Page 1

0 DE ( State or other jurisdiction of incorporation or organization ) 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 fiscal year ended December 31 , 2020 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-16189 801 East 86th Avenue Merrillville , IN ( Address of principal executive offices ) Securities registered pursuant to Section 12 ( b ) of the Act : NiSource Inc. ( Exact name of registrant as specified in its charter ) ( 877 ) 647-5990 ( Registrant's telephone number , including area code ) Title of Each Class Common Stock , par value $ 0.01 per share Depositary Shares , each representing a 1 / 1,000th ownership interest in a share of 6.50 % Series B Fixed - Rate Reset Cumulative Redeemable Perpetual Preferred Stock , par value $ 0.01 per share , liquidation preference $ 25,000 per share and a 1 / 1,000th ownership interest in a share of Series B - 1 Preferred Stock , par value $ 0.01 per share , liquidation preference $ 0.01 per share Trading Symbol ( s ) NI NI PR B 35-2108964 ( I.R.S. Employer Identification No. ) 46410 ( Zip Code ) Name of Each Exchange on Which Registered NYSE NYSE Securities registered pursuant to Section 12 ( g ) of the Act : None Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes þ No¨ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15 ( d ) of the Act . Yes " No p 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 p No Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( §232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes p No Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definition of “ large accelerated filer , ” “ accelerated filer , ” “ smaller reporting company , " and " emerging growth company " in Rule 12 - b - 2 of the Exchange Act . Large accelerated filer p Accelerated Filer " Emerging Growth Company Non - accelerated Filer " Smaller Reporting Company If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . □ Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404 ( b ) of the Sarbanes - Oxley Act ( 15 U.S.C. 7262 ( b ) ) by the registered public accounting firm that prepared or issued its audit report . Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes No þ The aggregate market value of the registrant's common stock , par value $ 0.01 per share ( the " Common Stock " ) held by non - affiliates was approximately $ 8,671,854,266 based upon the June 30 , 2020 , closing price of $ 22.74 on the New York Stock Exchange . There were 391,859,711 shares of Common Stock outstanding as of February 9 , 2021 .