Jim Simons
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Jim Simons’s Prothena Corp PRTA Stock Holding History

Jim Simons’s Portfolio PRTA Stock Details PRTA Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$5.91M Buy
607,515
+172,000
+39% +$1.58M 0.01% 1279
2025
Q4 		$4.16M Buy
435,515
+64,215
+17% +$654K 0.01% 1406
2025
Q3 		$3.62M Buy
371,300
+281,100
+312% +$2.16M ﹤0.01% 1673
2025
Q2 		$548K Sell
90,200
-149,700
-62% -$1.12M ﹤0.01% 2788
2025
Q1 		$2.97M Buy
239,900
+38,000
+19% +$537K ﹤0.01% 1752
2024
Q4 		$2.8M Buy
201,900
+19,100
+10% +$301K ﹤0.01% 1832
2024
Q3 		$3.06M Sell
182,800
-146,700
-45% -$3.15M ﹤0.01% 1749
2024
Q2 		$6.8M Sell
329,500
-60,200
-15% -$1.3M 0.01% 1125
2024
Q1 		$9.65M Buy
389,700
+53,900
+16% +$1.6M 0.02% 1006
2023
Q4 		$12.2M Buy
335,800
+75,200
+29% +$2.89M 0.02% 849
2023
Q3 		$12.6M Sell
260,600
-63,200
-20% -$3.75M 0.02% 790
2023
Q2 		$22.1M Sell
323,800
-83,500
-21% -$5.39M 0.03% 632
2023
Q1 		$19.7M Sell
407,300
-67,600
-14% -$3.57M 0.03% 722
2022
Q4 		$28.6M Sell
474,900
-162,000
-25% -$9.49M 0.04% 552
2022
Q3 		$38.6M Sell
636,900
-49,100
-7% -$1.55M 0.05% 405
2022
Q2 		$18.6M Buy
686,000
+291,800
+74% +$8.54M 0.02% 772
2022
Q1 		$14.4M Buy
394,200
+127,400
+48% +$4.59M 0.02% 923
2021
Q4 		$13.2M Buy
266,800
+9,600
+4% +$532K 0.02% 936
2021
Q3 		$18.3M Buy
257,200
+18,900
+8% +$1.17M 0.02% 716
2021
Q2 		$12.3M Sell
238,300
-50,700
-18% -$1.58M 0.02% 1036
2021
Q1 		$7.26M Sell
289,000
-25,000
-8% -$470K 0.01% 1407
2020
Q4 		$3.77M Buy
314,000
+48,800
+18% +$577K ﹤0.01% 1762
2020
Q3 		$2.65M Sell
265,200
-122,762
-32% -$1.48M ﹤0.01% 1960
2020
Q2 		$4.06M Buy
387,962
+303,062
+357% +$3.37M ﹤0.01% 1772
2020
Q1 		$908K Buy
84,900
+15,800
+23% +$191K ﹤0.01% 2476
2019
Q4 		$1.09M Buy
69,100
+24,100
+54% +$258K ﹤0.01% 2586
2019
Q3 		$353K Buy
+45,000
New +$400K ﹤0.01% 2987
2019
Q2 		– Sell
-12,800
Closed -$155K – 3718
2019
Q1 		$155K Buy
+12,800
New +$160K ﹤0.01% 3243
2018
Q4 		– Sell
-57,400
Closed -$751K – 3558
2018
Q3 		$751K Buy
+57,400
New +$829K ﹤0.01% 2726
2018
Q1 		– Sell
-42,700
Closed -$1.6M – 3528
2017
Q4 		$1.6M Buy
+42,700
New +$2.17M ﹤0.01% 2464
2016
Q1 		– Sell
-90,600
Closed -$6.17M – 3499
2015
Q4 		$6.17M Buy
90,600
+54,200
+149% +$3.27M 0.01% 1329
2015
Q3 		$1.65M Buy
+36,400
New +$2.12M ﹤0.01% 2110
2014
Q4 		– Sell
-17,300
Closed -$383K – 3084
2014
Q3 		$383K Sell
17,300
-34,600
-67% -$734K ﹤0.01% 2400
2014
Q2 		$1.17M Sell
51,900
-27,212
-34% -$680K ﹤0.01% 1983
2014
Q1 		$3.03M Buy
79,112
+14,512
+22% +$468K 0.01% 1548
2013
Q4 		$1.71M Buy
+64,600
New +$1.62M ﹤0.01% 1832

Other funds holding PRTA

Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
RCMNY
Rubric Capital Management (New York) New York $9.44B AUM 68.42% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
D.E. Shaw & Co
D.E. Shaw & Co New York $166B AUM 43.98% 1-Year Est. Return
ACM
ADAR1 Capital Management Austin, Texas $1.7B AUM 340.85% 1-Year Est. Return
Acadian Asset Management
Acadian Asset Management Boston, Massachusetts $70.5B AUM 36% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
Morgan Stanley
Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return
PAI
Palo Alto Investors Palo Alto, California $654M AUM 77.8% 1-Year Est. Return

Jim Simons's PRTA Position: Q1 2026 in Review

Jim Simons increased its Prothena Corp (PRTA) stake by 39% in Q1 2026, buying an estimated $1.58M and bringing the position to 607,515 shares worth $5.91M. The position accounts for 0.01% of the portfolio, ranked #1279.

Jim Simons first reported a position in PRTA in Q4 2013 and has held it in 36 quarters since. The position peaked at $38.6M in Q3 2022. 185 funds tracked by Wall St. Rank hold PRTA as of Q1 2026.

  • Jim Simons held 607,515 shares of Prothena Corp worth $5.91M as of Q1 2026.
  • Jim Simons bought 172,000 Prothena Corp shares in Q1 2026, an estimated $1.58M.
  • Prothena Corp made up 0.01% of Jim Simons's portfolio in Q1 2026, its #1279 holding.
  • Jim Simons first reported a position in Prothena Corp in Q4 2013 and has held it in 36 quarters since.
  • Jim Simons's Prothena Corp position peaked at $38.6M in Q3 2022.
  • 185 funds tracked by Wall St. Rank held Prothena Corp as of Q1 2026.

Based on Renaissance Technologies's 13F filing for Q1 2026, filed 14 May 2026.