Duolingo, Inc. (DUOL) Business

Item 1. Business

Our mission is to develop the best education in the world and make it universally available.

Although education can open the door to economic opportunity, it is also among the principal sources of inequality: the privileged can get the best education in the world, while those with fewer resources, especially in developing countries, may not be able to get even basic schooling. That is why we started Duolingo. We believe that everyone, regardless of how wealthy they are, should have access to high quality education. And today, the technology necessary to enable this is in the hands of billions of people, in the form of a smartphone. At Duolingo, we build products native to the smartphone—bite-sized, on-demand and engaging—to make learning accessible and effective, opening doors for everyone alike.

Who We Are

Duolingo is a technology company founded by two engineers, Luis von Ahn and Severin Hacker. Luis and Severin met at Carnegie Mellon University, where Luis was a professor in the Computer Science Department and Severin was his Ph.D. student. Luis, a MacArthur Fellow, grew up in Guatemala and witnessed firsthand the tremendous impact that access to high quality education can have on people’s lives. Luis and Severin bonded over the dream of building an intelligent learning system informed by massive amounts of user engagement data that could deliver superior learning outcomes.

Our team, which as of December 31, 2025, consisted of more than 900 passionate employees, including more than 430 engineers, aims to build the most sophisticated education platform in the world. We believe that by combining modern technology, the very best talent, and a mission-driven approach, we can create better learning experiences and meaningful improvements in efficacy. Our products are powered by sophisticated data analytics and AI and delivered with world-class art, animation, and design to make it easier for learners to stay motivated, master new material, and achieve their learning goals.

Our Business

Our flagship app has organically become the world’s most popular way to learn languages and the top-grossing Education app in the app stores. For many, Duolingo has become synonymous with language learning: for example, on Google, people search for the term “Duolingo” much more often than “learn Spanish.” We are particularly proud that our learners come from the entire socioeconomic spectrum, ranging from billionaires and celebrities to recently resettled refugees, a rare instance in which more money does not imply better access to a high quality educational platform.

We started with a focus on teaching languages because of the profound impact learning a new language can have on people’s lives, as well as the large market opportunity. According to HolonIQ in January 2024, consumer spend on both online and offline language learning is expected to reach about $123 billion by 2027. Driving much of the demand for language learning is the reality that English can unlock tremendous economic opportunity. And the power of language learning is not limited to economic advancement. Learning another language can unlock new experiences and deepen human connections, ranging from navigating a first trip to another country to communicating with family members of an older generation.

As of December 31, 2025, Duolingo offers over 250 total language courses to more than 130 million monthly active users. To provide perspective on our reach, in the United States (“U.S”), the number of people learning a language using Duolingo is greater than the number of K-12 students taking a foreign language class in school, and there are more people learning certain languages on Duolingo, like Irish and Hawaiian, than there are native speakers of those languages worldwide.

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While languages remain our core focus, we began expanding into additional subjects aligned with our mission to develop the best education in the world and make it universally available. We now offer courses in Math and Music, and recently launched Chess, which is growing rapidly as learners embrace these new subjects on the Duolingo platform.

Duolingo is the learning product built for the mobile generation: bite-sized, on-demand, and fun. We believe that the hardest part of learning something new is staying motivated, so we build gamification features into our platform to motivate our learners, and we run thousands of A/B tests to optimize each feature for maximum engagement. Our obsession with user experience has yielded affinity and loyalty in our learners, which in turn has helped us cultivate millions of brand advocates who tell their friends and families about our products. Our brand has become part of pop culture, appearing in internet memes and in sketches on late night comedy shows. All of this has allowed us to grow our business organically, primarily driven by word-of-mouth and brand buzz, and supplemented by selective and targeted paid user acquisition.

Our millions of learners complete nearly 2 billion exercises every day, creating what we believe to be the world's largest learning dataset. This data powers the high volume A/B testing and AI-driven systems that we use to continually improve how well we teach. According to an internal study, learners who completed five sections of Duolingo achieved proficiency comparable to five university semesters of language education. Independent studies corroborate this finding: Duolingo learners’ speaking skills were found to match those of university students, and users learning English on Duolingo outperformed students in traditional classroom settings on standardized language proficiency tests. Studies also found that our instructional quality continued to improve, and new learning features like Roleplay, Explain My Answer, DuoRadio, and Video Call contributed to increased learner confidence and measurable gains in listening and speaking skills.

