RISK FACTORS

         Investment in our ADSs involves significant risks. You should carefully consider the risks described below before you decide to buy our ADSs. If any of the possible adverse events discussed below actually occurs, our business, prospects, financial condition, and results of operations could be materially and adversely affected, the trading price of our ADSs could decline, and you could lose all or part of your investment.

Risks Related to Our Business

The online search industry in China is extremely competitive, and if we are unable to compete successfully, it will be difficult for us to maintain or increase our revenues and profitability.

        We operate our business in an extremely competitive industry. We face intense competition in every aspect of our business, including competition for users, advertisers, technology, and talent. We face competition for our search and search-related services in China primarily from Baidu Inc., or Baidu, and ShenMa, operated by UCWeb Inc., or UCWeb, which is a subsidiary of Alibaba Group Holding Limited, or Alibaba. Both Baidu and Alibaba have considerably greater financial and technical resources available to them than we do. We also face competition for both users and advertisers from websites and mobile applications that provide specialized search services in China, including travel services and information platforms such as Ctrip and Qunar; group-buy platforms such as Meituan Dianping; online classified advertisement platforms such as 58.com; and newsfeeds such as Toutiao. We compete for advertisers not only with Internet companies, but also with other types of advertising media such as newspapers and magazines, billboards and bus advertisements, television, and radio. It is also possible that multinational businesses with considerably greater financial and other resources than ours could expand their offerings in China, making it harder for us to gain market share.

        Our existing and potential competitors compete with us for users and advertisers on the basis of the quality and quantity of search results; the features, availability, and ease of use of products and services; and the number and quality of advertising distribution channels. They also compete with us for talent with technological expertise, which is critical to the sustained development of our products and services. If we are unable to differentiate ourselves from our competitors in each of these areas, we may not be able to maintain or increase our user and advertiser base, which would have an adverse impact on our business, results of operations, and growth potential. In addition, we may have difficulty in successfully promoting and differentiating our new products, services, and features as a result of the market power of our competitors.

We must expand our user base to grow our business, and we must continually innovate and adapt our business in an evolving online search industry in order to do so. If we fail to continue to innovate and introduce products and services to enhance user experience, we may not be able to generate sufficient user traffic to remain competitive.

        The Internet industry in general and the online search industry in particular have been undergoing rapid changes in technology and in user preferences. Our future success in expanding our user base will depend on our ability to respond to, as well as anticipate and apply, rapidly evolving technologies. We must adapt our existing products and services and develop new products and product areas that will meet the evolving demands of users, deliver attractive experiences for our users that enhance user engagement, and cause our users to return to our services and increase the frequency of their searches on our platforms. Our development and introduction of new products, features, and services are subject to additional risks and uncertainties. Unexpected technical, operational, distribution, or other problems could delay or prevent the development and introduction of one or more of our currently planned and any future new products and services. There are constant innovations in the market regarding search services, search and search-related advertising, and providing information to users. If we are unable to predict user preferences or industry changes, or if we are unable to modify our products and services

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on a timely basis, we may lose users. Our operating results will also suffer if our innovations are not responsive to the needs of our users, are not appropriately timed with market opportunity, or are not effectively brought to market. As search technology continues to develop, there may be offered in the China market products and services that are, or that are perceived to be, substantially similar to or better than those generated by our search services. As worldwide focus on the development of AI technologies has intensified, it has become increasingly important to apply AI technologies to online search products and features in order to attract and retain users, and we cannot be sure that we will be able to apply such technologies successfully.

        Our competitors may develop and offer new products, services, and features that are similar to ours and may introduce them to the market before we can, and such new offerings from our competitors may be found by users to be more attractive than ours. Moreover, we cannot be sure that any of our new products, services, and features will attract additional users and lead to the generation of incremental revenue.

        As users increasingly use mobile devices to access search services and other Internet services in China, we will need to continue to design, develop, promote, and operate new products and services tailored for mobile devices. Our design and development of new products and services that are optimized for mobile devices may not be successful. We may encounter difficulties with the installation and delivery of such new products and services, and they may not function smoothly. As new mobile devices are released or updated, we may encounter problems in developing and upgrading our products and services for the new releases and updates, and we may need to devote significant resources to such development and upgrades. If we are not successful in adapting our offerings for mobile devices as described above, maintenance and growth of our business will be impeded.

If our collaboration with Tencent is terminated or curtailed, our business and prospects for growth will be adversely affected.

        We have extensive collaboration with Tencent, one of our largest shareholders. We are the default general search engine in various Tencent products that provide general search offerings, such as Mobile QQ Browser, qq.com , and the PC Web directories daohang.qq.com and hao.qq.com . Approximately 36.2% of our total search traffic, measured by page views, was contributed by Tencent's Internet properties in September 2017. Sogou Weixin Search is currently the sole general search engine with access to all content published on Weixin Official Accounts, but it is possible that Tencent will grant such access to other general search engines. We cannot assure you that we will be able to maintain the current level of cooperation with Tencent in the future. If our collaborative relationship with Tencent is terminated or curtailed due to Tencent's initiating its own general search service or partnering with other search engine companies, or if any of the commercial terms were to be revised or made less favorable to us, or if Tencent does not continue to deliver to us an adequate level of access to its platforms or adequately promote our products and services, our business and prospects will be adversely affected. For a detailed discussion of our collaborative arrangements with Tencent, see "Our Relationships with Sohu and Tencent."

Our efforts to expand our collaboration with Tencent may not be successful.

        In October 2017, Tencent began testing the integration of Sogou Search into Weixin/WeChat, whereby its users can use Sogou Search as a general search function from within Weixin/WeChat to access information outside Weixin/WeChat. Such an integration represents a key focus of our efforts to increase our user base by expanding our collaboration with Tencent, as Weixin/WeChat was the largest mobile community in China by MAU in September 2017, according to iResearch. We intend to discuss commercial arrangements with Tencent after completion of product testing and optimization. However, we cannot assure you that product testing will be successful or that we will be able to reach agreement with Tencent as to commercial terms that would apply to such an integration. If the integration of

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Sogou Search into Weixin/WeChat is not successful or, even if it is successful, if we are unable to agree with Tencent as to commercial terms and Tencent terminates the integration, we will lose the potential to expand our user base by offering general search services in Weixin/WeChat to its users, which would have an adverse impact on our prospects for growth. In addition, although Tencent has agreed that Sogou Search will be offered as the default general search engine for Tencent products that offer general search functions, such agreement will terminate as to Weixin/WeChat (and as to Tencent products other than Mobile QQ Browser and PC Web navigation products) after September 2018, rather than 2023, if Tencent is able to demonstrate that offering Sogou Search as the default general search engine will "harm the user experience." See "Related Party Transactions—Business Collaboration with Tencent." It is difficult for us to predict the potential impact of the inclusion of Sogou Search as the default general search engine in Weixin/WeChat measured under the standard of "harm the user experience." Even if our general search engine is integrated into Weixin/WeChat, the potential for growth of our business through such integration will be limited if Tencent does not make Sogou Search the default general search engine and a Tencent search engine or a search engine of one of our competitors is given priority over ours in Weixin/WeChat.

Our existing business and our expansion strategy depend on certain additional key collaborative arrangements, and any inability to maintain or develop such relationships could have an adverse effect on our business and prospects for growth.

        Our existing business, and our strategy for developing our business, involve maintaining and developing various types of collaborations with third parties, which provide us with access to additional user traffic, search services, products, and technology. For example, our Sogou Wise Doctor delivers healthcare information, and receives healthcare data, through partnerships that provide us with access to articles written by physicians and to a PRC-government sponsored healthcare encyclopedia; our partnership with Zhihu provides us with access to a knowledge-sharing platform; our partnership with Microsoft's Bing provides us with the technology to provide our users with English content on the Internet that we translate to Chinese in connection with our cross-language search service; and our partnership with China Literature enables our users to access literature from a large online collection. In addition, our various partnerships with third-party Internet properties provide our advertisers significant exposure to users beyond our core search user base. We consider these collaborations to be important to our ability to deliver attractive service, product, and content offerings to our users, in order to maintain and expand our user and advertiser bases, and we believe that it will continue to be important for us to develop similar partnerships in the future. Our inability to maintain and grow such relationships could have an adverse impact on our existing business and our growth prospects.

        We also have existing, and hope to develop additional, relationships with mobile device manufactures for pre-installation of our search, input method, and related applications. If we are unable to maintain and expand such relationships, the quality and reach of delivery of our services will be adversely affected, and it may also be difficult for us to maintain and expand our user base and enhance awareness of our brand. In addition, our competitors may establish the same relationships as those we have, which would tend to diminish any advantage we might otherwise gain from these relationships.

If we fail to maintain and expand our collaborations with third-party operators of Internet properties, our revenues and growth may be adversely affected.

        We place certain of our advertisers' promotional links on the Internet properties of third parties, thereby expanding the base of users accessing the advertisements beyond our own user base, and increasing our pay-for-click revenues. If these third parties decide to use a competitor's or their own online search services, or do not prominently display our advertisements in comparison to those of other advertisers on their properties, or if we fail to attract additional third-party operators of Internet properties, our advertising revenues and growth may be adversely affected.

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We may not be able to sustain our historical growth.

        We have grown significantly over a relatively short period. Our total search page views grew by 28.0%, and our mobile search page views grew by 71.9%, on an annualized basis from September 2014 to September 2017. Our revenues grew from US$386.4 million for the year ended December 31, 2014, to US$591.8 million for the year ended December 31, 2015, and to US$660.4 million for the year ended December 31, 2016. Our revenues grew from US$322.9 million for the six months ended June 30, 2016 to US$373.2 million for the six months ended June 30, 2017. However, while this represented revenue growth of 53.2% from 2014 to 2015, our revenue growth decreased to 11.6% from 2015 to 2016, as our 2016 revenues were affected by tightened PRC regulation of the online advertising industry during 2016, which had an adverse impact on the search and search-related advertising market in China in general. See "—Risks Related to China's Regulatory and Economic Environment—PRC regulations relating to sponsored search have had, and may continue to have, an adverse effect on our results of operations." We may not be able to sustain a rate of growth in future periods similar to that we experienced in the past, and our revenues may even decline. Accordingly, you should not rely on the results of any prior period as an indication of our future financial and operating performance.

We depend on online advertising for a significant majority of our revenues. If we fail to retain existing advertisers or attract new advertisers for our online advertising services, our business and growth prospects could be harmed.

        We earn most of our revenues from our search and search related advertising services. Advertisers will not use our services if they do not find them to be effective in producing a sufficient volume of click-throughs and desired results for advertisers. Our advertisers are generally able to terminate their relationships with us at any time without penalty if they are not satisfied with our services, choose our competitors for similar services, or advertise in media channels other than Internet search. Therefore, it could be difficult for us to maintain or increase our advertiser base, and our revenues and profits could decline or fail to increase.

We rely on third-party advertising agencies for most of our online advertising revenues.

        We rely heavily on third-party advertising agencies for our sales to our advertisers. It is important that we maintain good relationships with these agencies. We do not enter into long-term agreements with any of the advertising agencies and cannot assure that we will continue to maintain favorable relationships with them. Further, we provide various types of discounts and rebates to advertising agencies in order to incentivize them to maximize the volume of advertising business that they bring to us. In order to retain or properly incentivize our advertising agencies, it may become necessary in the future for us to increase the levels of such rebates and discounts, which could have an adverse effect on our results of operations.

If we fail to maintain and enhance awareness of and loyalty to our brand, it will be difficult for us to maintain and increase our user and advertiser bases.

        It is critical for us to maintain and further enhance our brand if we are to succeed in expanding our user and advertiser bases. Our success in promoting and enhancing our brand, and our ability to remain competitive, will depend on our success in delivering superior user experience and on our marketing efforts. Enhancing our brand awareness may require substantial marketing and promotion expenses. If we are unable to maintain and enhance our brand, or incur significant marketing and promotion expenses that do not achieve anticipated business growth, or are subject to negative publicity that harms our brand, our business and results of operations may be adversely affected.

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Our success depends on the continuing efforts of our senior management team and key employees, and our business may be harmed if we lose their services.

        Our business heavily depends upon the services of our key executives, particularly Xiaochuan Wang, our Chief Executive Officer. If any of our key executives is unable or unwilling to continue in his present position, joins a competitor, or forms a competing company, our business may be severely disrupted. Although executive officers have entered into employment agreements, confidentiality agreements, and non-competition agreements with us, the degree of protection afforded to an employer pursuant to confidentiality and non-competition undertakings by persons employed in the PRC may be more limited when compared to the degree of protection afforded with respect to employees in some other jurisdictions. We do not maintain key-man life insurance for any of our key executives.

        We also rely on key highly-skilled personnel for our business. Given the competitive nature of the industry, and in particular our competitors' increasingly aggressive efforts to provide competitive compensation packages to attract talent in the markets where we operate, it may be difficult for us to recruit and retain qualified personnel, and the risk of members of our key staff leaving us is high. Any such departure could have a disruptive impact on our operations, and if we are unable to recruit, retain and motivate key personnel, we may not be able to grow effectively.

Our strategy of investments in and acquiring complementary businesses and assets may fail, which could result in impairment losses.

        In addition to organic growth, we may take advantage of opportunities to invest in or acquire additional businesses, services, assets or technologies. However, we may fail to select appropriate investment or acquisition targets, or we may not be able to negotiate optimal arrangements, including arrangements to finance any acquisitions. Acquisitions and the subsequent integration of new assets and businesses into our own could require significant management attention and could result in a diversion of resources away from our existing business. Investments and acquisitions could result in the use of substantial amounts of cash, increased leverage, potentially dilutive issuances of equity securities, goodwill impairment charges, amortization expenses for other intangible assets and exposure to potential liabilities of the acquired business, and the invested or acquired assets or businesses may not generate the financial results we expect. Moreover, the costs of identifying and consummating these transactions may be significant. In addition to obtaining the necessary corporate governance approvals, we may also need to obtain approvals and licenses from relevant governmental authorities for the acquisitions to comply with applicable laws and regulations, which could result in increased costs and delays.

Requirements of U.S. GAAP regarding the recognition of share-based compensation expense may adversely affect our results of operations and our competitiveness in the employee marketplace.

        Our performance is largely dependent on talented and highly-skilled individuals. Our future success depends on our continuing ability to identify, develop, motivate, and retain highly-skilled personnel. We have a history of using low or nominally-priced employee share options as an important component of competitive pay packages, in order to align our employees' interests with the interests of our company and our shareholders and to encourage quality employees to join and remain with us. We have adopted guidance on accounting for share-based compensation that requires the measurement and recognition of compensation expense for all share-based compensation based on estimated fair values. As a result, our operating results contain charges for share-based compensation expense related to employee share options. The historical and future recognition of share-based compensation in our statements of comprehensive income has had and will have an impact on our results of operations. On the other hand, if we alter our employee share incentive plans to minimize the corresponding share-based compensation expense, it may limit our ability to continue to use share-based awards as a tool to attract and retain our employees, and it may adversely affect our operations. In addition, there

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may be future changes in the U.S. GAAP requirements for recognition of share-based compensation expense, which could have similar effects on our results operations and our competitiveness in the market for key employees.

