Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Liawatidewi Yakob
 2. Date of Event Requiring Statement (Month/Day/Year)
06/07/2018		 3. Issuer Name and Ticker or Trading Symbol
Amphastar Pharmaceuticals, Inc. [AMPH]
(Last)
(First)
(Middle)
C/O AMPHASTAR PHARMACEUTICALS, INC., 11570 6TH STREET		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP Corp Admin Center
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

RANCHO CUCAMONGA, CA 91730		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 39,289 (1)
D
 
Common Stock 10,369
I
See footnote (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (right to buy)   (3) 08/28/2018 Common Stock 11,000 $ 35.32 D  
Employee Stock Option (right to buy)   (3) 08/05/2019 Common Stock 11,500 $ 20.26 D  
Employee Stock Option (right to buy)   (3) 03/08/2021 Common Stock 6,000 $ 11.41 D  
Employee Stock Option (right to buy)   (3) 12/22/2021 Common Stock 4,903 $ 14.23 D  
Employee Stock Option (right to buy)   (3) 11/07/2022 Common Stock 20,000 $ 10.48 D  
Employee Stock Option (right to buy)   (3) 07/30/2023 Common Stock 26,000 $ 10.93 D  
Employee Stock Option (right to buy)   (3) 04/14/2024 Common Stock 4,904 $ 14.4 D  
Employee Stock Option (right to buy)   (4) 03/26/2025 Common Stock 17,800 $ 14.95 D  
Employee Stock Option (right to buy)   (5) 03/17/2026 Common Stock 29,801 $ 11.33 D  
Employee Stock Option (right to buy)   (6) 03/16/2027 Common Stock 23,352 $ 13.35 D  
Employee Stock Option (right to buy)   (7) 03/15/2028 Common Stock 18,892 $ 19.79 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Liawatidewi Yakob
C/O AMPHASTAR PHARMACEUTICALS, INC.
11570 6TH STREET
RANCHO CUCAMONGA, CA 91730		       SVP Corp Admin Center  

Signatures

/s/ Eva Wen by power of attorney 06/18/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Of the reported shares, 21,801 shares are represented by restricted stock units, or RSUs which vest as follows: (i) 1,680 RSUs vest on March 26, 2019; (ii) 4,964 RSUs vest in two equal annual installments beginning on March 17, 2019; (iii) 7,022 RSUs vest in three equal annual installments beginning on March 16, 2019; and (iv) 8,135 RSUs vest in four equal annual installments beginning on March 15, 2019.
(2) The reported shares are held of record by the Yakob and Sunmoon Trust dated July 25, 2013 for which the reporting person serves as a trustee.
(3) Shares subject to the option are fully vested and immediately exercisable.
(4) Shares subject to the option vest in four equal annual installments beginning on March 26, 2016.
(5) Shares subject to the option vest in four equal annual installments beginning on March 17, 2017.
(6) Shares subject to the option vest in four equal annual installments beginning on March 16, 2018.
(7) Shares subject to the option vest in four equal annual installments beginning on March 15, 2019.
 
Remarks:
Exhibit 24  - Power of Attorney

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