Portolan Capital Management’s Amphastar Pharmaceuticals AMPH Stock Holding History

Portolan 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
2025 Q1	–	Sell	-131,123	Closed	-$4.87M	–	113
2024 Q4	$4.87M	Sell	131,123 -196,641	-60%	-$8.99M	0.33%	92
2024 Q3	$15.9M	Buy	327,764 +218,901	+201%	+$9.61M	1.15%	23
2024 Q2	$4.35M	Buy	108,863 +17,858	+20%	+$740K	0.36%	92
2024 Q1	$4M	Sell	91,005 -57,411	-39%	-$2.97M	0.3%	94
2023 Q4	$9.18M	Buy	148,416 +15,566	+12%	+$818K	0.8%	44
2023 Q3	$6.11M	Sell	132,850 -49,393	-27%	-$2.69M	0.57%	58
2023 Q2	$10.5M	Sell	182,243 -158,350	-46%	-$7.02M	0.93%	31
2023 Q1	$12.8M	Buy	340,593 +69,802	+26%	+$2.29M	1.22%	23
2022 Q4	$7.59M	Sell	270,791 -11,396	-4%	-$331K	0.75%	47
2022 Q3	$7.93M	Buy	282,187 +7,298	+3%	+$238K	0.84%	40
2022 Q2	$9.56M	Buy	+274,889	New	+$9.81M	0.96%	39

Other funds holding AMPH

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

Vanguard Group Malvern, Pennsylvania $6.9T AUM 27.45% 1-Year Est. Return

TD Asset Management Toronto, Ontario, Canada $115B AUM 41.58% 1-Year Est. Return

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

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

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

EIP

Epoch Investment Partners New York $17.6B AUM 34.17% 1-Year Est. Return

BTW

Boston Trust Walden Boston, Massachusetts $13.1B AUM 24.63% 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

Portolan Capital Management's AMPH Position: Q1 2025 in Review

Portolan Capital Management sold out of Amphastar Pharmaceuticals (AMPH) in Q1 2025, closing a stake of 131,123 shares — an estimated $4.87M sold.

Portolan Capital Management first reported a position in AMPH in Q2 2022 and held it in 11 quarters. The position peaked at $15.9M in Q3 2024. 241 funds tracked by Wall St. Rank hold AMPH as of Q1 2025.

Portolan Capital Management reported no remaining Amphastar Pharmaceuticals position as of Q1 2025 after selling out during the quarter.
Portolan Capital Management sold 131,123 Amphastar Pharmaceuticals shares in Q1 2025, an estimated $4.87M.
Portolan Capital Management first reported a position in Amphastar Pharmaceuticals in Q2 2022 and held it in 11 quarters.
Portolan Capital Management's Amphastar Pharmaceuticals position peaked at $15.9M in Q3 2024.
241 funds tracked by Wall St. Rank held Amphastar Pharmaceuticals as of Q1 2025.

Based on Portolan Capital Management's 13F filing for Q1 2025, filed 15 May 2025.