Bylaw Amendment · Shareholder Vote

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 26, 2026 JEFFERIES FINANCIAL GROUP INC. (Exact name of registrant as specified in its charter) New York 001-05721 13-2615557 (State of other jurisdiction of incorporation or organization) (Commission File Number) (IRS. Employer Identification No.) 520 Madison Ave. , New York , New York   10022 (Address of principal executive offices)   (Zip Code) Registrant’s telephone number, including area code: 212 - 284-2300 Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions ( see General Instruction A.2, below): ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Exchange Act: Title of each class   Trading Symbol(s)   Name of each exchange on which registered           Common Stock, par value $1.00 per share   JEF   New York Stock Exchange 4.850% Senior Notes Due 2027   JEF 27A   New York Stock Exchange 5.875% Senior Notes Due 2028   JEF 28   New York Stock Exchange 2.750% Senior Notes Due 2032   JEF 32A   New York Stock Exchange 6.200% Senior Notes Due 2034   JEF 34   New York Stock Exchange 5.500% Senior Notes Due 2036   JEF 36   New York Stock Exchange Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). 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. ☐ Item 5.03 Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year On March 26, 2026, Jefferies Financial Group Inc. (the “ Company ”, “ we ” or “ our ”) held its Annual Meeting of Shareholders (the “ Annual Meeting ”), at which the Company’s shareholders approved an amendment and restatement of the Certificate of Incorporation of the Company (the “ Restated Certificate of Incorporation ”) to increase the number of authorized shares of the existing class of non-voting common stock, par value $1.00 per share.  On March 27, 2026, the Company delivered the Restated Certificate of Incorporation to the Department of State of the State of New York for filing.  The description of the amendment and restatement effected by the Restated Certificate of Incorporation is incorporated herein by reference to the text of the section titled “ Proposal 4: Amendment and Restatement of the Certificate of Incorporation ” of the Company’s definitive proxy statement filed with the Securities and Exchange Commission on February 23, 2026.  Such description is qualified in its entirety by the full text of the Restated Certificate of Incorporation, which has been filed as Exhibit 3.1 to this Current Report on Form 8-K and is incorporated by reference herein. The Restated Certificate of Incorporation was effective as of the filing with the Department of State of the State of New York on March 27, 2026. Item 5.07 Submission of Matters to a Vote of Security Holders Set forth below are the final voting results for each of the matters submitted to a vote of the shareholders at the Annual Meeting. Our director nominees were elected to our Board of Directors and received the following votes:     Number of Shares           For   Against   Abstain   Broker Non-Votes   Linda L. Adamany     149,862,077     12,148,486     476,831     19,736,294   Robert D. Beyer     154,115,324     7,878,466     493,604     19,736,294   Matrice Ellis Kirk     158,388,284     3,586,069     513,041     19,736,294   Brian P. Friedman     160,822,258     1,406,374     258,762     19,736,294   MaryAnne Gilmartin     155,034,068     6,939,810     513,516     19,736,294   Richard B. Handler     160,877,951     1,348,999     260,444     19,736,294   Yoshihiro Hyakutome     160,943,629     1,162,789     380,976     19,736,294   Thomas W. Jones     159,661,357     2,299,873     526,164     19,736,294   Jacob M. Katz     159,628,315     2,369,202     489,877     19,736,294   Michael T. O’Kane     153,460,758     8,533,751     492,885     19,736,294   Joseph S. Steinberg     158,549,326     3,626,220     311,848     19,736,294   Melissa V. Weiler     154,333,178     7,676,007     478,209     19,736,294   Our shareholders approved, on a non-binding advisory basis, our executive-compensation program.  Voting results were as follows:     Number of Shares   For     142,257,066   Against     19,633,316   Abstain     597,012   Broker Non-Votes     19,736,294   Our shareholders ratified the selection of Deloitte & Touche LLP as our independent auditors for the fiscal year ending November 30, 2026.  Voting results were as follows:     Number of Shares   For     181,007,063   Against     844,926   Abstain     371,699   Our shareholders approved the Restated Certificate of Incorporation to increase the number of authorized shares of the existing class of non-voting common stock, par value $1.00 per share.  Voting results were as follows:     Number of Shares For   181,470,620 Against   471,274 Abstain   281,794 In connection with the Annual Meeting, we also solicited proxies with respect to the adjournment of the Annual Meeting for the purpose of soliciting additional proxies if there were insufficient votes at the Annual Meeting to approve the Restated Certificate of Incorporation (the “ Adjournment Proposal ”).  As there were sufficient votes at the time of the Annual Meeting to approve the Restated Certificate of Incorporation, the Adjournment Proposal was unnecessary and such proposal was not submitted to the shareholders for approval at the Annual Meeting. Item 9.01 Financial Statements and Exhibits (d) Exhibits   Exhibit Number Description         3.1 Restated Certificate of Incorporation of Jefferies Financial Group Inc.         104 Cover Page Interactive Data File (embedded within the Inline XBRL document) SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Date: March 31, 2026 JEFFERIES FINANCIAL GROUP INC.       /s/ Michael J. Sharp   Michael J. Sharp   Executive Vice President and General Counsel