Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 20-F REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR _ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2017 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of event requiring this shell company report . For the transition period from to Commission file number: 001-37361 SINA CORPORATION (Exact name of Registrant as specified in its charter) Cayman Islands (Jurisdiction of incorporation or organization) No. 8 SINA Plaza, Courtyard 10, the West Xibeiwang E. Road, Haidian District Beijing 100193, People’s Republic of China (Address of principal executive offices) Bonnie Yi Zhang, Chief Financial Officer Phone: +86 10 8262 8888 Facsimile: +86 10 8260 7166 7/F SINA Plaza, No. 8 Courtyard 10 West Xibeiwang E. Road, Haidian District, Beijing 100193, People’s Republic of China (Name, Telephone, E-mail and/or Facsimile number and Address of Company Contact Person) Securities registered or to be registered pursuant to Section 12(b) of the Act. Title of each class Name of each exchange on which registered Ordinary Shares, $0.133 par value The Nasdaq Stock Market LLC Ordinary Shares Purchase Rights (Nasdaq Global Select Market) Securities registered or to be registered pursuant to Section 12(g) of the Act. Not Applicable (Title of Class) Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act. Not Applicable (Title of Class) As of December 31, 2017, there were 71,409,729 ordinary shares of the registrant outstanding (excluding 10,079,948 ordinary shares that have been repurchased but not cancelled), par value $0.133 per share, and 7,150 class A preference shares of the registrant outstanding, par value $1.00 per share. Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. _ Yes No If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. Yes _ No Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. _ Yes No Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§229.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). _ Yes No Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or an emerging growth company. See the definitions of “large accelerated filer,”, “accelerated filer” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one): Large accelerated filer _ Accelerated filer Non-accelerated filer Emerging growth company (Do not check if a smaller reporting company) If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards† provided pursuant to Section 13(a) of the Exchange Act. † The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012. Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing: U.S. GAAP _ International Financial Reporting Standards as issued Other by the International Accounting Standards Board If “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrant has elected to follow. Item 17 Item 18 If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes _ No (APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY PROCEEDINGS DURING THE PAST FIVE YEARS) Indicate by check mark whether the registrant has filed all documents and reports required to be filed by Sections 12, 13 or 15(d) of the Securities Exchange Act of 1934 subsequent to the distribution of securities under a plan confirmed by a court. Yes No Table of Contents TABLE OF CONTENT INTRODUCTION 1 INFORMATION REGARDING FORWARD-LOOKING STATEMENTS 2 PART I 3 ITEM 1. IDENTITY OF DIRECTORS, SENIOR MANAGEMENT AND ADVISERS 3 ITEM 2. OFFER STATISTICS AND EXPECTED TIMETABLE 3 ITEM 3. KEY INFORMATION 3 ITEM 4. INFORMATION ON THE COMPANY 40 ITEM 4A. UNRESOLVED STAFF COMMENTS 72 ITEM 5. OPERATING AND FINANCIAL REVIEW AND PROSPECTS 72 ITEM 6. DIRECTORS, SENIOR MANAGEMENT AND EMPLOYEES 95 ITEM 7. MAJOR SHAREHOLDERS AND RELATED PARTY TRANSACTIONS 106 ITEM 8. FINANCIAL INFORMATION 113 ITEM 9. THE OFFER AND LISTING 114 ITEM 10. ADDITIONAL INFORMATION 115 ITEM 11. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK 124 ITEM 12. DESCRIPTION OF SECURITIES OTHER THAN EQUITY SECURITIES 125 PART II 126 ITEM 13. DEFAULTS, DIVIDEND ARREARAGES AND DELINQUENCIES 126 ITEM 14. MATERIAL MODIFICATIONS TO THE RIGHTS OF SECURITY HOLDERS AND USE OF PROCEEDS 126 ITEM 15. CONTROLS AND PROCEDURES 126 ITEM 16A. AUDIT COMMITTEE FINANCIAL EXPERT 126 ITEM 16B. CODE OF ETHICS 127 ITEM 16C. PRINCIPAL ACCOUNTANT FEES AND SERVICES 127 ITEM 16D. EXEMPTIONS FROM THE LISTING STANDARDS FOR AUDIT COMMITTEES 127 ITEM 16E. PURCHASES OF EQUITY SECURITIES BY THE ISSUER AND AFFILIATED PURCHASERS 127 ITEM 16F. CHANGE IN REGISTRANT’S CERTIFYING ACCOUNTANT 128 ITEM 16G. CORPORATE GOVERNANCE 128 ITEM 16H. MINE SAFETY DISCLOSURE 128 PART III 129 ITEM 17. FINANCIAL STATEMENTS 129 ITEM 18. FINANCIAL STATEMENTS 129 ITEM 19. EXHIBITS 129 i Table of Contents INTRODUCTION In this annual report, except where the context otherwise requires and for purposes of this annual report only: x “we,” “us,” “our company,” “the Company,” “our” and “SINA” refer to Sina Corporation, its subsidiaries, and, in the context of describing our operations and consolidated financial information, include our consolidated variable interest entities (“VIEs”) in China; x “China” or “PRC” refers to the People’s Republic of China and, solely for the purpose of this annual report, do not include the Hong Kong Special Administrative Region, the Macau Special Administrative Region or Taiwan; x “GAAP” refers to generally accepted accounting principles in the United States; x “monthly active users” or “MAUs” refer to monthly active users, which are Weibo users who logged in and accessed Weibo through Weibo’s website, mobile website, desktop or mobile applications, SMS or connections via platform partners’ websites or applications that are integrated with Weibo, during a given calendar month. The numbers of MAUs are calculated using internal company data that has not been independently verified, and we treat each account as a separate user for purposes of calculating MAUs, although it is possible that certain individuals or organizations may have set up more than one account and certain accounts are used by multiple individuals within an organization; x “daily active users” or “DAUs” refer to daily active users, which are Weibo users who logged in and accessed Weibo through Weibo’s website, mobile website, desktop or mobile applications, SMS or connections via platform partners’ websites or applications that are integrated with Weibo, on a given day, and “average DAUs” for a month refers to the average of the DAUs for each day during the month. The numbers of DAUs are calculated using internal company data that has not been independently verified, and we treat each account as a separate user for purposes of calculating DAUs, although it is possible that certain individuals or organizations may have set up more than one account and certain accounts are used by multiple individuals within an organization; x “shares” refer to our ordinary shares; x all references to “RMB” or “renminbi” are to the legal currency of China, and all references to “$,” “dollars,” “US$” and “U.S. dollars” are to the legal currency of the United States. Unless otherwise noted, all translations from RMB to U.S. dollars and from U.S. dollars to RMB in this annual report were made at a rate of RMB6.5063 to US$1.00, the exchange rate on December 29, 2017 as set forth in the H.10 statistical release published by the Federal Reserve Board; and x all discrepancies in any table between the amounts identified as total amounts and the sum of the amounts listed therein are due to rounding. 1 Table of Contents INFORMATION REGARDING FORWARD-LOOKING STATEMENTS This Annual Report on Form 20-F contains forward-looking statements. These statements relate to future events or our future financial performance. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “potential” or “continue,” and the negative of such terms or other comparable terminology.