Sicinski Matthew B. 4

What Happened

• Matthew B. Sicinski, Senior Vice President and Chief Accounting Officer of Summit Midstream Corp (SMC), had 3,593 corporation restricted stock units (CRSUs) vest on January 16, 2026. The vesting/conversion is reported as an exercise/conversion of a derivative security.
• Of the 3,593 vested shares, 1,066 common shares were withheld to cover tax liability at $26.81 per share, for a withholding value of $28,579. Net shares delivered to Sicinski were 3,593 - 1,066 = 2,527 shares.
• This was not an open-market purchase or sale by the insider but settlement of an award (vested RSUs/CRSUs).

Key Details

• Transaction date: January 16, 2026. Filing date: January 21, 2026 (filed 5 days after the transaction; appears late relative to the typical two-business-day Form 4 deadline).
• Reported items: 3,593 CRSUs converted/settled (reported as derivative exercise/conversion); 1,066 shares withheld for taxes at $26.81 each (value $28,579).
• Shares owned after the transaction: Not specified in the provided excerpt of the filing.
• Footnotes: CRSUs are the economic equivalent of common stock (F1). Withholding was used to pay tax liability (F2). One‑third of the award vested on Jan 16, 2026 with remaining tranches vesting later (F3–F5). CRSUs may be settled in stock or cash and do not expire (F4).

Context

• This is a routine vesting/settlement of restricted stock units rather than a market buy or sale; the withholding of shares to cover taxes is a common cashless settlement practice. The filing shows both the conversion of the derivative (CRSUs) and the tax-withholding disposition; the $0 disposition entry reflects conversion/settlement of the derivative security.