Company · Ownership research

Sionna Therapeutics, Inc. SION

CIK 0002036042 · CUSIP 829401108

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

This page lists the top 20 of 101 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	RA CAPITAL MANAGEMENT, L.P. CIK 1346824 · View history	$407.49M 9,905,045 shares	4.17%	-540.28K(-5.20%)Reduced	SEC filing ↗ Feb 17, 2026	▾
02	TPG GP A, LLC CIK 1903793 · View history	$277.49M 6,744,962 shares	10.33%	0(0.00%)Unchanged	SEC filing ↗ Feb 13, 2026	▾
03	ORBIMED ADVISORS LLC CIK 1055951 · View history	$146.53M 3,561,655 shares	3.01%	-143.30K(-3.90%)Reduced	SEC filing ↗ Feb 17, 2026	▾
04	VIKING GLOBAL INVESTORS LP CIK 1103804 · View history	$131.45M 3,195,181 shares	0.35%	0(0.00%)Unchanged	SEC filing ↗ Feb 17, 2026	▾
05	Atlas Venture Life Science Advisors, LLC CIK 1917529 · View history	$123.24M 2,995,602 shares	14.24%	-619.92K(-17.10%)Reduced	SEC filing ↗ Feb 13, 2026	▾
06	ENAVATE SCIENCES GP, LLC CIK 1953107 · View history	$101.95M 2,478,030 shares	20.12%	0(0.00%)Unchanged	SEC filing ↗ Feb 17, 2026	▾
07	BlackRock, Inc. CIK 2012383 · View history	$53.14M 1,291,599 shares	0.00%	+446.99K(+52.90%)Added	SEC filing ↗ Feb 12, 2026	▾
08	JPMORGAN CHASE & CO CIK 19617 · View history	$50.68M 1,231,819 shares	0.00%	-746.81K(-37.70%)Reduced	SEC filing ↗ Feb 11, 2026	▾
09	VANGUARD GROUP INC CIK 102909 · View history	$48.75M 1,184,951 shares	0.00%	+41.80K(+3.70%)Added	SEC filing ↗ Jan 29, 2026	▾
10	PERCEPTIVE ADVISORS LLC CIK 1224962 · View history	$48.51M 1,179,098 shares	0.89%	0(0.00%)Unchanged	SEC filing ↗ Feb 17, 2026	▾
11	JENNISON ASSOCIATES LLC CIK 53417 · View history	$45.88M 1,115,278 shares	0.03%	+117.90K(+11.80%)Added	SEC filing ↗ Jan 30, 2026	▾
12	CITADEL ADVISORS LLC CIK 1423053 · View history	$44.73M 1,087,325 shares	0.03%	+1.05M(+2,926.80%)Added	SEC filing ↗ Feb 17, 2026	▾
13	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) CIK 1009258 · View history	$39.93M 970,590 shares	0.51%	0(0.00%)Unchanged	SEC filing ↗ Feb 17, 2026	▾
14	Aberdeen Group plc CIK 1716774 · View history	$34.56M 839,960 shares	0.05%	-110.59K(-11.60%)Reduced	SEC filing ↗ Jan 16, 2026	▾
15	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$34.20M 831,373 shares	0.00%	+193.61K(+30.40%)Added	SEC filing ↗ Feb 17, 2026	▾
16	STATE STREET CORP CIK 93751 · View history	$28.53M 693,395 shares	0.00%	+453.20K(+188.70%)Added	SEC filing ↗ Feb 13, 2026	▾
17	EVENTIDE ASSET MANAGEMENT, LLC CIK 1442891 · View history	$26.29M 639,045 shares	0.41%	+639.04KNew	SEC filing ↗ Feb 13, 2026	▾
18	BAKER BROS. ADVISORS LP CIK 1263508 · View history	$16.46M 400,000 shares	0.10%	0(0.00%)Unchanged	SEC filing ↗ Feb 17, 2026	▾
19	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$15.64M 380,042 shares	0.00%	+63.48K(+20.10%)Added	SEC filing ↗ Feb 9, 2026	▾
20	Siren, L.L.C. CIK 2005245 · View history	$12.34M 300,000 shares	0.37%	-25.00K(-7.70%)Reduced	SEC filing ↗ Feb 13, 2026	▾

Showing 20 / 101 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

101

Cancelled or null records excluded

Disclosed shares

43,950,895

Not deduplicated across managers

Disclosed value

$1.81B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

Sionna Therapeutics, Inc. · Q4 2025

Explore all 101 reporting institutions.

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.