Jefferies Financial Group Inc. 美股招股说明书（2026年5月8日版）

(to Product Supplement no. 5, dated October 23, 2023,Prospectus Supplement dated May 12, 2023and Prospectus dated May 12, 2023) Jefferies Jefferies Financial Group Inc. Senior Autocallable Contingent Coupon Barrier Notes due May 18, 2028Linked to the Worst-Performing of the iShares®MSCI EAFE®ETF, the Russell 2000®Index and the S&P 500®Index The Senior Autocallable Contingent Coupon Barrier Notes due May 18, 2028 Linked to the Worst-Performing of the iShares®MSCI EAFE®ETF, the Russell 2000®Index and the S&P 500®Index (the “Notes”) are senior unsecured obligations of Jefferies Financial Group Inc. The Notes have the terms described in the accompanying product supplement, prospectus supplement Aggregate Principal Amount:Issue Price:Stated Principal Amount:Pricing Date:Original Issue Date:Coupon Observation Dates: Coupon Payment Dates: Call Observation Dates: Quarterly, beginning on November 16, 2026, as set forth on page PS-2. The Call Observation Dates are subject to postponement as described inthe accompanying product supplement.As set forth on page PS-2. The Call Payment Dates may be postponed if the related Call Observation Date is postponed as described in theaccompanying product supplement.May 15, 2028, subject to postponement as described in the accompanying product supplement. Call Payment Dates: Valuation Date:Maturity Date:Underlying: May 18, 2028, which may be postponed if the Valuation Date is postponed as described in the accompanying product supplement.The worst-performing of the iShares®MSCI EAFE®ETF (the “EFA”), the Russell 2000®Index (the “RTY”) and the S&P 500®Index (the “SPX”).Please see “The Underlyings” below. Worst-Performing Underlying:Coupon Feature: Contingent Coupon Payments. The Notes will pay a Contingent Coupon Payment of $30 on the applicable Coupon Payment Date if theObservation Value of the Worst-Performing Underlying on the applicable quarterly Coupon Observation Date is greater than or equal to its CouponBarrier. Call Feature: Autocallable Notes. The Notes will be automatically called if the Observation Value of the Worst-Performing Underlying on any Call ObservationDate (beginning approximately six months after the Pricing Date) is equal to or greater than its Call Value. If your Notes are called, you will receivethe Call Payment on the applicable Call Payment Date, and no further amounts will be payable on the Notes. If the Final Value of the Worst-Performing Underlying is greater than or equal to its Threshold Value, you will receive for each Note that youhold a Payment at Maturity that is equal to the Stated Principal Amount If the Final Value of the Worst-Performing Underlying is less than its Threshold Value, you will receive for each Note that you hold a In this scenario the Payment at Maturity will be less than the Stated Principal Amount and you could lose some or all of your investment.The Payment at Maturity will also include the final Contingent Coupon Payment if the Observation Value of the Worst-Performing Underlying on thefinal Coupon Observation Date is greater than or equal to its Coupon Barrier. With respect to theEFA, the ETF Closing Price of the Underlying on the Pricing Date. Initial Value: Observation Value: Final Value: With respect to theEFA, the ETF Closing Price of the Underlyingtimesthe Adjustment Factor on the Valuation Date.With respect to each of theRTY and the SPX, the Index Closing Value of the Underlying on the Valuation Date. Coupon Barrier:Call Value:Threshold Value:Adjustment Factor: Specified Currency:CUSIP/ISIN:Book-entry or Certificated Note:Business Day:Agent:Calculation Agent:Trustee:Estimated value on the Pricing Date:Approximately $977.70 per Note, or within $30.00 of that estimate. Please see “The Notes” below.Use of Proceeds:Listing:Conflict of Interest: Jefferies LLC, the broker-dealer subsidiary of Jefferies Financial Group Inc., is a member of FINRA and will participate in the distribution of thenotes being offered hereby. Accordingly, the offering is subject to the provisions of FINRA Rule 5121 relating to conflicts of interest and will beconducted in accordance with the requirements of Rule 5121. See “Conflict of Interest.” Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this pricing supplement or theaccompanying product supplement, prospectus or prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.As used in this pricing supplement, “we,” “us” and “our” refer to Jefferies Financial Group Inc., unless the context requires otherwise. We will deliver the Notes in book-entry form only through The Depository Trust Company on or about May 20, 2026 against payment in immediately available funds. Pricing supplement dated,2026.You should read this pricing supplement together with the related product supplement, prospectus and prospectus supplement, each of wh