Skip to main content

Amphastar Pharmaceuticals, Inc.

AMPH
Exchange
Nasdaq
Industry
Pharmaceutical Preparations
SEC CIK
0001297184

In the last 90 days, Amphastar Pharmaceuticals, Inc. insiders filed 0 open-market purchases and 5 sales; 212 institutions reported holding it in 13F filings for Q2 2026, worth $572.1M in total; no superinvestor holds it.

13F holders, Q1 2026

Institutional positions in Amphastar Pharmaceuticals, Inc. as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works

Institutional holders
215
−16 vs. Q4 2025
Shares held
32.3M
+1.49M (+4.8%) vs. Q4 2025
Total value
$634.0M
−$192.7M (−23.3%) vs. Q4 2025
New holders
29
69 more added
Sold out
45
95 more reduced

5 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.

Compare with Q4 2025: new holders, sold out and not filed yet

Holders and value by quarter

Institutions reporting AMPH on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.

Institutional holdersQ1 2026: 215 institutions
Q1 2021: 135 institutionsQ2 2021: 146 institutionsQ3 2021: 140 institutionsQ4 2021: 168 institutionsQ1 2022: 203 institutionsQ2 2022: 223 institutionsQ3 2022: 207 institutionsQ4 2022: 213 institutionsQ1 2023: 218 institutionsQ2 2023: 246 institutionsQ3 2023: 256 institutionsQ4 2023: 276 institutionsQ1 2024: 271 institutionsQ2 2024: 269 institutionsQ3 2024: 279 institutionsQ4 2024: 264 institutionsQ1 2025: 241 institutionsQ2 2025: 245 institutionsQ3 2025: 243 institutionsQ4 2025: 236 institutionsQ1 2026: 215 institutionsQ2 2026: 212 institutions
Value heldQ1 2026: $634.0M
Q1 2021: $476.9MQ2 2021: $549.6MQ3 2021: $530.8MQ4 2021: $678.8MQ1 2022: $1.07BQ2 2022: $1.06BQ3 2022: $839.3MQ4 2022: $816.7MQ1 2023: $1.13BQ2 2023: $1.80BQ3 2023: $1.47BQ4 2023: $2.06BQ1 2024: $1.47BQ2 2024: $1.37BQ3 2024: $1.72BQ4 2024: $1.31BQ1 2025: $963.6MQ2 2025: $752.0MQ3 2025: $872.8MQ4 2025: $899.7MQ1 2026: $634.0MQ2 2026: $572.1M
Institutions holding AMPH and their total value by quarter
QuarterHoldersValue
Q2 2026212$572.1M
Q1 2026215$634.0M
Q4 2025236$899.7M
Q3 2025243$872.8M
Q2 2025245$752.0M
Q1 2025241$963.6M
Q4 2024264$1.31B
Q3 2024279$1.72B
Q2 2024269$1.37B
Q1 2024271$1.47B
Q4 2023276$2.06B
Q3 2023256$1.47B
Q2 2023246$1.80B
Q1 2023218$1.13B
Q4 2022213$816.7M
Q3 2022207$839.3M
Q2 2022223$1.06B
Q1 2022203$1.07B
Q4 2021168$678.8M
Q3 2021140$530.8M
Q2 2021146$549.6M
Q1 2021135$476.9M

Institutions, Q1 2026

Shares, value and share of portfolio for each institution holding Amphastar Pharmaceuticals, Inc.; share changes are against Q4 2025.