We believe rapid advances in Artificial Intelligence (“AI”) will fundamentally change the way people learn. As a technology company and global education platform, we believe we are well positioned to play a leading role in this innovation. AI plays an increasingly important role in how we provide effective learning experiences and generate content at scale. For example, Roleplay, Explain My Answer, and Video Call are all AI-powered learning features. While the use of AI enhances the learning experience and supports product innovation at scale, it also requires increased investment in computing infrastructure and related costs, which we actively manage as we continue to expand these capabilities.

Our ability to operate at scale supports our freemium business model, which means allowing users to access our content for free and charging a subscription for additional features, is core to our success because it enables significant user scale. We intentionally do not put our learning content behind a paywall. Anyone can download the Duolingo App, use it for as long as they like, and complete as many of our courses as they choose, all without paying anything. Learners who use Duolingo for free see an ad at the end of each lesson, whereas learners who purchase one of our paid subscriptions enjoy an ad-free experience and access to additional features. As of December 31, 2025, approximately 9% of our monthly active users were paid subscribers. Our paid subscriber penetration has increased significantly since we launched our paid subscription in 2017 and, combined with our user growth, has driven strong revenue growth each year since. We have a strong future roadmap of feature improvements and optimizations, and believe our subscriber base has strong growth ahead.

Our growth and competitive differentiation have been driven by two mutually-reinforcing flywheels: our learning flywheel and our investment flywheel.

•Learning flywheel: The greater the scale of our learner base, the more we can use insights from data to improve both engagement and efficacy. We do this through continual experimentation.

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The more engaging our products are, and the more effectively we teach, the more our learners tell their friends about Duolingo and the more we continue to grow our learner base.

•Investment flywheel: The scale of our learner base and word-of-mouth growth allows us to focus our capital investments on product innovation and data analytics, rather than relying primarily on brand or performance marketing. The more learners use Duolingo and convert into paid subscribers, the more we are able to invest in creating an even more delightful, engaging and effective learning experience. In turn, this increases our popularity and user scale, as well as the effectiveness of our data analytics and AI systems, further widening our moat.

In 2016, we launched the Duolingo English Test, an online, on-demand assessment of English proficiency. Every year, millions of people around the world seek to demonstrate English proficiency for a variety of reasons, including university admissions, work visas, and job applications. We developed the Duolingo English Test because language assessment has lacked innovation, with the most popular English proficiency tests still administered in physical testing centers and usually costing hundreds of dollars per test. By offering a more accessible, online option that is both rigorous and accurate, we provide greater opportunities for aspiring students and professionals dependent on the successful completion of these high stakes assessments. As of December 31, 2025, over 6,100 education programs around the world accept the Duolingo English Test results as proof of English proficiency for international student admissions, with over 5,300 of those being higher education programs. These include 24 of the top 25 undergraduate programs in the U.S. ranked by international enrollment, as well as all of the Ivy League, MIT, and Stanford.

We believe that there is a significant opportunity to diversify the scope of our platform beyond language learning to a variety of subjects, using the same product-focused, mobile-first, gamified approach to education. In 2022 we launched a math course that motivates both children and adults to sharpen their mental math skills and continue to develop our standards-aligned curriculum. In 2023, we launched a music course that's designed to teach music literacy, including how to read music notes and play songs. In 2025, we launched a new chess course to teach one of the world’s most popular games. These courses have all been integrated into the Duolingo App. We believe new products will leverage our scalable technology platform and benefit from our core competencies in product development, gamification and use of advanced data-driven analytics to deliver quantifiable efficacy. We believe that expanding the scope of our platform to additional learning subjects will further expand our addressable market.

The Duolingo Learning Experience

The Duolingo learning experience sits at the rare intersection of fun and self-improvement. We believe that learners love Duolingo because:

•It's fun. Duolingo feels more like a mobile game than an education product. Our bite-sized lessons and gamification features motivate learners to come back each day to continue learning. As of December 31, 2025, there were about 43 million daily active users with a 7-day streak or longer, and about 15 million daily active users with a 365-day streak or longer. A streak indicates the number of days in a row a lesson is completed.

•It's effective. Learners stick with Duolingo at first because it’s fun, and then over time also because they find that it works. Our expert-designed courses help learners build robust skills, and our AI technologies power personalization leading to superior learning outcomes. For more information, please visit https://www.duolingo.com/efficacy.

•It's free. Every course on Duolingo is free to access. Learners can spend as much time learning as they want and complete any and every course without paying. This lowers barriers to start learning and to keep learning.

