Fastenal 4: Papenfuss Donnalee Kathleen bought 1,364 shares at $13.75 o… (Aug 17, 2026)

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-08-13 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: FASTENAL CO (FAST) CIK: 0000815556 --- Reporting Owner --- Name: Papenfuss Donnalee Kathleen CIK: 0002043506 Role: Officer (EVP-Strategy and Communication) --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock Date: 2026-08-13 | Code: M (Exercise of derivative) Shares: +1,364 | Price: $13.75 Total Value: $18,755.00 Shares Owned After: 1,364 | Ownership: D (Direct) [Transaction #2] Security: Common Stock Date: 2026-08-13 | Code: S (Open market sale) Shares: -1,364 | Price: $51.42 Total Value: $70,132.11 Shares Owned After: 0 | Ownership: D (Direct) [Transaction #3] Security: Common Stock Date: 2026-08-13 | Code: M (Exercise of derivative) Shares: +7,894 | Price: $19.00 Total Value: $149,986.00 Shares Owned After: 7,894 | Ownership: D (Direct) [Transaction #4] Security: Common Stock Date: 2026-08-13 | Code: S (Open market sale) Shares: -7,894 | Price: $51.38 Total Value: $405,626.09 Shares Owned After: 0 | Ownership: D (Direct) --- Derivative Transactions --- [Transaction #1] Security: Employee Stock Option (Right to Buy) Date: 2026-08-13 | Code: M (Exercise of derivative) Shares: -1,364 | Price: $0.00 Exercisable: N/A | Expires: 2027-12-31 Shares Owned After: 0 | Ownership: D (Direct) Footnotes: [F2] The option will vest and become exercisable over a period of eight years, with 25% of the option vesting and becoming exercisable two years after the relevant vesting period, and the remainder vesting and becoming exercisable proportionately each year thereafter. [Transaction #2] Security: Employee Stock Option (Right to Buy) Date: 2026-08-13 | Code: M (Exercise of derivative) Shares: -7,894 | Price: $0.00 Exercisable: N/A | Expires: 2029-12-31 Shares Owned After: 0 | Ownership: D (Direct) Footnotes: [F3] The option was previously reported in a Form 3 filing on 11/6/2024 and the amounts reported on this Form 4 are adjusted to reflect a 2-for-1 stock split on May 21, 2025. [F3] The option was previously reported in a Form 3 filing on 11/6/2024 and the amounts reported on this Form 4 are adjusted to reflect a 2-for-1 stock split on May 21, 2025. [F4] The option will vest and become exercisable over a period of five years, with 40% of the option vesting and becoming exercisable two years following the date of grant, and the remainder vesting and becoming exercisable proportionately on each anniversary of the grant date. [F3] The option was previously reported in a Form 3 filing on 11/6/2024 and the amounts reported on this Form 4 are adjusted to reflect a 2-for-1 stock split on May 21, 2025. --- Holdings --- [Holding #1] Security: Common Stock Ownership: I (Indirect) Footnotes: [F1] Shares attributed to reporting person's account within issuer's 401(K) Plan and includes an additional 345 shares acquired in the account since the last report on 6/9/2025. --- Footnotes (Complete Index) --- F1: Shares attributed to reporting person's account within issuer's 401(K) Plan and includes an additional 345 shares acquired in the account since the last report on 6/9/2025. F2: The option will vest and become exercisable over a period of eight years, with 25% of the option vesting and becoming exercisable two years after the relevant vesting period, and the remainder vesting and becoming exercisable proportionately each year thereafter. F3: The option was previously reported in a Form 3 filing on 11/6/2024 and the amounts reported on this Form 4 are adjusted to reflect a 2-for-1 stock split on May 21, 2025. F4: The option will vest and become exercisable over a period of five years, with 40% of the option vesting and becoming exercisable two years following the date of grant, and the remainder vesting and becoming exercisable proportionately on each anniversary of the grant date. --- Signature --- /s/ /s/ John J. Milek, Attorney-in-Fact (2026-08-17)