Our user metrics and other estimates are subject to inherent challenges in measuring our operating performance, which may harm our reputation.

        We regularly review MAU, DAU, number of advertisers, page views, and other operating metrics to evaluate growth trends, measure our performance, and make strategic decisions. These metrics are calculated using internal company data, have not been validated by an independent third party, and may not be indicative of our future financial results. While these numbers are based on what we believe to be reasonable estimates for the applicable period of measurement, there are inherent challenges in measuring how our platforms are used across a large population in China. For example, we may not be able to distinguish individual users who have multiple accounts.

        Errors or inaccuracies in our metrics or data could result in incorrect business decisions and inefficiencies. For instance, if a significant understatement or overstatement of active users were to occur, we might expend resources to implement unnecessary business measures or fail to take required actions to remedy an unfavorable trend. If partners or investors do not perceive our user, geographic, or other operating metrics to accurately represent our user base, or if we discover inaccuracies in our user, geographic, or other operating metrics, our reputation may be harmed.

We have not independently verified the accuracy or completeness of data, estimates, and projections in this prospectus that we obtained from third party sources, and such information involves assumptions and limitations.

        Certain facts, forecasts, and other statistics relating to the industries in which we compete contained in this prospectus have been derived from various public data sources and a commissioned third-party industry report. In connection with this offering, we commissioned certain industry experts to provide information on market size and growth projections. In particular, we commissioned iResearch to conduct market research concerning the online search and AI industries in China, and IDC to conduct market research concerning the same industries in the United States. In deriving the market size of these industries, these industry consultants may have adopted different assumptions and estimates for certain metrics, such as MAU. While we generally believe such reports to be reliable, we have not independently verified the accuracy or completeness of such information. Such reports may not be prepared on a comparable basis or may not be consistent with other sources.

        Industry data and projections involve a number of assumptions and limitations. Our industry data and market share data should be interpreted in light of the defined industries in which we operate. Any discrepancy in the interpretation of such data could lead to different measurements and projections, and actual results could differ from the projections.

We may not be able to prevent others from making unauthorized use of our intellectual property, which could harm our business and competitive position.

        We regard our patents, copyrights, trademarks, trade secrets, and other intellectual property as critical to our business. Unauthorized use of our intellectual property by third parties may adversely affect our business and reputation. We rely on a combination of intellectual property laws and contractual arrangements to protect our proprietary rights. It is often difficult to register, maintain, and enforce intellectual property rights in the PRC. Statutory laws and regulations are subject to judicial interpretation and enforcement and may not be applied consistently due to the lack of clear guidance on statutory interpretation in the PRC. In addition, contractual agreements may be breached by counterparties, and there may not be adequate remedies available to us for any such breach. Accordingly, we may not be able to effectively protect our intellectual property rights or to enforce our

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contractual rights in China. Policing any unauthorized use of our intellectual property is difficult and costly and the steps we have taken may be inadequate to prevent the misappropriation of our intellectual property. In the event that we resort to litigation to enforce our intellectual property rights, such litigation could result in substantial costs and a diversion of our managerial and financial resources. We can provide no assurance that we will prevail in such litigation. In addition, our trade secrets may be leaked or otherwise become available to, or be independently discovered by, our competitors.

Pending or future litigation could have an adverse impact on our financial condition and results of operations.

        The online search industry in China is highly competitive and litigious. From time to time, we have been, and may in the future be, subject to lawsuits brought by our competitors, individuals, or other entities against us. We are currently involved in several lawsuits in PRC courts where our competitors instituted proceedings or asserted counterclaims against us and we instituted proceedings or asserted counterclaims against our competitors. For example, there are various legal proceedings currently pending between us and Baidu in which we allege that Baidu's input method infringes certain of our patents relating to Sogou Input Method and seek monetary damages, while Baidu has asserted in counterclaims or in legal proceeding that it has initiated against us that Sogou Input Method infringes certain of its patents, and seeks monetary damages. In addition, we are subject to ongoing unfair competition claims against us brought by Baidu, UCWeb, and Qihoo 360 Technology Co., Ltd., or Qihoo360, separately, in which they allege that certain functions of our Sogou Input Method unfairly divert users to us, and seek monetary damages and cessation of the alleged unfair competitive practices.

        Where we can make a reasonable estimate of the liability relating to pending litigation against us and determine that an adverse liability resulting from such litigation is probable we record a related contingent liability. As additional information becomes available, we assess the potential liability and revise estimates as appropriate. However, due to the inherent uncertainties relating to litigation, the amount of our estimates may be inaccurate, in which case our financial condition and results of operation may be adversely affected. In addition, the outcomes of actions we institute may not be successful or favorable to us. Lawsuits against us may also generate negative publicity that significantly harms our reputation, which may adversely affect our user and advertiser base. In addition to the related cost, managing and defending litigation and related indemnity obligations can significantly divert our management's and Board of Directors' attention from operating our business. We may also need to pay damages or settle lawsuits with a substantial amount of cash. While we do not believe that any currently pending proceedings are likely to have a material adverse effect on our business, financial condition, results of operations, and cash flows, if there were adverse determinations in legal proceedings against us, we could be required to pay substantial monetary damages or adjust our business practices, which could have an adverse effect on our financial condition and results of operations, and cash flows.

We are currently subject to, and in the future may from time to time face, intellectual property infringement claims, which could be time-consuming and costly to defend, and could have an adverse impact our financial position and results of operations, particularly if we are required to pay significant damages or cease offering any of our products or curtail any key features of our products.

        We cannot be certain that the products, services and intellectual property used in our normal course of business do not or will not infringe valid patents, copyrights or other intellectual property rights held by third parties. We currently are, and may in the future be, subject to claims and legal proceedings relating to the intellectual property of others in the ordinary course of our business, and may in the future be required to pay damages or to agree to restrict our activities. See "—Pending or future litigation could have an adverse impact on our financial condition and results of operations." In particular, if we are found to have violated the intellectual property rights of others, we may be

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enjoined from using such intellectual property, may be ordered to pay damages, and may incur licensing fees or be forced to develop alternatives. We may incur substantial expense in defending against third-party infringement claims, regardless of their merit. Successful infringement claims against us may result in substantial monetary liability or may materially disrupt the conduct of our business by restricting or prohibiting our use of the intellectual property in question.

We may not have exclusive rights to technology, trademarks, and designs that are crucial to our business.

        We have applied for various patents relating to our business. While we have succeeded in obtaining some patents, some of our patent applications are still under examination by the State Intellectual Property Office of the PRC. Approvals of our patent applications are subject to determinations by the State Intellectual Property Office of the PRC and relevant overseas authorities that there are no prior rights in the applicable territory. In addition, we have applied for initial registrations in the PRC and overseas, and/or changes in registrations relating to transfers of our Sogou logos and other of our key trademarks in the PRC, and the corresponding Chinese versions of the trademarks, so as to establish and protect our exclusive rights to these trademarks. While we have succeeded in registering the trademarks for most of these marks in the PRC under certain classes, the applications for initial registration, and/or changes in registrations relating to transfers, of some marks and/or of some of trademarks under other classes are still under examination by the Trademark Office of the State Administration for Industry and Commerce, or SAIC, and relevant overseas authorities. Approvals of our initial trademark registration applications, and/or of changes in registrations relating to such transfers, are subject to determinations by the Trademark Office of the SAIC and relevant overseas authorities that there are no prior rights in the applicable territories. We cannot assure you that these patent and trademark applications will be approved. Any rejection of these applications could adversely affect our rights to the affected technology, marks, and designs. In addition, even if these applications are approved, we cannot assure you that any issued patents or registered trademarks will be sufficient in scope to provide adequate protection of our rights.

If our search results contain information that is inaccurate or harmful to our users, our business and reputation may be adversely affected.

        We could be exposed to liability arising from our search results listings if information accessed through our services contains errors, and third parties may make claims against us for losses incurred in reliance on that information. Investigating and defending such claims could be expensive, even if they did not result in liability and we do not carry any liability insurance against such risks.

        In addition, if users do not perceive information that they access through our search services to be authoritative, useful, and trustworthy, we may not be able to retain these users or attract additional users, and our reputation, business, and results of operation may be harmed. In addition, if such content contains inaccuracies, it is possible that users will seek to hold us liable for damages, because we provide links to such content, even though such content is provided by third parties and any negative publicity regarding the accuracy of such content could harm our reputation, and reduce user traffic. In addition, any negative publicity or incident involving our peer companies could have an adverse impact on our industry as a whole, which in turn could harm our reputation and reduce our user traffic. For example, in early 2016 it was widely reported that an unsuccessful experimental cancer treatment had been promoted in a sponsored search listing on third party's Internet property. Even though our search results listings were not involved, we believe that the broad negative publicity surrounding the incident adversely affected the reputation of the online search industry in China in general with an adverse impact on our user traffic and results of operations in 2016.

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We may be subject to regulatory investigations and sanctions for inappropriate or illegal content that is accessed through our search results.

        The online search industry in China is subject to extensive regulation. If content accessed through our search services includes information that PRC governmental authorities find illegal or inappropriate, we may be required to curtail or even shut down our search services, and we may be subject to other penalties. Although we seek to prevent fraudulent or otherwise illegal or inappropriate websites and information from being included in our search results, such measures may not be effective. See "—Risks Related to China's Regulatory and Economic Environment—Regulation and censorship of information distribution in China may have an adverse effect on our business"; and "—Risks Related to China's Regulatory and Economic Environment—The PRC government may prevent us from distributing, and we may be subject to liability for, content that it believes is inappropriate."

We may be subject to potential liability for claims that search results violate the intellectual property rights of third parties.

        It is possible that content that is made available by us through our search results may violate the intellectual property rights of third parties. PRC laws and regulations are evolving, and uncertainties exist with respect to the legal standards for determining the potential liability of online search service providers for search results that provide links to content on third-party websites that infringes copyrights of third parties. In December 2012, the Supreme People's Court of the PRC promulgated a judicial interpretation providing that PRC courts will place the burden on Internet service providers to remove not only links or content that has been specifically-mentioned in notices of infringement from persons and entities claiming copyright in such content, but also links or content that the providers "should have known" contained infringing content. This interpretation could subject us to significant administrative burdens and might expose us to civil liability and penalties. Further, we rely on content provided by professional researchers and writers, either developed by the outlets themselves or adapted from content of parties separate from such outlets, and it is difficult for us to fully monitor such content, which could make us more vulnerable to potential infringement claims.

We may be subject to legal liability associated with online activities on our platforms.

        We host and provide a wide variety of products and services that enable advertisers to advertise products and services, and users to exchange information and engage in various online activities. We may be subject to claims, investigations, or negative publicity relating to such activities. PRC laws and regulations relating to the liability of providers of online products and services for activities of their users are undeveloped, and their current and future reach are unclear. We also place advertisements on third-party Internet properties, and we offer products and services developed or created by third parties. We may be subject to claims concerning these products and services based on our involvement in providing access to them, even if we do not offer the products and services directly. We could be required to spend considerable financial and managerial resources defending any such claims, and they could result in our having to pay monetary damages or penalties or ceasing certain aspects of our business, which could have an adverse effect on our business and results of operations.

Privacy concerns or security breaches relating to our platforms could damage our reputation, deter current and potential users and advertisers from using our products and services, and expose us to legal penalties and liability.

        We collect, process, and store on our servers significant amounts of data concerning our users. While we have taken steps to protect our user data, our security measures could be compromised, because techniques used to sabotage or obtain unauthorized access to systems change frequently and generally are not recognized until they are launched against a target, and we may be unable to

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anticipate these techniques or to implement adequate preventative measures. In addition, we are subject to various regulatory requirements relating to the security and privacy of such data, including restrictions on the collection and use of personal information of users and steps we must take to prevent personal data from being divulged, stolen, or tampered with. Regulatory requirements regarding the protection of such data are constantly evolving and can be subject to significant change, making the extent of our responsibility in that regard uncertain. For example, the PRC Cybersecurity Law became effective in June 2017, but it is unclear as to the circumstances and standard under which the law would apply and violations would be found, and there are great uncertainties as to the interpretation and application of the law. It is possible that our data protection practice is or will be inconsistent with regulatory requirements. See "PRC Regulation—Provision of Internet Content—Information Security and Censorship." Complying with such requirements could cause us to incur substantial expenses or to alter or change our practice in a manner that could harm our business. Any systems failure or compromise of our security, including through employee error, that results in the release of our user data could seriously harm our reputation and brand, impair our ability to retain and attract users and advertisers, expose us to liability to users whose data is released, and subject us to sanctions and penalties from regulatory authorities. We also could be liable for any security breaches of our advertisers' confidential information. Any security breaches exposing such information could damage our reputation and deter current and potential users and advertisers from using our services.

Our network operations may be vulnerable to hacking and viruses, which may reduce the use of our products and services and expose us to liability.

        Our user traffic may decline if any well-publicized compromise of security occurs. "Hacking" involves efforts to gain unauthorized access to information or systems or to cause intentional malfunctions or loss or corruption of data, software, hardware, or other computer equipment. Techniques used by hackers to obtain unauthorized access or sabotage systems change frequently and often are not recognized until launched against a target, which means that we may be unable to anticipate new hacking methods or implement adequate security measures. Hackers, if successful, could misappropriate proprietary information or cause disruptions in our service. We may be required to expend capital and other resources to protect our Internet platforms against hackers, and measures we may take may not be effective. In addition, the inadvertent transmission of computer viruses could expose us to a risk of loss or litigation and possible liability, as well as damage our reputation and decrease our user traffic.

Our business may be adversely affected by third-party software applications or practices that interfere with our receipt of information from, or provision of information to, our users, which may impair our users' experience.

        Our business may be adversely affected by third-party software applications, which may be unintentional or malicious, that make changes to our users' PCs or mobile devices and interfere with our products and services. These software applications may change our users' experience by hijacking queries, altering or replacing our search results, or otherwise interfering with our ability to connect with our users. Such interference can occur without disclosure to or consent from users, and users may associate any resulting negative experience with our products and services. Such software applications are often designed to be difficult to remove, block, or disable. Further, software loaded on or added to mobile devices on which our search or other applications, such as Sogou Input Method, are pre-installed may be incompatible with or interfere with or prevent the operation of such applications, which might deter the owners of such devices from using our services.

        In addition, third-party website owners, content providers, and developers may implement applications and systems that interfere with our ability to crawl and index their webpages and content, which is critical to the operation of our search services. If we are unable to successfully prevent or limit

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any such applications or systems that interfere with our products and services, or if a significant number of third-party website owners, content providers, and developers prevent us from indexing and including their webpages and content in our search results, our ability to deliver high-quality search results and a satisfactory user experience will be impeded.

Adoption of Internet advertisement blocking technologies may have an adverse impact on our business and results of operations.

        The development of software that blocks Internet advertisements before they appear on a user's screen may hinder the growth of online advertising. Since our advertising revenues are generally based on user click-throughs, the expansion of advertisement-blocking on the Internet may decrease our advertising revenues, because when advertisements are blocked they are not downloaded from the server, which means such advertisements will not be tracked as a delivered advertisement. In addition, advertisers may choose not to advertise on the Internet or on or through our sites because of the use by third parties of Internet advertisement blocking measures. In addition, increasing numbers of browsers include technical barriers designed to prevent Internet information service providers such as us to track the browsing history of their Internet users, which is also likely to adversely affect the growth of online advertising and hence our business and growth prospects.

