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Prothena Corp

181 hedge funds and large institutions have $452M invested in Prothena Corp in 2025 Q4 according to their latest regulatory filings, with 25 funds opening new positions, 62 increasing their positions, 57 reducing their positions, and 26 closing their positions.

New
Increased
Maintained
Reduced
Closed

8.64% more ownership

Funds ownership: 79.15%87.78% (+8.6%)

9% more capital invested

Capital invested by funds: $416M → $452M (+$35.8M)

9% more repeat investments, than reductions

Existing positions increased: 62 | Existing positions reduced: 57

4% less first-time investments, than exits

New positions opened: 25 | Existing positions closed: 26

3% less funds holding

Funds holding: 187181 (-6)

16% less call options, than puts

Call options by funds: $6.74M | Put options by funds: $8.02M

50% less funds holding in top 10

Funds holding in top 10: 21 (-1)

Holders
181
Holders Change
-6
Holders Change %
-3.21%
% of All Funds
2.2%
Holding in Top 10
1
Holding in Top 10 Change
-1
Holding in Top 10 Change %
-50%
% of All Funds
0.01%
New
25
Increased
62
Reduced
57
Closed
26
Calls
$6.74M
Puts
$8.02M
Net Calls
-$1.28M
Net Calls Change
+$6.27M
Name Holding Trade Value Shares
Change
Change in
Stake
Fidelity Investments
1
Fidelity Investments
Massachusetts
$72.1M -$3.56M -350,000 -4%
BlackRock
2
BlackRock
New York
$39.2M +$5.18M +509,042 +14%
RCMNY
3
Rubric Capital Management (New York)
New York
$35.1M +$21.8M +2,136,958 +139%
State Street
4
State Street
Massachusetts
$21.7M +$13.9M +1,366,764 +152%
Vanguard Group
5
Vanguard Group
Pennsylvania
$20.4M +$927K +91,060 +4%
D.E. Shaw & Co
6
D.E. Shaw & Co
New York
$16.1M +$3.73M +365,951 +28%
AC
7
Armistice Capital
New York
$14.3M -$3.3M -324,000 -18%
ACM
8
ADAR1 Capital Management
Texas
$13.9M -$115K -11,334 -0.8%
Acadian Asset Management
9
Acadian Asset Management
Massachusetts
$13.7M +$2.02M +198,116 +16%
PAI
10
Palo Alto Investors
California
$12.6M -$35.8K -3,518 -0.3%
Morgan Stanley
11
Morgan Stanley
New York
$11.9M +$4.55M +447,101 +56%
Geode Capital Management
12
Geode Capital Management
Massachusetts
$10.2M +$444K +43,586 +4%
Jacobs Levy Equity Management
13
Jacobs Levy Equity Management
New Jersey
$9.34M +$1.03M +101,483 +12%
Federated Hermes
14
Federated Hermes
Pennsylvania
$9.31M +$2.87M +281,549 +41%
Goldman Sachs
15
Goldman Sachs
New York
$8.93M +$5.93M +582,112 +165%
Citadel Advisors
16
Citadel Advisors
Florida
$8.71M +$1.48M +145,277 +19%
Point72 Asset Management
17
Point72 Asset Management
Connecticut
$8.21M +$2.17M +213,272 +33%
Dimensional Fund Advisors
18
Dimensional Fund Advisors
Texas
$7.4M -$324K -31,781 -4%
N
19
Nuveen
North Carolina
$7.25M +$925K +90,817 +14%
Two Sigma Investments
20
Two Sigma Investments
New York
$6.4M +$2.48M +243,533 +57%
Mariner
21
Mariner
Kansas
$5.52M -$132K -12,959 -2%
RC
22
Rangeley Capital
Connecticut
$5.01M -$365K -35,857 -6%
BC
23
Birchview Capital
Vermont
$4.21M -$1.1M -108,000 -20%
Renaissance Technologies
24
Renaissance Technologies
New York
$4.16M +$654K +64,215 +17%
Jane Street
25
Jane Street
New York
$4.09M -$1.95M -191,141 -31%