Group One Trading
PRTA icon

Group One Trading’s Prothena Corp PRTA Stock Holding History

Group One 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 		– Sell
-3,416
Closed -$33.7K – 8298
2026
Q1 		$33.2K Buy
+3,416
New +$31.3K ﹤0.01% 5583
2025
Q4 		– Sell
-6,949
Closed -$70.7K – 8947
2025
Q3 		$67.8K Sell
6,949
-25,309
-78% -$195K ﹤0.01% 5709
2025
Q2 		$196K Buy
+32,258
New +$242K ﹤0.01% 4364
2025
Q1 		– Sell
-4,824
Closed -$68.2K – 8222
2024
Q4 		$66.8K Sell
4,824
-2,610
-35% -$41.2K ﹤0.01% 4838
2024
Q3 		$124K Buy
7,434
+1,201
+19% +$25.8K ﹤0.01% 4000
2024
Q2 		$129K Buy
6,233
+3,937
+171% +$85.2K ﹤0.01% 3755
2024
Q1 		$56.9K Sell
2,296
-25,160
-92% -$748K ﹤0.01% 4608
2023
Q4 		$998K Buy
+27,456
New +$1.06M ﹤0.01% 2463
2022
Q4 		– Sell
-3,813
Closed -$223K – 7919
2022
Q3 		$231K Buy
+3,813
New +$121K ﹤0.01% 3994
2022
Q2 		– Sell
-1,029
Closed -$30.1K – 8371
2022
Q1 		$38K Sell
1,029
-3,159
-75% -$114K ﹤0.01% 6319
2021
Q4 		$207K Buy
4,188
+2,251
+116% +$125K ﹤0.01% 5056
2021
Q3 		$138K Buy
+1,937
New +$120K ﹤0.01% 5572
2021
Q2 		– Sell
-7,550
Closed -$236K – 8490
2021
Q1 		$190K Sell
7,550
-4,896
-39% -$92.1K ﹤0.01% 5082
2020
Q4 		$149K Buy
12,446
+2,211
+22% +$26.1K ﹤0.01% 4284
2020
Q3 		$102K Buy
10,235
+1,690
+20% +$20.3K ﹤0.01% 4182
2020
Q2 		$89K Sell
8,545
-10,317
-55% -$115K ﹤0.01% 4002
2020
Q1 		$202K Sell
18,862
-8,696
-32% -$105K ﹤0.01% 2742
2019
Q4 		$436K Buy
27,558
+21,374
+346% +$229K ﹤0.01% 2546
2019
Q3 		$48K Sell
6,184
-7,103
-53% -$63.1K ﹤0.01% 3991
2019
Q2 		$140K Buy
13,287
+7,560
+132% +$77.6K ﹤0.01% 3104
2019
Q1 		$69K Sell
5,727
-32,657
-85% -$408K ﹤0.01% 3407
2018
Q4 		$395K Buy
38,384
+1,853
+5% +$22K ﹤0.01% 2153
2018
Q3 		$478K Sell
36,531
-11,697
-24% -$169K ﹤0.01% 2331
2018
Q2 		$703K Buy
48,228
+31,069
+181% +$614K 0.01% 2021
2018
Q1 		$630K Buy
17,159
+13,872
+422% +$505K 0.01% 1871
2017
Q4 		$123K Buy
+3,287
New +$167K ﹤0.01% 3239
2017
Q1 		– Sell
-1,950
Closed -$102K – 4920
2016
Q4 		$96K Sell
1,950
-30,290
-94% -$1.67M ﹤0.01% 2868
2016
Q3 		$1.93M Buy
32,240
+23,248
+259% +$1.25M 0.02% 871
2016
Q2 		$314K Buy
8,992
+5,619
+167% +$245K ﹤0.01% 2082
2016
Q1 		$139K Sell
3,373
-24,350
-88% -$953K ﹤0.01% 2589
2015
Q4 		$1.89M Sell
27,723
-9,970
-26% -$601K 0.02% 887
2015
Q3 		$1.71M Buy
37,693
+3,534
+10% +$206K 0.02% 889
2015
Q2 		$1.8M Buy
34,159
+16,932
+98% +$668K 0.03% 817
2015
Q1 		$657K Buy
17,227
+8,558
+99% +$220K 0.01% 1398
2014
Q4 		$180K Sell
8,669
-10,758
-55% -$224K ﹤0.01% 2384
2014
Q3 		$431K Sell
19,427
-4,431
-19% -$93.9K 0.01% 1730
2014
Q2 		$538K Buy
23,858
+5,602
+31% +$140K 0.01% 1584
2014
Q1 		$699K Buy
+18,256
New +$589K 0.01% 1373
2013
Q4 		– Sell
-928
Closed -$23.3K – 5476
2013
Q3 		$19K Sell
928
-3,147
-77% -$55.7K ﹤0.01% 4209
2013
Q2 		$53K Buy
+4,075
New +$37.9K ﹤0.01% 3379

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

Group One Trading's PRTA Position: Q2 2026 in Review

Group One Trading sold out of Prothena Corp (PRTA) in Q2 2026, closing a stake of 3,416 shares — an estimated $33.7K sold.

Group One Trading first reported a position in PRTA in Q2 2013 and held it in 40 quarters. The position peaked at $1.93M in Q3 2016. 188 funds tracked by Wall St. Rank hold PRTA as of Q2 2026.

  • Group One Trading reported no remaining Prothena Corp position as of Q2 2026 after selling out during the quarter.
  • Group One Trading sold 3,416 Prothena Corp shares in Q2 2026, an estimated $33.7K.
  • Group One Trading first reported a position in Prothena Corp in Q2 2013 and held it in 40 quarters.
  • Group One Trading's Prothena Corp position peaked at $1.93M in Q3 2016.
  • 188 funds tracked by Wall St. Rank held Prothena Corp as of Q2 2026.

Based on Group One Trading's 13F filing for Q2 2026, filed 14 Aug 2026.