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Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 FORM 10 - K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the year ended December 31 , 2020 Commission File Number : 001-33440 INTERACTIVE BROKERS GROUP , INC . ( Exact name of registrant as specified in its charter ) Delaware ( State or other jurisdiction of incorporation or organization ) Securities registered pursuant to Section 12 ( b ) of the Act : Title of each class Common Stock , par value $ .01 per share One Pickwick Plaza Greenwich , Connecticut 06830 ( Address of principal executive office ) ( 203 ) 618-5800 ( Registrant's telephone number , including area code ) Trading Symbol IBKR Accelerated filer o 30-0390693 ( I.R.S. Employer Identification No. ) Securities registered pursuant to Section 12 ( g ) of the Act : None Indicate by check mark whether the registrant is a well - known seasoned issuer , as defined in Rule 405 of the securities act . Yes x No o Indicate by check mark whether the registrant is not required to file reports pursuant to Section 13 or 15 ( d ) of the act . Yes o Nox 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 x No o Name of the exchange on which registered The Nasdaq Global Select Market Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T during the preceding 12 months ( or for such shorter period that the registrant was required to submit and post such files ) . Yes x No o Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , " " accelerated filer " , " smaller reporting company ” and “ emerging growth company " in Rule 12b - 2 of the Exchange Act . ( Check one ) : Large accelerated filer x Non - accelerated filer o Smaller reporting company o Emerging growth company o If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . o Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404 ( b ) of the Sarbanes - Oxley Act ( 15 U.S.C. 7262 ( b ) ) by the registered public accounting firm that prepared or issued its audit report . Yes x No o Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Exchange Act ) . Yes o No x The aggregate market value of the voting and non - voting common equity stock held by non - affiliates of the registrant was approximately $ 3,155,276,668 computed by reference to the $ 41.77 closing sale price of the common stock on the Nasdaq Global Select Market , on June 30 , 2020 , the last business day of the registrant's most recently completed second fiscal quarter . As of February 25 , 2021 , there were 90,780,441 shares of the issuer's Class A common stock , par value $ 0.01 per share , outstanding and 100 shares of the issuer's Class B common stock , par value $ 0.01 per share , outstanding . Documents Incorporated by Reference : Portions of Registrant's definitive proxy statement for its 2021 annual meeting of shareholders are incorporated by reference in Part III of this Form 10 - K .