Marshall Wace
SION

Marshall Wace’s Sionna Therapeutics SION Stock Holding History

Marshall Wace’s Portfolio SION Stock Details SION Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$554K Buy
+12,599
New +$504K ﹤0.01% 2472
2025
Q4 		– Sell
-30,103
Closed -$885K – 3617
2025
Q3 		$885K Buy
+30,103
New +$655K ﹤0.01% 1993
2025
Q2 		– Sell
-12,188
Closed -$127K – 3298
2025
Q1 		$127K Buy
+12,188
New +$199K ﹤0.01% 2471

Other funds holding SION

RCM
RA Capital Management Boston, Massachusetts $11.5B AUM 168.77% 1-Year Est. Return
TGA
TPG GP A Fort Worth, Texas $5B AUM 58.56% 1-Year Est. Return
Viking Global Investors
Viking Global Investors Stamford, Connecticut $35.1B AUM 21.36% 1-Year Est. Return
AVLSA
Atlas Venture Life Science Advisors Cambridge, Massachusetts $881M AUM 160.77% 1-Year Est. Return
O
OrbiMed New York $5.4B AUM 163.13% 1-Year Est. Return
ES
Enavate Sciences Menlo Park, California $345M AUM 134.64% 1-Year Est. Return
Adage Capital Partners
Adage Capital Partners Boston, Massachusetts $71.3B AUM 56.8% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return
Jennison Associates
Jennison Associates New York $167B AUM 44.17% 1-Year Est. Return

Marshall Wace's SION Position: Q2 2026 in Review

Marshall Wace opened a new position in Sionna Therapeutics (SION) in Q2 2026: 12,599 shares worth $554K. The stake represents ﹤0.01% of the portfolio and ranks #2472 among its holdings. This is a return to the name: Marshall Wace previously reported a position in SION as recently as Q3 2025.

Marshall Wace first reported a position in SION in Q1 2025 and has held it in 3 quarters since. The position peaked at $885K in Q3 2025. 147 funds tracked by Wall St. Rank hold SION as of Q2 2026.

  • Marshall Wace held 12,599 shares of Sionna Therapeutics worth $554K as of Q2 2026.
  • Sionna Therapeutics was a new Marshall Wace position in Q2 2026.
  • Sionna Therapeutics made up ﹤0.01% of Marshall Wace's portfolio in Q2 2026, its #2472 holding.
  • Marshall Wace first reported a position in Sionna Therapeutics in Q1 2025 and has held it in 3 quarters since.
  • Marshall Wace's Sionna Therapeutics position peaked at $885K in Q3 2025.
  • 147 funds tracked by Wall St. Rank held Sionna Therapeutics as of Q2 2026.

Based on Marshall Wace's 13F filing for Q2 2026, filed 13 Aug 2026.