in the course of using an AI application. Any such inclusion could lead to violations of global privacy laws, such as the GDPR or CCPA, and result in significant fines or legal action.

The use of AI also presents unique cybersecurity and intellectual property risks. Our use of AI tools could lead to cybersecurity incidents or the unauthorized public disclosure of our intellectual property. Moreover, malicious actors may increasingly use AI to develop more sophisticated and automated cyberattacks against our infrastructure.

If we are unable to minimize unintended harmful impacts of AI or fail to adapt to new AI-specific regulations, our competitive position and financial condition may be materially and adversely affected.

We may be unsuccessful in our Supply Path Optimization efforts.

Supply path optimization refers to efforts by buyers to consolidate the number of vendors with which they work to find the most effective and cost-efficient paths to procure media. There are a number of criteria that buyers use to evaluate supply partners. While we believe we are well positioned to benefit from supply path optimization in the long run as a result of our transparency, our pricing tools, which reduce the overall cost of working with us, our broad and unique inventory supply across all channels and formats, buyer tools such as traffic shaping that reduce the cost of working with us, and our brand safety measures, we compete for demand with a number of well-established companies, and we must continue to adapt and improve our offerings to win buyers' business.

In addition, in order to achieve increased advertising spend or prevent loss of business to a competitor, we may negotiate discounts, rebates, or similar incentives with advertisers or agencies, which we may be unable to recoup. We believe that because our business has many fixed costs, increases in advertising spend volume generally create opportunities to disproportionately improve our bottom line results, even with increased discounts, rebates or other buyer incentives. However, our results could be negatively impacted by discounts, rebates and other buyer incentives, notwithstanding an increase in ad spend.

Our technology development efforts may be inefficient or ineffective, which may impair our ability to attract buyers and sellers.

We face intense competition in the marketplace and are confronted by rapidly changing technology (including advancements in AI), evolving industry standards and consumer needs, regulatory changes, and the frequent introduction of new solutions by our competitors to which we must adapt and respond. Our future success will depend in part upon our ability to enhance our existing solution and to develop and introduce competing new solutions in a timely manner with features and pricing that meet changing client and market requirements. Our solutions are complex and require a significant investment of time and resources to develop, test, introduce, and enhance. We schedule and prioritize our development efforts according to a variety of factors, including our perceptions of market trends, client requirements, and resource availability; however, we may encounter unanticipated difficulties that require us to re-direct, scale back, or modify our efforts. If development of our solution becomes significantly more expensive due to changes in regulatory requirements or industry practices, or other factors, we may find ourselves at a disadvantage to larger competitors with more resources to devote to development. These factors place significant demands upon our engineering organization, require complex planning, and can result in acceleration of some initiatives and delay of others. We use outsourced software development for certain development efforts, which may put the company at greater risk with respect to our technology development because we may have less control over the performance of outside programmers and we may be at greater risk of losing their services. To the extent we do not manage our development

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efforts efficiently and effectively, we may fail to produce solutions that respond appropriately to the needs of buyers and sellers, and competitors may more successfully develop responsive offerings. If our solution is not competitive, buyers and sellers can be expected to shift their business to competing solutions. Buyers and sellers may also resist adopting our new solutions for various reasons, including reluctance to disrupt existing relationships and business practices or to invest in necessary technological integration. Clients, vendors, and competitors may also react negatively to the announcement of new products and offerings, which may have a harmful effect on our relationships and our business.

We must increase the scale and efficiency of our technology infrastructure to support our growth and transaction volumes.

Our technology must scale to process the increased ad requests on our platform. For each ad request that we process we incur infrastructure costs regardless of whether that ad request is ultimately monetized through our platform. The number of ad requests that we process has grown significantly in order to support additional ad spend on our platform, in particular with respect to CTV sellers who operate at large scale and experience spikes in viewership.

We must continue to increase the capacity of our platform to support the growth of our business and an increasing variety of advertising formats and platforms. Additionally, we must maintain a stable service infrastructure and reliable service delivery. To the extent we are unable, for cost or other reasons, to effectively increase the capacity of our platform, continue to process transactions at fast enough speeds, and support emerging advertising formats or services preferred by buyers, our revenue will suffer. Furthermore, failure to optimize and manage infrastructure costs efficiently could result in margin compression and increased financial strain.

We expect to continue to invest in our platform to meet increasing volume, including investments in on-prem data centers to support a higher percentage of our transactions. Such investment may negatively affect our profitability and results of operations. Additionally, any unexpected surges in traffic, inefficiencies in scaling, or disruptions to our infrastructure could degrade platform performance, harm our reputation, and cause us to lose business to competitors with more resilient or cost-effective solutions.

The emergence of header bidding has increased competition from other demand sources and may cause infrastructure strain and added cost.

In the mobile and desktop channels, the vast majority of sellers have embraced header bidding technology, a solution by which impressions that would have previously been exposed to different potential sources of demand in a sequence dictated by ad server priorities are instead available for concurrent competitive bidding by demand sources. This can help sellers increase revenue by exposing their inventory to more bidders, thereby allocating more inventory to demand sources that value it most highly. While header bidding has increased our access to certain pools of inventory that otherwise would have been allocated first to other exchanges, thus increasing our revenue opportunity, it has also resulted in a number of challenges for our business. For instance, some sellers may choose not to integrate with us as a header-bidding demand source, or may prioritize other sources of demand, including owners of the header bidding solutions, leaving us at a competitive disadvantage in the auction. In addition, header-bidding has vastly increased the volume of ad requests that need to be processed and analyzed through our system, resulting in increased infrastructure costs.

