STEEL DYNAMICS INC (STLD) · Insider Trading (Form 4) SEC Filing

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-06-01 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: STEEL DYNAMICS INC (STLD) CIK: 0001022671 --- Reporting Owner --- Name: Seaman Bradley S CIK: 0001597069 Role: Director --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock Date: 2026-06-01 | Code: A (Grant or award) Shares: +712 | Price: $0.00 Shares Owned After: 51,491 | Ownership: D (Direct) Footnotes: [F1] Issued as deferred stock units (DSUs) in connection with reporting person's retainer as a director under the Company's 2023 Equity Incentive Plan and exempt from Section 16(b) by virtue of Rule 16b-3(d)(1) and (3). These DSUs are reportable, however, as directly owned shares of common stock, rather than as a derivative security in Table II, because any and all underlying DSUs are payable, at such time as they are to be settled, solely in common stock. See Lincoln National Corp. (March 20, 1992) (Q.3). The DSUs vest as follows: 1/4 on 8/31/2026, 1/4 on 11/30/2026, 1/4 on 2/28/2027 and 1/4 on 5/31/2027. --- Footnotes (Complete Index) --- F1: Issued as deferred stock units (DSUs) in connection with reporting person's retainer as a director under the Company's 2023 Equity Incentive Plan and exempt from Section 16(b) by virtue of Rule 16b-3(d)(1) and (3). These DSUs are reportable, however, as directly owned shares of common stock, rather than as a derivative security in Table II, because any and all underlying DSUs are payable, at such time as they are to be settled, solely in common stock. See Lincoln National Corp. (March 20, 1992) (Q.3). The DSUs vest as follows: 1/4 on 8/31/2026, 1/4 on 11/30/2026, 1/4 on 2/28/2027 and 1/4 on 5/31/2027. --- Signature --- /s/ /s/ Theresa E. Wagler by Power of Attorney (2026-06-01)