Insider · CIK 0001645326
Rong Zhou
Files at AMPH (Amphastar Pharmaceuticals, Inc.). First filing Nov 13, 2024, latest Sep 17, 2026.
Rong Zhou files SEC Form 4 as officer at AMPH (Amphastar Pharmaceuticals, Inc.). Since Nov 13, 2024, Rong Zhou has reported 0 open-market buys worth $0 and 5 open-market sells worth $1.6M, the latest filed on Sep 17, 2026.
A track record needs three past buys with six months of prices behind them; Rong Zhou has 0, so none is measured yet.
The newest scored trade: sold $239k of AMPH on Sep 16, 2026, filed Sep 17, 2026, scored 21 (weak). In the last 12 months: 0 buys worth $0 and 3 sells worth $571k.
Where the trades landed
Last year at the company this insider has traded most, with each buy and sell on the bar it happened.
AMPH: Amphastar Pharmaceuticals, Inc.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
Signals
This insider’s open-market buys and sells, scored.
| Score | Company | Value | Holdings | Price context | Filed |
|---|---|---|---|---|---|
| 21Weak | Amphastar Pharmaceuticals, Inc. | $239k 10,000 shares | -6% | +42% from low-19% from high | |
| 23Weak | AMPHsell Amphastar Pharmaceuticals, Inc. | $75k 3,187 shares | -2% | +41% from low-23% from high | |
| 21Weak | Amphastar Pharmaceuticals, Inc. | $256k 9,787 shares | -7% | +26% from low-36% from high | |
| 33Weak | Amphastar Pharmaceuticals, Inc. | $673k 15,000 shares | -12% | - | |
| 30Weak | Amphastar Pharmaceuticals, Inc. | $337k 6,893 shares | -6% | - |
Planned sales
Form 144 notices this insider filed before selling restricted or control stock, newest first.
| Filed | Company | Shares | Value | Sale date | Past 3 months |
|---|---|---|---|---|---|
| Nov 28, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | 20,000 0.04% of outstanding | $500k | Nov 28, 2025 | none |
| Nov 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | 31,680 0.07% of outstanding | $1.5M | Nov 12, 2024 | $338k |
Transactions
Every row this insider has filed, 28 in all, newest first.
| Date | Company | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Sep 16, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock | +10,000 | $13.35 | $134k | 179,203 | 26 d ago |
| Sep 16, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock | -10,000 | $23.94 | $239k | 169,203 | 26 d ago |
| Sep 16, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative | -10,000 | $0.00 | $0 | 19,424 | 26 d ago |
| Sep 2, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock | -3,187 | $23.63 | $75k | 169,203 | 40 d ago |
| Mar 15, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,225 | $18.18 | $22k | 171,554 | Mar 17, 2026 |
| Mar 9, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Common Srock | +39,432 | $0.00 | $0 | 174,994 | Mar 11, 2026 |
| Mar 10, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -2,215 | $18.91 | $42k | 172,779 | Mar 11, 2026 |
| Mar 9, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Employee Stock Option (right to buy)derivative | +81,341 | $0.00 | $0 | 81,341 | Mar 11, 2026 |
| Mar 6, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,357 | $19.34 | $26k | 135,562 | Mar 10, 2026 |
| Mar 4, 2026 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,124 | $19.96 | $22k | 136,919 | Mar 6, 2026 |
| Dec 17, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock | +9,787 | $11.33 | $111k | 147,830 | Dec 18, 2025 |
| Dec 17, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock | -9,787 | $26.20 | $256k | 138,043 | Dec 18, 2025 |
| Dec 17, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative | -9,787 | $0.00 | $0 | 0 | Dec 18, 2025 |
| Mar 15, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,222 | $26.66 | $33k | 139,464 | Mar 18, 2025 |
| Mar 17, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Srock | -1,967 | $27.69 | $54k | 137,497 | Mar 18, 2025 |
| Mar 10, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Common Srock | +24,692 | $0.00 | $0 | 140,686 | Mar 12, 2025 |
| Mar 10, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | AGrant or award Employee Stock Option (right to buy)derivative | +52,437 | $0.00 | $0 | 52,437 | Mar 12, 2025 |
| Mar 6, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,354 | $28.32 | $38k | 115,994 | Mar 10, 2025 |
| Mar 4, 2025 | AMPH Amphastar Pharmaceuticals, Inc. | FTax withholding Common Stock | -1,121 | $27.62 | $31k | 117,348 | Mar 6, 2025 |
| Dec 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock | +7,000 | $11.33 | $79k | 125,469 | Dec 16, 2024 |
| Dec 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock | -7,000 | $44.43 | $311k | 118,469 | Dec 16, 2024 |
| Dec 13, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock | +8,000 | $11.33 | $91k | 126,469 | Dec 16, 2024 |
| Dec 13, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock | -8,000 | $45.23 | $362k | 118,469 | Dec 16, 2024 |
| Dec 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative | -7,000 | $0.00 | $0 | 17,787 | Dec 16, 2024 |
| Dec 13, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative | -8,000 | $0.00 | $0 | 9,787 | Dec 16, 2024 |
| Nov 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Common Stock | +6,893 | $14.95 | $103k | 125,281 | Nov 13, 2024 |
| Nov 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | SOpen-market sale Common Stock | -6,893 | $48.88 | $337k | 118,388 | Nov 13, 2024 |
| Nov 12, 2024 | AMPH Amphastar Pharmaceuticals, Inc. | MOption exercise Employee Stock Option (right to buy)derivative | -6,893 | $0.00 | $0 | 0 | Nov 13, 2024 |
Questions about Rong Zhou
Answered from the filings on this page, as of the latest one.
Is Rong Zhou buying or selling?
In the last 12 months Rong Zhou reported 0 open-market buys worth $0 and 3 open-market sells worth $571k on SEC Form 4; the latest was sold $239k of AMPH on Sep 16, 2026. Grants, option exercises and tax withholding are not counted.
How did Rong Zhou's past buys perform?
Not measured yet. InsiderTell needs three past buys with six months of prices to publish a track record, and Rong Zhou has 0.
Where does Rong Zhou file Form 4?
Rong Zhou has filed Form 4 at AMPH (Amphastar Pharmaceuticals, Inc.) as SENIOR EVP, PRODUCTION CENTER. A Form 4 is required of officers, directors and holders of more than 10% of a share class within two business days of a trade.
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.