If we are unable to improve the efficiency and effectiveness of our header bidding solutions and installations, we may not fully offset these increased infrastructure costs, and we will not be able to take full advantage of the opportunities made available through current header bidding technology to access a larger addressable market and increase our revenue by capturing a greater share of inventory. In addition, our success in monetizing impressions through header-bidding solutions is dependent on the interoperability of our platform with proprietary header-bidding solutions, some of which are owned by our competitors, including Google. As a result, we may be susceptible to evolution in technology and changes in business practices by the owners of such header-bidding solutions that we cannot predict.

To the extent our access to mobile inventory is limited by third-party technology or lack of direct relationships with mobile sellers, our ability to grow our business will be impaired.

Our success in the mobile channel depends upon the ability of our technology solution to provide advertising for most mobile-connected devices, as well as the major operating systems or internet browsers that run on them and the thousands of applications that are downloaded onto them. The design of mobile devices and operating systems, applications, or internet browsers is controlled by third parties. These parties frequently introduce new devices and applications, and from time to time they may introduce new operating systems or internet browsers or modify existing ones in ways that may significantly affect our business, such as by providing ad-blocking capabilities or by limiting access to Internet user data. Network carriers may also affect the ability to access specified content on mobile devices. To the extent our solution is unable to work on these devices, operating systems, applications, or internet browsers for any reason, our ability to generate revenue through mobile advertising is significantly impaired, and that impairment may be material.

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We expect mobile applications to be the largest driver of our mobile business. Many mobile apps utilize software development kits, or SDKs, and other proprietary technology of third parties, such as aggregators, and it is those third parties, not the application providers themselves, that contract with us to provide exchange services to help monetize the inventory. Due to this consolidation, if our relationships with these third parties decline or are terminated, it may result in a larger than usual loss of access to mobile inventory. Moreover, while we have introduced our own mobile in-app SDK, we cannot be sure that our development efforts will be successful or that our solution will assist us in accessing mobile inventory. Any rapid and/or significant decline in the availability of mobile inventory can adversely affect our mobile advertising spend and growth prospects.

Fee issues have in the past and could in the future have a material adverse effect on our business.

A majority of our revenue comes from buyers purchasing advertising inventory made available by sellers on our platform. We experience requests from buyers for discounts, fee concessions or revisions, rebates or other forms of consideration, refunds, and greater levels of pricing transparency and specificity, in some cases as a condition to maintain the relationship or to increase the amount of advertising spend that the buyer sends to our platform. In addition, we charge fees to sellers for use of our technology, typically as a percentage of the cost of media, and we may decide to offer discounts or other pricing concessions in order to attract more inventory or demand, or to compete effectively with other providers that have different or lower pricing structures and may be able to undercut our pricing due to greater scale or other factors.

These fee concessions may be more prevalent among CTV publishers where inventory is scarce and concentrated among large sellers with significant negotiating leverage. Moreover, the majority of CTV transactions are currently executed through reserve auctions. Reserve auctions generally involve lower fees than we can charge for auction transactions and we may experience additional fee pressure as more competitors, including new entrants as well as sellers themselves, build their own technology and infrastructure to enable reserve auctions.

Our revenue and profitability could be adversely affected if we are forced to make significant fee concessions, rebates, or refunds, or if buyers reduce spending with us or sellers reduce inventory available through our exchange due to fee disputes or pricing issues.

Our take rates may be difficult to forecast and may decrease in future periods; any decrease in our take rates may result in a decrease in our revenue notwithstanding an increase in the amount of spend transacted through our platform.

We generate revenue through our platform on a transactional basis where we are paid by a publisher each time an impression is monetized on our platform. Typically, this fee is structured as a percentage of advertising spend that the publisher receives for its inventory. Our take rate varies by publisher and transaction type. For instance, our take rate tends to be lower for reserve auctions compared to auctions with multiple bidders, and tends to be lower on CTV transactions compared to other channels. Additionally, take rates tend to be higher for our managed service business where we are responsible for delivering a campaign at a fixed price. Our managed service business has been declining as a percentage of our revenue on a year-over-year basis, and we expect this trend to continue. Should our managed service business continue to decline, we may experience a shift in revenue composition, and our overall financial performance could be affected, particularly if we are unable to offset any potential revenue loss with increased adoption of our programmatic solutions. We may also negotiate lower take rates with large sellers to win additional business or share of inventory, and these sellers may account for a disproportionately higher percentage of advertising spend on our platform.

As a result of these factors, even if we are able to accurately forecast the anticipated total advertising spend transacted by buyers across our platform, we may have limited visibility regarding the revenue or Contribution ex-TAC (as defined in section "Key Operating and Financial Performance Metrics") we will generate. Any decrease in our take rate could cause our revenue and Contribution ex-TAC to decrease, notwithstanding an increase in the total spend transacted through our seller platform.

We have a history of losses and we face many risks that may prevent us from achieving or sustaining profitability in the future.

We reported net income of $144.6 million and $22.8 million during the years ended December 31, 2025 and December 31, 2024, respectively, and net loss of $159.2 million during the year ended December 31, 2023. As of December 31, 2025, we had an accumulated deficit of $516.6 million. We have implemented strategic plans designed to improve our financial performance and continue to increase revenue, and have taken steps to reduce unnecessary expenses and redirect spending to areas we expect to produce higher growth; however, these plans and steps may ultimately prove to be unsuccessful.

