AMPH Insider Trading

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Insider Trading History
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About

Insider Ownership Percentage: 27.50%

Insider Buying (Last 12 Months): $0.00

Insider Selling (Last 12 Months): $1,006,452.46

Amphastar Pharmaceuticals Insider Trading History Chart

Amphastar Pharmaceuticals Share Price & Price History

^$19.50

▼ -0.031 (-0.16%)

As of 03/27/2026 10:30 AM ET

Days: 30 | 90 | 365

Amphastar Pharmaceuticals Insider Trading History

Transaction Date	Insider Name	Title	Buy/Sell	Number of Shares	Average Share Price	Total Transaction	Shares Held After Transaction
12/17/2025	Rong Zhou	EVP	Sell	9,787	$26.20	$256,419.40	138,043
12/12/2025	Floyd F. Petersen	Director	Sell	2,426	$25.92	$62,881.92	71,368
12/11/2025	Floyd F. Petersen	Director	Sell	1,737	$25.69	$44,623.53	73,794
11/25/2025	Richard K. Prins	Director	Sell	4,179	$27.10	$113,250.90	35,183
11/13/2025	Floyd F. Petersen	Director	Sell	16,679	$26.49	$441,826.71	75,531
11/3/2025	Floyd F. Petersen	Director	Sell	500	$25.27	$12,635.00	75,531
10/1/2025	Floyd F. Petersen	Director	Sell	500	$27.20	$13,600.00	76,031
8/1/2025	Floyd F. Petersen	Director	Sell	500	$20.83	$10,415.00	77,031
7/2/2025	Floyd F. Petersen	Director	Sell	500	$23.47	$11,735.00	77,531
6/2/2025	Floyd F. Petersen	Director	Sell	500	$25.67	$12,835.00	72,909
5/1/2025	Floyd F. Petersen	Director	Sell	500	$24.08	$12,040.00	73,409
4/1/2025	Floyd F. Petersen	Director	Sell	500	$28.38	$14,190.00	73,909
3/4/2025	William J. Peters	CFO	Sell	4,231	$27.54	$116,521.74	97,363
12/12/2024	Rong Zhou	EVP	Sell	7,000	$44.42	$310,940.00	118,469
12/9/2024	Richard K. Prins	Director	Sell	10,000	$43.77	$437,700.00	30,471
11/12/2024	Richard K. Prins	Director	Sell	5,000	$48.80	$244,000.00	31,471
11/12/2024	Rong Zhou	EVP	Sell	6,893	$48.88	$336,929.84	118,388
11/6/2024	William J. Peters	CFO	Sell	7,426	$52.05	$386,523.30	94,103
11/6/2024	Yakob Liawatidewi	EVP	Sell	5,214	$52.05	$271,388.70	74,938
9/5/2024	Floyd F. Petersen	Director	Sell	3,000	$46.47	$139,410.00	75,409
8/26/2024	Rong Zhou	EVP	Sell	4,000	$48.35	$193,400.00	118,388
8/12/2024	Richard K. Prins	Director	Sell	17,101	$43.07	$736,540.07	33,971
7/31/2024	William J. Peters	CFO	Sell	10,282	$44.23	$454,772.86	94,103
6/27/2024	William J. Peters	CFO	Sell	3,596	$40.93	$147,184.28	94,103
6/10/2024	Floyd F. Petersen	Director	Sell	3,000	$41.40	$124,200.00	78,409
6/3/2024	Floyd F. Petersen	Director	Sell	500	$42.65	$21,325.00	78,333
