Polaris Capital Management’s Amphastar Pharmaceuticals AMPH Stock Holding History

Polaris Capital Management’s Portfolio AMPH Stock Details AMPH Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	$872K	Hold	43,232	–	–	0.08%	82
2026 Q1	$847K	Buy	43,232 +7,700	+22%	+$188K	0.07%	79
2025 Q4	$952K	Buy	35,532 +22,432	+171%	+$578K	0.08%	80
2025 Q3	$349K	Sell	13,100 -22,000	-63%	-$568K	0.02%	89
2025 Q2	$806K	Buy	35,100 +4,300	+14%	+$107K	0.05%	89
2025 Q1	$893K	Buy	30,800 +6,300	+26%	+$201K	0.05%	83
2024 Q4	$910K	Buy	+24,500	New	+$1.12M	0.04%	90

Other funds holding AMPH

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Dimensional Fund Advisors Austin, Texas $552B AUM 44.19% 1-Year Est. Return

State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

American Century Companies Kansas City, Missouri $226B AUM 44.75% 1-Year Est. Return

Marshall Wace London, United Kingdom $127B AUM 46.06% 1-Year Est. Return

Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return

Fuller & Thaler Asset Management San Mateo, California $36.7B AUM 74.15% 1-Year Est. Return

D.E. Shaw & Co New York $210B AUM 57.28% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

Polaris Capital Management's AMPH Position: Q2 2026 in Review

Polaris Capital Management held its Amphastar Pharmaceuticals (AMPH) position steady in Q2 2026 at 43,232 shares worth $872K. The position accounts for 0.08% of the portfolio, ranked #82.

Polaris Capital Management first reported a position in AMPH in Q4 2024 and has held it in 7 quarters since. The position peaked at $952K in Q4 2025. 210 funds tracked by Wall St. Rank hold AMPH as of Q2 2026.

Polaris Capital Management held 43,232 shares of Amphastar Pharmaceuticals worth $872K as of Q2 2026.
Polaris Capital Management left its Amphastar Pharmaceuticals share count unchanged in Q2 2026.
Amphastar Pharmaceuticals made up 0.08% of Polaris Capital Management's portfolio in Q2 2026, its #82 holding.
Polaris Capital Management first reported a position in Amphastar Pharmaceuticals in Q4 2024 and has held it in 7 quarters since.
Polaris Capital Management's Amphastar Pharmaceuticals position peaked at $952K in Q4 2025.
210 funds tracked by Wall St. Rank held Amphastar Pharmaceuticals as of Q2 2026.

Based on Polaris Capital Management's 13F filing for Q2 2026, filed 27 Jul 2026.