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In a world where people are increasingly engaged in immersive, bite-sized, mobile-first experiences, we provide an experience that also results in learning valuable skills.

The Duolingo Method

The Duolingo Method, which is our approach to teaching, comprises five principles that guide how we create new learning content, design engaging lessons, and build courses that are as effective as they are fun. Our learning, product, and design teams have developed this approach by combining research on teaching and learning, our experiences as teachers, and the results of more than a decade studying how our self-guided learners learn best.

•Learn by doing. Each Duolingo lesson is designed with interactive exercises that put learners at the center of their own learning and allows them to immediately use what they are learning. This type of learning-by-doing engages the brain and leverages its natural ability to pick up on patterns present in the surroundings, often without conscious realization—it's a fundamental way our minds operate. Duolingo lessons draw learners' attention to important patterns (such as verb conjugations or word order rules for language, or fraction creation for math), helping to solidify these concepts over time so that learners are ready to use what they learn in the real world.

•Learn in a personalized way. Tailored lessons enable learners to progress at their own pace, adapting the material to their individual strengths and weaknesses. Our AI models track their learning journey, adjusting the order and difficulty of the exercises they see so that they are always seeing a balance of familiar and more challenging content. Research shows that giving learners just the right level of difficulty—right at the edge of what they know—pushes them toward developing new skills and leads to higher engagement. We also use algorithms to create unique practice sessions that help learners strengthen the skills where they could use the most help.

•Focus on what matters. Our curricula are informed by national and international standards to provide comprehensive coverage of what’s considered important for each field of knowledge. We then complement these documented standards with our learning experts' experience to develop well-rounded courses that give learners a strong foundation and all the tools to take their learning out into the world.

•Stay motivated. The entire Duolingo experience is designed to support learners in maintaining their study habits over the long term. With bite-sized lessons that require just a few minutes to complete, fitting study into a busy schedule becomes effortless. The gamification elements within each course are designed to encourage a return to learning: completing lessons awards points and extends streaks, while offering numerous chances for collaboration and friendly competition with other learners. These features not only help learners feel a sense of accomplishment and stay driven to achieve their goals, but research also indicates they are more engaged and learn more effectively as a result.

•Feel the delight. We know people learn better when they have joyful experiences, so we build light-hearted learning into every course and lesson. Our cheerful characters, with their own personalities and backstories, show up throughout the courses and make the learning experience more interesting and meaningful. Learners also find encouraging words and supportive messages from Duo the owl. And this fun spirit is in the lessons, too, because funny content sticks and makes learning more memorable.

Our Technology Platform

Technology is at the core of everything we do. We utilize the latest in AI, machine learning and data analytics, along with a relentless focus on A/B testing, to fuel our differentiated learning experience.

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Highlights of our technology platform include:

•Large data moat. With nearly 2 billion exercises completed every day on our platform, we believe we have built the world's largest collection of language-learning data. We leverage this data by developing novel AI models at the intersection of machine learning, natural language processing, and cognitive science, which enable personalized instruction and power new product features that drive both engagement and efficacy.

•Robust testing framework. The foundation of our product strategy is our relentless focus on improving learner engagement through A/B testing, and we run hundreds of A/B tests on new product features each quarter. Experiments can be as simple as changing the text or color of a button, or as complex as adding a major new feature like Video Call. The velocity of our A/B testing capabilities is a core competency that we believe allows us to optimize the Duolingo learning experience at a rapid pace and leads to compounding growth of core business metrics like DAUs and paid subscribers.

•Advanced AI, machine learning, and data analytics capabilities. Our machine learning capabilities allow us to leverage our data to optimize the learning experience. One example of this is our machine learning tools that evaluate every learner’s answer to every exercise every day and learn to predict the probability that any learner will answer any given exercise correctly. We use these tools to adaptively construct lessons where each exercise is “just right” in terms of difficulty for each learner. And our expertise in AI and machine learning also allow us to effectively and efficiently integrate external AI models to improve our products. For example, we are able to generate high quality course content at materially faster speeds due to leveraging AI, and AI powers numerous new learning features contributing to gains in learner outcomes.

•Shared infrastructure. Products across our platform, like our flagship Duolingo App (including our Math, Music, and Chess courses), and the Duolingo English Test, share a singular technology infrastructure, which allows us to leverage operational efficiencies in implementing new features for each. With our shared infrastructure, we are able to innovate at a higher velocity.

•Strict data protection and privacy standards. We are committed to abiding by the strictest privacy standards and do not sell personal data to outside parties.