5/1/2024	Floyd F. Petersen	Director	Sell	500	$41.67	$20,835.00	78,833
4/1/2024	Floyd F. Petersen	Director	Sell	500	$43.43	$21,715.00	79,333
3/5/2024	Michael A. Zasloff	Director	Sell	12,500	$47.18	$589,750.00	21,326
3/1/2024	Floyd F. Petersen	Director	Sell	500	$45.69	$22,845.00	79,833
2/1/2024	Floyd F. Petersen	Director	Sell	500	$53.10	$26,550.00	80,333
1/10/2024	Mary Z. Luo	COO	Sell	131,386	$54.59	$7,172,361.74	1,104,416
1/8/2024	Mary Z. Luo	COO	Sell	133,644	$58.93	$7,875,640.92	1,321,958
1/2/2024	Floyd F. Petersen	Director	Sell	500	$61.37	$30,685.00	80,833
12/4/2023	Rong Zhou	EVP	Sell	3,514	$59.58	$209,364.12	112,420
12/1/2023	Floyd F. Petersen	Director	Sell	500	$57.90	$28,950.00	81,333
12/1/2023	Rong Zhou	EVP	Sell	4,316	$58.58	$252,831.28	112,420
11/17/2023	Richard K. Prins	Director	Sell	4,000	$55.86	$223,440.00	31,895
11/13/2023	Richard K. Prins	Director	Sell	5,000	$52.50	$262,500.00	35,895
11/1/2023	Floyd F. Petersen	Director	Sell	500	$45.30	$22,650.00	81,833
10/2/2023	Floyd F. Petersen	Director	Sell	500	$45.78	$22,890.00	82,333
9/6/2023	William J. Peters	CFO	Sell	60,743	$51.75	$3,143,450.25	101,360
8/28/2023	Yakob Liawatidewi	EVP	Sell	28,816	$53.13	$1,530,994.08	69,669
8/18/2023	Richard K. Prins	Director	Sell	2,000	$52.50	$105,000.00	40,895
8/15/2023	Michael A. Zasloff	Director	Sell	12,759	$57.22	$730,069.98	33,826
6/15/2023	Rong Zhou	EVP	Sell	5,000	$51.79	$258,950.00	96,888
6/15/2023	William J. Peters	CFO	Sell	36,868	$50.85	$1,874,737.80	105,603
6/13/2023	Rong Zhou	EVP	Sell	5,000	$48.24	$241,200.00	88,313
6/2/2023	William J. Peters	CFO	Sell	11,000	$46.35	$509,850.00	105,603
6/1/2023	Howard Lee	Director	Sell	16,679	$45.02	$750,888.58	142,939
5/18/2023	Rong Zhou	EVP	Sell	10,000	$44.20	$442,000.00	87,598
5/18/2023	William J. Peters	CFO	Sell	10,500	$44.35	$465,675.00	105,148
5/17/2023	Floyd F. Petersen	Director	Sell	5,000	$43.13	$215,650.00	80,117
5/15/2023	Michael A. Zasloff	Director	Sell	7,500	$42.18	$316,350.00	43,869
5/12/2023	Richard K. Prins	Director	Sell	5,000	$42.06	$210,300.00	47,342
4/17/2023	William J. Peters	CFO	Sell	5,632	$42.35	$238,515.20	105,148
4/13/2023	William J. Peters	CFO	Sell	4,868	$42.35	$206,159.80	105,148
4/13/2023	Yakob Liawatidewi	EVP	Sell	11,494	$41.56	$477,690.64	69,215
4/10/2023	William J. Peters	CFO	Sell	10,032	$40.35	$404,791.20	105,148
4/10/2023	Yakob Liawatidewi	EVP	Sell	5,000	$40.00	$200,000.00	69,215
4/3/2023	Floyd F. Petersen	Director	Sell	491	$37.72	$18,520.52	85,117

