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RZ
Insider

Rong Zhou

SENIOR EVP, PRODUCTION CENTER

Rong Zhou (SENIOR EVP, PRODUCTION CENTER) filed 2 Form 4 reports in the trailing twelve months (0 purchases, 2 sales), most often in Amphastar Pharmaceuticals, Inc. (AMPH). The largest single filing was $256K of AMPH (9,787 sh × $26.20, as filed), executed Dec 17 2025.

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Return, ttmiAverage return per filing, trailing twelve months
no purchases on file
Delay-adjustediThe same average, entered at disclosure dates
returns measure stock purchases only
Filings, ttm
2
0 buys · 2 sells
Median delay
execution → disclosure
Volume, ttmiDollar value disclosed in the trailing twelve months
$496K
shares × price, as filed
Last traded
Sep 16
Filed Sep 17

Median ADV $12.0M across their filed names

Open performance
Volume by month
$673K$336K$0Oct 2024Apr 2025Oct 2025Apr 2026Nov 2024 · sells $337KDec 2024 · sells $673KDec 2025 · sells $256KSep 2026 · sells $239K
Buys $0 Sells $1.5M

Shares × price, as filed · by filing month · past 24 months

Sectors filed on
Healthcare 2 filings

Sector per market data · by filing · past 12 months

Most traded names
AMPH Amphastar Pharmaceuticals, Inc. AMPH · 0 buys · 4 sells 4 filings
Recent filings
AMPHSALE Amphastar Pharmaceuticals, Inc. View filing → $239K
10,000 sh × $23.94
Exec Sep 16
Filed Sep 17 · 6:19 PM ET
AMPHSALE Amphastar Pharmaceuticals, Inc. View filing → $256K
9,787 sh × $26.20
Exec Dec 17 2025
Filed Dec 18 2025 · 5:30 PM ET
AMPHSALE Amphastar Pharmaceuticals, Inc. View filing → $673K
15,000 sh across 2 lots
Exec Dec 12 2024
Filed Dec 16 2024 · 5:30 PM ET
AMPHSALE Amphastar Pharmaceuticals, Inc. View filing → $337K
6,893 sh × $48.88
Exec Nov 12 2024
Filed Nov 13 2024 · 5:30 PM ET
AMPHSALE Amphastar Pharmaceuticals, Inc. View filing → $145K
3,000 sh × $48.26
Exec Sep 13 2024
Filed Sep 17 2024 · 5:30 PM ET