X0508 4 2025-11-05 0 0001003078 MSC INDUSTRIAL DIRECT CO INC MSM 0001200390 GERSHWIND ERIK C/O MSC INDUSTRIAL DIRECT CO., INC. 515 BROADHOLLOW ROAD MELVILLE NY 11747 1 1 0 0 Chief Executive Officer 0 Class A Common Stock, $0.001 par value 2025-11-05 4 M 0 4782 0 A 1571971 D Class A Common Stock, $0.001 par value 2025-11-05 4 M 0 770.717 0 A 1572742 D Class A Common Stock, $0.001 par value 2025-11-05 4 F 0 2834.717 86.68 D 1569907 D Class A Common Stock, $0.001 par value 44513 I See footnotes Class A Common Stock, $0.001 par value 354963 I See footnotes Class A Common Stock, $0.001 par value 61027 I See footnotes Class A Common Stock, $0.001 par value 102435 I See footnotes Restricted Stock Units (RSU) 2025-11-05 4 M 0 4782 0 D Class A Common Stock, $0.001 par value 4782 0 D Dividend Equivalent Units 2025-11-05 4 M 0 770.717 0 D Class A Common Stock, $0.001 par value 770.717 2005 D Each RSU represents a contingent right to receive one share of Common Stock. The dividend equivalent units accrued with respect to outstanding awards of restricted stock units (RSUs) and vest at the same time(s) as the underlying RSUs. Each dividend equivalent unit represents a contingent right to receive one share of Common Stock. Disposition of Class A Common Stock to the Issuer to cover tax withholding obligations arising from the vesting of RSUs and DEUs. The Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein. Represents shares held by Grantor Retained Annuity Trusts of which the Reporting Person is the sole annuitant and trustee. Represents shares held by trusts over whose trustee the Reporting Person can exercise remove and replace powers. Represents shares held by a trust of which the Reporting Person is a co-trustee and beneficiary. Represents shares held by a Trust of which the Reporting Person is a trustee. 19,126 RSUs were granted on November 5, 2021. 4,781 RSUs vested on each of November 5, 2022 and November 5, 2023, and 4,782 RSUs vested on each of November 5, 2024 and November 5, 2025. /s/ Erik Gershwind 2025-11-07