SEC Filings (Institutional Ownership Changes) for Amphastar Pharmaceuticals (NASDAQ:AMPH)

65.09% of Amphastar Pharmaceuticals stock is owned by institutions. Institutional ownership can be a sign of analyst confidence in the fundamentals of the stock.

Institutional Buying and Selling by Quarter

Amphastar Pharmaceuticals Institutional Trading History

Reporting Date	Hedge Fund	Shares Held	Market Value	% of Portfolio	Quarterly Change in Shares	Ownership in Company
3/9/2026	Corient Private Wealth LLC	7,839	$0.21M	0.0%	-50.1%	0.017%
2/24/2026	Pacer Advisors Inc.	177,744	$4.76M	0.0%	+2,864.4%	0.387%
2/19/2026	Invesco Ltd.	501,404	$13.43M	0.0%	+28.7%	1.091%
2/19/2026	Corient Private Wealth LLC	15,339	$0.41M	0.0%	-2.4%	0.033%
2/18/2026	Vident Advisory LLC	20,409	$0.55M	0.0%	+10.7%	0.044%
2/18/2026	State of Tennessee Department of Treasury	8,619	$0.23M	0.0%	-7.3%	0.019%
2/18/2026	Fuller & Thaler Asset Management Inc.	1,394,463	$37.34M	0.1%	+3.0%	3.035%
2/18/2026	Empowered Funds LLC	165,907	$4.44M	0.0%	+10.8%	0.361%
2/18/2026	XTX Topco Ltd	48,607	$1.30M	0.0%	N/A	0.106%
2/18/2026	Voloridge Investment Management LLC	231,305	$6.19M	0.0%	-20.9%	0.503%
2/18/2026	Susquehanna Portfolio Strategies LLC	66,969	$1.79M	0.0%	+69.3%	0.146%
2/18/2026	Millennium Management LLC	290,673	$7.78M	0.0%	-58.3%	0.633%
2/18/2026	Man Group plc	14,151	$0.38M	0.0%	-56.3%	0.031%
2/18/2026	Gotham Asset Management LLC	27,802	$0.75M	0.0%	+81.0%	0.061%
2/18/2026	Balyasny Asset Management L.P.	77,467	$2.08M	0.0%	-45.4%	0.169%
2/18/2026	Bridgeway Capital Management LLC	323,549	$8.67M	0.2%	+3.6%	0.704%
2/17/2026	Freestone Grove Partners LP	27,593	$0.74M	0.0%	N/A	0.060%
2/17/2026	AQR Capital Management LLC	67,652	$1.81M	0.0%	+8.9%	0.147%
2/17/2026	Quantedge Capital Pte Ltd	91,700	$2.46M	1.2%	+103.3%	0.200%
2/17/2026	Trexquant Investment LP	113,673	$3.04M	0.0%	N/A	0.247%
2/17/2026	Jump Financial LLC	7,800	$0.21M	0.0%	N/A	0.017%
2/17/2026	Price T Rowe Associates Inc. MD	36,796	$0.99M	0.0%	-86.6%	0.080%
2/17/2026	Clark Capital Management Group Inc.	317,482	$8.50M	0.1%	+11.9%	0.691%
2/17/2026	State of Wisconsin Investment Board	17,506	$0.47M	0.0%	-17.9%	0.038%
2/17/2026	ExodusPoint Capital Management LP	14,929	$0.40M	0.0%	N/A	0.032%
2/17/2026	Rice Hall James & Associates LLC	121,176	$3.25M	0.2%	-6.3%	0.264%
2/16/2026	Squarepoint Ops LLC	14,860	$0.40M	0.0%	-69.9%	0.032%
2/16/2026	MML Investors Services LLC	14,661	$0.39M	0.0%	+73.3%	0.032%
2/16/2026	Epoch Investment Partners Inc.	1,126,585	$30.17M	0.2%	-0.7%	2.452%
