| 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 | |||
| ORBIMED ADVISORS LLC | 8.4% | $44,607,706 | 3,704,959 | ORBIMED ADVISORS LLC | 10 Feb 2025 | |||
| VIKING GLOBAL INVESTORS LP | 6.7% | $35,551,158 | 2,952,754 | VIKING GLOBAL INVESTORS LP | 10 Feb 2025 | |||
| 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 | 5% | $28,351,413 | 2,209,775 | Qatar Investment Authority | 11 Jun 2025 | |||
| JPMORGAN CHASE & CO | 4.4% | -12% | $58,251,993 | -$7,075,145 | 1,980,626 | -11% | JPMORGAN CHASE & CO. | 30 Sep 2025 |
As of 31 Dec 2025, 100 institutional investors reported holding 43,948,480 shares of Sionna Therapeutics, Inc. - Common Stock, $0.001 par value per share (SION). This represents 99% of the company’s total 44,565,097 outstanding shares.
The largest institutional shareholders of Sionna Therapeutics, Inc. - Common Stock, $0.001 par value per share (SION) together control 94% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | 22% | 9,905,045 | -5.2% | 4.2% | $407,493,551 |
| TPG GP A, LLC | 15% | 6,744,962 | 0% | 10% | $277,487,737 |
| ORBIMED ADVISORS LLC | 8% | 3,561,655 | -3.9% | 3.1% | $146,526,487 |
| VIKING GLOBAL INVESTORS LP | 7.2% | 3,195,181 | 0% | 0.35% | $131,449,746 |
| Atlas Venture Life Science Advisors, LLC | 6.7% | 2,995,602 | -17% | 14% | $123,239,066 |
| ENAVATE SCIENCES GP, LLC | 5.6% | 2,478,030 | 0% | 20% | $101,946,154 |
| BlackRock, Inc. | 2.9% | 1,291,599 | +53% | 0% | $53,136,382 |
| JPMORGAN CHASE & CO | 2.8% | 1,231,819 | -38% | 0% | $50,677,035 |
| VANGUARD GROUP INC | 2.7% | 1,184,951 | +3.7% | 0% | $48,748,883 |
| PERCEPTIVE ADVISORS LLC | 2.6% | 1,179,098 | 0% | 0.89% | $48,508,092 |
| JENNISON ASSOCIATES LLC | 2.5% | 1,115,278 | +12% | 0.03% | $45,882,536 |
| CITADEL ADVISORS LLC | 2.4% | 1,087,325 | +2927% | 0.03% | $44,732,551 |
| DEERFIELD MANAGEMENT COMPANY, L.P. | 2.2% | 970,590 | 0% | 0.51% | $39,930,073 |
| Aberdeen Group plc | 1.9% | 839,960 | -12% | 0.05% | $34,555,954 |
| PRICE T ROWE ASSOCIATES INC /MD/ | 1.9% | 831,373 | +30% | 0% | $34,203,000 |
| STATE STREET CORP | 1.6% | 693,395 | +189% | 0% | $28,526,270 |
| EVENTIDE ASSET MANAGEMENT, LLC | 1.4% | 639,045 | 0.41% | $26,290,311 | |
| BAKER BROS. ADVISORS LP | 0.9% | 400,000 | 0% | 0.1% | $16,456,000 |
| GEODE CAPITAL MANAGEMENT, LLC | 0.85% | 380,042 | +20% | 0% | $15,638,406 |
| Siren, L.L.C. | 0.67% | 300,000 | -7.7% | 0.37% | $12,342,000 |
| Soleus Capital Management, L.P. | 0.6% | 268,500 | -35% | 0.47% | $11,046,090 |
| Kalehua Capital Management LLC | 0.44% | 197,072 | 0% | 8.2% | $8,107,542 |
| SUPERSTRING CAPITAL MANAGEMENT LP | 0.41% | 180,593 | 4% | $7,429,596 | |
| FRANKLIN RESOURCES INC | 0.39% | 175,483 | -28% | 0% | $7,219,371 |
| Alyeska Investment Group, L.P. | 0.31% | 136,222 | -27% | 0.02% | $5,604,173 |
| Period | Reported Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2025 Q4 | 43,948,480 | $1,808,044,956 | +$42,254,824 | $41.14 | 100 |
| 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 |