DIETRICH DOUGLAS T 4

What Happened
Douglas T. Dietrich, Chairman and CEO of Minerals Technologies Inc. (MTX), had 10,033 deferred restricted stock units (DRSUs) convert into common shares on January 21, 2026. The DRSUs converted at $0 (no cash exercise). To satisfy tax withholding, the company withheld 5,630 shares at $66.92 each, totaling $376,760. After withholding, Dietrich received a net of 4,403 shares.

Key Details

• Transaction date: January 21, 2026; Form 4 filed January 23, 2026 (filed timely).
• Conversion (code M): 10,033 DRSUs converted into 10,033 shares @ $0.00.
• Tax withholding (code F): 5,630 shares withheld/disposed @ $66.92 = $376,760.
• Net shares received: 4,403 (10,033 converted − 5,630 withheld).
• Shares owned after transaction: Not disclosed in this filing.
• Footnotes: F1 confirms shares were withheld by Minerals Technologies to satisfy tax obligations. F2–F4 note the report is based on a Plan Statement dated Jan 21, 2026; each DRSU equals one share; the DRSUs were granted Jan 21, 2025 and vest in three equal annual installments beginning Jan 21, 2026.

Context
This was a routine vesting/conversion of restricted stock units, not an open-market sale or discretionary purchase. The withholding of shares to cover taxes is a common administrative step and does not necessarily indicate buying or selling sentiment. The vesting represents the first of three annual installments from the Jan 21, 2025 grant.