2/16/2026	Bridge City Capital LLC	235,485	$6.31M	1.9%	+72.8%	0.512%
2/13/2026	Marshall Wace LLP	1,237,284	$33.13M	0.0%	+41.6%	2.693%
2/13/2026	The Manufacturers Life Insurance Company	16,402	$0.44M	0.0%	-7.7%	0.036%
2/13/2026	Corient IA LLC	7,500	$0.20M	0.2%	N/A	0.016%
2/13/2026	Public Sector Pension Investment Board	122,505	$3.28M	0.0%	-12.3%	0.267%
2/13/2026	Rafferty Asset Management LLC	7,682	$0.21M	0.0%	N/A	0.017%
2/13/2026	Arkadios Wealth Advisors	26,303	$0.70M	0.0%	-27.0%	0.057%
2/13/2026	First Trust Advisors LP	140,310	$3.76M	0.0%	-6.7%	0.305%
2/13/2026	Charles Schwab Investment Management Inc.	350,707	$9.39M	0.0%	-1.6%	0.763%
2/13/2026	State Street Corp	1,531,786	$41.02M	0.0%	+2.1%	3.334%
2/13/2026	Martingale Asset Management L P	12,400	$0.33M	0.0%	-33.0%	0.027%
2/13/2026	UBS AM a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC	55,232	$1.48M	0.0%	+1.7%	0.120%
2/12/2026	MetLife Investment Management LLC	21,075	$0.56M	0.0%	-8.7%	0.046%
2/12/2026	Commonwealth Equity Services LLC	8,742	$0.23M	0.0%	+11.2%	0.019%
2/12/2026	Renaissance Technologies LLC	544,700	$14.59M	0.0%	-7.2%	1.185%
2/12/2026	Dimensional Fund Advisors LP	1,799,685	$48.20M	0.0%	+2.5%	3.917%
2/12/2026	Federated Hermes Inc.	23,537	$0.63M	0.0%	N/A	0.051%
2/12/2026	New York State Common Retirement Fund	125,968	$3.37M	0.0%	+39.7%	0.274%
2/12/2026	Fuller & Thaler Asset Management Inc.	1,394,463	$37.34M	0.1%	+3.0%	3.035%
2/12/2026	Campbell & CO Investment Adviser LLC	30,682	$0.82M	0.0%	-30.4%	0.067%
2/12/2026	Nuveen LLC	76,101	$2.04M	0.0%	-2.1%	0.166%
2/11/2026	Empowered Funds LLC	165,907	$4.44M	0.0%	+10.8%	0.361%
2/11/2026	Janney Montgomery Scott LLC	14,230	$0.38M	0.0%	+6.2%	0.031%
2/11/2026	Deutsche Bank AG	29,557	$0.79M	0.0%	+4.1%	0.064%
2/11/2026	LPL Financial LLC	19,844	$0.53M	0.0%	+35.5%	0.043%
2/11/2026	Franklin Resources Inc.	26,045	$0.70M	0.0%	+173.4%	0.057%
2/11/2026	Brandywine Global Investment Management LLC	105,417	$2.82M	0.0%	N/A	0.229%
2/11/2026	O Shaughnessy Asset Management LLC	87,183	$2.34M	0.0%	+26.2%	0.190%
2/11/2026	Los Angeles Capital Management LLC	19,397	$0.48M	0.0%	+2.4%	0.042%
2/11/2026	Vestcor Inc	16,383	$0.44M	0.0%	+74.6%	0.036%
2/11/2026	State of Wyoming	7,561	$0.20M	0.0%	+129.1%	0.016%
2/10/2026	Cibc World Market Inc.	62,192	$1.67M	0.0%	N/A	0.135%
2/10/2026	TD Asset Management Inc	1,963,052	$52.57M	0.0%	+1.6%	4.272%
2/10/2026	Commonwealth of Pennsylvania Public School Empls Retrmt SYS	8,760	$0.24M	0.0%	-3.9%	0.019%
2/10/2026	Intech Investment Management LLC	63,232	$1.69M	0.0%	+23.6%	0.138%
