Halliburton

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-05-05 10b5-1 Pre-arranged Plan: Yes --- Issuer --- Name: HALLIBURTON CO (HAL) CIK: 0000045012 --- Reporting Owner --- Name: Maxwell Michael Casey CIK: 0002107660 Role: Officer (President - Western Hemisphere) --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock Date: 2026-05-05 | Code: S (Open market sale) Shares: -13,566 | Price: $41.84 Total Value: $567,601.44 Shares Owned After: 100,544.783 | Ownership: D (Direct) Footnotes: [F1] The sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 3, 2026. [Transaction #2] Security: Common Stock Date: 2026-05-05 | Code: S (Open market sale) Shares: -6,782 | Price: $42.00 Total Value: $284,844.00 Shares Owned After: 93,762.783 | Ownership: D (Direct) Footnotes: [F1] The sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 3, 2026. [F2] Includes 656.906 shares of stock purchased through the Halliburton Company Employee Stock Purchase Plan for the period ending March 31, 2026. --- Footnotes (Complete Index) --- F1: The sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 3, 2026. F2: Includes 656.906 shares of stock purchased through the Halliburton Company Employee Stock Purchase Plan for the period ending March 31, 2026. --- Signature --- /s/ /s/ Sarah I. Rubenfeld, by Power of Attorney (2026-05-06)