Zhou Rong 4

What Happened

• Zhou Rong, Senior EVP, Production Center at Amphastar Pharmaceuticals, had 1,124 shares withheld on March 4, 2026 to satisfy tax liability related to vested restricted stock units (RSUs). The withholding was reported as a disposition at $19.96 per share, for a value of $22,435.
• This was a tax-withholding/net settlement of RSUs (routine), not an open-market sale indicating a directional investment decision.

Key Details

• Transaction date and price: 2026-03-04 at $19.96 per share.
• Shares withheld/disposed: 1,124 shares; total value ~$22,435.
• Reason/code: F — payment of exercise price or tax liability (footnote F1 confirms withholding for RSU tax).
• Shares held of record: Some shares are held by the Zhou Family Trust (reporting person is trustee) and by the reporting person’s spouse (footnotes F2, F3).
• Filing timeliness: Form 4 filed 2026-03-06 (timely — within the normal two-business-day reporting window).
• Shares owned after transaction: Not specified in the summary details provided.

Context

• This was a net share withholding to cover taxes on vested RSUs (a routine administrative transaction), not a market sale or new purchase. Such withholdings are common and generally don’t by themselves indicate insider sentiment about the company.