Institutions holding AMPH in Q1 2026
InstitutionSharesValue% of portfolioChange in sharesAction
BlackRock, Inc.5,421,343$106.2M0.00%−40,672−0.7%Reduced
Dimensional Fund Advisors LP2,027,947$39.7M0.01%+228,262+12.7%Added
State Street Corp1,607,515$31.5M0.00%+75,729+4.9%Added
Vanguard Capital Management LLC1,543,655$30.2M0.00%+1,543,655New
TD Asset Management Inc1,541,044$30.2M0.02%−422,008−21.5%Reduced
Fuller & Thaler Asset Management, Inc.1,395,139$27.3M0.09%+6760.0%Added
Marshall Wace, LLP1,025,640$20.1M0.02%−211,644−17.1%Reduced
American Century Companies Inc1,017,538$19.9M0.01%+352,202+52.9%Added
Geode Capital Management, LLC976,650$19.1M0.00%+89,825+10.1%Added
Boston Trust Walden Corp944,789$18.5M0.15%−142,477−13.1%Reduced
Epoch Investment Partners, Inc.898,895$17.6M0.11%−227,690−20.2%Reduced
Vanguard Portfolio Management LLC787,816$15.4M0.00%+787,816New
D. E. Shaw & Co., Inc.665,542$13.0M0.01%+108,476+19.5%Added
LSV Asset Management651,714$12.8M0.03%+541,414+490.9%Added
Invesco Ltd.604,774$11.8M0.00%+103,370+20.6%Added
Renaissance Technologies LLC553,900$10.9M0.02%+9,200+1.7%Added
Systematic Financial Management LP452,898$8.87M0.20%+17,318+4.0%Added
Morgan Stanley420,337$8.23M0.00%−171,294−29.0%Reduced
UBS Group AG420,263$8.23M0.00%+163,639+63.8%Added
Royce & Associates LP406,175$7.96M0.08%+53,878+15.3%Added
Northern Trust Corp372,279$7.29M0.00%+888+0.2%Added
Millennium Management LLC371,373$7.28M0.01%+80,700+27.8%Added
Bridge City Capital, LLC335,105$6.56M1.82%+99,620+42.3%Added
Bridgeway Capital Management, LLC330,457$6.47M0.13%+6,908+2.1%Added
Goldman Sachs Group Inc329,388$6.45M0.00%−227,321−40.8%Reduced
Arrowstreet Capital, Limited Partnership325,291$6.37M0.00%−234,135−41.9%Reduced
Charles Schwab Investment Management Inc321,039$6.29M0.00%−29,668−8.5%Reduced
Denali Advisors LLC266,465$5.22M0.58%+54,700+25.8%Added
Pacer Advisors, Inc.261,483$5.12M0.01%+83,739+47.1%Added
Victory Capital Management Inc249,617$4.89M0.00%−55,544−18.2%Reduced
Bank of New York Mellon Corp243,226$4.76M0.00%−15,835−6.1%Reduced
Vanguard Fiduciary Trust Co231,044$4.53M0.00%+231,044New
Principal Financial Group Inc209,131$4.10M0.00%−8,843−4.1%Reduced
Rice Hall James & Associates, LLC187,348$3.67M0.20%+66,172+54.6%Added
Empowered Funds, LLC181,332$3.55M0.02%+15,425+9.3%Added
Bank of America Corp174,323$3.41M0.00%+46,149+36.0%Added
Voloridge Investment Management, LLC171,188$3.35M0.01%−60,117−26.0%Reduced
BNP Paribas Arbitrage, SA156,077$3.06M0.00%+35,184+29.1%Added
First Trust Advisors LP150,591$2.95M0.00%+10,281+7.3%Added
New York State Common Retirement Fund148,722$2.91M0.00%+22,754+18.1%Added
Universal- Beteiligungs- und Servicegesellschaft mbH139,402$2.73M0.00%+110,298+379.0%Added
Franklin Resources Inc139,305$2.73M0.00%+113,260+434.9%Added
Two Sigma Investments, LP138,148$2.71M0.00%+39,470+40.0%Added
Lam Group, Inc.130,800$2.56M1.41%00.0%Unchanged
Public Sector Pension Investment Board126,574$2.48M0.01%+4,069+3.3%Added
Nordea Investment Management AB123,824$2.42M0.00%−5,320−4.1%Reduced
Bessemer Group Inc122,046$2.39M0.00%+1,156+1.0%Added
O'Shaughnessy Asset Management, LLC103,929$2.04M0.01%+16,746+19.2%Added
