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Amphastar Pharmaceuticals

241 hedge funds and large institutions have $964M invested in Amphastar Pharmaceuticals in 2025 Q1 according to their latest regulatory filings, with 32 funds opening new positions, 80 increasing their positions, 95 reducing their positions, and 50 closing their positions.

New
Increased
Maintained
Reduced
Closed

90% more call options, than puts

Call options by funds: $637K | Put options by funds: $336K

3.39% less ownership

Funds ownership: 73.14%69.75% (-3.4%)

8% less funds holding

Funds holding: 263241 (-22)

16% less repeat investments, than reductions

Existing positions increased: 80 | Existing positions reduced: 95

26% less capital invested

Capital invested by funds: $1.31B → $964M (-$342M)

36% less first-time investments, than exits

New positions opened: 32 | Existing positions closed: 50

100% less funds holding in top 10

Funds holding in top 10: 10 (-1)

Holders
241
Holders Change
-22
Holders Change %
-8.37%
% of All Funds
3.23%
Holding in Top 10
Holding in Top 10 Change
-1
Holding in Top 10 Change %
-100%
% of All Funds
New
32
Increased
80
Reduced
95
Closed
50
Calls
$637K
Puts
$336K
Net Calls
+$301K
Net Calls Change
-$398K

AMPH Hedge Fund Activity: Q1 2025 in Review

241 of the 7,457 institutional investors tracked by Wall St. Rank reported a position in Amphastar Pharmaceuticals (AMPH) for Q1 2025, worth a combined $964M — down 26% from $1.31B a quarter earlier.

Sellers outnumbered buyers: 50 funds closed out of AMPH and 32 opened new positions — a net loss of 18 holders — while 95 trimmed existing stakes and 80 added.

The largest buyer was Millennium Management, adding an estimated $19.5M. The largest seller was Neuberger Berman Group, exiting entirely with an estimated $51M sold.

  • 241 institutional investors held Amphastar Pharmaceuticals (AMPH) as of Q1 2025, down from 263 in Q4 2024.
  • Funds reported $964M of Amphastar Pharmaceuticals stock for Q1 2025, down 26% quarter-over-quarter.
  • 32 funds opened new Amphastar Pharmaceuticals positions in Q1 2025 and 50 closed out, a net change of -18 holders.
  • The largest Amphastar Pharmaceuticals buyer in Q1 2025 was Millennium Management, an estimated $19.5M added.
  • The largest Amphastar Pharmaceuticals seller in Q1 2025 was Neuberger Berman Group, an estimated $51M sold.

Based on aggregated 13F filings for Q1 2025.