Reporting owner · CIK 0001645326
Zhou Rong
SEC Form 4 history across 1 companies, 4 transactions and 2 filings.
SE, PCSENIOR EVP, PRODUCTION CENTERAmphastar Pharmaceuticals, Inc.
Open-market transaction mix0% buys0 buys · 2 sales
Available history · Sep 02, 2026 – Sep 16, 2026
Latest insider transactions
Form 4 filings from available history.| Company | Insider | Activity | Disclosed value | Filed (ET) |
|---|---|---|---|---|
AMPHAmphastar Pharmaceuticals, Inc. | Zhou RongSE · PC | M · exerciseDerivative securitySEC filing ↗ | $0View disclosure → | |
AMPHAmphastar Pharmaceuticals, Inc. | Zhou RongSE · PC | S · saleSEC filing ↗ | -$239kView disclosure → | |
AMPHAmphastar Pharmaceuticals, Inc. | Zhou RongSE · PC | M · exerciseSEC filing ↗ | $133kView disclosure → | |
AMPHAmphastar Pharmaceuticals, Inc. | Zhou RongSE · PC | S · saleSEC filing ↗ | -$75.3kView disclosure → |
Latest Form 4 facts
Quick context from source filings
Latest open-market transaction
sale at Amphastar Pharmaceuticals, Inc. on Sep 16, 2026 valued at $239,404.
Review SEC filingLatest buy
No open-market insider purchase is available.
Latest sale
sale at Amphastar Pharmaceuticals, Inc. on Sep 16, 2026 valued at $239,404.
Review SEC filingMonthly open-market activity
Last 1 reported months · purchases and sales
View exact monthly values
| Month | Purchases | Sales | Buy value | Sale value | Net value |
|---|---|---|---|---|---|
| Sep 2026 | 0 | 2 | $0.00 | $314,709.94 | -$314,709.94 |
Net value is disclosed purchases minus sales, not profit. A dash means the value is unavailable.
Ownership and transaction size
Ownership and ticket size
Average P/S size$157.4K
Median P/S size$157.4K
Direct4
Indirect0
Sep 16, 2026exercise
Filing-only signals
Deterministic matches in this insider's history
No filing-only signal badges matched this history.
Associated companies
Companies in the disclosed reporting history
Open-market buy performance
90-day forward return on this insider's open-market purchases
No open-market purchases in available history
A 90-day purchase return requires an open-market buy. No eligible purchases are recorded in this history.
Disclosed ownership
How reported shareholdings evolved
Non-derivative shares held after reported transactions—not stock prices or a complete portfolio.
3 observations · Sep 2, 2026 – Sep 16, 2026. Window ends at the latest available report, not today.
Selected observation · Sep 16, 2026169,203 shares reported
Inspect transaction View exact observations and source transactions
| Transaction date | Shares held after | Filed | Source |
|---|---|---|---|
| Sep 2, 2026 | 169,203 | Sep 3, 2026 | View transaction |
| Sep 16, 2026 | 179,203 | Sep 17, 2026 | View transaction |
| Sep 16, 2026 | 169,203 | Sep 17, 2026 | View transaction |
Securities and direct/indirect ownership contexts are kept separate and never summed. Joint filings may associate the same disclosed row with multiple owners. Unknown values are omitted, not treated as zero. Lines connect observations for readability; they do not establish holdings between filings, cost basis, or current ownership. Amendments and stock splits require reviewing the source.
Zhou Rong Insider Activity FAQ
SEC Form 4 context
Who is Zhou Rong?
Zhou Rong is a reporting owner in SEC Form 4 filings with reporting owner CIK 0001645326.
Which companies has Zhou Rong reported transactions for?
Amphastar Pharmaceuticals, Inc.
When was Zhou Rong's latest insider buy?
No open-market insider purchase is available for this period.
When was Zhou Rong's latest insider sale?
sale at Amphastar Pharmaceuticals, Inc. on Sep 16, 2026 valued at $239,404.
Where can I see the original SEC filings?
Each transaction row links directly to the source SEC filing so the reported Form 4 details can be reviewed.
Are performance metrics included?
The profile shows average and median 90-day stock returns after open-market purchases when price coverage is available. These are unadjusted stock returns, not realized trading gains. Win rates, benchmark-adjusted returns and conviction scores are not calculated.