JPMorgan Chase & Co104,574$2.01M0.00%−54,070−34.1%Reduced
Jane Street Group, LLC92,475$1.81M0.00%−125,062−57.5%Reduced
XTX Topco Ltd87,736$1.72M0.03%+39,129+80.5%Added
Rhumbline Advisers83,721$1.64M0.00%+1,331+1.6%Added
Exchange Traded Concepts, LLC82,416$1.61M0.01%+72,998+775.1%Added
Legal & General Group Plc80,916$1.59M0.00%−9,814−10.8%Reduced
AQR Capital Management LLC78,778$1.54M0.00%+11,126+16.4%Added
Ameriprise Financial Inc78,775$1.54M0.00%−54,940−41.1%Reduced
Alliancebernstein L.P.56,430$1.51M0.00%−4,200−6.9%Reduced
Nuveen, LLC76,595$1.50M0.00%+494+0.6%Added
Swiss National Bank72,600$1.42M0.00%00.0%Unchanged
Robeco Institutional Asset Management B.V.66,407$1.30M0.00%+66,407New
Citadel Advisors LLC65,540$1.28M0.00%−163,184−71.3%Reduced
Hussman Strategic Advisors, Inc.63,000$1.23M0.27%+63,000New
Algert Global LLC62,360$1.22M0.02%−62,770−50.2%Reduced
HRT Financial LP56,181$1.10M0.00%+56,181New
UBS Asset Management Americas Inc55,375$1.08M0.00%+143+0.3%Added
Assetmark, Inc53,738$1.05M0.00%−621−1.1%Reduced
Prudential Financial Inc50,693$993.1K0.00%+3,490+7.4%Added
Vanguard Global Advisers, LLC50,163$982.7K0.00%+50,163New
Steel Peak Wealth Management LLC48,462$949.4K0.03%−7,233−13.0%Reduced
Trexquant Investment LP47,867$937.7K0.01%−65,806−57.9%Reduced
Price T Rowe Associates Inc44,903$880.0K0.00%+8,107+22.0%Added
Polaris Capital Management, LLC43,232$846.9K0.07%+7,700+21.7%Added
Wells Fargo & Company42,019$823.1K0.00%−3,283−7.2%Reduced
HSBC Holdings PLC38,017$753.5K0.00%+38,017New
Man Group plc37,274$730.2K0.00%+23,123+163.4%Added
Citigroup Inc35,904$703.4K0.00%+7,624+27.0%Added
Legato Capital Management LLC34,135$668.7K0.06%+7,545+28.4%Added
Segall Bryant & Hamill, LLC33,318$652.7K0.01%+22,133+197.9%Added
Deutsche Bank AG33,131$649.0K0.00%+3,574+12.1%Added
SG Americas Securities, LLC32,806$643.0K0.00%−60,709−64.9%Reduced
SummerHaven Investment Management, LLC32,633$639.3K0.39%−5,567−14.6%Reduced
Quadrature Capital Ltd30,561$598.7K0.01%+30,561New
Great West Life Assurance Co30,216$593.0K0.00%00.0%Unchanged
Freestone Grove Partners LP29,857$584.9K0.00%+2,264+8.2%Added
Squarepoint Ops LLC28,345$555.3K0.00%+13,485+90.7%Added
California State Teachers Retirement System28,299$554.4K0.00%−7,499−20.9%Reduced
Illumine Investment Management, LLC28,078$550.0K0.42%−250−0.9%Reduced
State of Alaska, Department of Revenue27,410$536.0K0.01%−506−1.8%Reduced
Advisor OS, LLC25,405$497.7K0.04%00.0%Unchanged
Advisory Research Inc25,335$496.3K0.06%+10,174+67.1%Added
Intech Investment Management LLC24,207$474.2K0.00%−39,025−61.7%Reduced
Thrivent Financial for Lutherans23,618$463.0K0.00%−695−2.9%Reduced
Vident Advisory, LLC23,244$455.4K0.00%+2,835+13.9%Added
Vanguard Asset Management, Ltd23,052$451.6K0.00%+23,052New
New York State Teachers Retirement System21,825$428.0K0.00%−1,152−5.0%Reduced
Barclays PLC21,283$416.9K0.00%−54,036−71.7%Reduced
MetLife Investment Management20,761$406.7K0.00%−314−1.5%Reduced
Round Rock Advisors, LLC20,495$401.5K0.06%+18+0.1%Added
Illinois Municipal Retirement Fund19,528$382.6K0.00%−1,385−6.6%Reduced
Raymond James Financial Inc19,055$373.3K0.00%−65,399−77.4%Reduced