Notwithstanding these measures, revenue could decrease due to competitive pressures, maturation of our business, macroeconomic or other factors, and additional cost-reduction measures may be required even as we must continue to increase investment in technology in response to industry developments and to retain competitiveness. We may not be able to sustain growth or to achieve or sustain profitability in the future.

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Our business and the businesses of our advertiser clients may be subject to sales and use tax, value-added/goods and services, advertising, digital services, withholding and other taxes.

The application of sales and use tax, goods and services tax, business tax and gross receipt tax on our digital services is complex and evolving. In general, sales of tangible personal property are subject to sales and use tax unless a specific exemption applies, while services generally are not subject to sales tax unless specifically enumerated. Advertising services are considered a service and are generally not subject to sales and use tax, except in certain states. Additionally, Maryland adopted a tax on gross revenues from digital advertising. While the law is being challenged in the courts, the law took effect and we are technically subject to the tax, which increases our cost of doing business. Other states are looking to follow suit and tax either digital advertising or other goods or services. In addition, the continual evolution of our services and the expansion of our business offerings may further complicate the determination of the sales taxability of our services in certain jurisdictions.

As a result of various factors, our operating results have in the past and may in the future fluctuate significantly, be difficult to predict, and fall below analysts' and investors' expectations.

Our operating results are difficult to predict, particularly because we generally do not have long-term contracts with buyers or sellers. We have experienced significant variations in revenue and operating results from period to period, and operating results may continue to fluctuate and be difficult to predict due to a number of factors, including:

•seasonality in demand for digital advertising, as many advertisers devote a disproportionate amount of their advertising budgets to the fourth quarter of the calendar year;

•changes in pricing of advertising inventory or pricing for our solution and our competitors' offerings, including potential further reductions in our pricing and overall take rate, uncertainty regarding rate of adoption, changes in the allocation of demand spend by buyers, changes in revenue mix, auction dynamics, pricing discussions or negotiations with clients and potential clients, and other factors;

•the variability and unpredictability of our managed service business, which depends on seasonal advertising trends and discretionary advertising budgets, and are typically tied to one-off or seasonal campaigns rather than recurring revenue models;

•diversification of our revenue mix to include new services, some of which may have lower pricing or may cannibalize existing business;

•the effect of political advertising, which has an intermittent impact on our business depending on election cycles, and may be highly unpredictable and variable based on circumstances outside of our control;

•the effect of AI on our business;

•the addition or loss of buyers or sellers;

•the ability of buyers to integrate demand directly with sellers without the use of our platform;

•general economic conditions and the economic health of our current and prospective sellers and buyers;

•changes in the advertising strategies or budgets or financial condition of advertisers;

•the performance of our technology and the cost, timeliness, and results of our technology innovation efforts;

•advertising technology and digital media industry conditions and the overall demand for advertising, or changes and uncertainty in the regulatory environment for us or buyers or sellers, including with respect to privacy regulation;

•the introduction of new technologies or service offerings by our competitors and market acceptance of such technologies or services;

•the phasing out of third-party cookies throughout the industry;

•our level of expenses, including investment required to support our technology development, scale our technology infrastructure and business expansion efforts, including acquisitions, hiring and capital expenditures, or expenses related to litigation;

•the impact of changes in our stock price on valuation of stock-based compensation or other instruments that are marked to market;

•the effectiveness of our financial and information technology infrastructure and controls;

•geopolitical and social factors, such as concerns regarding negative, unstable or changing economic conditions in the countries and regions where we operate, global and regional recessions, political instability, and trade disputes;

•foreign exchange rate fluctuations; and

•changes in accounting policies and principles and the significant judgments and estimates made by management in the application of these policies and principles.

Because significant portions of our expenses are relatively fixed, variation in our quarterly revenue can cause significant variations in operating results and resulting stock price volatility from period to period. Period-to-period comparisons of our historical results of operations are not necessarily meaningful, and historical operating results may not be

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indicative of future performance. If our revenue or operating results fall below the expectations of investors or securities analysts, or below any guidance we may provide to the market, the price of our common stock could decline substantially.

Any acquisitions we undertake in the future may disrupt our business, adversely affect operations, dilute stockholders, and expose us to costs and liabilities, and we may not achieve the anticipated benefits or synergies of such transactions.

Acquisitions have been an important element of our business strategy. Moreover, we may pursue future acquisitions in an effort to increase revenue, expand our market position, add to our service offering and technological capabilities, respond to dynamic market conditions, or for other strategic or financial purposes. However, there is no assurance that we will identify suitable acquisition candidates or complete any acquisitions on favorable terms, or at all. Further, any acquisitions we do complete would involve a number of risks, which may include the following:

•the identification, acquisition, and integration of acquired businesses require substantial attention from management. The diversion of management's attention and any difficulties encountered in the integration process could hurt our business;

•the identification, acquisition, and integration of acquired businesses requires significant investment, including to determine which new service offerings we might wish to acquire, harmonize service offerings, expand management capabilities and market presence, and improve or increase development efforts and technology features and functions;

•the anticipated benefits from the acquisition may not be achieved, including as a result of loss of clients or personnel of the target, other difficulties in supporting and transitioning the target's clients, the inability to realize expected synergies from an acquisition, or negative organizational cultural effects arising from the integration of new personnel;

•we may face difficulties in integrating the personnel, technologies, solutions, operations, and existing contracts of the acquired business;

•we may fail to identify all of the problems, liabilities or other shortcomings or challenges of an acquired company, technology, or solution, including issues related to intellectual property, solution quality or architecture, income or other taxes and other regulatory compliance practices, revenue recognition or other accounting practices, or employee or client issues;