Our Solutions

The Duolingo App

The Duolingo App is the world’s most popular way to learn languages. Accessible for free, as of December 31, 2025 it offers over 250 total language courses to more than 130 million monthly active users. It is also the top-grossing app globally in the Education category on both Google Play and the Apple App Store. Duolingo can also be accessed by desktop computers via a web browser at https://duolingo.com. Math, Music, and Chess courses are also integrated into the Duolingo App.

Super Duolingo

While all of Duolingo’s course content can be accessed for free, our subscription offering, Super Duolingo, offers learners additional features to enhance their learning experience. In 2021, we launched a family plan, which includes up to six subscribers under one annual plan.

Duolingo Max

Duolingo Max is a premium subscription tier launched in 2023 and offered to a portion of our user base and priced higher than Super Duolingo. It gives learners access to the existing features of Super Duolingo in addition to incremental features and exercises powered by AI technology.

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Duolingo English Test: AI-Driven Language Assessment

Launched in 2016, the Duolingo English Test is an online, on-demand, high-stakes (e.g., used for university admissions) English proficiency assessment. To take the test, an individual must have access to both (i) a computer equipped with a webcam and (ii) a smartphone, as well as a reliable internet connection. The test can be taken from anywhere, at any time. The test is “computer adaptive”, meaning it gets harder or easier depending on the performance of the test taker, and can be completed in less than an hour.

Other Initiatives

Duolingo also offers Duolingo for Schools and Duolingo ABC. Duolingo for Schools is a web-based tool that aims to make it easier for teachers to use the Duolingo platform in a structured learning environment, like a classroom. Duolingo ABC is an app that teaches young children early literacy skills.

People and Culture

Attracting and retaining amazing talent is key to our success. We believe that being located outside of Silicon Valley has helped us cultivate a unique company culture. Fundamental to Duolingo's culture is our mission orientation. Our mission tends to attract a certain kind of person. Our employees have a very strong sense of social responsibility and are interested in solving hard problems for the benefit of humanity. Over time, we have developed a set of principles that define what we value as a company and guide how we make our decisions and spend our time.

Our Principles

•Take the Long View. If it helps in the short-term but hurts Duolingo in the long-term, it’s not right.

•Raise the Bar. To change how the world learns, we must do world-class work.

•Ship It. For a good idea to become reality, we need to move with a sense of urgency. So Go, Go, Go!

•Show Don’t Tell. We use clear, concise communication that is grounded in data and real impact.

•Make It Fun. We bring a sense of humor, joy, and imagination to everything we do.

As a result of our mission, our culture, and the challenges we work on every day, we believe we have had great success in attracting the best talent. We have a very selective recruitment process: we recruit interns and new graduates from the top computer science, design, and business programs in the country. We also recruit experienced professionals from top technology companies—and many of them relocate from other major tech hubs to Pittsburgh.

We are proud to say that Duolingo was founded by two immigrants and that our employees represent a wide range of countries and backgrounds, representing the diversity of our global learner community. We believe an environment of inclusion and belonging, where individuals can excel regardless of their background, is important to our long-term performance and value. We also recognize the importance of pursuing such efforts in a legally sound manner. It is our policy to not make employment (including hiring, promotion, or compensation) decisions on the basis of any legally protected characteristic, and to consider our efforts through a legal compliance lens.

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Sales & Marketing

For almost a decade, Duolingo’s learner community has grown organically through word-of-mouth virality. In recent years, we have made investments in marketing to supplement our organic model and amplify the voices of our existing users. Key elements of our sales and marketing strategy include:

•Brand building. Our brand marketing increases awareness of Duolingo through online and offline campaigns that drive press, social sharing, and more word-of-mouth virality. Investments in our brand enable us to drive long-term growth by attracting new learners to our platform and keeping existing learners engaged. We leverage our iconic brand on social media platforms to drive organic new user growth and engagement with entertaining content, instead of promotional content, that takes advantage of viral trends and Duolingo memes created by our community.

•Owned media marketing. Our owned media marketing engages our learner community, creating millions of brand advocates who drive word-of-mouth virality by sharing their love of Duolingo within their networks. We send our learners personalized emails and push notifications that provide progress reports, lesson reminders, and sometimes a simple message of positivity to encourage them to remain engaged.

•Paid acquisition. We complement and accelerate our organic user growth with strategic and targeted paid user acquisition. Our performance marketing strategy is focused on targeting high quality user segments around the world that are more likely to retain well as users and/or subscribe.