If we fail to detect click-through fraud, we could lose the confidence of our advertisers and our revenues could decline.

        Our business is exposed to the risk of click-through fraud on our paid search results. Click-through fraud occurs when a person clicks paid search results for a reason other than to view the underlying content of search results. If we fail to detect significant fraudulent clicks or otherwise are unable to prevent significant fraudulent activity, the affected search advertisers may experience a reduced return on their investment in our pay-for-click services and lose confidence in the integrity of our pay-for-click service systems, and we may have to issue refunds to our advertisers and may lose their future business. If this happens, we may be unable to retain existing advertisers and attract new advertisers for our pay-for-click services, and our search revenues could decline. In addition, affected advertisers may also file legal actions against us claiming that we have over-charged or failed to refund them. Any such claims or similar claims, regardless of their merit, could be time-consuming and costly for us to defend against and could also adversely affect our brand and our search advertisers' confidence in the integrity of our pay-for-click services and systems.

Web spam and content farms, as well as our attempts to block them, could decrease the quality of our search results, and could deter our current and potential users from using our products and services.

        The proliferation of search engine spam websites, commonly referred to as Web spam, which attempt to manipulate search indexing to cause them to appear higher in search results ranking hierarchies than they would without such manipulation, can have the effect of weakening the integrity of our search results and causing users to lose confidence in our search products and services. "Content farm" websites, which commission very large amounts of content, often of low quality, for the purpose, similar to that of Web spam, of causing such content farms' links to obtain relatively high ranking in Internet providers' search results, can have similar adverse effects.

        While we use, and continually improve, technology designed to detect and block Web spam, the algorithms we apply may nevertheless result in excessive filtering that blocks desirable websites from our search results. Therefore, both the existence of Web spam and content farms, and our attempts to block them, could deter our current and potential users from using our products and services. In addition, as some of our third-party Internet-property collaborators could include Web spam or content farm websites, our advertising revenues could be reduced by our efforts to filter such websites. If our efforts to combat these and other types of index spamming are unsuccessful, our reputation for

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delivering relevant information could be diminished. This could result in a decline in user traffic, which would damage our business.

The successful operation of our business depends upon the performance and reliability of the Internet infrastructure in China.

        Our growth will depend in part on the PRC government and state-owned telecommunications services providers maintaining and expanding Internet and telecommunications infrastructure, standards, protocols, and complementary products and services to facilitate our reaching a broader base of Internet users in China.

        Almost all access to the Internet in China is maintained through China Mobile, China Unicom and China Telecom under the administrative control and regulatory supervision of the MIIT. We rely on this infrastructure and China Mobile, China Unicom, and China Telecom to provide data communications capacity primarily through local telecommunications lines. Although the government has announced aggressive plans to develop the national information infrastructure, this infrastructure may not be developed and the Internet infrastructure in China may not be able to support the continued growth of Internet usage. In addition, we will be unlikely to have access to alternative networks and services on a timely basis, if at all, in the event of any infrastructure disruption or failure.

Interruption or failure of our information technology and communications systems may result in reduced user traffic and harm to our reputation and business.

        Interruption or failure of any of our information technology and communications systems or those of the operators of third-party Internet properties with which we collaborate could impede or prevent our ability to provide our search and search-related services. In addition, our operations are vulnerable to natural disasters and other events. Our disaster recovery plan for our servers cannot fully ensure safety in the event of damage from fire, floods, typhoons, earthquakes, power loss, telecommunications failures, hacking, and similar events. If any of the foregoing occurs, we may experience a partial or complete system shutdown. Furthermore, our servers, which are hosted at third-party Internet data centers, are also vulnerable to break-ins, sabotage and vandalism. Some of our systems are not fully redundant, and our disaster recovery planning does not account for all possible scenarios. The occurrence of a natural disaster or a closure of an Internet data center by a third-party provider without adequate notice could result in lengthy service interruptions.

        Any system failure or inadequacy that causes interruptions in the availability of our services, or increases the response time of our services, could have an adverse impact on our users' experience and reduce our users' satisfaction, our attractiveness to users and advertisers, and future user traffic and advertising on our platform.

        Furthermore, we do not carry any business interruption insurance. To improve the performance and to prevent disruption of our services, we may have to make substantial investments to deploy additional servers or one or more copies of our Internet platforms to mirror our online resources.

We face risks related to natural disasters, health epidemics, or terrorist attacks.

        Our business could be adversely affected by natural disasters, such as earthquakes, floods, landslides, and tsunamis, outbreaks of health epidemics such as an outbreak of avian influenza; severe acute respiratory syndrome, or SARS; Zika virus; or Ebola virus, as well as terrorist attacks, other acts of violence or war, or social instability. If any of these occurs, we may be required to temporarily or permanently close and our business operations may be suspended or terminated.

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Risks Related to Our Corporate Structure

In order to comply with PRC regulatory requirements, we operate a portion of our business through our primary VIE, Sogou Information, a company with which we have contractual relationships but in which we do not have an actual ownership interest, and its three direct and indirect wholly-owned subsidiaries. If these contractual arrangements and our current ownership structure were found to be in violation of current or future PRC laws and regulations we could be subject to severe penalties.

        Various regulations in the PRC restrict or prohibit foreign-owned companies from operating in specified industries, such as the provision of Internet information, online games, mobile applications, Internet access, and certain other industries. As we are a Cayman Islands company and our direct and indirect wholly-owned subsidiaries Sogou BVI, Sogou HK, and Vast Creation are incorporated in the British Virgin Islands and Hong Kong, our indirect wholly-owned PRC subsidiaries, Beijing Sogou Technology Development Co., Ltd., or Sogou Technology, and Beijing Sogou Network Technology Co., Ltd. or Sogou Network, are wholly foreign-owned enterprises, or WFOEs, under PRC law and are considered to be foreign-owned. In order to comply with PRC regulatory requirements, we conduct certain of our Internet and other value-added telecommunication operations in the PRC through our VIE Sogou Information, which is incorporated in the PRC and is owned 10% by our Chief Executive Officer, 45% by our controlling shareholder Sohu, and 45% by a Tencent group entity; and through three direct and indirect subsidiaries of Sogou Information, which are also considered to be our VIEs. Through a series of contractual arrangements, Sogou Information, of which we are the primary beneficiary, and Sogou Information's three direct and indirect subsidiaries are effectively controlled by our subsidiary Sogou Technology. Revenues generated by our VIEs represented 18.6%, 18.6%, 24.1%, and 25.9%, respectively, of our total revenues for the years ended December 31, 2014, 2015, and 2016 and for the six months ended June 30, 2017.

        On January 19, 2015, Ministry of Commerce, or MOFCOM, released on its Website for public comment a proposed PRC law, or the Draft FIE Law, that could be interpreted to include VIEs within the scope of entities that could be considered to be foreign invested enterprises, or FIEs, that would be subject to restrictions under existing PRC laws on foreign investment in certain categories of industry. Specifically, the Draft FIE Law introduces the concept of "actual control" for determining whether an entity is considered to be an FIE. In addition to control through direct or indirect ownership or equity, the Draft FIE Law includes control through contractual arrangements within the definition of "actual control." If the Draft FIE Law is passed by the People's Congress of the PRC and goes into effect in its current form, these provisions regarding control through contractual arrangements could be construed to reach our VIE arrangements, and as a result our VIEs could become explicitly subject to the current restrictions on foreign investment in certain categories of industry. The Draft FIE Law includes provisions that would exempt from the definition of foreign invested enterprises entities where the ultimate controlling shareholders are either entities organized under PRC law or individuals who are PRC citizens. The Draft FIE Law is silent as to what type of enforcement action might be taken against existing VIEs, such as ours, that operate in restricted or prohibited industries and are not controlled by entities organized under PRC laws or individuals who are PRC citizens. There remain significant uncertainties as to how various provisions of the Draft FIE Law might be interpreted. If the restrictions and prohibitions on FIEs included in the Draft FIE Law are enacted and enforced in their current form, our ability to use our VIE arrangements and our ability to conduct business through them could be severely limited.

        In addition, pursuant to Circular 6 and the MOFCOM Security Review Rules, a security review is required for mergers and acquisitions by foreign investors having "national defense and security" concerns and mergers and acquisitions by which foreign investors may acquire "de facto control" of domestic enterprises with "national security" concerns and prohibit foreign investors from bypassing the security review requirement by structuring transactions through proxies, trusts, indirect investments, leases, loans, control through contractual arrangements, or offshore transactions. These national

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security review-related regulations are relatively new and there is a lack of clear statutory interpretation regarding the implementation of the rules. PRC governmental authorities may interpret these regulations to mean that the transactions implementing our VIE structures should have been submitted for review. For a discussion of these PRC national security review requirements, see "PRC Regulation—Regulation of M&A and Overseas Listings."

        In the opinion of Commerce & Finance Law Offices, our PRC legal counsel, our current ownership structure, the ownership structure of our PRC subsidiaries and VIEs and the contractual arrangements between our PRC subsidiaries, VIEs and its shareholders are in compliance with existing PRC laws, rules, and regulations. Our PRC legal counsel also advises us that there are uncertainties regarding the interpretation and application of current or future PRC laws and regulations. Accordingly, we and our PRC legal counsel cannot assure you that the PRC regulatory authorities will not ultimately take a view contrary to that of our PRC legal counsel. If we were found to be in violation of any existing or future PRC laws or regulations relating to foreign ownership of value-added telecommunications businesses, online search services, online games, and other online information and content services, including the Draft FIE Law if it becomes effective, and security reviews of foreign investments in such businesses, regulatory authorities with jurisdiction over the operation of our business would have broad discretion in dealing with such a violation, including levying fines, confiscating our income, revoking the business or operating licenses of our PRC subsidiaries and/or VIEs, requiring us to restructure our ownership structure or operations, requiring us to discontinue or divest ourselves of all or any portion of our operations or assets, restricting our right to collect revenues, blocking our Internet platforms, or imposing additional conditions or requirements with which we may not be able to comply. Any of these actions could cause significant disruption to our business operations and have an adverse impact on our business, financial conditions, and results of operations. Further, if changes were required to be made to our ownership structure, our ability to consolidate our VIEs' assets and operating results into our consolidated financial statements could be adversely affected.

We depend upon contractual arrangements with our VIE Sogou Information and its shareholders for the success of our business and these arrangements may not be as effective in providing operational control as direct ownership of the entities and may be difficult to enforce.

        Due to the restrictions or prohibitions on foreign ownership over online search services, online games operations and other value-added telecommunication business in the PRC, we depend on our VIEs, in which we have no direct ownership interest, to provide those services through contractual agreements with our VIE Sogou Information and to hold some of our assets, including some of the domain names and trademarks relating to our business. These arrangements may not be as effective in providing control over our business operations as would direct ownership of our VIEs. For example, if we had direct ownership of our VIEs, we would be able to exercise our rights as a shareholder to effect changes in their boards of directors, which in turn could effect changes at the management level. Due to our VIE structure, we have to rely on contractual rights to affect control and management of our VIEs, which exposes us to the risk of potential breach of VIE contracts by the VIEs or their shareholders, such as their failing to use the domain names and trademarks held by them, or failing to maintain our Internet platforms, in an acceptable manner or taking other actions that are detrimental to our interests. In addition, as our VIE Sogou Information is jointly owned by its shareholders, it may be difficult for us to change our corporate structure if such shareholders refuse to cooperate with us. In addition, some of our subsidiaries and VIEs could fail to take actions required for our business, such as entering into business contracts with potential suppliers or failing to maintain the necessary permits for the business. Furthermore, if the shareholders of Sogou Information were involved in proceedings that had an adverse impact on their shareholder interests in Sogou Information or on our ability to enforce relevant contracts related to the VIE structure, our overall business, financial conditions, and results of operations could be adversely affected.

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        The shareholders of Sogou Information may breach, or cause Sogou Information to breach, the VIE contracts for a number of reasons. For example, their interests as shareholders of Sogou Information and the interests of our subsidiaries may conflict and we may fail to resolve such conflicts; the shareholders may believe that breaching the contracts will lead to greater economic benefit for them; or the shareholders may otherwise act in bad faith. If any of the foregoing were to happen, we may have to rely on legal or arbitral proceedings to enforce our contractual rights. In addition, disputes may arise among the shareholders of Sogou Information with respect to their ownership of Sogou Information, which could lead them to breach their agreements with us. Such arbitral and legal proceedings and disputes may cost us substantial financial and other resources, and result in disruption of our business, and the outcome might not be in our favor. For example, a PRC court or arbitration panel could conclude that our VIE contracts violate PRC laws or are otherwise unenforceable. If the contractual arrangements with Sogou Information were found by PRC governmental authorities with appropriate jurisdiction to be unenforceable, we could lose control over the assets owned by Sogou Information and our other VIEs and lose our ability to consolidate such VIEs' results of operations, assets, and liabilities in our consolidated financial statements and/or to transfer the revenues of our VIEs to our corresponding PRC subsidiary Sogou Technology.

        As all of the contractual arrangements with Sogou Information and its shareholders are governed by PRC laws and provide for the resolution of disputes through either arbitration or litigation in the PRC, they would be interpreted in accordance with PRC laws and any disputes would be resolved in accordance with PRC legal procedures. We would have to rely for enforcement on legal remedies under PRC laws, including specific performance, injunctive relief, or damages, which might not be effective. For example, if we sought to enforce the equity interest purchase right agreement for the transfer of equity interests in Sogou Information, if the transferee was a foreign company the transfer would be subject to approval by PRC governmental authorities such as the MIIT and the MOFCOM, and the transferee would be required to comply with various requirements, including qualification and maximum foreign shareholding percentage requirements. As these PRC governmental authorities have wide discretion in granting such approvals, we could fail to obtain such approvals. In addition, our VIE contracts might not be enforceable in China if PRC governmental authorities, courts or arbitral tribunals took the view that such contracts contravened PRC laws or were otherwise not enforceable for public policy reasons.

        Furthermore, the legal environment in the PRC is not as developed as in other jurisdictions, such as the United States. As a result, uncertainties in the PRC legal system could further limit our ability to enforce these contractual arrangements. In the event we were unable to enforce these contractual arrangements, we would not be able to exert effective control over our VIEs, and our ability to conduct our business, and our financial conditions and results of operation would be severely adversely affected.

The contractual arrangements between our subsidiary Sogou Technology and our VIE Sogou Information may result in adverse tax consequences to us.

        PRC laws and regulations emphasize the requirement of an arm's-length basis for transfer pricing arrangements between related parties. The laws and regulations also require enterprises with related party transactions to prepare transfer pricing documentation to demonstrate the basis for determining pricing, the computation methodology and detailed explanations. Related party arrangements and transactions may be subject to challenge or tax inspection by PRC tax authorities.