•to pay for future acquisitions, we could issue additional shares of our common stock or pay cash. Issuance of shares would dilute stockholders. Use of cash reserves could diminish our ability to respond to other opportunities or challenges. Borrowing to fund any cash purchase price would result in increased fixed obligations and could also include covenants or other restrictions that would impair our ability to manage our operations;

•acquisitions expose us to the risk of assumed known and unknown liabilities including contract, tax, regulatory or other legal, and other obligations incurred by the acquired business or fines or penalties, for which indemnity obligations, escrow arrangements or insurance may not be available or may not be sufficient to provide coverage;

•new business acquisitions can generate significant intangible assets that result in substantial related amortization charges and possible impairments;

•the operations of acquired businesses, or our adaptation of those operations, may require that we apply revenue recognition or other accounting methodologies, assumptions, and estimates that are different from those we use in our current business, which could complicate our financial statements, expose us to additional accounting and audit costs, and increase the risk of accounting errors;

•acquired businesses may have insufficient internal controls that we must remediate, and the integration of acquired businesses may require us to modify or enhance our own internal controls, in each case resulting in increased administrative expense and risk that we fail to comply with the requirements of Section 404 of the Sarbanes-Oxley Act of 2002 (the "Sarbanes-Oxley Act");

•acquisition of businesses based outside the United States would require us to operate in foreign languages and manage non-U.S. currency, billing, and contracting needs, comply with laws and regulations, including labor laws and privacy laws that in some cases may be more restrictive on our operations than laws applicable to our business in the United States; and

•acquisitions can sometimes lead to disputes with the former owners of the acquired company, which can result in increased legal expenses, management distraction and the risk that we may suffer an adverse judgment if we are not the prevailing party in the dispute.

We must provide value to both buyers and sellers of advertising without being perceived as favoring one over the other or being perceived as competing with them through our service offerings.

We are interposed between buyers and sellers, and to be successful, we must continue to find ways of providing value to both without being perceived as favoring one at the expense of the other. For example, our proprietary auction algorithms, which are designed to improve auction outcomes, influence the allocation and pricing of impressions and must do so in ways that add value to both buyers and sellers. Continued technological evolution in the availability and use of more data to inform buying and selling decisions necessitates that we, as an intermediary, use data in a manner that complies with the expectations

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of both our seller and buyer clients. Furthermore, because new business models continue to emerge, we must constantly adapt our relationship with buyers and sellers and how we market ourselves to each. Consistent with our goal of connecting buyers and sellers, we seek to grow our connections to each, and we must take care that our deeper connections with buyers, on the one hand, or sellers, on the other hand, do not come at the expense of the other's interests. In addition, as our own capabilities evolve, we may be perceived by clients, particularly buyers, as competing with them, which could result in a loss of their business or otherwise negatively impact our relationships. For instance, ClearLine, a self-service buying tool that provides agencies direct access to premium advertising on our platform helps agencies maximize the spend going towards working media, makes it easier for sellers and agencies to securely share data, improves workflow for campaigns traditionally transacted manually, and helps publishers generate more revenue and develop new sources of unique demand. If we fail to balance our clients' interests appropriately, our ability to provide a full suite of services and our growth prospects may be compromised.

We rely on buyers to purchase advertising on behalf of advertisers. Such buyers may have or develop high-risk credit profiles or pay slowly, which may result in credit risk to us or require additional working capital to fund our accounts payable. In addition, direct billing arrangements between buyers and sellers may result in unfavorable fee dynamics and increased working capital demands.

Generally, we invoice and collect from buyers the full purchase price for impressions they have purchased, retain our fees, and remit the balance to sellers. However, in some cases, we may be required or elect to pay sellers for impressions delivered before we have collected, or even if we are unable to collect, from the buyer of those impressions. There can be no assurance that we will not experience bad debt in the future, and write-offs for bad debt could have a materially negative effect on our results of operations for the periods in which the write-offs occur. This is particularly true in the case of buyers that act as technological intermediaries, such as DSPs, since those DSPs control large amounts of spend across various advertisers and agencies. In addition to posing their own credit risk, such DSPs may not be required to pay us for specific inventory in the event the DSP is not able to collect payment from the underlying advertiser directing the campaign.

In addition, we attempt to coordinate collections from our buyers so as to fund our payment obligations to our sellers. However, some buyers and sellers may require direct billing and collection arrangements between themselves, and some providers of header bidding wrappers or other downstream decisioning mechanisms in which we participate (such as Google OB) may control billing and collection for transactions we win through their platforms.

In the past, some buyers have experienced financial pressures that have motivated them to slow the timing of their payments to us. If buyers slow their payments to us or our cash collections are significantly diminished as a result of these dynamics, our revenue and/or cash flow could be adversely affected and we may need to use working capital to fund our accounts payable pending collection from the buyers. This may result in additional costs and cause us to forgo or defer other more productive uses of that working capital.

We rely on buyers and sellers to abide by contractual requirements and relevant laws, rules, and regulations when using our solution. The acts or omissions of buyers or sellers, or our own failure to meet advertising and inventory content standards and provide services that our buyers and sellers trust, could harm our brand and reputation and those of our partners, and negatively impact our business, financial condition and results of operations.

Though we contractually require buyers and sellers to abide by relevant laws, rules and regulations, as well as restrictions by their counterparties, when transacting on our platform, we do not control the content of the advertisements that we serve or the content of the websites providing the inventory, and there are many circumstances in which it is difficult or impossible for us to monitor or evaluate the compliance of our buyers and sellers. If buyers or sellers fail to abide by relevant laws, rules and regulations, or contract requirements, we could potentially face liability for such misuse.

