Insider trade

Officer sold ~$256K of AMPH shares in the open market

Traded Dec 17, 2025 · Filed Dec 18, 2025

~$256K
Approx. value · 9,787 sh @ $26.20: 138K
Holds after · shares reported: −2.7%
stock since the trade · S&P 500 +15.4%, $26.07 → $25.37 on Oct 5

Why it stands out

Amphstar Pharmaceuticals's SENIOR EVP, PRODUCTION CENTER sold $256K of Amphstar Pharmaceuticals shares. The filing does not indicate a pre-arranged trading plan.

Written from the filing's own figures. OQRO describes what was reported and never tells you what to buy or sell

View the official recordSEC Form 4 — Statement of Changes in Beneficial Ownership

All the details

Dates, kept separate

Transaction date: Dec 17, 2025
Reporting period: Not applicable
Filed with the SEC: Dec 18, 2025

Officer$100K–$500K

Context

Classification

open market sale

Code S — open-market or private sale

Absolute commitment

~$256,379

Shares × reported transaction price

Timing vs results

41 days after results of Nov 6, 2025, 71 days before results of Feb 26, 2026

Results dates are the company's own 8-K (Item 2.02). Many companies only let insiders trade in a window after results

Planned / mechanical clue

None found in footnotes

Only flagged when a footnote says so; never inferred

After it was reported

After	Stock	S&P 500	Difference
7 days	+1.9%	+1.4%	+0.5%
30 days	−2.4%	−0.4%	−2.0%
90 days	−26.5%	−3.0%	−23.5%
180 days	−27.0%	+8.9%	−35.9%

Past results only. Not a forecast.

Source receipt

Record ID: 0001645326-25-000004
Filed / recorded: Dec 18, 2025, 10:23 PM UTC
Added to OQRO: Oct 6, 2026, 9:54 PM UTC
Parser: form4-xml-v2
Data quality: Verified: identifiers matched exactly
Issuer: Amphastar Pharmaceuticals, Inc.
Issuer CIK: 1297184
Ticker: AMPH
Reporting person: Rong Zhou
Relationship: Officer
Officer title: SENIOR EVP, PRODUCTION CENTER
Security: Common Stock
Table: Non-derivative (Table I)
Transaction date: Dec 17, 2025
Transaction code: S
Shares / units: 9,787
Price per share: $26.20
Acquired / disposed: Disposed (D)
Shares owned after: 138,043
Ownership form: Direct
Amendment: No

Footnotes from the filing

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.97 to $26.50, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.