        Under a tax inspection, if our transfer pricing arrangements between our China-based subsidiary Sogou Technology and our VIE Sogou Information are judged as tax avoidance, or related documentation does not meet the requirements for such arrangements, Sogou Information and Sogou Technology may be subject to adverse tax consequences, such as a transfer pricing adjustment. A transfer pricing adjustment could result in a reduction, for PRC tax purposes, of adjustments recorded by Sogou Information, which could adversely affect us by (i) increasing Sogou Information's tax

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liabilities without reducing Sogou Technology's tax liabilities, which could further result in interest and penalties being levied on us for unpaid taxes or (ii) limiting the ability of our PRC companies to maintain preferential tax treatment and other financial incentives. In addition, if for any reason we need to cause the transfer of any of the shareholders' equity interest in any Sogou Information to a different nominee shareholder, we might be required to pay individual income tax, on behalf of the transferring shareholder, on any gain deemed to have been realized by such shareholder on such transfer.

If one or more of our VIEs declare bankruptcy or become subject to a dissolution or liquidation proceeding, we may lose the ability to use and enjoy assets held by those VIEs.

        Our VIEs holds assets, such as our core intellectual property, licenses, and permits, that are critical to our business operations. Although the equity interest purchase rights agreement among our PRC subsidiaries, our VIE Sogou Information, and the shareholders of our Sogou Information contains terms that specifically obligate such shareholders to ensure the valid existence of Sogou Information and our other VIEs, in the event these shareholders breached their obligations and voluntarily liquidated our VIEs, or if any of our VIEs declared bankruptcy and all or part of its assets became subject to liens or rights of third-party creditors, we might be unable to continue some or all of our business operations. Furthermore, if any of our VIEs were to undergo a voluntary or involuntary liquidation proceeding, their shareholders or unrelated third-party creditors might claim rights to some or all of such VIEs' assets and their rights could be senior to our rights under the VIE contracts with Sogou Information, which could hinder our ability to operate our business.

Risks Related to China's Regulatory and Economic Environment

PRC regulations relating to sponsored search have had, and may continue to have, an adverse effect on our results of operations.

        On April 13, 2016, the SAIC and sixteen other PRC government agencies jointly issued a Notice of Campaign to Crack Down on Illegal Internet Finance Advertisements and Other Financial Activities in the Name of Investment Management, or the Campaign Notice, pursuant to which a campaign was conducted between April 2016 and January 2017 targeting, among other things, online advertisements for Internet finance and other financial activities posted on online search portals such as ours. The Cyberspace Administration of China, or the CAOC, issued the Interim Measures for the Administration of Online Search, or the CAOC Interim Measures, which became effective on August 1, 2016 and require that providers of online search services verify the credentials of pay-for-click advertisers, specify a maximum percentage that pay-for-click search results may represent of results on a search page, and require that providers of search services conspicuously identify pay-for-click search results as such. The SAIC issued the Interim Measures for the Administration of Online Advertising, or the SAIC Interim Measures, which became effective on September 1, 2016 and treat pay-for-click search results as advertisements subject to PRC laws governing advertisements, require that pay-for-click search results be conspicuously identified on search result pages as advertisements and subject revenues from such advertisements to a 3% PRC tax that is applied to advertising revenues. In order to comply with these regulations, we have established more stringent standards for selecting advertisers for our pay-for-click services and have turned down certain existing advertisers, and have lowered the percentage that pay-for-click search results represent of results on our search pages, which had an adverse impact on our search and search-related revenues and overall results of operations for 2016 and, along with the tax on advertising, are likely to continue to have such an impact. We cannot assure you that the PRC governmental authorities will not issue new laws or regulations specifically regulating sponsored search services, which could further impact our revenues.

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Political, economic, and social policies of the PRC government could affect our business.

        Substantially all of our business, operating assets, fixed assets and operations are located in China, and substantially all of our revenues are derived from our operations in China. Accordingly, our business may be adversely affected by changes in political, economic or social conditions in China, adjustments in PRC government policies or changes in laws and regulations.

        The economy of China differs from the economies of most countries belonging to the Organization for Economic Cooperation and Development in a number of respects, including:

•

structure;



•

level of government involvement;



•

level of development;



•

level of capital reinvestment;



•

growth rate;



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control of foreign exchange; and



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methods of allocating resources.

        Since 1949, China has been primarily a planned economy subject to a system of macroeconomic management. Although the PRC government still owns a significant portion of the productive assets in China, economic reform policies since the late 1970s have emphasized decentralization, autonomous enterprises and the utilization of market mechanisms. We cannot predict the future effects of the economic reform and macroeconomic measures adopted by the PRC government on our business or results of operations. Furthermore, the PRC government began to focus more attention on social issues in recent years and has promulgated or may promulgate additional laws or regulations in this area, which could affect our business in China.

        While the Chinese economy has grown significantly in the past 35 years, the growth has been uneven geographically among various sectors of the economy, and during different periods. The Chinese economy may not continue to grow, and if there is growth, such growth may not be steady and uniform; if there is a slowdown, such a slowdown may have a negative effect on our business. The Chinese economy experienced high inflation in 2010 and 2011, and to curb the accelerating inflation the PBOC, China's central bank, raised benchmark interest rates three times in 2011. The level of exports from the PRC also declined significantly recently. According to the National Bureau of Statistics of China, the growth rate of China's gross domestic product, compared to that of the same period in the previous year, slowed from 7.5% in 2012, to 7.7% in 2013, to 7.4% in 2014, to 6.9% in 2015, and to 6.7% in 2016. Various macroeconomic measures and monetary policies adopted by the PRC government to guide economic growth and manage inflation and the allocation of resources may not be effective in sustaining the growth rate of the Chinese economy. In addition, such measures, even if they benefit the overall Chinese economy in the long run, may have an adverse effect on us if they reduce the amount of money that our existing or future advertisers devote to online advertising.

The PRC legal system embodies uncertainties that could limit the legal protections available to us and you, or could lead to penalties on us.

        The PRC legal system is a civil law system based on written statutes and regulations. Unlike common law systems, it is a system in which decided legal cases have little precedential value. In 1979, the PRC government began to promulgate a comprehensive system of laws and regulations governing economic matters in general. Our PRC operating subsidiaries Sogou Technology and Sogou Network are WFOEs that are incorporated in China and wholly owned by our indirect offshore subsidiaries. As WFOEs, Sogou Technology and Sogou Network are subject to laws and regulations applicable to

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foreign investment in China. All of our subsidiaries and VIEs incorporated in China are also subject to all other applicable PRC laws and regulations. Because of the relatively short period for enacting such a comprehensive legal system, it is possible that the laws, regulations and legal requirements are relatively recent, and their interpretation and enforcement involve uncertainties. These uncertainties could limit the legal protections available to us and other foreign investors, including you. Such uncertainties may also make it easier for others to infringe our intellectual property without significant cost, and new entrants to the market may tend to use gray areas to compete with us. In addition, uncertainties in the PRC legal system may lead to penalties imposed on us because of a difference in interpretation of the applicable laws between the relevant PRC governmental authorities and us. For example, under current tax laws and regulations, we are responsible for paying value-added tax. However, since there is no clear guidance as to the applicability of certain areas of preferential tax treatment, we may be found to be in violation of the tax laws and regulations based on the interpretation of competent PRC tax authorities with regard to the scope of taxable services and the applicable tax rates, and therefore might be subject to penalties, including monetary penalties. In addition, we cannot predict the effect of future developments in the PRC legal system, particularly with regard to the Internet, including the promulgation of new laws, changes to existing laws or the interpretation or enforcement thereof, or the preemption of local regulations by national laws.

The enforcement of the PRC Labor Contract Law and other labor-related regulations in the PRC may adversely affect our business and results of operations.

        The Standing Committee of the National People's Congress enacted the Labor Contract Law in 2008, and amended it on December 28, 2012. The Labor Contract Law introduced specific provisions related to fixed-term employment contracts, part-time employment, probationary periods, consultation with labor unions and employee assemblies, employment without a written contract, dismissal of employees, severance, and collective bargaining to enhance previous PRC labor laws. Under the Labor Contract Law, an employer is obligated to sign an unlimited-term labor contract with any employee who has worked for the employer for ten consecutive years. Further, if an employee requests or agrees to renew a fixed-term labor contract that has already been entered into twice consecutively, the resulting contract, with certain exceptions, must have an unlimited term, subject to certain exceptions. With certain exceptions, an employer must pay severance to an employee where a labor contract is terminated or expires. In addition, the PRC governmental authorities have continued to introduce various new labor-related regulations since the effectiveness of the Labor Contract Law.

        Under the PRC Social Insurance Law and the Administrative Measures on Housing Fund, employees are required to participate in pension insurance, work-related injury insurance, medical insurance, unemployment insurance, maternity insurance, and housing funds and employers are required, together with their employees or separately, to pay the social insurance premiums and housing funds for their employees. If we fail to make adequate social insurance and housing fund contributions, we may be subject to fines and legal sanctions, and our business, financial conditions and results of operations may be adversely affected.

        These laws designed to enhance labor protection tend to increase our labor costs. In addition, as the interpretation and implementation of these regulations are still evolving, our employment practices may not be at all times be deemed in compliance with the regulations. As a result, we could be subject to penalties or incur significant liabilities in connection with labor disputes or investigations.

If we are found to be in violation of current or future PRC laws and regulations regarding Internet-related services and telecom-related activities, we could be subject to penalties or restrictions on our business activities.

        The PRC has enacted laws and regulations that apply to Internet-related services and telecom-related activities. While many aspects of these regulations remain unclear, they purport to require

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licenses on various aspects of the provision of Internet information and content, such as, for example, online video and music, online games, online publishing, and newsfeed services.

        Although we do not directly provide video and music content, our video and music link-aggregation services may be considered to be the provision of Internet audio-visual programs, which would require us to obtain an Internet audio-visual program transmission license. None of our VIEs currently holds such a license. In addition, current PRC laws and regulations require an applicant for an Internet audio-visual program transmission license to be a wholly state-owned or state-controlled entity unless the applicant had been operating a business involving transmission of Internet audio-visual programs prior to December 20, 2007. None of our VIEs currently is an eligible applicant for such a license, as none of them was operating Internet audio-visual services prior to December 20, 2007. If our video and music link-aggregation services were found to violate the applicable laws and regulations, we could be subject to fines, forced to remove all of the audio-visual links from our platform, and subject to a penalty equal to one to two times our total investment in the affected business. As of the date of this prospectus, we are in the process of negotiating to acquire an entity that holds a valid Internet audio-visual program transmission license. Such negotiation is at a preliminary stage, and there is no assurance that we will be able reach a deal on commercially reasonable terms in a timely manner, or at all.

        Current PRC laws and regulations require us to obtain an Internet publishing license for our online literature services and Sogou Ask. An Internet publishing license may also be required for our image search services and the distribution of online games through our Sogou Game Center, as these services may be considered to be "online publication services," which require an Internet publishing license under current PRC laws and regulations. None of our VIEs currently holds such a license. In addition, none of our VIEs currently holds an online news service license, which is required for our news search and newsfeed services. Operating without an Internet publishing license and an online news service license may subject us to various administrative sanctions, including fines and suspension of our relevant services. We are in the process of preparing an application for an Internet publishing license as of the date of this prospectus, and we expect to submit a complete application for such a license to the regulatory authorities in the fourth quarter of 2017. While PRC laws and regulations require relevant regulatory authorities to decide on an application for the Internet publishing license within 60 days after receiving a completed application, and we believe that we meet the qualifications for obtaining such a license, the approval process may take longer in practice, and we may not be able to receive approval for the license in a timely manner, or at all. As of the date of prospectus, we are also in the process of preparing applications for an online news search license. However, it appears that the competent authority may not currently be accepting new applications for online news search licenses, except applications for the renewal of licenses previously obtained. We plan to submit an application for an online news search license as soon as it becomes clear that the competent authority is accepting new applications. However, uncertainties remain as to when the relevant authority will begin to accept new applications for online news search licenses and, even after we have submitted an application if and when the authority begins to accept applications, there is no assurance that we will be granted the license in a timely manner, or at all.

        Although we are committed to complying with the above-described PRC laws and regulations applicable to Internet-related service and telecom-related activities, we cannot guarantee that we are now or will in the future be in full compliance with any such laws and regulations that apply to our services and activities. In the past, PRC regulatory authorities have imposed warnings and fines on us for conducting business without the aforementioned licenses. We cannot guarantee that PRC regulatory authorities will not impose similar or greater penalties on us in the future, which may include warnings, fines, mandates to remedy any violations, and/or cease providing all services and activities for which the licenses are required. The PRC government may also promulgate new laws and regulations that require additional licenses, permits and/or approvals for the operation of any of our existing and/or future

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businesses. If we are unable to obtain such licenses, permits, and/or approvals in a timely fashion, we could be subject to further penalties and operational disruption and our financial condition and results of operations could be adversely affected. For more details regarding PRC regulations, see "PRC Regulation."

The approval of the China Securities Regulatory Commission, or the CSRC, may be required in connection with our corporate structure and this offering, and the failure to obtain any required approval could have an adverse effect on our business and results of operations and the trading price of our ADSs, and also create uncertainties for this offering.

        In 2006, six PRC regulatory agencies, including the MOFCOM and the CSRC, jointly adopted the Rules on Mergers and Acquisitions of Domestic Enterprises by Foreign Investors, or the M&A Rules, which became effective on September 8, 2006 and were amended on June 22, 2009. See "PRC Regulation—Regulation of M&A and Overseas Listings." Under the M&A Rules, the prior approval of the CSRC is required for the overseas listing of offshore special purpose vehicles that are directly or indirectly controlled by PRC companies or individuals and used for the purpose of listing PRC onshore interests on an overseas stock exchange. The application of the M&A Rules remains unclear. Currently, there is no consensus among the leading PRC law firms regarding the scope and applicability of the CSRC approval requirement. Our PRC legal counsel, Commerce & Finance Law Offices, has advised us that based on its understanding of the current PRC laws, rules and regulations and the M&A Rules, prior approval from the CSRC is not required under the M&A Rules for the listing and trading of our ADSs because, among other reasons, (i) Sogou Technology and Sogou Network were incorporated as wholly foreign-owned enterprises by means of direct investment rather than by merger or acquisition of equity interest or assets of a PRC domestic company owned by PRC companies or individuals as defined under the M&A Rules that are the beneficial owners of the Company; and (ii) no provision in the M&A Rules clearly classifies contractual arrangements as a type of transaction subject to the M&A Rules. Although we have no plan to apply for approval from the CSRC based on the advice of our PRC legal counsel, we and our PRC legal counsel cannot assure you that the relevant PRC government agencies, including the MOFCOM and the CSRC, would not reach a different conclusion.