In addition, 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 or make inventory available, respectively, without some guarantee of brand security. Consequently, our reputation depends in part on providing services that our buyers and sellers trust, and we have contractual obligations to meet content and inventory standards. We contractually prohibit the misuse of our platform by our buyers and sellers and actively monitor inventory against our quality guidelines. Despite such efforts, we may provide access to inventory that is objectionable to our buyers or serve advertising that contains objectionable content, which could harm our or our clients’ brand and reputation, decrease their trust in our platform, and negatively impact our business, financial condition and results of operations. Furthermore, we may receive public pressure to discontinue working with certain sellers or buyers on our platform and our determination whether to continue or cease working with a given client may subject us to reputational risk.

Our sales efforts with buyers and sellers may require significant time and expense and may not yield the results we seek.

Attracting new buyers and sellers and increasing our business with existing buyers and sellers involves substantial time, expense, and personnel investments, and we may not be successful in our efforts. This is particularly true with respect to our managed service business, which relies on direct relationships with advertisers, and is therefore more resource intensive. Our managed service business also tends to be more susceptible to quarterly variability, as it is typically more sensitive to seasonality and advertising budget volatility. Certain of our product offerings require a significant amount of time and costs in

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the initial client setup and implementation, and we generally do not recognize revenue from such clients until we commence services. This process can be costly and time-consuming, and is complicated by us having to spend time integrating our solution with software of buyers and sellers. If we are not successful in targeting, supporting and streamlining our sales processes, our ability to grow our business may be adversely affected. In addition, because of competitive market conditions and negotiating leverage enjoyed by large buyers and sellers, we are sometimes forced to choose between loss of business or contracting on terms that allocate more risk to us than we would prefer to accept.

Our business relationships expose us to risk of substantial liability for contract breach, violation of laws and regulations, intellectual property infringement and other losses, and our contractual indemnities and limitations of liability may not protect us adequately.

Our agreements with sellers, buyers and other third parties typically obligate us to provide indemnity and defense for losses resulting from claims of intellectual property infringement, damages to property or persons, business losses or other liabilities. Generally, these indemnity and defense obligations relate to our own business operations, obligations and acts or omissions. However, under some circumstances, we agree to indemnify and defend contract counterparties against losses resulting from their own business operations, obligations and acts or omissions, or the business operations, obligations and acts or omissions of third parties. For example, because our business interposes us between buyers and sellers in various ways, buyers often require us to indemnify them against acts and omissions of sellers, and sellers often require us to indemnify them against acts and omissions of buyers. Large indemnity obligations, or obligations to third parties not adequately covered by the indemnity obligations of our contract counterparties, could expose us to significant costs.

Our solution relies on third-party open source software components. Failure to comply with the terms of the underlying open source software licenses could expose us to liabilities, and the combination of certain open source software with code that we develop could compromise the proprietary nature of our solution.

Our solution utilizes software licensed to us by third-party authors under "open source" licenses. The use of open source software may entail greater risks than the use of third-party commercial software, as open source licensors generally do not provide warranties or other contractual protections regarding infringement claims or the quality of the code. If we combine our proprietary software with open source software in a certain manner, we could, under certain open source licenses, be required to release the source code of our proprietary software to the public. This would allow our competitors to create similar solutions with lower development effort and time and ultimately put us at a competitive disadvantage.

The terms of many open source licenses have not been interpreted by U.S. courts, and there is a risk that these licenses could be construed in a way that could impose unanticipated conditions or restrictions on us. Moreover, we cannot guarantee that our processes for controlling our use of open source software will be effective. If we are held to have breached the terms of an open source software license, we could be required to seek licenses from third parties to continue operating using our solution on terms that are not economically feasible, to re-engineer our solution or the supporting computational infrastructure to discontinue use of certain code, or to make generally available, in source code form, portions of our proprietary code.

Risks Related to Our Collection, Use and Disclosure of Data

Our business depends on our ability to collect, use, and disclose data to deliver advertisements. Any limitation imposed on our collection, use or disclosure of this data could significantly diminish the value of our solution and cause us to lose sellers, buyers, and revenue. Proliferation of consumer tools, regulatory restrictions and technological limitations all threaten our ability to use and disclose data.

The more informed advertising is about its audience, the more valuable it is. Programmatic advertising enables audience targeting based on the interests and actions of the user. Targeted advertising is generally more effective and valuable for buyers than other types of advertising, resulting in more revenue for sellers. In order to target advertising, we and our clients must collect and use data in a variety of ways. Our ability to collect, use, and disclose data about user behavior and interaction with content is critical to the value of our services, and any limitation on our data practices could impair our ability to deliver effective solutions to our clients. Any restriction on the types of data we collect could make placement of advertising through our solution less valuable, with commensurate reductions in revenue.

Consumers can, with increasing ease, implement practices or technologies that limit our ability, or that of our sellers, buyers and business partners, to collect data. For example, users may delete or block the use of cookies and similar technologies used to collect data, including through their browser or connected device settings. Consumers may also download "ad blocking" software that prevents certain cookies and other tracking technologies from being stored on a user’s computer or mobile device or from making calls to advertising partners, which may prevent the delivery of targeted or other advertisements. In addition, device manufacturers, browsers and other tools are increasingly promoting features that allow users to disable the collection of data. For example, Apple requires user opt-in before permitting access to Apple’s unique identifier, or IDFA. These shifts have had, and will likely continue to have, a substantial impact on the mobile advertising ecosystem and could harm growth in this channel.

