Simplex Trading
PRTA icon

Simplex Trading’s Prothena Corp PRTA Stock Holding History

Simplex Trading’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
Q2 		$595K Buy
60,800
+26,500
+77% +$262K ﹤0.01% 3378
2026
Q1 		$333K Sell
34,300
-126,000
-79% -$1.15M ﹤0.01% 3704
2025
Q4 		$1.53M Sell
160,300
-104,900
-40% -$1.07M ﹤0.01% 2202
2025
Q3 		$2.59M Buy
265,200
+103,700
+64% +$797K ﹤0.01% 2068
2025
Q2 		$980K Buy
161,500
+161,000
+32,200% +$1.21M ﹤0.01% 2802
2025
Q1 		$6K Sell
500
-22,400
-98% -$317K ﹤0.01% 7477
2024
Q4 		$317K Buy
22,900
+11,800
+106% +$186K ﹤0.01% 4009
2024
Q3 		$185K Buy
11,100
+2,000
+22% +$43K ﹤0.01% 4595
2024
Q2 		$187K Sell
9,100
-12,400
-58% -$268K ﹤0.01% 4716
2024
Q1 		$532K Sell
21,500
-61,800
-74% -$1.84M ﹤0.01% 3802
2023
Q4 		$3.03M Buy
83,300
+83,100
+41,550% +$3.2M ﹤0.01% 1998
2023
Q3 		$9K Sell
200
-13,000
-98% -$772K ﹤0.01% 7266
2023
Q2 		$901K Buy
13,200
+8,000
+154% +$516K ﹤0.01% 2696
2023
Q1 		$252K Sell
5,200
-20,500
-80% -$1.08M ﹤0.01% 4054
2022
Q4 		$1.55M Sell
25,700
-52,500
-67% -$3.07M ﹤0.01% 2068
2022
Q3 		$4.74M Buy
78,200
+76,400
+4,244% +$2.42M 0.01% 1239
2022
Q2 		$48K Buy
+1,800
New +$52.7K ﹤0.01% 6555
2022
Q1 		– Sell
-900
Closed -$44K – 11192
2021
Q4 		$44K Sell
900
-5,600
-86% -$311K ﹤0.01% 7428
2021
Q3 		$343K Hold
6,500
– – ﹤0.01% 4691
2021
Q2 		$334K Buy
6,500
+6,478
+29,445% +$202K ﹤0.01% 4786
2021
Q1 		$55K Buy
22
+10
+83% +$188 ﹤0.01% 6495
2020
Q4 		$14K Sell
12
-287
-96% -$3.39K ﹤0.01% 7207
2020
Q3 		$298K Buy
299
+19
+7% +$229 ﹤0.01% 3608
2020
Q2 		$292K Buy
280
+262
+1,456% +$2.91K ﹤0.01% 3559
2020
Q1 		$19K Sell
18
-2
-10% -$24 ﹤0.01% 6002
2019
Q4 		$31K Buy
20
+8
+67% +$86 ﹤0.01% 5634
2019
Q3 		$9K Hold
12
– – ﹤0.01% 6305
2019
Q2 		$12K Buy
12
+2
+20% +$21 ﹤0.01% 6009
2019
Q1 		$12K Sell
10
-423
-98% -$5.28K ﹤0.01% 6056
2018
Q4 		$445K Sell
433
-324
-43% -$3.85K ﹤0.01% 2339
2018
Q3 		$990K Buy
757
+204
+37% +$2.95K ﹤0.01% 1898
2018
Q2 		$806K Buy
553
+400
+261% +$7.9K ﹤0.01% 1982
2018
Q1 		$77K Buy
153
+16
+12% +$582 ﹤0.01% 2015
2017
Q4 		$188K Sell
137
-262
-66% -$13.3K 0.01% 1317
2017
Q3 		$34K Buy
399
+312
+359% +$19.1K ﹤0.01% 2656
2017
Q2 		$24K Sell
87
-76
-47% -$4.05K ﹤0.01% 3131
2017
Q1 		$37K Buy
163
+57
+54% +$3K ﹤0.01% 2646
2016
Q4 		$70K Sell
106
-80
-43% -$4.41K ﹤0.01% 1827
2016
Q3 		$36K Buy
186
+128
+221% +$6.87K ﹤0.01% 2400
2016
Q2 		$69K Buy
58
+46
+383% +$2K ﹤0.01% 1764
2016
Q1 		$29K Sell
12
-332
-97% -$13K ﹤0.01% 2458
2015
Q4 		$228K Buy
344
+220
+177% +$13.3K 0.02% 804
2015
Q3 		$179K Buy
124
+103
+490% +$6K 0.01% 985
2015
Q2 		$1K Sell
21
-202
-91% -$7.97K ﹤0.01% 4765
2015
Q1 		$56K Buy
+223
New +$5.72K 0.01% 1478

Other funds holding PRTA

Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
RCMNY
Rubric Capital Management (New York) New York $10.9B AUM 70.31% 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
Acadian Asset Management
Acadian Asset Management Boston, Massachusetts $84.2B AUM 55.88% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
D.E. Shaw & Co
D.E. Shaw & Co New York $210B AUM 57.28% 1-Year Est. Return
ACM
ADAR1 Capital Management Austin, Texas $2.19B AUM 374.99% 1-Year Est. Return
Two Sigma Investments
Two Sigma Investments New York $138B AUM 41.87% 1-Year Est. Return
PAI
Palo Alto Investors Palo Alto, California $724M AUM 96.91% 1-Year Est. Return

Simplex Trading's PRTA Position: Q2 2026 in Review

Simplex Trading sold out of Prothena Corp (PRTA) in Q2 2026, closing a stake of 1,303 shares — an estimated $12.9K sold.

Simplex Trading first reported a position in PRTA in Q4 2014 and held it in 31 quarters. The position peaked at $1.43M in Q3 2022. 188 funds tracked by Wall St. Rank hold PRTA as of Q2 2026.

  • Simplex Trading reported no remaining Prothena Corp position as of Q2 2026 after selling out during the quarter.
  • Simplex Trading sold 1,303 Prothena Corp shares in Q2 2026, an estimated $12.9K.
  • Simplex Trading first reported a position in Prothena Corp in Q4 2014 and held it in 31 quarters.
  • Simplex Trading's Prothena Corp position peaked at $1.43M in Q3 2022.
  • 188 funds tracked by Wall St. Rank held Prothena Corp as of Q2 2026.

Based on Simplex Trading's 13F filing for Q2 2026, filed 12 Aug 2026.