•Geographic expansion. In markets where our organic awareness is relatively low and the opportunity for growth is strong, we hire experienced local marketing managers and engage in localized social media and influencer-led campaigns, app store optimization, and paid advertising to generate interest in our products and drive new learner growth.

Industry Trends

We believe the following market trends will contribute to the continued success of our platform:

•AI will increasingly shape online learning. Rapid advances in AI, particularly large language models, will change how people use technology to learn. We believe that this trend will continue to accelerate, and that it will offer an almost unimaginable set of opportunities for companies at the nexus of technology and education to teach at scale.

•Online learners seek engaging, mobile-first experiences. Consumers are increasingly accustomed to the highly engaging design of social media apps and mobile games. We believe that consumers turning to online learning will not only prefer the convenience and control that mobile apps provide, but also expect experiences to be highly engaging.

Competition

We believe that our relentless focus on building an engaging and effective learning product, powered by our freemium model, has led to a leading market position, as measured by downloads, active users, and brand awareness. However, learners have a variety of options when choosing to learn a language. We compete for learners’ time, attention, and share of wallet not only with other online and app-based language learning platforms but also with offline forms of language learning. Because of the extensibility of the Duolingo platform beyond language learning, we also compete with language learning assessment providers, literacy platforms, as well as math, music, and chess learning products.

We believe that our ability to compete successfully depends primarily on the following factors:

•Continued growth in internet access and mobile adoption around the world;

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•Our ability to continue to increase our learner base through organic, word-of-mouth and the ongoing engagement provided by our free user experience;

•Our ability to maintain the value and reputation of our brand;

•Our ability to obtain, protect and maintain our intellectual property rights and proprietary technology;

•The scale, growth and engagement of our learners relative to those of our competitors;

•Our ability to introduce new, and improve on existing, features and products in response to competition, learner preferences, and market and industry trends; and

•Our ability to continue developing new monetization features and improving on existing features.

Intellectual Property

We own several trademarks that have been registered, or for which registration applications are pending, in the U.S. as well as in a number of foreign jurisdictions. These trademarks include, among others, the word marks “Duolingo” and Duolingo in Chinese, and certain logos used in connection with our business, including our mascot Duo. The registrations of these trademarks are effective for varying periods of time and may be renewed periodically provided we comply with all applicable renewal requirements, including, where necessary, the continued use of the trademarks in the applicable jurisdictions in connection with certain goods and services. We may consider pursuing trademark registrations for additional marks and for additional jurisdictions if and to the extent we believe such registrations would be beneficial to our business and cost-effective.

We have registered several domain names, including www.duolingo.com, and we own several copyrights (both registered and unregistered) covering logos and characters used in our business, including Duo. We also enter into, and rely on, confidentiality and proprietary rights agreements with our employees, consultants, contractors and business partners to protect our trade secrets, proprietary technology and other confidential information. We further protect the use of our proprietary technology and intellectual property through provisions in both our user terms of use on our website and in our agreements with service providers.

In addition to the described trademark and domain name protection, Duolingo has filed two patent applications directed to proprietary techniques we developed for generating language proficiency test questions and evaluating language proficiency as part of an on-going program to identify and protect innovations developed by the Company. We expect that this program will continue and increase in size going forward. For information regarding risks related to our intellectual property, please see “Risk Factors—Risks Related to Our Intellectual Property.”

Government Regulation

We are subject to many U.S. federal and state and foreign laws and regulations, including those related to privacy, rights of publicity, data protection, payment processing, disability rights, digital accessibility standards, content regulation, intellectual property, health and safety, competition, protection of minors, consumer protection, and taxation. These laws and regulations are constantly evolving and may be interpreted, applied, created, or amended in a manner that could harm our business. In addition, the application and interpretation of these laws and regulations often are uncertain, particularly in new and rapidly evolving industries.

We collect and use personal information to create online accounts, process e-commerce transactions, provide customer service, support, and for other purposes. The regulatory framework for data protection,

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privacy and information security is evolving rapidly. For example, the U.S. Federal Trade Commission (“FTC”) and many state attorneys general are applying federal and state consumer protection laws to require that the online collection, use and dissemination of data, the presentation of website or other electronic content, and broad commercial and digital marketing activities, comply with certain standards for notice, choice, security and access, among other things. Courts may also adopt these developing standards. A number of states, including but not limited to California and Virginia, have enacted laws or are considering the enactment of laws governing the personal information received from consumers, and imposing new requirements around the collection, use, sharing, and handling of data collected from or about consumers or their devices. In many cases, the specific limitations imposed by these standards are subject to interpretation by courts and other governmental authorities. In addition, federal and state regulators have interpreted various rules and regulations as requiring companies like ours to implement reasonable data security controls and measures.

