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Table of Contents 冈 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON , D.C. 20549 ( Mark One ) Annual Report Pursuant to Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 For the fiscal year ended May 31 , 2021 or ■ FORM 10 - K Transition Report Pursuant to Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 For the transition period from Title of Each Class Common Stock , $ 1.00 par value Commission file number 1-6263 Delaware ( State or other jurisdiction of incorporation or organization ) to AAR CORP . ( Exact name of registrant as specified in its charter ) 36-2334820 ( I.R.S. Employer Identification No. ) One AAR Place , 1100 N. Wood Dale Road , Wood Dale , Illinois 60191 ( Address of principal executive offices , including zip code ) Registrant's telephone number , including area code : ( 630 ) 227-2000 Securities registered pursuant to Section 12 ( b ) of the Act : Trading Symbol ( s ) AIR Accelerated filer ☐ Non - accelerated filer Name of Each Exchange on Which Registered New York Stock Exchange Chicago Stock Exchange 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 Rule 405 of the Securities Act . Yes 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 = 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 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 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 definitions of " large accelerated filer , " " accelerated filer , " " smaller reporting company , " and " emerging growth company " in Rule 12b - 2 of the Exchange Act . Large accelerated filer Smaller reporting company Emerging growth 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 Exchange Act ) . Yes No The aggregate market value of the registrant's voting stock held by nonaffiliates was approximately $ 952 million ( based upon the closing price of the Common Stock at November 30 , 2020 as reported on the New York Stock Exchange ) . On June 30 , 2021 , there were 35,404,605 shares of Common Stock outstanding . Documents Incorporated by Reference Portions of the Company's proxy statement for the Company's 2021 Annual Meeting of Stockholders , to be held September 28 , 2021 , are incorporated by reference in Part III of this report .