Latest Period
Q2 2026
CUSIP: 829401108
Latest Period
Q2 2026
Institutions Reporting
34
Shares (Excl. Options)
4,470,818
Price
$43.99
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Latest holder context comes from 34 institutions filings for Q2 2026.
Security key
829401108
Latest holder period
Q2 2026
13F holders
34
13D/G owners
8
CIK / CUSIP context first
Broader feeds
Open recent reporting periods for CUSIP 829401108:
13D/G owners
Large-stake holder rows connected to Schedule 13D/G evidence.
| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | 23% | -4.6% | $296,218,114 | -$10,988,206 | 10,071,712 | -3.6% | RA Capital Management, L.P. | 05 Nov 2025 |
| TPG GP A, LLC | 15% | $80,486,942 | 6,684,962 | TPG GP A, LLC | 10 Feb 2025 | |||
| VIKING GLOBAL INVESTORS LP | 7.1% | +5.7% | $133,462,710 | +$10,126,176 | 3,195,181 | +8.2% | VIKING GLOBAL INVESTORS LP | 31 Mar 2026 |
| ORBIMED ADVISORS LLC | 6.6% | -22% | $118,970,633 | -$29,554,504 | 2,967,722 | -20% | ORBIMED ADVISORS LLC | 15 Apr 2026 |
| Enavate Sciences GP, LLC | 5.6% | $29,835,481 | 2,478,030 | Enavate Sciences GP, LLC | 10 Feb 2025 | |||
| Atlas Venture Fund XI, L.P. | 5.4% | -16% | $74,744,824 | -$15,805,403 | 2,382,495 | -17% | Atlas Venture Fund XI, L.P. | 16 Oct 2025 |
| Qatar Investment Authority | 4.5% | -10% | $84,386,177 | -$7,916,125 | 2,020,258 | -8.6% | Qatar Investment Authority | 31 Mar 2026 |
| JPMORGAN CHASE & CO | 4.4% | -12% | $58,251,993 | -$7,075,145 | 1,980,626 | -11% | JPMORGAN CHASE & CO. | 30 Sep 2025 |
As of 30 Jun 2026, 34 institutional investors reported holding 4,470,818 shares of Sionna Therapeutics, Inc. - Common Stock, $0.001 par value per share (SION). This represents 9.9% of the company’s total 45,002,549 outstanding shares.
Quarter history
Holder count, reported shares/value, and median price by quarter.
| Period | 13F Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2026 Q2 | 4,470,818 | $196,671,311 | +$4,465,632 | $43.99 | 34 |
| 2026 Q1 | 45,407,309 | $1,815,366,651 | +$51,789,321 | $40.09 | 121 |
| 2025 Q4 | 43,950,880 | $1,808,143,956 | +$42,254,824 | $41.14 | 101 |
| 2025 Q3 | 42,840,564 | $1,259,943,482 | -$14,718,322 | $29.41 | 78 |
| 2025 Q2 | 43,448,393 | $753,831,077 | +$37,292,994 | $17.35 | 65 |
| 2025 Q1 | 41,491,947 | $434,056,422 | +$434,056,422 | $10.46 | 47 |