We are also subject to laws that govern specific types of data and/or specific types of marketing or other consumer engagement activities. For example, the Children’s Online Privacy Protection Act (“COPPA”) applies to operators of commercial websites and online services directed to U.S. children under the age of 13 that collect personal information from children and to operators of general audience sites that have actual knowledge that they are collecting information from U.S. children under the age of 13. Our Duolingo App is aimed at a general audience and we employ an age-gating procedure whereby anyone from the U.S. identifying themselves as being under the age of 13 during the registration process receives an ad-free version of the service, with special enrollment procedures and restricted information practices. We also apply age-gating for non-US users of the Duolingo App according to foreign laws. The Duolingo English Test service requires parental consent for users under the age of 13. The Duolingo ABC app is aimed at users under the age of 13 but does not collect personal information directly from the user beyond that required to use the app. Other laws such as the Restore Online Shoppers’ Confidence Act (“ROSCA”) and analogous state laws require certain and consent mechanisms, among other things, in relation to recurring payments and subscription based products or services. These rules are enforced by federal and state regulators and can subject companies to significant penalties, fines and injunctive relief. In addition, federal and state agencies regularly investigate and bring enforcement actions under general unfair or deceptive acts or practices laws (referred to as “UDAP” statutes) in relation to a broad array of sales, marketing and advertising activities.

We also have many subscribers who access and pay for our services from outside the U.S. Foreign data protection, e-commerce, privacy, consumer protection, content regulation and other laws and regulations are often more restrictive or burdensome than those in the U.S., and those governments may attempt to apply such laws extraterritorially or through treaties or other arrangements with U.S. governmental entities. For example, in the European Economic Area (“EEA”) we are subject to the General Data Protection Regulation 2016/679 (“GDPR”) and in the United Kingdom (“U.K.”) we are subject to the U.K. GDPR. The GDPR and the U.K. GDPR impose strict data protection compliance requirements including: providing detailed disclosures about how personal data is collected and processed (in a concise, intelligible and easily-accessible form); demonstrating that an appropriate legal basis is in place or otherwise exists to justify data processing activities; compliance with rights for data subjects in regard to their personal data (including the right to be “forgotten” and the right to data portability), notifying data protection regulators or supervisory authorities (and in certain cases, affected individuals) of significant data breaches; confirming that appropriate safeguards are in place where personal data is transferred out of the EEA and the U.K.; limiting retention of personal data; maintaining a record of processing activities; and complying with the principle of accountability and the obligation to demonstrate compliance through policies, procedures, training and audit.

Brazil also enacted the Lei Geral de Proteção de Dados (the “Brazilian General Data Protection Law”), which became effective in August 2020 and imposes requirements largely similar to GDPR on products

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and services offered to users in Brazil. We may also be subject in China to the Cybersecurity Law that went into effect in June 2017 and a revision of the Personal Information Security Specification that went into effect in October 2020, which have uncertain but broad application and impose a number of new privacy and data security obligations. In the summer of 2021, China passed the Data Security Law of the P.R.C., which came into effect on September 1, 2021. China also passed the Personal Information Protection Law of the P.R.C. (“PIPL”), which came into effect on November 1, 2021. The PIPL resembles GDPR in many aspects but will create new and challenging obligations for companies doing business in China. Under these new regulations, if an entity operating in China violates the law, regulators may order it to take corrective actions, issue warnings, confiscate illegal income, suspend services, revoke operating permits or business licenses, or issue a fine. The fine can be up to ¥50 million or 5 percent of an organization’s annual revenue for the prior financial year. A broad range of other countries continue to explore either new privacy and data security laws or changes to existing laws.

Available Information

Our website address is www.duolingo.com. The contents of, or information accessible through, our website are not part of this Annual Report on Form 10-K. The reference to our website address does not constitute incorporation by reference of the information contained on or available through our website, and you should not consider such information to be a part of this Annual Report on Form 10-K. We make our filings with the SEC, including our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, proxy statements, reports under Section 16 of the Exchange Act and all amendments to those reports, available free of charge on our website as soon as reasonably practicable after we file such reports with, or furnish such reports to, the SEC.