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Laws governing the processing of personal data also continue to impact our ability to collect data. For example, Directive 2002/58/EC (as amended by Directive 2009/136/EC), commonly referred to as the ePrivacy Directive, directs EU member states to ensure that accessing personal data on an internet user’s computer, such as through cookies and similar technologies, generally requires opt in consent and is allowed only if the user has been informed about such access and given his or her opt-in consent. Further, numerous comprehensive state privacy laws across the U.S. require businesses that engage in certain advertising uses of personal data to offer and honor an opt-out of such activities, including, in some states, through browser or device-based opt-out signals, such as the Global Privacy Control (“GPC”). Similar regulations have been proposed in the EU. Use of GPC and similar user privacy features provided on other channels of programmatic advertising, such as CTV, are growing. Technical or policy changes, including regulation or industry self-regulation, could also harm our growth in those channels. As further described in the risk factors below, current and potential future privacy laws and regulations in the U.S. and abroad already restrict, and could further restrict, the ability to collect and process certain types of user data.

In addition, much of the data we collect and process belongs to our buyers or sellers, and we receive their permission to use it. Although our sellers and buyers generally permit us to aggregate and use data from advertising placements, subject to certain restrictions, sellers or buyers might decide to restrict our collection or use of their data. There could be various reasons for this, including perceptions by buyers that their data can be used by sellers to extract higher prices for impressions, or perceptions by sellers that their data can be used by buyers to bid tactically to reduce pricing for impressions. As consumers continue to increase their use of digital technology and to incorporate multiple devices into their lives, linking and using data across such devices is increasingly important. Various challenges affect our ability to link data relating to discrete devices or browsers, including different technologies, increased user awareness and sensitivity regarding use of data about their device usage, and evolving regulatory and self-regulatory standards. These challenges may slow growth, and if we are not able to cope with these challenges as effectively as other companies, we will be competitively disadvantaged. Any limitation on our ability to collect data about user behavior and interaction with content could make it more difficult for us to deliver effective solutions that meet the needs of sellers and buyers.

If third-party cookies are replaced by alternative tracking mechanisms, our performance may decline and we may lose buyers and revenue.

Industry participants in the advertising technology ecosystem have long anticipated the deprecation of third-party cookies and other identifiers, making it more difficult to rely on such technologies to identify users' devices.

Advertisers, publishers, and technology platforms are increasingly prioritizing privacy-focused solutions, and a number of industry participants have suggested alternative identity solutions. These tools, while intended to balance privacy and utility, may not fully replicate the capabilities of cookies and could disrupt established advertising workflows. Moreover, alternative identification solutions may require substantial development and commercial changes for us to support. There is also a risk that such tools will favor proprietary ad tech ecosystems potentially disadvantaging independent platforms like Magnite.

Furthermore, market dynamics may still shift as buyers explore first-party data strategies, proprietary identifiers, and other solutions that reduce reliance on cookies. This trend could favor walled gardens and platforms with extensive access to first-party data, presenting competitive challenges for companies operating within the open internet. The growing adoption of these approaches may diminish the effectiveness of our platform in attracting buyers and advertisers, potentially leading to reduced revenue and market share.

Even in the absence of third-party cookie deprecation, evolving regulatory and consumer expectations around privacy may require significant investment in re-engineering our platform and adapting to new data usage paradigms. If alternative solutions fail to deliver comparable performance or interoperability, or if they fundamentally shift the economics of digital advertising, our ability to compete effectively could be adversely impacted.

Our belief that the elimination of third-party cookies will lead to an increased use of first-party publisher data may be incorrect.

Even though third-party cookies remain supported, the programmatic ecosystem is increasingly shifting toward privacy-centric approaches that prioritize first-party data. We believe that this trend has the potential to shift the programmatic ecosystem from an identity model powered by buyers that are able to aggregate and target audiences through cookies and other tracking technologies to one enabled by sellers that have direct relationships with consumers and are therefore better positioned to obtain user data and consent for implementing first party identifiers. While we believe that our platform and scale position us well to provide the infrastructure and tools needed for a publisher-centric identity model to succeed, there is no guarantee that our efforts will lead to an increase of the use of first-party publisher segments in the ecosystem. It is also possible that the increased use of first-party publisher segments will disproportionately benefit sellers or the large walled gardens that have access to large amounts of first party data. Additionally, these changes could create some variability in our revenue across certain buyers or sellers, depending on the timing of changes and developed solutions, and even if there is an increase in the proliferation of first-party publisher segments, we may still incur substantial re-engineering costs to optimize our solution for use with such segments.

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Risks Related to Regulation

More legislation and regulation of digital businesses, including privacy and data protection regimes, could create unexpected additional costs, subject us to enforcement actions for compliance failures, or cause us to change our technology solution or business model, which may have an adverse effect on the demand for our solution.

Many local, state, federal, and international laws and regulations apply to the collection, use, retention, protection, disclosure, transfer, and other processing of data collected from and about consumers and devices, and the regulatory framework for privacy issues is evolving worldwide. Various U.S. and foreign governments, consumer agencies, self-regulatory bodies, and public advocacy groups have called for or implemented new regulation directly impacting the digital advertising industry.

A number of states, including California, have enacted comprehensive consumer privacy laws regulating the collection and use of data to target advertisements, and we expect to see more state laws and potentially federal regulation in the future. Such legislation or regulation could affect the costs of doing business online and may adversely affect the demand for or the effectiveness and value of our solution.

