# EDGAR Filing Document

**Accession Number:** 0001297184
**File Stem:** 0001104659-26-027814
**Filing Date:** 2026-3
**Character Count:** 4280
**Document Hash:** ae62be14cefdccc0f99bd45e8db3783e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-027814.hdr.sgml**: 20260316

**ACCESSION NUMBER**: 0001104659-26-027814

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 11

**CONFORMED PERIOD OF REPORT**: 20260312

**ITEM INFORMATION**: Other Events

**FILED AS OF DATE**: 20260316

**DATE AS OF CHANGE**: 20260316

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Amphastar Pharmaceuticals, Inc.
- **CENTRAL INDEX KEY:** 0001297184
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 330702205
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-36509
- **FILM NUMBER:** 26754292

**BUSINESS ADDRESS:**
- **STREET 1:** 11570 SIXTH STREET
- **CITY:** RANCHO CUCAMONGA
- **STATE:** CA
- **ZIP:** 91730
- **BUSINESS PHONE:** 909-980-9484

**MAIL ADDRESS:**
- **STREET 1:** 11570 SIXTH STREET
- **CITY:** RANCHO CUCAMONGA
- **STATE:** CA
- **ZIP:** 91730

?xml version='1.0' encoding='ASCII'? Amphastar Pharmaceuticals, Inc._March 12, 2026

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**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**PURSUANT TO SECTION 13 OR 15(d) OF THE**

**SECURITIES EXCHANGE ACT OF 1934**

Date of Report (Date of earliest event Reported): March 12, 2026

**Amphastar Pharmaceuticals, Inc.**

(Exact Name of Registrant as Specified in Charter)

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| | | |
|:---|:---|:---|
| **Delaware** | **001-36509** | **33-0702205** |
| (State or Other Jurisdiction of<br>Incorporation) | (Commission File Number) | (I.R.S. Employer Identification<br>Number) |

---

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| | |
|:---|:---|
| **11570 6th Street** |  |
| **Rancho Cucamonga, California** | **91730** |
| (Address of Principal Executive Offices) | (Zip Code) |

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Registrant's telephone number, including area code: **(909) 980-9484**

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

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| | | |
|:---|:---|:---|
| T<br>|  |  |
| Title of each class | Trading Symbol(s) | Name of each exchange on which registered |
| Common Stock, par value $0.0001 per share | AMPH | The Nasdaq Stock Market LLC |

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Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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**Item 8.01.** **Other Events**

Purchases may be made through the open market and private block transactions pursuant to Rule 10b5-1 plans, privately negotiated transactions, or other means, as determined by the Company's management and in accordance with the requirements of the Securities and Exchange Commission and applicable laws.

The timing and actual number of shares repurchased will depend on a variety of factors including price, corporate and regulatory requirements, and other conditions.

**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | | |
|:---|:---|:---|
|  | AMPHASTAR PHARMACEUTICALS, INC. | AMPHASTAR PHARMACEUTICALS, INC. |
| Date: March 16, 2026 |  |  |
|  | By: | **/S/WILLIAM J. PETERS** |
|  |  | William J. Peters |
|  |  | Chief Financial Officer, Executive Vice President and Treasurer |

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