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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.

Open-market trades, last 90 days

Open-market purchases (P) and sales (S) by Amphastar Pharmaceuticals, Inc. insiders, counted by Form 4 filing. Trades with a flagged price and duplicate filings are left out.

Open-market buys
0 filings
Open-market sells
5 filings
3 insiders, $763.9K in total
Insiders trading
3
Net value
−$763.9K
Purchases minus sales

Insider roster

Directors, officers and 10% owners who have filed a Form 4 for Amphastar Pharmaceuticals, Inc., current and former, most recent filer first. Last reported holding is the position after the last non-derivative trade in their latest filing.

Insider roster for Amphastar Pharmaceuticals, Inc.
NameTitleLast reported holdingLast filingFilings, past year
Peters William JCFO, EVP & TREASURER168,707Sep 23, 20266
Zhou RongSENIOR EVP, PRODUCTION CENTER169,203Sep 17, 20267
Prins Richard KDirector29,625Aug 12, 20263
Pierce Anthony TDirector7,886Jul 13, 20261
Zasloff Michael ADirector37,667Jun 3, 20261
Lee HowardDirector159,350Jun 3, 20261
Gerst Diane G.Director31,899Jun 3, 20261
Deflin GayleDirector19,057Jun 3, 20261
Gaugh David RussellDirector14,447Jun 3, 20261
Luo Mary Z.COO, Chief Scientist, Chairman1,245,125IndirectMar 17, 20264
Zhang Jack Y.CEO & CHIEF SCIENTIFIC OFFICER1,245,125IndirectMar 17, 20264
Liawatidewi YakobEVP CORP ADMIN CENTER121,892Mar 17, 20264
Petersen Floyd F.Director71,368Dec 15, 20254

Insider trades

Each row adds up one type of transaction in one Form 4 filing. Only open-market purchases (P) and sales (S) are shown by default; use the filters to see grants, option exercises and other codes.

