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SCHEDULE 13G Filed 2026-07-14 Event — SEC 0000354204-26-000782 →

DIMENSIONAL FUND ADVISORS LP → Amphastar Pharmaceuticals Inc AMPH

Stake: — Shares: — Class: Common Stock

Item 4 — Purpose of Transaction

Not extracted from this filing — typically because it's an amendment (13D/A) and Item 4 is unchanged from the parent filing. Read the raw SEC filing →

Cross-References

Insider Activity (last 365d)
2 transactions
2 buys · 0 sales · 0 awards/exercises
Issuer Cluster
1 13D/G filings on this issuer
0 other filings besides this one
Filer Track Record
78 filings by this filer
77 other filings in the data moat
Short Interest · settle 2026-09-30
DTC 7.10
4,405,038 shares short · -11.8% vs prior

Form 4 Insider Transactions · last 365d

DateInsiderRoleTypeSharesPriceValue
2026-07-09 Pierce Anthony T director Award 7,886 — —
2026-07-09 Pierce Anthony T director Award 16,646 $19.02 $317K

Other Filings by DIMENSIONAL FUND ADVISORS LP

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2026-10-08 SCHEDULE 13G Bloomin' Brands Inc — — view →
2026-10-08 SCHEDULE 13G Civista Bancshares Inc — — view →
2026-10-08 SCHEDULE 13G Columbia Sportswear Co — — view →
2026-10-08 SCHEDULE 13G Community West Bancshares — — view →
2026-10-08 SCHEDULE 13G Crescent Energy Co — — view →
2026-10-08 SCHEDULE 13G Universal Health Services Inc — — view →
2026-10-08 SCHEDULE 13G National Bank Holdings Corp — — view →
2026-10-08 SCHEDULE 13G Orrstown Financial Services Inc — — view →
2026-10-08 SCHEDULE 13G National Vision Holdings Inc — — view →
2026-10-08 SCHEDULE 13G Encore Capital Group Inc — — view →
2026-10-08 SCHEDULE 13G Howard Hughes Holdings Inc — — view →
2026-10-08 SCHEDULE 13G Shenandoah Telecommunications Co — — view →
2026-10-08 SCHEDULE 13G Patrick Industries Inc — — view →
2026-10-08 SCHEDULE 13G Sonoco Products Co — — view →
2026-10-08 SCHEDULE 13G Virtus Investment Partners Inc — — view →
Showing 20 of 77

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