These state laws require all businesses that engage in certain advertising uses of consumer personal data to offer and honor an opt-out of such activities, including, in some states, through universal browser or device-based preference signals such as GPC. Some state laws may also restrict use of sensitive information, including precise location information, for advertising purposes. The implementation of these state laws and any corresponding regulations will cause us to incur additional compliance costs and may impose additional restrictions on us and on our industry partners.

Separate from these comprehensive state consumer privacy laws, lawmakers continue to focus their efforts on data collection, processing, and disclosures by companies that do not have direct relationships with the consumers whose personal data they process. Several states, including California, Oregon, and Texas, have recently enacted or updated laws restricting the activities of "data brokers." Notably, California's Delete Act, dramatically increases obligations and potential penalties relative to the state’s preexisting data broker statute. Beyond additional transparency requirements, beginning in August 2026, companies registered as data brokers in California (including Magnite), must honor universal deletion requests consumers make of all data brokers via the state's Delete Request and Opt-out Platform mechanism. These obligations may reduce the data available to Magnite, require us to develop complex and expensive compliance tools and procedures, and may result in reductions in revenue.

In the European Economic Area ("EEA") and the United Kingdom ("UK"), the General Data Protection Regulation, Regulation (EU) 2016/679 ("GDPR") and UK General Data Protection Regulation ("UK GDPR") respectively treat much of the end-user information that is critical to programmatic digital advertising as "personal data", subject to significant conditions and restrictions on its collection, use, transfer and disclosure. The GDPR and UK GDPR also set out substantial potential liabilities for certain data protection violations and create a compliance burden for us in the course of delivering our solution in Europe.

Further, many governments are restricting the transmission or storage of information about individuals beyond their national borders. Such restrictions could, depending upon their scope, limit our ability to utilize technology infrastructure consolidation, redundancy, and load-balancing techniques, resulting in increased infrastructure costs, decreased operational efficiencies and performance, and increased risk of system failure.

Moreover, we have from time-to-time become subject to putative class actions or other litigation, including claims based on developing or unsettled interpretations of privacy, data use, or consumer protection laws, which regardless of their ultimate merit may require significant resources to address, divert management attention, and result in reputational harm or adverse outcomes.

These laws and regulations are continually evolving, not always clear, and not always consistent across the jurisdictions in which we do business. Any failure to protect, and comply with applicable laws and regulations or industry standards applicable to, personal data or other data relating to consumers could result in enforcement action 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.

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The GDPR and UK GDPR impose strict requirements for transferring personal data from the European Economic Area and United Kingdom to the United States and other countries, and regulatory guidance and case law on international transfers is continually evolving; this increases uncertainty and may require us to change our EEA and UK data practices and/or change our technology solution or business model, which may in turn adversely affect demand for our solution.

The GDPR and UK GDPR generally prohibit the transfer of personal data of EEA and UK subjects outside of the European Economic Area and the UK to countries whose laws do not ensure an adequate level of protection, unless a lawful data transfer solution has been implemented. On July 16, 2020, in a case known as "Schrems II," the Court of Justice of the European Union ("CJEU") ruled on the validity of two of the primary data transfer solutions. The first method, EU-U.S. Privacy Shield operated by the U.S. Department of Commerce, was declared invalid as a legal mechanism to transfer data from the EEA and UK to the U.S. A successor agreement, the Data Privacy Framework (“DPF”), is now in place, but numerous lawsuits against the DPF have already been filed, and it is uncertain whether DPF will stand up to judicial scrutiny by the CJEU or, like its predecessor agreement, be declared invalid.

The GDPR imposes requirements for end user consent or opt-out that may cause us to incur additional or unexpected costs, subject us to enforcement actions for compliance failures, or cause us to change our service or business model, which may have a material adverse effect on our business.

The European Union Privacy and Electronic Communications Directive (Directive 2002/58/EC), commonly referred to as the "ePrivacy Directive," and the GDPR require consent or another legal basis in order to process personal data for purposes of behavioral advertising, and there is currently significant risk and uncertainty regarding the standard for obtaining valid consent. Current regulatory developments indicate stricter interpretation of the ePrivacy Directive, meaning that data processing without consent will continue to decrease.

End-user consent is difficult for ad tech intermediaries like us to obtain because we do not have direct relationships with such end users, so we have historically relied upon sellers to obtain consent for use of our technology. To the extent any seller does not adequately satisfy its consent obligations for our technology, we may face regulatory risk. Further, emerging regulatory guidance in the EU has challenged this method of obtaining consent.

Legal standards and regulatory guidance will continue to evolve. National regulators in the UK and EU are evolving their guidance on the use of advertising technologies and compliance with the GDPR and ePrivacy Directive. This guidance may be burdensome or inconsistent across countries, and present challenges to the way we operate.

As a result of all of the factors set forth above, our or our clients’ ability to serve target advertisements may become significantly impaired or complicated in certain jurisdictions.

We are subject to regulation with respect to political advertising, which lacks clarity and uniformity.

We are subject to regulation with respect to political advertising activities, which are governed by various federal and state laws in the U.S., and national and provincial laws worldwide, including the new Transparency and Targeting of Political Advertising in the EU, imposing strict prohibitions on the use of personal data for political advertising. Online political advertising laws are rapidly evolving and in certain jurisdictions we have compliance requirements with respect to political ads delivered on our platform. In some jurisdictions we may determine not to serve political advertisements due to uncertainty around these requirements and potential burdens of compliance. In addition, our sellers may impose restrictions on receiving political advertising. The lack of uniformity and increasing compliance requirements around political advertising may adversely impact the amount of political advertising spent through our platform, increase our operating and compliance costs, and subject us to potential liability from regulatory agencies.