Insider trades
Filed (ET)Trade dateFiling delayInsiderTransactionSharesAvg priceValueHolding changeFlags
Sep 8, 2023 (view filing)Sep 62 daysPeters William JCFO, EVP & TreasurerSSale−60.7K$51.75−$3.14M−37.5%101.4K after2 lots10b5-1
Aug 29, 2023 (view filing)Aug 281 dayLiawatidewi YakobEVP Corp Admin CenterSSale−28.8K$53.13−$1.53M−29.3%69.7K after
Aug 21, 2023 (view filing)Aug 183 daysPrins Richard KDirectorSSale−2.00K$52.50−$105.0K−4.7%40.9K after
Aug 16, 2023 (view filing)Aug 151 dayZasloff Michael ADirectorSSale−12.8K$57.22−$730.1K−27.4%33.8K after
Aug 16, 2023 (view filing)Aug 151 dayPrins Richard KDirectorSSale−4.16K$57.39−$238.9K−8.8%42.9K after
Jun 20, 2023 (view filing)Jun 155 daysZhou RongEVP, Production CenterSSale−5.00K$51.79−$258.9K−4.9%96.9K after
Jun 20, 2023 (view filing)Jun 155 daysPeters William JCFO, EVP & TreasurerSSale−36.9K$50.85−$1.87M−25.9%105.6K after3 lots10b5-1
Jun 14, 2023 (view filing)Jun 131 dayZhou RongEVP, Production CenterSSale−5.00K$48.24−$241.2K−5.4%88.3K after
Jun 5, 2023 (view filing)Jun 23 daysPeters William JCFO, EVP & TreasurerSSale−11.0K$46.35−$509.9K−9.4%105.6K after10b5-1
Jun 5, 2023 (view filing)Jun 14 daysLee HowardDirectorSSale−16.7K$45.02−$750.9K−10.4%142.9K after
May 22, 2023 (view filing)May 184 daysPeters William JCFO, EVP & TreasurerSSale−10.5K$44.35−$465.7K−9.1%105.1K after10b5-1
May 19, 2023 (view filing)May 181 dayZhou RongEVP, Production CenterSSale−10.0K$44.21−$442.1K−10.2%87.6K after
May 19, 2023 (view filing)May 181 dayDeflin GayleDirectorSSale−4.52K$44.01−$198.9K−52.1%4.16K after
May 18, 2023 (view filing)May 171 dayPetersen Floyd F.DirectorSSale−5.00K$43.13−$215.7K−5.9%80.1K after
May 17, 2023 (view filing)May 152 daysDeflin GayleDirectorSSale−1.50K$43.15−$64.7K−14.7%8.68K after
May 16, 2023 (view filing)May 151 dayZasloff Michael ADirectorSSale−7.50K$42.18−$316.4K−14.6%43.9K after
May 16, 2023 (view filing)May 12-154 daysPrins Richard KDirectorSSale−10.0K$42.78−$427.8K−18.4%44.3K after2 lots
Apr 18, 2023 (view filing)Apr 171 dayPeters William JCFO, EVP & TreasurerSSale−5.63K$42.35−$238.5K−5.1%105.1K after10b5-1
Apr 14, 2023 (view filing)Apr 131 dayLiawatidewi YakobEVP Corp Admin CenterSSale−11.5K$41.56−$477.7K−14.2%69.2K after2 lots10b5-1
Apr 14, 2023 (view filing)Apr 131 dayPeters William JCFO, EVP & TreasurerSSale−4.87K$42.35−$206.2K−4.4%105.1K after10b5-1
Apr 12, 2023 (view filing)Apr 102 daysLiawatidewi YakobEVP Corp Admin CenterSSale−5.00K$40.00−$200.0K−6.7%69.2K after
Apr 12, 2023 (view filing)Apr 102 daysPeters William JCFO, EVP & TreasurerSSale−10.0K$40.35−$404.8K−8.7%105.1K after
Apr 4, 2023 (view filing)Apr 31 dayPetersen Floyd F.DirectorSSale−491$37.72−$18.5K−0.6%85.1K after10b5-1
Mar 17, 2023 (view filing)Mar 152 daysPeters William JCFO, EVP & TreasurerSSale−12.8K$36.43−$465.4K−9.7%118.5K after
Mar 3, 2023 (view filing)Mar 12 daysPeters William JCFO, EVP & TreasurerSSale−11.0K$36.33−$398.7K−9.8%100.6K after
Mar 2, 2023 (view filing)Mar 11 dayPetersen Floyd F.DirectorSSale−500$36.70−$18.3K−0.6%85.6K after3 lots
Feb 2, 2023 (view filing)Feb 11 dayPetersen Floyd F.DirectorSSale−500$30.35−$15.2K−0.6%86.1K after
Jan 4, 2023 (view filing)Jan 31 dayPetersen Floyd F.DirectorSSale−500$27.94−$14.0K−0.6%86.6K after
Dec 2, 2022 (view filing)Dec 11 dayPetersen Floyd F.DirectorSSale−500$30.13−$15.1K−0.6%87.1K after
Nov 2, 2022 (view filing)Nov 11 dayPetersen Floyd F.DirectorSSale−500$31.13−$15.6K−0.6%87.6K after
Oct 4, 2022 (view filing)Oct 31 dayPetersen Floyd F.DirectorSSale−500$28.59−$14.3K−0.6%88.1K after
Sep 2, 2022 (view filing)Sep 11 dayPetersen Floyd F.DirectorSSale−500$29.44−$14.7K−0.6%88.6K after
Aug 10, 2022 (view filing)Aug 91 dayPeters William JCFO, EVP & TreasurerSSale−10.0K$38.35−$383.5K−9.1%100.5K after
Aug 10, 2022 (view filing)Aug 8-92 daysLiawatidewi YakobEVP Corp Admin CenterSSale−8.05K$38.38−$309.1K−11.6%61.6K after2 lots
Aug 2, 2022 (view filing)Aug 11 dayPetersen Floyd F.DirectorSSale−500$37.48−$18.7K−0.6%89.1K after
Jul 19, 2022 (view filing)Jul 181 dayGerst Diane G.DirectorSSale−1.52K$37.23−$56.6K−10.6%12.8K after
Jul 18, 2022 (view filing)Jul 153 daysLiawatidewi YakobEVP Corp Admin CenterSSale−10.8K$36.64−$397.1K−15.0%61.6K after2 lots
Jul 12, 2022 (view filing)Jul 111 dayGerst Diane G.DirectorSSale−1.52K$36.26−$55.2K−10.6%12.8K after
Jul 6, 2022 (view filing)Jul 51 dayGerst Diane G.DirectorSSale−1.81K$35.00−$63.5K−12.4%12.8K after
Jul 5, 2022 (view filing)Jul 14 daysPetersen Floyd F.DirectorSSale−500$34.78−$17.4K−0.6%89.6K after
Jul 5, 2022 (view filing)Jun 305 daysGerst Diane G.DirectorSSale−5.15K$35.00−$180.1K−28.6%12.8K after
Jul 1, 2022 (view filing)Jun 301 dayPeters William JCFO, EVP & TreasurerSSale−18.4K$34.95−$642.6K−15.5%100.5K after
Jun 22, 2022 (view filing)Jun 175 daysPeters William JCFO, EVP & TreasurerSSale−5.51K$32.05−$176.7K−5.2%100.5K after
Jun 7, 2022 (view filing)Jun 61 dayLee HowardDirectorSSale−10.3K$37.79−$388.9K−6.9%138.8K after
Jun 2, 2022 (view filing)Jun 11 dayPetersen Floyd F.DirectorSSale−500$37.00−$18.5K−0.6%85.9K after2 lots
May 25, 2022 (view filing)May 232 daysLee HowardDirectorSSale−10.0K$34.93−$349.3K−6.7%138.8K after
May 23, 2022 (view filing)4:05 PM ETMay 203 daysLuo Mary Z. and 1 otherCEO & Chief Scientific OfficerSSale−10.7K$34.21−$364.4K−0.5%2.10M after
May 20, 2022 (view filing)4:38 PM ETMay 18-192 daysLuo Mary Z. and 1 otherCEO & Chief Scientific OfficerSSale−108.8K$34.00−$3.70M−4.9%2.11M after5 lots
May 19, 2022 (view filing)May 181 dayPetersen Floyd F.DirectorSSale−9.92K$35.05−$347.8K−10.3%86.4K after
May 18, 2022 (view filing)4:06 PM ETMay 16-172 daysLuo Mary Z. and 1 otherCEO & Chief Scientific OfficerSSale−118.4K$35.75−$4.23M−5.1%2.22M after4 lots