XT
SION

XTX Topco’s Sionna Therapeutics SION Stock Holding History

XTX Topco’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 		$1.68M Buy
38,096
+14,545
+62% +$582K 0.02% 1293
2026
Q1 		$944K Buy
23,551
+18,625
+378% +$711K 0.02% 1462
2025
Q4 		$203K Buy
+4,926
New +$187K 0.01% 2395

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

XTX Topco's SION Position: Q2 2026 in Review

XTX Topco increased its Sionna Therapeutics (SION) stake by 62% in Q2 2026, buying an estimated $582K and bringing the position to 38,096 shares worth $1.68M. The position accounts for 0.02% of the portfolio, ranked #1293.

XTX Topco first reported a position in SION in Q4 2025 and has held it in 3 quarters since. 146 funds tracked by Wall St. Rank hold SION as of Q2 2026.

  • XTX Topco held 38,096 shares of Sionna Therapeutics worth $1.68M as of Q2 2026.
  • XTX Topco bought 14,545 Sionna Therapeutics shares in Q2 2026, an estimated $582K.
  • Sionna Therapeutics made up 0.02% of XTX Topco's portfolio in Q2 2026, its #1293 holding.
  • XTX Topco first reported a position in Sionna Therapeutics in Q4 2025 and has held it in 3 quarters since.
  • 146 funds tracked by Wall St. Rank held Sionna Therapeutics as of Q2 2026.

Based on XTX Topco's 13F filing for Q2 2026, filed 14 Aug 2026.