        Commerce & Finance Law Offices has further advised us that uncertainties still exist as to how the M&A Rules will be interpreted and implemented and its opinions summarized above are subject to any current or future laws, rules and regulations or detailed implementations and interpretations in any form relating to the M&A Rules. If the CSRC or other PRC regulatory agency subsequently determines that we need to obtain CSRC approval for this offering either by interpretation, clarification or amendment of the M&A Rules or by any new rules, regulations or directives promulgated after the date of this prospectus, we may face sanctions by the CSRC or other PRC regulatory agency. These sanctions may include fines and penalties on our operations in China, limitations on our operating privileges in China, delays or restrictions on the repatriation of the proceeds from this offering into the PRC, restrictions on or prohibition of the payment or remittance of dividends by our China-based subsidiaries, or other actions that could have an adverse effect on our business and results of operations, as well as this offering and the trading price of our ADSs. The CSRC or other PRC governmental authorities may also take actions requiring us, or making it advisable for us, to halt this offering before settlement and delivery of the ADSs offered hereby. Consequently, if you engage in market trading or other activities in anticipation of and prior to settlement and delivery, you do so at the risk that such settlement and delivery may not occur. We cannot predict when the CSRC will promulgate additional rules or other guidance. If additional rules or guidance is issued prior to the completion of this offering, and, consequently, we conclude that we are required to obtain the CSRC approval, this offering will be delayed until we obtain the CSRC approval, which may take several months or even longer. Moreover, additional rules or guidance, to the extent issued, may fail to resolve ambiguities under the M&A Rules. Uncertainties or negative publicity regarding the M&A Rules also could have an adverse effect the trading price of our ADSs.

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PRC laws and regulations mandate complex procedures for some acquisitions of Chinese companies by foreign investors, which could make it more difficult for us to make acquisitions in China.

        PRC laws and regulations, such as the M&A Rules, and other relevant rules, established additional procedures and requirements that are expected to make merger and acquisition activities in China by foreign investors more time-consuming and complex, including requirements in some instances that the MOFCOM be notified in advance of any change-of-control transaction in which a foreign investor takes control of a PRC domestic enterprise, or that the approval from the MOFCOM be obtained in circumstances where overseas companies established or controlled by PRC enterprises or residents acquire affiliated domestic companies. PRC laws and regulations also require certain merger and acquisition transactions to be subject to a merger control security review. In August 2011, the MOFCOM promulgated the Rules on Implementation of Security Review System, or MOFCOM Security Review Rules, effective from September 1, 2011, further provide that, when deciding whether a specific merger or acquisition of a domestic enterprise by foreign investors is subject to a security review by the MOFCOM, the principle of substance over form should be applied and foreign investors are prohibited from bypassing the security review requirement by structuring transactions through proxies, trusts, indirect investments, leases, loans, control through contractual arrangements of offshore transaction. Factors that the MOFCOM considers in its review are whether (i) an important industry is involved, (ii) such transaction involves factors that have had or may have an impact on national economic security and (iii) such transaction will lead to a change in control of a domestic enterprise that holds a well-known PRC trademark or a time-honored PRC brand. If a business of any target company that we plan to acquire falls into the ambit of security review, we may not be able to successfully acquire such company. Complying with the requirements of the relevant regulations to complete any such transaction could be time-consuming, and any required approval process, including approval from the MOFCOM, may delay or inhibit our ability to complete such transactions, which could affect our ability to expand our business.

        We entered into a series of transactions with Tencent in 2013 that resulted in Tencent being our largest shareholder and a Tencent group entity also holding a 45% interest in Sogou Information. If Tencent's investment in us ended due to competitive or regulatory reasons, our collaboration with Tencent may also be adversely affected.

The PRC government may prevent us from distributing, and we may be subject to liability for, content that it believes is inappropriate.

        The PRC has enacted regulations governing Internet access and the distribution of news and other information. In the past, the PRC government has stopped the distribution of information over the Internet that it believes to violate PRC laws, including content that is obscene, incites violence, endangers national security, is contrary to the national interest or is defamatory. In addition, we may not publish certain news items, such as news relating to national security, without permission from the PRC government. Furthermore, the Ministry of Public Security has the authority to make any local Internet service provider block any Website maintained outside the PRC at its sole discretion. Even if we comply with PRC governmental regulations relating to licensing and foreign investment prohibitions, if the PRC government were to take any action to limit or prohibit the distribution of information through our network or to limit or regulate any current or future content or services available to users on our network, our business would be harmed.

        We are also subject to potential liabilities for content delivered through our services that is deemed inappropriate and for any unlawful actions of users of our products and services under regulations promulgated by the MIIT, such potential liabilities including the imposition of fines or even the shutting down of the Internet platforms.

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        Furthermore, we are required to delete content that clearly violates PRC laws and report content that may violate PRC laws. We may have difficulty determining the type of content that may result in liability for us and, if we are wrong, we may be prevented from operating our Internet platforms.

Dividends we receive from our operating subsidiaries located in the PRC are subject to PRC profit appropriation and PRC withholding tax.

        PRC legal restrictions permit payment of dividends by our PRC subsidiaries only out of their accumulated profits, if any, determined in accordance with PRC accounting standards and regulations. Under PRC law, our PRC subsidiaries are also required to set aside 10% of their net income each year to fund certain reserve funds until these reserves equal 50% of the amount of registered capital. These reserves are not distributable as cash dividends.

        Furthermore, the PRC Corporate Income Tax Law, or the CIT Law, provides that a withholding tax at a rate of up to 10% may be applicable to dividends payable to non-PRC investors that are "non-resident enterprises," to the extent that such dividends are derived from sources within the PRC. Under the Arrangement Between the PRC and the Hong Kong Special Administrative Region on the Avoidance of Double Taxation and Prevention of Fiscal Evasion with Respect to Taxes on Income and Capital, or the China-HK Tax Arrangement, which became effective on January 1, 2007, the dividend withholding tax rate may be reduced to 5% if a Hong Kong resident enterprise is considered a non-PRC resident enterprise and holds at least 25% of the equity interests in the PRC enterprise distributing the dividends, subject to approval of the competent PRC tax authorities. However, if the Hong Kong resident enterprise is not considered to be the beneficial owner of such dividends under applicable PRC tax regulations, such dividends may remain subject to withholding tax at a rate of 10%. On October 27, 2009, the SAT issued a Notice on How to Understand and Determine the Beneficial Owners in Tax Agreement ("Circular 601"), which provides guidance on determining whether an enterprise is a "beneficial owner" under China's tax treaties and tax arrangements. Circular 601 provides that, in order to be a beneficial owner, an entity generally must be engaged in substantive business activities. A company that is set up for the purpose of avoiding or reducing taxes or transferring or accumulating profits will not be regarded as a beneficial owner and will not qualify for treaty benefits such as preferential dividend withholding tax rates. If any of our Hong Kong subsidiaries is, in the light of Circular 601, considered to be a non-beneficial owner for purpose of the China-HK Tax Arrangement, any dividends paid to it by any of our PRC Subsidiaries would not qualify for the preferential dividend withholding tax rate of 5%, but rather would be subject to the usual rate of 10%. All of our foreign-invested enterprises are subject to withholding tax, generally at a 10% rate.

Our offshore entities may need to rely on dividends and other distributions on equity paid by our PRC subsidiaries to fund any cash requirements those offshore entities may have. Our offshore entities may not be able to obtain cash from distributions because our subsidiaries and VIEs in China are subject to restrictions imposed by PRC law on paying such dividends and making other payments.

        Sogou Inc. is a holding company with no operating assets other than investments in Chinese operating entities through our intermediate holding companies, our subsidiaries in the Cayman Islands, and our VIEs. Our offshore entities may need to rely on dividends and other distributions on equity paid by our PRC subsidiaries for their cash requirements in excess of any cash raised from investors and retained by us or our other offshore entities. The primary source of any dividend payments to our offshore entities would need to be our PRC subsidiaries. It is possible that our PRC subsidiaries will not continue to receive payments in accordance with our VIE contracts with Sogou Information if such payments become subject to restrictions imposed by PRC laws. If our subsidiaries incur debt on their own behalf in the future, the instruments governing the debt may restrict their ability to pay dividends or make other distributions to us through the intermediate companies. In addition, dividends paid out of the PRC are generally subject to a withholding tax of 10%.

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        The PRC government also imposes controls on the convertibility of the RMB into foreign currencies and, in certain cases, the remittance of currencies out of the PRC. We may experience difficulties in completing the administrative procedures necessary to obtain and remit foreign currencies. If we or any of our subsidiaries are unable to receive the revenues from our operations through these service agreements and other arrangements, we may be unable to effectively fund any cash requirements we may have.

Regulation and censorship of information distribution in China may have an adverse effect on our business.

        China has enacted regulations governing Internet access and the distribution of news and other information. Furthermore, the Propaganda Department of the Chinese Communist Party takes the responsibility to censor news published in China to ensure, supervise, and control a particular political ideology. In addition, the MIIT has published implementing regulations that subject online information providers to potential liability for content included in websites and the actions of users of their systems, including liability for violation of PRC laws prohibiting the distribution of content deemed to be socially destabilizing. Furthermore, because many PRC laws, regulations, and legal requirements with regard to the Internet are relatively new and untested, their interpretation and enforcement may involve significant uncertainties. As a result, in many cases an Internet platform operator may have difficulty determining the type of content that may subject it to liability.

        Periodically, the Ministry of Public Security has stopped the distribution over the Internet of information which it believes to be socially destabilizing. Meanwhile, the Ministry of Public Security also has the authority to require any local Internet service provider to block any Website maintained outside China at its sole discretion. If the PRC government were to take action or exercise its authority to limit or eliminate our provision of access to information or to limit or regulate current or future applications available to our users, our business would be adversely affected.

        The State Secrecy Bureau, which is directly responsible for the protection of state secrets of all PRC government and Chinese Communist Party organizations, is authorized to block any Website it deems to be leaking state secrets or failing to meet the relevant regulations relating to the protection of state secrets in the distribution of online information. Under the applicable regulations, we may be held liable for any content transmitted by us. Furthermore, where the transmitted content clearly violates the PRC laws, we will be required to delete it. Moreover, if we consider transmitted content suspicious, we are required to report such content. We must also undergo computer security inspections, and if we fail to implement required safeguards against security breaches, we may be shut down. As the implementing rules of these new regulations have not been issued, we do not know how or when we will be expected to comply, or how our business will be affected by the application of these regulations.

We may be subject to the PRC government's ongoing crackdown on Internet pornographic content.

        The PRC government has stringent prohibitions on online pornographic information and has launched several crackdowns on Internet pornography recently. On December 4, 2009, the MIIT and other three PRC governmental authorities jointly issued the Incentives Measures for Report of Pornographic, Obscene and Vulgar Messages on Internet and Mobile Media, or the Anti-Pornography Notice, to further crack down on online pornography. Pursuant to this Anti-Pornography Notice, monetary rewards will be provided to Internet users who report websites that feature pornography. On April 13, 2014, the National Working Group on Anti-Pornography and three other PRC governmental authorities jointly issued the Anti-Pornography Proclamation, under which Internet service providers, including search companies such as us, must put in place software or other filters to prevent from appearing in search results, and immediately remove texts, images, video, advertisements, and other information that contain pornographic content. The relevant PRC governmental authorities may order

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enterprises or individuals who flagrantly produce or disseminate pornographic content to stop conducting business, and may revoke relevant administrative permits. It is possible that our users may engage in obscene conversations or activities on our platform that may be deemed illegal under PRC laws and regulations, and there is no assurance that content considered vulgar by PRC governmental authorities will not appear through our search services in the future. We may be subject to fines or other disciplinary actions, including in serious cases suspension or revocation of the licenses necessary to operate our platform, if we are deemed under PRC laws and regulations to have facilitated the accessing of inappropriate content through on our platform. In addition, if we are alleged by the government of providing access to vulgar content, our reputation could be adversely affected.

PRC regulations relating to offshore investment activities by PRC residents may limit our PRC subsidiaries' ability to increase their registered capital or distribute profits to us, limit our ability to inject capital into our PRC subsidiaries, or otherwise expose us to liability and penalties under PRC laws.

        In July 2014, SAFE promulgated Circular 37, which replaced Circular 75, promulgated by SAFE in October 2005 Circular 37 requires PRC residents, including PRC institutions and individuals, to register with the local SAFE office in connection with their direct establishment or indirect control of an offshore entity, referred to in Circular 37 as a "special purpose vehicle," for the purpose of holding domestic or offshore assets or interests. PRC residents must also file amendments to their registrations in the event of any significant changes with respect to the special purpose vehicle, such as increase or decrease of capital contributed by PRC individuals, share transfer or exchange, merger, division, or other material event. Under these regulations, PRC residents' failure to comply with specified registration procedures may result in restrictions being imposed on the foreign exchange activities of the relevant PRC entities, including the payment of dividends and other distributions to its offshore parent, as well as restrictions on capital inflows from the offshore entity to the PRC entities, including restrictions on the ability to contribute additional capital to the PRC entities.

        We have requested all of our current shareholders and/or beneficial owners to disclose whether they or their shareholders or beneficial owners fall within the scope of Circular 37 and other related rules, and requested such shareholders and beneficial owners, upon learning they are PRC residents, to make the necessary applications, filings and amendments as required under Circular 37 and other related rules prior to this offering. However, we may not be informed of the identities of all the PRC residents holding indirect interest in our company, and we cannot provide any assurances that these PRC residents will comply with our request to make or obtain any applicable registrations or comply with other requirements required by Circular 37 or related rules.

        Failure by any of our current or future shareholders or beneficial owners who are PRC residents to comply with the SAFE regulations may subject us to fines or other legal sanctions, or limit our ability to contribute additional capital to our PRC subsidiaries, or limit our PRC subsidiaries' ability to make distributions or pay dividends or affect our ownership structure, which could adversely affect our business and prospects. It is possible that some or all of our shareholders who are PRC residents will not comply with all the requirements required by Circular 37 or related rules. Any future failure by any of our shareholders who is a PRC resident, or controlled by a PRC resident, to comply with relevant requirements under these regulations could subject us to fines or legal sanctions imposed by the PRC government, including restrictions on our subsidiaries' ability to pay dividends or make distributions to us and our ability to increase our investment in these subsidiaries and restrict our cross-border investment activities, which could in turn limit our ability to distribute dividends to holders of our ordinary shares and ADSs.

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PRC regulatory requirements with respect to transfers by offshore holding companies, such as us, to their PRC subsidiaries and VIEs and governmental control of currency conversion may limit or delay our ability to transfer the net proceeds of this offering to our PRC subsidiaries and VIEs, which could have an adverse effect on our ability to fund and expand our business.

        As a holding company incorporated in the Cayman Islands, we will need to comply with applicable PRC laws and regulations in order to transfer the net proceeds of this offering to our PRC subsidiaries, Sogou Technology and Sogou Network, which are WFOEs under PRC law and are treated as FIEs, or to our VIEs in the PRC. We intend to contribute some or all of the net proceeds of this offering to our PRC subsidiaries, and to convert the contributed net proceeds into RMB. In order to make a capital contribution to either of our PRC subsidiaries, and convert the contributed amount from U.S. dollars into RMB, we will need to increase the PRC subsidiary's registered capital by registering and/or filing the increase with the MOFCOM or one of its local branches, the SAFE or one of its local branches, or an authorized bank. If we transfer any of the proceeds of this offering to one of our PRC subsidiaries or VIEs through loans, under current PRC law we will also need to register such loans with the SAFE or one its local branches, and the amount that we may convert into RMB and loan to one of these entities will be limited by applicable SAFE regulations, in the case of a loan to one of our PRC subsidiaries, to the greater of (i) the difference between the subsidiary's approved total investment and the subsidiary's total registered capital and (ii) two times the PRC subsidiary's net assets and, in the case of one of our VIEs, to two times the VIE's net assets.