2/9/2026	Geode Capital Management LLC	886,825	$23.75M	0.0%	-3.9%	1.930%
2/9/2026	Royce & Associates LP	352,297	$9.44M	0.1%	-3.8%	0.767%
2/9/2026	Hantz Financial Services Inc.	4,484	$0.12M	0.0%	+43.6%	0.010%
2/9/2026	Systematic Financial Management LP	435,580	$11.67M	0.3%	+2.9%	0.948%
2/6/2026	Legato Capital Management LLC	26,590	$0.71M	0.1%	-26.3%	0.058%
2/6/2026	LSV Asset Management	110,300	$2.95M	0.0%	+50.5%	0.240%
2/6/2026	IFP Advisors Inc	970	$26K	0.0%	-38.2%	0.002%
2/6/2026	ProShare Advisors LLC	9,083	$0.24M	0.0%	+5.3%	0.020%
2/5/2026	TD Private Client Wealth LLC	2,418	$65K	0.0%	+410.1%	0.005%
2/4/2026	Ameritas Advisory Services LLC	9,186	$0.25M	0.0%	N/A	0.020%
2/4/2026	VIRGINIA RETIREMENT SYSTEMS ET Al	12,362	$0.33M	0.0%	-8.8%	0.027%
2/3/2026	Denali Advisors LLC	211,765	$5.67M	0.6%	+56.9%	0.461%
1/29/2026	UBS Group AG	256,624	$6.87M	0.0%	-17.8%	0.558%
1/29/2026	Teachers Retirement System of The State of Kentucky	9,053	$0.24M	0.0%	-14.0%	0.020%
1/29/2026	Vanguard Group Inc.	2,608,158	$69.85M	0.0%	-0.9%	5.676%
1/29/2026	Polaris Capital Management LLC	35,532	$0.95M	0.1%	+171.2%	0.077%
1/29/2026	China Universal Asset Management Co. Ltd.	7,488	$0.20M	0.0%	-8.1%	0.016%
1/28/2026	Arizona State Retirement System	10,428	$0.28M	0.0%	-6.4%	0.023%
1/28/2026	Boston Trust Walden Corp	1,087,266	$29.12M	0.2%	-7.3%	2.366%
1/27/2026	Round Rock Advisors LLC	20,477	$0.55M	0.1%	+138.7%	0.045%
1/26/2026	Mirae Asset Global Investments Co. Ltd.	2,233	$60K	0.0%	+24.2%	0.005%
1/23/2026	Farther Finance Advisors LLC	1,381	$37K	0.0%	+46.3%	0.003%
1/23/2026	Assetmark Inc.	54,359	$1.46M	0.0%	-3.8%	0.118%
1/23/2026	State of Alaska Department of Revenue	27,916	$0.75M	0.0%	+34.3%	0.061%
1/21/2026	Yousif Capital Management LLC	8,721	$0.23M	0.0%	-6.0%	0.019%
1/16/2026	Blue Trust Inc.	1,240	$33K	0.0%	-29.9%	0.003%
1/14/2026	Exchange Traded Concepts LLC	9,418	$0.25M	0.0%	-5.7%	0.020%
1/9/2026	SG Americas Securities LLC	93,515	$2.50M	0.0%	N/A	0.204%
1/8/2026	Nordea Investment Management AB	129,144	$3.46M	0.0%	-15.8%	0.281%
1/7/2026	Significant Wealth Partners LLC	9,624	$0.26M	0.3%	-53.2%	0.021%
1/5/2026	GAMMA Investing LLC	1,685	$45K	0.0%	+37.8%	0.004%
12/15/2025	FNY Investment Advisers LLC	1,000	$26K	0.0%	N/A	0.002%
12/2/2025	IFP Advisors Inc	1,369	$36K	0.0%	-32.7%	0.003%
11/19/2025	Danske Bank A S	23,043	$0.61M	0.0%	N/A	0.050%
11/17/2025	Voloridge Investment Management LLC	292,443	$7.79M	0.0%	-10.2%	0.636%
11/17/2025	Susquehanna Fundamental Investments LLC	12,568	$0.34M	0.0%	-87.6%	0.027%

