Citigroup
SION

Citigroup’s Sionna Therapeutics SION Stock Holding History

Citigroup’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 		$4.85M Buy
110,163
+92,105
+510% +$3.68M ﹤0.01% 2166
2026
Q1 		$724K Buy
18,058
+12,873
+248% +$491K ﹤0.01% 3318
2025
Q4 		$213K Buy
5,185
+4,498
+655% +$171K ﹤0.01% 3979
2025
Q3 		$20.2K Sell
687
-3,693
-84% -$80.3K ﹤0.01% 4810
2025
Q2 		$76K Buy
+4,380
New +$57.4K ﹤0.01% 4556

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

Citigroup's SION Position: Q2 2026 in Review

Citigroup increased its Sionna Therapeutics (SION) stake by 510% in Q2 2026, buying an estimated $3.68M and bringing the position to 110,163 shares worth $4.85M. The position accounts for ﹤0.01% of the portfolio, ranked #2166.

Citigroup first reported a position in SION in Q2 2025 and has held it in 5 quarters since. 146 funds tracked by Wall St. Rank hold SION as of Q2 2026.

  • Citigroup held 110,163 shares of Sionna Therapeutics worth $4.85M as of Q2 2026.
  • Citigroup bought 92,105 Sionna Therapeutics shares in Q2 2026, an estimated $3.68M.
  • Sionna Therapeutics made up ﹤0.01% of Citigroup's portfolio in Q2 2026, its #2166 holding.
  • Citigroup first reported a position in Sionna Therapeutics in Q2 2025 and has held it in 5 quarters since.
  • 146 funds tracked by Wall St. Rank held Sionna Therapeutics as of Q2 2026.

Based on Citigroup's 13F filing for Q2 2026, filed 3 Aug 2026.