        The need to comply with such requirements could prevent us from making timely transfers of the net proceeds of this offering to our PRC subsidiaries and, in the event we wish to make such transfers through loans to our PRC subsidiaries or VIEs, will limit the amounts of the net proceeds that we may transfer, which could limit our ability to fund or expand our business in accordance with our intended use of the proceeds of this offering. The amounts of total investment and registered capital of Sogou Technology as of June 30, 2017 were approximately US$100.0 million and US$40.0 million, and two times its net assets was equal to US$467.1 million, meaning that the limit on the proceeds of this offering that would be permitted to loan to Sogou Technology as of June 30, 2017 would be US$467.1 million. The amounts of total investment and registered capital of Sogou Network as of June 30, 2017 were both approximately US$0.8 million, and two times its net assets was equal to negative US$79.3 million, meaning that amount of the proceeds of this offering that we would be permitted to loan to Sogou Technology Network would be US$nil. Two times the net assets of our four VIEs was equal to US$69.5 million (Sogou Information), US$28.2 million (Chengdu Easypay), US$6.1 million (Shi Ji Si Su), and negative US$1.1 million (Shi Ji Guang Su), respectively, as of June 30, 2017, which represent the respective statutory limits on the amounts of loans we would be permitted to make to them as of June 30, 2017.

        On March 30, 2015, SAFE promulgated the Circular on Reforming Management of the Settlement of Foreign Exchange Capital of Foreign-Invested Enterprises, or Circular 19, which replaced previous regulations limiting a foreign-invested company's use of its RMB-settled registered capital. Although Circular 19 has lifted certain restrictions on the use by a foreign-invested enterprise of its RMB registered capital converted from foreign currencies, it continues to apply certain limits, including that such registered capital must be used only for purposes within the foreign-invested enterprise's approved business scope, and provides that violations of the regulations can result in severe penalties, including large fines. These regulations may limit our ability to transfer the net proceeds of this offering through contributions or loans to our PRC subsidiaries and VIEs to invest in or acquire other businesses or establish additional VIEs as it is unclear whether the SAFE would consider such uses to be within the respective scopes of business of our PRC subsidiaries and VIEs.

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We may be subject to fines and legal sanctions if we or our employees who are PRC citizens fail to comply with PRC regulations relating to employee share options.

        Under the Administration Measures on Individual Foreign Exchange Control issued by the PBOC and the related Implementation Rules issued the SAFE, all foreign exchange transactions by a PRC citizen involving an employee incentive plan of an overseas publicly-listed company may be conducted only with the approval of the SAFE. Under the Notice of Issues Related to the Foreign Exchange Administration for Domestic Individuals Participating in Stock Incentive Plan of Overseas Listed Company, or the Offshore Share Incentives Rules, issued by the SAFE on February 15, 2012, PRC citizens who are granted share options, restricted share units or restricted shares by an overseas publicly-listed company under such employee share incentive plans are required to register with the SAFE or its local offices and comply with a series of other requirements. The Offshore Share Incentives Rules also specify requirements for registration of share incentive plans, the opening and use of special accounts for the purpose of participation in incentive plans, and the remittance of funds for exercising options and gains realized from such exercises and sales of such options or the underlying shares, both outside and inside the PRC. We, and any of our PRC employees or members of our board of directors who have been granted share options or other share-based awards, are subject to the Administration Measures on Individual Foreign Exchange Control, the related Implementation Rules, and the Offshore Share Incentives Rules. In addition, pursuant to Circular 37, a privately-held special purpose vehicle's grant of equity incentives to a PRC citizen is subject to foreign exchange registration and, prior to making an investment in or receiving a grant of a share-based award in such an entity, a PRC citizen is required to apply with the relevant PRC governmental authorities for foreign exchange registration of the investment. We have not registered our 2010 Share Incentive Plan with the SAFE, and our PRC employees who have been granted share-based awards or held shares have not made the required registrations. After the completion of this offering, we will apply to have our 2010 Share Incentive Plan registered with the SAFE. However, if our 2010 Share Incentive Plan is not accepted for registration by the SAFE, we may not be able to grant share-based awards to our PRC employees, we and those who have received awards may be subject to fines and legal sanctions, and our ability to contribute additional capital to our PRC subsidiaries and our PRC subsidiaries' ability to distribute dividends to us may be limited.

If the status of certain of our PRC subsidiaries and VIEs as "High and New Technology Enterprises," "Key National Software Enterprises," or "Software Enterprises" is revoked or expires, we may have to pay additional taxes or make up any previously unpaid taxes and may be subject to a higher tax rate, which would adversely affect our results of operations.

        The CIT Law generally imposes a uniform income tax rate of 25% on all enterprises, but grants preferential treatment to "High and New Technology Enterprises," or HNTEs, pursuant to which HNTEs are instead subject to an income tax rate of 15%, subject to a requirement that they re-apply for HNTE status every three years. During this three-year period, an HNTE must conduct a qualification self-review each year to ensure it meets the HNTE criteria, and will be subject to the regular 25% income tax rate for any year in which it does not meet the criteria. The CIT Law and its implementing rules provide that a "Software Enterprise" is entitled to an income tax exemption for two years beginning with its first profitable year before December 31, 2017 and a 50% reduction to a rate of 12.5% for the subsequent three years. An entity that qualifies as a "Key National Software Enterprise," or KNSE, is entitled to a further reduced preferential income tax rate of 10%. Enterprises wishing to enjoy the status of Software Enterprises or KNSEs must perform a self-assessment each year to ensure they meet the relevant criteria for qualification. If at any time during the preferential tax treatment years an enterprise uses the preferential CIT rates but the relevant PRC governmental authorities determine that it failed to meet applicable criteria for qualification, the PRC governmental authorities may revoke the enterprise's Software Enterprise or KNSE status, as applicable.

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        There are uncertainties regarding future interpretation and implementation of the CIT Law and its implementing regulations. It is possible that the HNTE, Software Enterprise, and KNSE qualifications of our operating entities currently qualified as such, or their entitlement to an income tax exemption or refund of their value-added tax, or VAT, will be challenged by higher-level tax authorities and be repealed, or that there will be future implementing regulations that are inconsistent with current interpretation of the CIT Law. For example, in 2016 the SAT issued a circular with new criteria for certifying a Software Enterprise. Therefore, it is possible that the qualification of one or more of our PRC Subsidiaries or VIEs as a Software Enterprise will be challenged in the future or that such companies will not be able to take any further actions, such as re-application for Software Enterprise qualification, to enjoy such preferential tax treatment. If those operating entities cannot qualify for such preferential income tax status, our effective income tax rate will be increased significantly and we may have to pay additional income taxes to make up the previously unpaid taxes, which would reduce our net income.

We may be deemed a PRC resident enterprise under the CIT Law and be subject to PRC taxation on our worldwide income.

        The CIT Law provides that enterprises established outside of the PRC whose "de facto management bodies" are located within the PRC are considered "resident enterprises" and are generally subject to the uniform 25% enterprise income tax rate on their worldwide income (including dividend income received from subsidiaries). Under the Implementing Regulations for the Corporate Income Tax Law, "de facto management body" is defined as a body that has material and overall management and control over the manufacturing and business operations, personnel and human resources, finances and treasury, and acquisition and disposition of properties and other assets of an enterprise. Since substantially all of our operational management is currently based in the PRC, it is unclear whether PRC tax authorities would require us to be treated as a PRC-resident enterprise. If we are treated as a resident enterprise for PRC tax purposes, we will be subject to PRC taxes on our worldwide income at the 25% uniform tax rate, which could have an impact on our effective tax rate and an adverse effect on our net income and the results of operations, even though dividends distributed from our PRC Subsidiaries to us could be exempted from Chinese dividend withholding tax under the CIT Law for PRC-resident recipients.

Dividends paid by us to our foreign investors and profits on the sale of our shares or ADSs may be subject to tax under PRC tax laws.

        Under the Implementing Regulations for the Corporate Income Tax Law, PRC income tax at the rate of 10% is applicable to dividends paid to investors that are "non-resident enterprises," without an establishment or place of business in the PRC, or which do have such establishment or place of business but the relevant income is not effectively connected with the establishment or place of business, to the extent that such dividends have their sources within the PRC. In addition, any profits realized through the transfer of shares by such investors are subject to 10% PRC income tax if such profits are regarded as income derived from sources within the PRC. It is unclear whether dividends we pay with respect to our shares, or the profits you may realize from the transfer of our shares, would be treated as income derived from sources within the PRC and be subject to PRC taxes if we were treated as a PRC resident enterprise under the CIT Law. Non-resident individual investors may be liable for PRC income tax at a rate of 20% on dividend payments or in respect of profits on transfer of ADSs if such amounts are deemed to arise from sources within the PRC. In the case of dividend payments, we would be required to withhold the tax at source. Any PRC tax liability may be reduced under applicable tax treaties. If we are required under the Implementing Regulations for the Corporate Income Tax Law to withhold PRC income tax on dividends paid to our non-PRC investors that are "non-resident enterprises," or if you are required to pay PRC income tax on the transfer of our ADSs, the value of your investment in our ADSs may be adversely affected.

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Restrictions on currency exchange may limit our ability to use our revenues effectively.

        Substantially all of our revenues and operating expenses are denominated in RMB. The RMB is not freely tradable in "capital account" transactions, which include foreign direct investment. Foreign exchange transactions classified as capital account transactions are subject to limitations and require approval from the SAFE. This could affect our China-based subsidiaries' ability to obtain foreign exchange through debt or equity financing, including by means of loans or capital contributions from us.

        Further, the RMB is at present freely convertible in "current account" transactions, which include dividends, and trade and service-related foreign exchange transactions, and our China-based subsidiaries may purchase and retain foreign exchange for settlement of such transactions, including payment of dividends, without the approval of the SAFE. However, the relevant PRC governmental authorities may limit or eliminate our ability to purchase and retain foreign currencies in the future.

        Since a significant amount of our future revenues are likely to be in the form of RMB, these existing restrictions, and any future restrictions, on currency exchange may limit our ability to use revenues generated in RMB to fund our business activities outside of the PRC, or to make expenditures denominated in foreign currencies.

We may suffer currency exchange losses if the RMB depreciates relative to the U.S. dollar, which could reduce the value on an investment in our ADSs.

        Our reporting currency is the U.S. dollar. However, substantially all of our revenues are denominated in RMB. If the RMB depreciates relative to the U.S. dollar, our revenues and assets as expressed in our U.S. dollar financial statements will decline in value. In addition, to the extent that we need to convert U.S. dollars we receive from this offering into RMB for our operations, appreciation of the RMB against the U.S. dollar would have an adverse effect on the RMB amount we would receive from the conversion. Conversely, if we decide to convert our RMB into U.S. dollars for the purpose of paying dividends on our ordinary shares or for other business purposes, appreciation of the U.S. dollar against the RMB would have a negative effect on the U.S. dollar amount available to us.

Risks Related to Our Class A Ordinary Shares and ADSs

We are a Cayman Islands company and, because judicial precedent regarding the rights of shareholders is more limited under Cayman Islands law than that under U.S. law, our shareholders may have less protection for their shareholder rights than they would under U.S. law.

        Effective upon the completion of this offering, our corporate affairs will be governed by our Amended and Restated Memorandum of Association and Amended Restated Articles of Association and we are, and upon the completion of this offering will continue to be governed by the Companies Law of the Cayman Islands, and the common law of the Cayman Islands. The rights of shareholders to legal take action against our directors and us, actions by minority shareholders, and the fiduciary responsibilities of our directors to us under Cayman Islands law are to a large extent governed by the common law of the Cayman Islands. The common law of the Cayman Islands is derived in part from comparatively limited judicial precedent in the Cayman Islands as well as from English common law, which has persuasive, but not binding, authority on a court in the Cayman Islands. The rights of our shareholders and the fiduciary responsibilities of our directors under Cayman Islands law are not as clearly established as they would be under statutes or judicial precedent in some jurisdictions in the United States, such as the State of Delaware where many United States-based corporations are organized. In particular, the Cayman Islands has a less developed body of securities laws as compared to the United States, and provides significantly less protection to investors. In addition, shareholders of Cayman Islands companies may not have standing to initiate a shareholder derivative action in U.S. federal courts. As a result, our public shareholders may have more difficulty in protecting their

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interests through actions against us, our management, our directors, or our major shareholders than would shareholders of a corporation incorporated in a jurisdiction in the United States such as Delaware.

It may be difficult to enforce any civil judgments against us or our Board of Directors or officers, because most of our operating and/or fixed assets are located outside the United States.

        Although we are incorporated in the Cayman Islands, most of our operating and fixed assets are located in the PRC. As a result, it may be difficult for investors to enforce judgments outside the United States obtained in actions brought against us in the United States, including actions predicated upon the civil liability provisions of the federal securities laws of the United States or of the securities laws of any state of the United States. In addition, certain of our directors and officers (principally based in the PRC) and all or a substantial portion of their assets are located outside the United States. As a result, it may not be possible for investors to effect service of process within the United States upon those directors and officers, or to enforce against them or us judgments obtained in United States courts, including judgments predicated upon the civil liability provisions of the federal securities laws of the United States or of the securities laws of any state of the United States. We have been advised by our PRC legal counsel that, in their opinion, there are substantial uncertainties as to the enforceability in the PRC, in original actions or in actions for enforcement of judgments of United States courts, of civil liabilities predicated solely upon the federal securities laws of the United States or the securities laws of any state of the United States.

We have considerable discretion in the use of proceeds from this offering and we may use these proceeds in ways with which you may not agree.

        We intend to use the net proceeds from this offering for research and development, sales and marketing, and general corporate purposes, including potential strategic investments and acquisitions. We have not allocated the net proceeds of this offering to any particular project or acquisition. Rather, our board of directors and our management will have considerable discretion in the application of the net proceeds received by us. You will not have the opportunity, as part of your investment decision, to assess whether proceeds are being used appropriately. You must rely on the judgment of our board of directors and our management regarding the application of the net proceeds of this offering. The net proceeds may be used for corporate purposes that do not improve our efforts to maintain profitability or increase our ADS price. The net proceeds from this offering may be placed in investments that do not produce income or that lose value.

There has been no public market for our ordinary shares or ADSs prior to this offering, and you may not be able to resell our ADSs at or above the price you paid, or at all.

        Prior to this initial public offering, there has been no public market for our ordinary shares or ADSs. With the exception of the listing of our ADSs on the New York Stock Exchange, our ordinary shares and ADSs will not be listed or quoted for trading on any exchange. An active trading market for our ADSs may not develop after this offering, and if an active trading market for our ADSs does not develop, the market price of our ADSs may decline below the initial public offering price.

From time to time, press reports in the United States questioning the VIE structure used by us and various Chinese companies publicly traded in the United States may create concern among investors that may cause our ADS price to fluctuate.

