Insider trade

William J Peters, CFO at Amphstar Pharmaceuticals, Inc., sold ~$184K of Amphstar Pharmaceuticals, Inc. shares.

~$184K
Approx. value · 8,180 sh @ $22.48
173K
Holds after · shares reported
Traded
Aug 7, 2026
Filed
Aug 11, 2026

The story around this disclosure

Every dated public record OQRO holds about the company from 60 days before to 120 days after, oldest first. It shows what was going on; none of it is a stated reason for the trade.

  1. Jul 9, 2026Company filing · Form 8-K · Executive changeChanged a top executive or board member“On July 9, 2026, the Board of Directors (the “Board”) of Amphastar Pharmaceuticals, Inc. (the “Company”), upon the recommendation of the Nominating and Corporate Governance Committee of the Board (the “Nominating Committee”), approved an increase to the authorized number of directors permitted to serve on the Board from ten (10) to eleven (11) directors and appointed Anthony Pierce, to serve as a Class III director,…”
  2. Aug 6, 2026Company filing · Form 8-K · ResultsReported its results
  3. Aug 7, 2026 · this disclosureInsiderCFO sold ~$184K of AMPH shares in the open market

What came next

  1. Aug 11, 2026InsiderDirector sold ~$162K of AMPH shares in the open market
  2. Sep 2, 2026InsiderOfficer sold ~$75K of AMPH shares in the open market
  3. Sep 16, 2026InsiderOfficer sold ~$239K of AMPH shares in the open market
  4. Sep 21, 2026InsiderCFO sold ~$103K of AMPH shares in the open market
View the official recordSEC Form 4

How to read SEC Form 4

Form 4 is the filing that officers, directors and owners of more than 10% of a US-listed company must send to the SEC within two business days after they buy, sell or otherwise change their holding of the company's stock.

Full guide: What is an SEC Form 4?

What else is on file for Amphstar Pharmaceuticals, Inc.

For Amphstar Pharmaceuticals, Inc., OQRO holds 5 insider filings (SEC Form 4 or Form 144) dated in the last 90 days.

These are records OQRO holds, counted by their date, not a measure of how much trading took place. Routine paperwork such as option exercises and tax withholding is left out. Everything for the company is on its AMPH page.

Other recent filings by William J Peters, CFO, EVP & TREASURER

The full history of William J Peters, CFO, EVP & TREASURER is on the profile page.

How this filing works

Other disclosures at Amphstar Pharmaceuticals, Inc.

Everything OQRO holds on this company is on its AMPH page.

This is one filing. OQRO holds the rest

Insider trades filed with the SEC, stock trades disclosed by members of Congress, fund holdings from 13F filings and federal contract awards, each one in plain words next to its official filing. On this page it opens why the trade stands out, what the company did around that time, the price since, and every field of the form.

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