Issues related to industry self-regulation could harm our brand, reputation, and our business.

In addition to compliance with government regulations, we voluntarily participate in trade associations and industry self-regulatory groups that promulgate best practices or codes of conduct addressing privacy and the provision of digital advertising. If we encounter difficulties abiding by these principles, we may be subject to negative publicity, as well as investigation and litigation by governmental authorities, self-regulatory bodies or other accountability groups, buyers, sellers, or other private parties. Any such action against us could be costly and time consuming, require us to change our business practices, divert management's attention and our resources, and be damaging to our reputation and our business.

Our business is subject to evolving corporate governance and public disclosure regulations and expectations, including with respect to sustainability matters that could expose us to numerous risks.

Regulators, customers, investors, employees and other stakeholders are increasingly focusing on sustainability matters and related disclosures. These changing rules, regulations and stakeholder expectations have resulted in, and are likely to continue to result in, increased general and administrative expenses and increased management time and attention spent complying with or meeting such regulations and expectations. Emerging regulations in various jurisdictions, including mandatory disclosure requirements and carbon reporting obligations, as well as related uncertainty from modifications to or

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reversals of such regulations or inconsistency between regulatory requirements in different jurisdictions, may further increase the complexity and cost of compliance.

We may also communicate certain initiatives and goals regarding sustainability matters in our SEC filings or in other public disclosures. While we aim to achieve these goals, we could face scrutiny from certain stakeholders for the scope, ambition, or execution of such initiatives, and stakeholders and regulators have increasingly expressed or pursued opposing views, legislation, and investment expectations with respect to sustainability initiatives, including the enactment or proposal of "anti-ESG" legislation or policies. Revisions to or failure to maintain our goals, delays in achieving progress, or perceived shortcomings in our initiatives or goals could harm our reputation, erode stakeholder trust, and adversely impact our relationships with customers, investors, or employees.

Furthermore, if our sustainability-related data, processes, and reporting are incomplete, inaccurate, or fail to meet regulatory standards, we could be subject to penalties, regulatory scrutiny or enforcement actions, or legal actions. Misalignment between our sustainability practices and stakeholder expectations, or the inability to satisfy all stakeholders in light of their varied and sometimes conflicting views regarding environmental and social matters, could also impact our ability to attract and retain investors, secure partnerships, or compete effectively in the marketplace and could expose us to operational disruptions, increased costs, and reputational damage, adversely affecting our business, financial performance, and growth prospects.

Our litigation with Google LLC presents potential risks that could adversely affect our business, results of operations and financial condition.

On September 16, 2025, we filed a lawsuit in the U.S. District Court for the Eastern District of Virginia against Google LLC ("Google") seeking financial damages and other remedies (the "Google Action") in light of the U.S. District Court’s ruling that Google had engaged in unlawful anticompetitive practices with respect to certain ad tech markets. Google is a significant participant in the digital advertising ecosystem and both a major partner and competitor to Magnite and a significant portion of our revenue is generated through our relationship with Google. The Google Action is in its early stages, and the outcome and timing of the Google Action is uncertain and difficult to predict. The Google Action presents several risks to our business, including the potential for retaliatory actions by Google. Any such actions could disrupt our ability to serve our customers and partners, reduce our revenue, and harm our relationships with publishers and advertisers. The Google Action may be costly, protracted, and divert management's attention and resources from our business operations. Any damages awarded may not be commensurate with our expectations, and we may not receive any monetary damages at all. The existence of the Google Action and any potential retaliatory measures could also negatively affect our reputation and our ability to compete, potentially causing our business, financial condition, and results of operations to be materially and adversely affected.

Risks Related to Our Operations

Real or perceived errors or failures in the operation of our solution could damage our reputation and impair our sales.

We must operate our technology infrastructure without interruption to support the needs of sellers and buyers. Because our software is complex, undetected errors and failures may occur, especially when new versions or updates are made to our software or network infrastructure, changes are made to sellers' or buyers' software interfacing with our solution, or as we further integrate acquired technologies. Any unknown errors or bugs in our software, faulty algorithms, technical or infrastructure problems, or updates to our systems could lead to an inability to effect transactions or process data to place advertisements or price inventory effectively, cause the inadvertent disclosure of proprietary data, or cause advertisements to display improperly or be placed in proximity to inappropriate content. Such errors or failures could also result in negative publicity, disclosure of confidential information, damage to our reputation, loss of or delay in market acceptance of our solution, increased costs or loss of revenue, loss of competitive position, or claims by advertisers for losses sustained by them. We may make errors in the measurement of transactions conducted through our solution, causing discrepancies with the measurements of buyers and sellers, which can lead to a lack of confidence in us and require us to reduce our fees or provide refunds to buyers and sellers. Alleviating problems resulting from errors in our software could require significant expenditures of capital and other resources and could cause interruptions, delays, or the cessation of our business.

Various risks could interrupt access to our network infrastructure or data, exposing us to significant costs and other liabilities.

MGNI US Equity

MGNI · 10-K · period ended 2025-12-31

Item 1. Business

Item 1A. Risk Factors

MGNI US Equity☆

MGNI · 10-K · period ended 2025-12-31

Item 1. Business

Item 1A. Risk Factors

MGNI US Equity