        In recent years various prominent Western news outlets have questioned the use by Chinese companies that are publicly traded in the United States of VIE structure as a means of complying with PRC laws prohibiting or restricting foreign ownership of certain businesses in China, including businesses we are engaged in such as sponsored search, Internet information and content, online

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advertising, online game, and value-added telecommunication services. Some of such news reports have also sought to draw a connection between widely-reported accounting issues at certain Chinese companies and the use of VIE structure. Such news reports appear to have had the effect of causing concern among investors in several Chinese companies that are publicly traded in the United States. While we are not aware of any causal connection between the reported accounting scandals and the use of VIE structure, it is possible that investors in our ADSs will believe that such a connection exists. Any of such circumstances could lead to further loss of investor confidence in Chinese companies such as ours and cause fluctuations in the market prices of our ADSs and, if such prices were to drop sharply, could subject us to shareholder litigation, which could cause the price for our ADSs to drop further.

Registered public accounting firms in China, including our independent registered public accounting firm, are not inspected by the U.S. Public Company Accounting Oversight Board, which deprives us and our investors of the benefits of such inspection.

        Auditors of companies whose shares are registered with the U.S. Securities and Exchange Commission and traded publicly in the United States, including our independent registered public accounting firm, must be registered with the U.S. Public Company Accounting Oversight Board (the "PCAOB") and are required by the laws of the United States to undergo regular inspections by the PCAOB to assess their compliance with the laws of the United States and professional standards applicable to auditors. However, our independent registered public accounting firm is located in, and organized under PRC laws which is a jurisdiction where the PCAOB, notwithstanding the requirements of U.S. law, is currently unable to conduct inspections without the approval of the Chinese authorities.

        This lack of PCAOB inspections in China prevents the PCAOB from fully evaluating audits and quality control procedures of our independent registered public accounting firm. As a result, we and investors in our common stock are deprived of the benefits of such PCAOB inspections. The inability of the PCAOB to conduct inspections of auditors in China makes it more difficult to evaluate the effectiveness of our independent registered public accounting firm's audit procedures or quality control procedures as compared to auditors outside of China that are subject to PCAOB inspections, which could cause investors and potential investors in our stock to lose confidence in our audit procedures and reported financial information and the quality of our financial statements.

If additional remedial measures are imposed on the Big Four PRC-based accounting firms, including our independent registered public accounting firm, in administrative proceedings brought by the SEC alleging the firms' failure to meet specific criteria set by the SEC, we could be unable to timely file future financial statements in compliance with the requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act.

        In December 2012, the SEC instituted administrative proceedings against the Big Four PRC-based accounting firms, including our independent registered public accounting firm, alleging that these firms had violated U.S. securities laws and the SEC's rules and regulations thereunder by failing to provide to the SEC the firms' audit workpapers with respect to certain PRC-based companies that are publicly traded in the United States. On January 22, 2014, the administrative law judge presiding over the matter rendered an initial decision that each of the firms had violated the SEC's rules of practice by failing to produce audit workpapers to the SEC. The initial decision censured each of the firms and barred them from practicing before the SEC for a period of six months. On February 6, 2015, the four China-based accounting firms each agreed to a censure and to pay a fine to the SEC to settle the dispute and avoid suspension of their ability to practice before the SEC and audit U.S.-listed companies. The settlement required the firms to follow detailed procedures and to seek to provide the SEC with access to Chinese firms' audit documents via the CSRC. If future document productions fail to meet specified criteria, the SEC retains authority to impose a variety of additional remedial

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measures on the firms depending on the nature of the failure. While we cannot predict if the SEC will further review the four China-based accounting firms' compliance with specified criteria or if the results of such a review would result in the SEC imposing penalties such as suspensions or restarting the administrative proceedings, if the accounting firms are subject to additional remedial measures, our ability to file our financial statements in compliance with SEC requirements could be impacted. A determination that we have not timely filed financial statements in compliance with SEC requirements could ultimately lead to the delisting of our ADSs from the New York Stock Exchange or the termination of the registration of our ADSs and Class A ordinary shares under the Exchange Act, or both, which would substantially reduce or effectively terminate the trading of our ADSs in the United States.

If we fail to maintain an effective system of internal control over financial reporting, we may lose investor confidence in the reliability of our financial statements.

        We are subject to reporting obligations under the U.S. securities laws. The SEC, as required by Section 404 of the Sarbanes-Oxley Act of 2002, adopted rules requiring every public company to include a management report on the company's internal control over financial reporting in its annual report, which contains management's assessment of the effectiveness of our internal control over financial reporting. In addition, an independent registered public accounting firm must attest to and report on the effectiveness of our internal control over financial reporting.

        If we fail to maintain effective internal control over financial reporting in the future, our management and our independent registered public accounting firm may not be able to conclude that we have effective internal control over financial reporting at a reasonable assurance level. This could in turn result in loss of investor confidence in the reliability of our financial statements and negatively impact the trading price of our ADSs. Furthermore, we have incurred and anticipate that we will continue to incur considerable costs, management time and other resources in our efforts to comply with Section 404 and other requirements of the Sarbanes-Oxley Act.

We are a "controlled company" within the meaning of the New York Stock Exchange Listed Company Manual and as a result we are entitled to, and do, rely on exemptions from certain corporate governance requirements that provide protection to shareholders of other companies. We also have invoked one of the "home country practice" exceptions to the corporate governance requirements of the New York Stock Exchange Listed Company Manual that are available to foreign private issuers such as us, and we may invoke additional such exceptions in the future.

        Upon the completion of this offering, Sohu, through its ownership of Class B Ordinary Shares and the Voting Agreement with Tencent, will have the power to appoint a majority of our board of directors. As a result, we will be a "controlled company" under the New York Stock Exchange Listed Company Manual. We will rely on certain exemptions that are available to controlled companies from NYSE corporate governance requirements, including the following, which we do not intend to meet voluntarily:

•

that we have a majority of independent directors on our board;



•

that we have a compensation committee that is composed entirely of independent directors with a written charter addressing the committee's purpose and responsibilities; and



•

for an annual performance evaluation of the nominating/corporate governance committee and the compensation committee.

        We are not required to and will not voluntarily meet these requirements. If we are no longer a "controlled company," we may in the future invoke "home country" exceptions available to foreign private issuers, such as us, under the New York Stock Exchange Listed Company Manual which are

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similar to the exemptions for controlled companies, and also include the possibility of additional exceptions from the New York Stock Exchange Listed Company Manual, such as the requirement that equity-compensation plans be approved by shareholders. As a result of our use of the "controlled company" exemptions, and any future use by us of the "home country" exceptions, holders of our ADSs will not have the same protection afforded to shareholders of companies that are subject to all of NYSE corporate governance requirements.

Upon the completion of this offering, Sohu, through its ownership of Class B Ordinary Shares and a voting agreement with Tencent, will have the power to appoint a majority of our board of directors and Sohu and Tencent together will have the voting power to control the outcome of shareholder actions in our company.

        Our ordinary shares are divided into Class A Ordinary Shares and Class B Ordinary Shares. Holders of Class A Ordinary Shares are entitled to one vote per share, while holders of Class B Ordinary Shares are entitled to 10 votes per share. We will issue Class A ordinary shares represented by our ADSs in this offering, and Sohu and Tencent will each hold Class B Ordinary Shares. Upon the completion of this offering, Sohu, through its ownership of Class B Ordinary Shares and a voting agreement with Tencent, will continue have the power to appoint a majority of our board of directors. Sohu and Tencent together will have indirect shareholdings totaling approximately 72.1% of the total of our outstanding Class A and Class B Ordinary Shares and totaling approximately 96.2% of the total voting power of the combined total of our outstanding Class A and Class B ordinary shares, due to the additional voting power of the Class B Ordinary Shares. Sohu's and Tencent's combined voting power will give them the power to control actions that require shareholder approval under Cayman Islands law, our Amended and Restated Memorandum of Association and Amended and Restated Articles of Association, and the New York Stock Exchange Listed Company Manual, including significant mergers and acquisitions and other business combinations, changes to our Amended and Restated Memorandum of Association and Amended and Restated Articles of Association, the number of shares available for issuance under share incentive plans, and the issuance of significant amounts of our ordinary shares in private placements.

        Due to the disparate voting powers attached to the two classes of our ordinary shares, Sohu and Tencent will continue to have this power even if, at some point in the future, they hold considerably less than a majority of the combined total of our outstanding Class A and Class B ordinary shares.

        Sohu's and Tencent's voting control may cause transactions to occur that might not be beneficial to the holders of our ADSs, and may prevent transactions that would be beneficial to them. For example, Sohu's and Tencent's voting control may prevent a transaction involving a change of control of us, including transactions in which a holder of our ADSs might otherwise receive a premium for such securities over the then-current market price. In addition, Sohu and Tencent are not prohibited from selling their interests in us to a third party. Subject to certain limitations, if Sohu or Tencent is acquired or otherwise undergoes a change of control, or sells a controlling interest in us, any acquirer or successor will be entitled to exercise the voting control and contractual rights of Sohu or Tencent, as applicable, and may do so in a manner that could vary significantly from that of Sohu or Tencent.

We may have conflicts of interest with Sohu and Tencent, and such conflicts may not be resolved in our favor.

        Conflicts of interest may arise between Sohu and Tencent, on the one hand, and us, on the other hand, in a number of areas relating to our past and ongoing relationships. Potential conflicts of interest that we have identified include the following:

•

Employee recruiting and retention.   Because Sohu, Tencent, and we operate primarily in China and the main focus of the businesses of each of us is Internet services, we may compete with Sohu

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and Tencent in the hiring of new employees, in particular with respect to technology research and development. We have non-solicitation arrangements with Sohu and Tencent that would restrict either Sohu or Tencent, on the one hand, or us, on the other hand from hiring any of the other's employees.

•

Our board members and executive officers may have conflicts of interest.   Dr. Charles Zhang, who is our Chairman of the Board, is currently also serving as Sohu's chairman and chief executive officer. By virtue of the high-vote Class B Ordinary Shares held by Sohu and Tencent and the voting agreement between Sohu and Tencent, Sohu will have the power and right to appoint a majority of our Board of Directors and Tencent will have the right to appoint two of the member of our Board of Directors. These relationships could create, or appear to create, conflicts of interest when these persons are faced with decisions with potentially different implications for Sohu or Tencent and us.



•

Sale of shares in our company.   Although there are restrictions in the Voting Agreement among us, Sohu, and Tencent on transfers by Sohu or Tencent to competitors of ours, if the Voting Agreement were to terminate, Sohu or Tencent would no longer be subject to such transfer restrictions and may decide to sell all or a portion of our shares that it holds to one of our competitors, thereby giving that third party substantial influence over our business and our affairs. Such a sale could be contrary to the interests of certain of our shareholders, including our employees and holders of our ADSs.



•

Allocation of business opportunities.   Business opportunities may arise that both we and Sohu or Tencent find attractive, and which would complement our respective businesses. Sohu or Tencent may decide to take the opportunities itself, which would prevent us from taking advantage of the opportunity ourselves.



•

Developing business relationships with competitors of Sohu and Tencent.   For so long as Sohu retains the power to appoint a majority of our Board of Directors and Sohu and Tencent voting together retain the power to decide all other matters put to a vote of our shareholders, we may be limited in our ability to do business with the competitors of either of them, such as other providers of various Internet services in China. This may limit the our ability to enter into business relationships that might be in our best interests and those of our shareholders other than Sohu or Tencent.

        Although we are a stand-alone entity separate from Sohu and Tencent, we expect to operate, for as long as Sohu has the right to appoint a majority of our Board of Directors, as a part of the Sohu Group. Sohu may from time to time make strategic decisions that it believes are in the best interests of its business as a whole, including our company. These decisions may be different from the decisions that we would have made on our own. Sohu's decisions with respect to us or our business may be resolved in ways that favor Sohu and therefore Sohu's own shareholders, which may not coincide with the interests of shareholders other than Sohu. We may not be able to resolve any potential conflicts, and even if we do so, the resolution may be less favorable to us than if we were dealing with an unaffiliated shareholder. Even if both Sohu and we and Tencent seek to transact business on terms intended to approximate those that could have been achieved among unaffiliated parties, this may not succeed in practice.

The market price for our ADSs may be subject to fluctuations and our ADSs may trade below the initial public offering price.

        The initial public offering price of our ADSs will be determined by negotiations between us and the representative of the underwriters, based on numerous factors we discuss under "Underwriting." This price may not be indicative of the market price of our ADSs after this offering. You may not be able to resell your ADSs at or above the initial public offering price. The securities of a number of

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Chinese companies and companies with substantial operations in China have experienced price fluctuations subsequent to their initial public offerings. Among the factors that could affect the price of our ADSs are the various risk factors described in this prospectus and other factors, including:

•

announcements of competitive developments by our competitors;



•

regulatory developments in our target markets affecting us, our customers or our competitors;



•

actual or anticipated fluctuations in our operating results;



•

failure of our financial and operating results to meet market expectations or failure to meet our previously announced guidance;



•

changes in financial estimates by securities research analysts;



•

changes in the economic performance or market valuations of other Internet companies;



•

additions or departures of our executive officers and other key personnel;



•

announcements regarding litigation involving us or any of our directors and officers;



•

fluctuations in the exchange rates between the U.S. dollar and the RMB;



•

release or expiration of transfer restrictions on our outstanding ordinary shares and ADSs;



•

sales of our ordinary shares or ADSs in the market by Sohu or Tencent; and



•

sales or perceived sales of additional shares or ADSs.

        In addition, the securities markets have from time to time experienced significant price and volume fluctuations that are not related to the operating performance of particular industries or companies. Such market fluctuations may have an adverse effect on the market price of our ADSs.

Our dual-class ordinary share structure could have an adverse effect on the market price of our ADSs

        Our dual-class ordinary share structure, and the consequent concentration of voting power in Sohu and Tencent as a result of their ownership of our Class B Ordinary Shares, could adversely affect perceptions of us in the equity capital markets and could result in a lower market price for our ADSs. For example, apparently as a result of public criticism by commentators and shareholder advisory firms of companies with classes of shares with disparate voting rights, certain providers of indexes of publicly-traded equity shares, including FTSE Russell, S&P Dow Jones, and MSCI, have recently announced that they have either implemented, or are considering implementing, policies excluding companies with certain types of multiple-class voting structures from some of their published equity indexes. If our ADSs were to be excluded from such indexes, the market price of our ADSs could be adversely affected.

Holders of our ADSs may be subject to limitations on transfer of their ADSs.

        While following this offering our ADSs will be transferable on the books of the depositary, the depositary may close its transfer books at any time or from time to time when it deems it expedient in connection with the performance of its duties. In addition, the depositary may refuse to deliver, transfer or register transfers of ADSs generally when our books or the books of the depositary are closed, or at any time if we or the depositary deem it advisable to do so because of any requirement of law or of any government or governmental body, or under any provision of the Deposit Agreement, or for any other reason.

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Holders of ADSs have limited voting rights and may not receive voting materials in time to be able to exercise their right to vote.