Data available starting January 2016

Amphastar Pharmaceuticals, Inc., a bio-pharmaceutical company, develops, manufactures, markets, and sells generic and proprietary injectable, inhalation, and intranasal products in the United States, China, and France. It offers BAQSIMI, a nasal spray for the treatment of severe hypoglycemia; Primatene Mist, an over-the-counter epinephrine inhalation product for the temporary relief of mild symptoms of intermittent asthma; Enoxaparin, to prevent and treat deep vein thrombosis; REXTOVY and Naloxone for opioid overdose; Glucagon for injection emergency kit; and Cortrosyn, for use as a diagnostic agent in the screening of patients with adrenocortical insufficiency. The company provides Amphadase, an injection to absorb and disperse other injected drugs; Epinephrine injection for allergic reactions; Lidocaine jelly, an anesthetic product for urological procedures; Lidocaine topical solution for various procedures; Phytonadione injection, a vitamin K1 injection for newborn babies; emergency syringe products; morphine injection for use with patient-controlled analgesia pumps; and Lorazepam injection for surgery and medical procedures. In addition, it offers Neostigmine methylsulfate injection to treat myasthenia gravis and to reverse the effects of muscle relaxants; Isoproterenol hydrochloride injection for mild or transient episodes of heart block; Ganirelix Acetate injection for the inhibition of premature luteinizing hormone surges; Vasopressin to increase blood pressure; and Regadenoson, a stress agent for radionuclide myocardial perfusion imaging. Further, the company distributes recombinant human insulin APIs and porcine insulin API. Additionally, it develops generic product candidates, such as injectable, inhalation, and analytical technologies; biosimial product candidates; and intranasal epinephrine for the treatment of allergic reactions. The company was founded in 1996 and is headquartered in Rancho Cucamonga, California.

Today's Range

Now: $19.50

$19.77

50 Day Range

MA: $24.27

$18.17

$29.26

52 Week Range

Now: $19.50

$17.03

$31.26

Volume

1,714 shs

Average Volume

475,524 shs

Market Capitalization

$884.67 million

P/E Ratio

9.59

Dividend Yield

N/A

Beta

0.93

Who are the company insiders with the largest holdings of Amphastar Pharmaceuticals?: Amphastar Pharmaceuticals' top insider shareholders include:
Physics & Chemistry La Applied (Major Shareholder)
Jack Y Zhang (CEO)
Mary Z Luo (COO)
Richard Koo (Director)
Jason B Shandell (Insider)
Jason B Shandell (Director)
Jason B Shandell (President)
Jason B Shandell (General Counsel)
Howard Lee (Director)
Richard K Prins (Director)
Learn More about top insider investors at Amphastar Pharmaceuticals.
Who are the major institutional investors of Amphastar Pharmaceuticals?: Amphastar Pharmaceuticals' top institutional shareholders include:
Vanguard Group Inc. — 5.68%
TD Asset Management Inc — 4.27%
Dimensional Fund Advisors LP — 3.92%
State Street Corp — 3.33%
Fuller & Thaler Asset Management Inc. — 3.03%
Fuller & Thaler Asset Management Inc. — 3.03%
Learn More about top institutional investors of Amphastar Pharmaceuticals stock.
Which institutional investors are selling Amphastar Pharmaceuticals stock?: During the previous quarter, AMPH stock was sold by these institutional investors:
Millennium Management LLC
Price T Rowe Associates Inc. MD
Boston Trust Walden Corp
Balyasny Asset Management L.P.
Voloridge Investment Management LLC
UBS Group AG
Renaissance Technologies LLC
Geode Capital Management LLC
In the last year, company insiders that have sold Amphastar Pharmaceuticals company stock include:
Physics & Chemistry La Applied (Major Shareholder)
Jack Y Zhang (CEO)
Mary Z Luo (COO)
Learn More investors selling Amphastar Pharmaceuticals stock.
Which institutional investors are buying Amphastar Pharmaceuticals stock?: During the last quarter, AMPH stock was bought by institutional investors including:
Marshall Wace LLP
Pacer Advisors Inc.
Trexquant Investment LP
Invesco Ltd.
Brandywine Global Investment Management LLC
Bridge City Capital LLC
SG Americas Securities LLC
Denali Advisors LLC