Arrowstreet Capital
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Arrowstreet Capital’s Ionis Pharmaceuticals IONS Stock Holding History

Arrowstreet Capital’s Portfolio IONS Stock Details IONS Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$50.1M Sell
632,028
-105,831
-14% -$7.96M 0.02% 562
2026
Q1 		$55.4M Sell
737,859
-325,468
-31% -$25.7M 0.03% 465
2025
Q4 		$84.1M Buy
1,063,327
+433,191
+69% +$32.6M 0.05% 331
2025
Q3 		$41.2M Buy
+630,136
New +$30.8M 0.03% 519
2022
Q3 		– Sell
-41,104
Closed -$1.52M – 1366
2022
Q2 		$1.52M Buy
+41,104
New +$1.55M ﹤0.01% 843
2021
Q4 		– Sell
-41,100
Closed -$1.38M – 1569
2021
Q3 		$1.38M Sell
41,100
-51,800
-56% -$1.95M ﹤0.01% 1214
2021
Q2 		$3.71M Buy
+92,900
New +$3.64M ﹤0.01% 1158
2020
Q4 		– Sell
-26,000
Closed -$1.23M – 2408
2020
Q3 		$1.23M Buy
+26,000
New +$1.44M ﹤0.01% 1755
2020
Q1 		– Sell
-14,157
Closed -$855K – 1983
2019
Q4 		$855K Sell
14,157
-1,843
-12% -$110K ﹤0.01% 1377
2019
Q3 		$959K Buy
+16,000
New +$1.04M ﹤0.01% 1177
2019
Q2 		– Sell
-184,174
Closed -$14.9M – 1525
2019
Q1 		$14.9M Buy
+184,174
New +$11.9M 0.04% 438
2016
Q4 		– Sell
-704,855
Closed -$25.8M – 2072
2016
Q3 		$25.8M Buy
+704,855
New +$22.1M 0.08% 235
2015
Q3 		– Sell
-387,915
Closed -$22.3M – 1420
2015
Q2 		$22.3M Buy
+387,915
New +$24.7M 0.13% 170
2013
Q4 		– Sell
-155,564
Closed -$5.84M – 1218
2013
Q3 		$5.84M Buy
+155,564
New +$4.65M 0.04% 353

Other funds holding IONS

Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
Capital World Investors
Capital World Investors Los Angeles, California $846B AUM 46.74% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
Wellington Management Group
Wellington Management Group Boston, Massachusetts $580B AUM 38.23% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
Two Sigma Investments
Two Sigma Investments New York $138B AUM 41.87% 1-Year Est. Return
Royal Bank of Canada
Royal Bank of Canada Toronto, Ontario, Canada $672B AUM 33.48% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
T. Rowe Price Investment Management
T. Rowe Price Investment Management Baltimore, Maryland $153B AUM 38.14% 1-Year Est. Return

Arrowstreet Capital's IONS Position: Q2 2026 in Review

Arrowstreet Capital reduced its Ionis Pharmaceuticals (IONS) stake by 14% in Q2 2026, selling an estimated $7.96M and leaving 632,028 shares worth $50.1M. The position accounts for 0.02% of the portfolio, ranked #562.

Arrowstreet Capital first reported a position in IONS in Q3 2013 and has held it in 14 quarters since. The position peaked at $84.1M in Q4 2025. 513 funds tracked by Wall St. Rank hold IONS as of Q2 2026.

  • Arrowstreet Capital held 632,028 shares of Ionis Pharmaceuticals worth $50.1M as of Q2 2026.
  • Arrowstreet Capital sold 105,831 Ionis Pharmaceuticals shares in Q2 2026, an estimated $7.96M.
  • Ionis Pharmaceuticals made up 0.02% of Arrowstreet Capital's portfolio in Q2 2026, its #562 holding.
  • Arrowstreet Capital first reported a position in Ionis Pharmaceuticals in Q3 2013 and has held it in 14 quarters since.
  • Arrowstreet Capital's Ionis Pharmaceuticals position peaked at $84.1M in Q4 2025.
  • 513 funds tracked by Wall St. Rank held Ionis Pharmaceuticals as of Q2 2026.

Based on Arrowstreet Capital's 13F filing for Q2 2026, filed 13 Aug 2026.