        Except as described in this prospectus and in the Deposit Agreement, holders of our ADSs will not be able to exercise voting rights attaching to the shares represented by our ADSs on an individual basis. Holders of our ADSs may instruct the depositary how to exercise the voting rights attaching to the shares represented by the ADSs. You may not receive voting materials in time to instruct the depositary to vote, however, and it is possible that direct holders of ADSs, or persons who hold their ADSs through brokers, dealers or other third parties, will not have the opportunity to exercise a vote. In addition, due to the different voting powers attached to the two classes of our ordinary shares and a voting agreement between Sohu and Tencent, Sohu, our controlling shareholder, has the right to appoint a majority of our Board of Directors, Tencent has the right to appoint two of our directors, and Sohu and Tencent together control all other matters put to a shareholder vote. As a result, as a holder of our ADSs you will have no ability to affect the outcome of any matter subject to shareholder vote.

ADS holders' right to participate in any future rights offerings may be limited, which may cause dilution to their holdings and ADS holders may not receive cash dividends if it is impractical to make them available to such holders.

        We may from time to time distribute rights to our shareholders, including rights to acquire our securities. However, we cannot make rights available to ADS holders in the United States unless we register the securities to which the rights relate under the Securities Act of 1933, or the Securities Act, or an exemption from registration requirements is available. Also, under the Deposit Agreement, the depositary bank will not make rights available to ADS holders unless the distribution to ADS holders of both the rights and any related securities are either registered under the Securities Act or exempted from registration under the Securities Act. We are under no obligation to file a registration statement with respect to any such rights or securities or to endeavor to cause such a registration statement to be declared effective. Moreover, we may not be able to establish an exemption from registration under the Securities Act. Accordingly, holders of our ADSs may be unable to participate in our rights offerings and may experience dilution in their holdings.

        In addition, the depositary bank for our ADSs has agreed to pay to ADS holders the cash dividends or other distributions it or the custodian receives on our ordinary shares or other deposited securities after deducting its fees and expenses. ADS holders will receive these distributions in proportion to the number of ordinary shares such holders' ADSs represent. However, the depositary bank may, at its discretion, decide that it is inequitable or impractical to make a distribution available to any holders of ADSs. For example, the depositary may determine that it is not practicable to distribute certain property through the mail, or that the value of certain distributions may be less than the cost of mailing them, or that the distribution requires certain governmental approval, such as requirement for registration or approval for currency conversion. In these cases, the depositary may decide not to distribute that property and ADSs holders will not receive that distribution.

You will experience immediate and substantial dilution in the net tangible book value of ADSs purchased and will experience further dilution as outstanding share options are exercised.

        The initial public offering price per ADSs will be substantially higher than the net tangible book value per ADS prior to this offering. Consequently, when you purchase ADSs in the offering at an assumed initial public offering price of US$12.00, the mid-point of the estimated range of the initial public offering price, you will incur immediate dilution of US$10.21 per ADS. See "Dilution." In addition, you will experience further dilution to the extent that additional Class A Ordinary Shares are issued upon settlement outstanding share options or other share-based awards that we may grant from

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time to time. As of the date of this prospectus, there are options outstanding exercisable for the purchase of an aggregate of 4,337,754 Class A Ordinary Shares.

We may need additional capital and may sell additional ADSs or other equity securities or incur indebtedness, which could result in additional dilution to our shareholders or increase our debt service obligations.

        We may require additional cash resources due to changed business conditions or other future developments, including any investments or acquisitions we may decide to pursue. If our cash resources are insufficient to satisfy our cash requirements, we may seek to sell additional equity or debt securities or obtain a credit facility. The sale of additional equity securities or equity-linked debt securities could result in additional dilution to our shareholders. The incurrence of indebtedness would result in debt service obligations and could result in operating and financing covenants that would restrict our operations. We cannot assure you that financing will be available in amounts or on terms acceptable to us, if at all.

Substantial future sales of our ADSs or ordinary shares in the public market, or the perception that these sales could occur, could cause the price of our ADSs to decline.

        Additional sales of our ADSs or Class A ordinary shares in the public market after this offering, or the perception that these sales could occur, could cause the market price of our ADSs to decline. Upon completion of this offering, we will have 112,764,581 Class A ordinary shares and 278,757,875 Class B ordinary shares outstanding assuming the underwriters' overallotment option is not exercised. All ADSs sold in this offering, other than ADSs held by persons deemed to be our "affiliates," will be freely transferable without restriction under the Securities Act. The remaining ordinary shares outstanding after this offering will be available for sale upon the expiration of the 180-day lock-up period beginning from the date of this prospectus, subject to volume and other restrictions as applicable under Rule 144 under the Securities Act. Any of these shares may be released prior to the expiration of the lock-up period at the discretion of the lead underwriters for this offering. In addition, Sohu, Tencent, and Photon Group Limited, a British Virgin Islands company of which Dr. Charles Zhang, the Chairman of or Board of Directors may be deemed to be the beneficial owner, which will hold approximately 33.4%, 38.7%, and 8.2% of the combined total of our outstanding Class A and Class B Ordinary Shares upon completion of this offering, are parties to a registration rights agreement that gives them rights that, if exercised, will permit them to sell some or all of their shares freely in the open market after the expiration of the 180-day lock-up period beginning from the date of this prospectus without regard to the restrictions of Rule 144 under the Securities Act. As of the date of this prospectus, there are options outstanding exercisable for the purchase of an aggregate of 4,337,754 Class A Ordinary Shares. We also may grant or issue additional share options, restricted share units, or other share-based awards in the future under our share incentive plan to our management, employees and other persons, the settlement and sale of which may further dilute our shares and drive down the price of our ADSs.

We may be a passive foreign investment company, which could result in adverse U.S. federal income tax consequence to U.S. Holders of our ADSs or ordinary shares.

        If we are a passive foreign investment company, or PFIC, for any taxable year during which a U.S. holder, as defined under "Taxation—United States Federal Income Taxation—Passive Foreign Investment Company", held an ADS or a Class A ordinary share, certain adverse United States federal income tax consequences likely would apply to the U.S. holder. See "Taxation—United States Federal Income Taxation—Passive Foreign Investment Company."

        While we expect that we will not be a PFIC for U.S. federal income tax purposes for our current taxable year, our expectation is based on our current and anticipated operations and composition of our earnings and assets for the 2017 taxable year, including the current and expected valuation of our

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assets based on the expected price of our ADSs in this offering. However, we currently hold, and expect to continue to hold following the date of this prospectus, a substantial amount of cash, and the value of our other assets may be based in part on the market price of our ADSs, which is likely to fluctuate in the future (and may fluctuate considerably given that market prices of Internet companies historically have been especially volatile). Furthermore, it is not entirely clear how the contractual arrangements between us and our consolidated VIEs will be treated for purposes of the PFIC rules. In addition, our PFIC status for any taxable year cannot be determined until the close of such taxable year. Accordingly, there is no guarantee that we will not be a PFIC for any taxable year.

        U.S. holders and prospective holders of our ADSs are urged to consult their own tax advisors regarding the application of the PFIC rules to an investment in our ADSs or Class A ordinary shares.

We are an "emerging growth company," and any decision on our part to comply only with certain reduced reporting or disclosure requirements applicable to emerging growth companies could make our ADSs less attractive to investors.

        We are an "emerging growth company," as defined in the JOBS Act, and we may choose to take advantage of exemptions available to us under the JOBS Act from certain of the reporting or disclosure requirements that are otherwise applicable to public companies in the United States. It is possible that investors will find our ADSs less attractive if we choose to rely on these exemptions. If some investors find our ADSs less attractive as a result of any choices to reduce future disclosure, there may be a less active trading market for our ADSs and the market prices of our ADSs may be more volatile.

        As an emerging growth company under the JOBS Act, we have elected to opt out of the extended transition period for complying with new or revised accounting standards provided by JOBS Act. This election is irrevocable.

        We will remain as an emerging growth company until the earliest of (i) the end of our fiscal year in which our annual gross revenues exceed US$1,070,000,000; (ii) the end of our fiscal year in which the fifth anniversary of the completion of this offering occured; (iii) the date on which we have, during the previous three-year period, issued more than US$1.0 billion in non-convertible debt; or (iv) the date on which we qualify as a "large accelerated filer" under the Exchange Act, which may take place if the aggregate worldwide market value of our ordinary shares that are held by non-affiliates is at least US$700 million as of the last business day of our then most recently completed second fiscal quarter. If and after we cease to be an emerging growth company, we will not be entitled to the exemptions provided in the JOBS Act discussed above.

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Conventions that Apply to this Prospectus

        This prospectus also contains translations of Renminbi, or RMB, amounts into U.S. dollars for the convenience of the reader. Unless otherwise indicated, all translations from RMB to U.S. dollars in this prospectus were made at RMB6.6533 to US$1.00, the noon buying rate for September 29, 2017 set forth in the H.10 statistical release of the Board of Governors of the U.S. Federal Reserve Board. We make no representation that the RMB or U.S. dollar amounts referred to in this prospectus could have been or can be converted into U.S. dollars or RMB, as the case may be, at any particular rate or at all. See "Exchange Rate Information."

        As used in this prospectus:

•

"Amended and Restated Articles of Association" refers to our Third Amended and Restated Articles of Association, effective upon the completion of this offering;



•

"Amended and Restated Memorandum of Association" refers to our Seventh Amended and Restated Memorandum of Association, effective upon the completion of this offering;



•

"China" or the "PRC" refers to the People's Republic of China, and for the purpose of this prospectus, excludes Hong Kong, Macau, and Taiwan;



•

"Class A Ordinary Shares" refers to our Class A Ordinary Shares, par value of $0.001 per share, carrying one vote per share, that will be designated effective upon the completion of this offering;



•

"Class B Ordinary Shares" refers to our Class B Ordinary Shares, par value of $0.001 per share, carrying ten votes per share, that will be designated effective upon the completion of this offering;



•

"China Literature" refers to China Literature Limited, China's largest online literature platform;



•

"DAU," for those quoted from iResearch, for any given month, refers to the average number of active users per day during that month. A user who uses the applicable product more than once in any such day is counted as one active user for that day. Each distinguishable device or application is treated as a separate user for purposes of calculating such DAU;



•

"MAU," for those quoted from iResearch, for any given month, refers to the number of active users during that month. A user who uses the applicable product more than once in any such month is counted as one active user for that month. Each distinguishable device or application is treated as a separate user for purposes of calculating such MAU;



•

"Mobile DAU" for our Sogou Mobile Keyboard (the mobile application of Sogou Input Method), for any given month, refers to the average number of active users per day during that month. A user who uses Sogou Mobile Keyboard more than once in any such day is counted as one active user for that day. We treat each distinguishable device as a separate user for purposes of calculating such DAU, although it is possible that some people may use more than one device, and multiple people may share one device;



•

"Mobile MAU" for our Sogou Mobile Keyboard, for any given period, refers to the number of active users during the last month of such given period. A user who uses Sogou Mobile Keyboard more than once in that month is counted as one active user for that month. We treat each distinguishable device as a separate user for purposes of calculating such MAU, although it is possible that some people may use more than one device, and multiple people may share one device;



•

"Mobile MAU" for our Sogou mobile search, for any given period, refers to the number of active users during the last month of such given period. A user who uses Sogou mobile search

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more than once in that month is counted as one active user for that month. We treat each distinguishable mobile browser or each Sogou mobile search application as a separate user for purposes of calculating such MAU, although it is possible that on any given device, some people may use more than one mobile browser, and multiple people may share one mobile browser or one Sogou mobile search application;

•

"Paid clicks" refers to the number of paid clicks, including clicks by our users on advertisers' promotional links displayed on our search result pages and other Internet properties and third parties' Internet properties;



•

"PC DAU" for our Sogou Input Method, for any given month, refers to the average number of active users per day during that month. A user who uses Sogou Input Method more than once in any such day is counted as one active user for that day. We treat each distinguishable device as a separate user for purposes of calculating such DAU, although it is possible that some people may use more than one device, and multiple people may share one device;



•

"Pre-IPO Class A Ordinary Shares" refers to our Class A ordinary shares, carrying one vote per share, that were authorized and outstanding prior to the completion of this offering;



•

"Pre-IPO Class B Ordinary Shares" refers to our Class B ordinary shares, without voting rights, that were authorized and outstanding prior to the completion of this offering;



•

"Pre-IPO Ordinary Shares" refers to our Pre-IPO Class A Ordinary Shares and our Pre-IPO Class B Ordinary Shares;



•

"Pre-IPO Series A Preferred Shares" refers to our Series A preferred shares, carrying one vote per share, that were authorized and outstanding prior to the completion of this offering, and were categorized as "mezzanine equity" in our consolidated financial statements appearing elsewhere in this prospectus;



•

"Pre-IPO Series B Preferred Shares" refers to our Series B preferred shares, carrying one vote per share, that were authorized and outstanding prior to the completion of this offering, and were categorized as "mezzanine equity" in our consolidated financial statements appearing elsewhere in this prospectus;



•

"Pre-IPO Preferred Shares" refers to our Pre-IPO Series A Preferred Shares and our Pre-IPO Series B Preferred Shares, collectively;



•

"RMB" refers to Renminbi, or Yuan, the official currency of the PRC;



•

"Sogou" refers to Sogou Inc., a Cayman Islands company, and unless the context requires otherwise, includes its subsidiaries and variable interest entities, or VIEs;



•

"Sohu.com Inc." refers to our ultimate parent and controlling shareholder, whose shares of common stock are listed on the Nasdaq Global Select Market under the symbol "SOHU";



•

"Sohu" refers to Sohu.com Inc. and its subsidiaries and VIEs, not including Sogou and its subsidiaries and VIEs;



•

"Sohu Group" refers to Sohu.com Inc. and its subsidiaries and VIEs, including Sogou and its subsidiaries and VIEs;



•

"Tencent" or "Tencent group" refers to Tencent Holdings Limited and its subsidiaries under International Financial Reporting Standards;



•

"we," "us," "our company" and "our" refer to Sogou Inc., and unless the context requires otherwise, include its subsidiaries and VIEs;

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•

"Weixin Official Accounts" refers to Weixin/WeChat accounts where individuals and enterprises, as account owners, provide contents and services to subscribers; and



•

"Zhihu" refers to Zhihu Technology Limited and its affiliates, the leading online knowledge-sharing platform in China.

        Unless indicated otherwise, the information included in this prospectus assumes that the underwriters have not exercised their option to purchase additional ADSs to cover over-allotments and gives effect to the following, which will occur immediately prior to or upon the completion of this offering, as if they had occurred prior to the date of this prospectus:

•

Filing and effectiveness of our Amended and Restated Articles of Association and Amended and Restated Memorandum;



•

Redesignation of all of Pre-IPO Class A Ordinary Shares, other than Pre-IPO Ordinary Shares held by Sohu for its own account and by Tencent, into Class A Ordinary Shares;



•

Redesignation of all Pre-IPO Class A Ordinary Shares held by Sohu for its own account into Class B Ordinary Shares;



•

Redesignation of Pre-IPO Class A Ordinary Shares held by Tencent into Class B Ordinary Shares;



•

Redesignation of all Pre-IPO Class B Ordinary Shares, all of which were held by Tencent, into Class B Ordinary Shares;



•

Redesignation of all of Pre-IPO Series A Preferred Shares into Class A Ordinary Shares; and



•

Redesignation all of Pre-IPO Series B Preferred Shares, all of which were held by Tencent, into Class B Ordinary Shares.

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