Company · Ownership research

Sionna Therapeutics, Inc. SION

CIK 0002036042

Form 4 transactions dated Nov 1, 2023 to Nov 8, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

Insider filings on file run through Sep 21, 2026.

Some filings are submitted jointly by several insiders. The SEC form does not apportion the reported figures between them, so results include every joint filer.

Insider purchases & sales

Purchased: $63.41M
Sold: $196.47M

Nov 1, 2023 – Sep 21, 2026
Available records · partial months are marked ·

Insiders in this window

202610 of 30 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
Sep 17, 2026	RA Capital Healthcare Fund LP · RA CAPITAL MANAGEMENT, L.P. · Kolchinsky Peter · Shah Rajeev M. · RA Capital Nexus Fund, L.P. · RA Capital Nexus Fund III, L.P. Director	Sale	$21.84M 3,448,811 shares sold	Unavailable Indirect holding	▾
Jul 7, 2026	Thompson Peter A. Director	Sale10b5-1 footnote	$3.85M 85,918 shares sold	3.36% sold Indirect holding	▾
Jul 7, 2026	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale10b5-1 footnote	$3.85M 85,918 shares sold	Unavailable Indirect holding	▾
Jul 6, 2026	Fitzpatrick Jennifer Chief Legal Officer	Sale10b5-1 footnote	$446.86K 10,250 shares sold	100.00% sold Direct holding	▾
Jun 30, 2026	Thompson Peter A. Director	Sale10b5-1 footnote	$5.27M 115,844 shares sold	4.34% sold Indirect holding	▾
Jun 30, 2026	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale10b5-1 footnote	$5.27M 115,844 shares sold	Unavailable Indirect holding	▾
May 27, 2026	Thompson Peter A. Director	Sale10b5-1 footnote	$4.49K 101 shares sold	<0.01% sold Indirect holding	▾
May 27, 2026	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale10b5-1 footnote	$4.49K 101 shares sold	Unavailable Indirect holding	▾
May 11, 2026	Thompson Peter A. Director	Sale10b5-1 footnote	$8.53M 184,639 shares sold	6.46% sold Indirect holding	▾
May 11, 2026	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale10b5-1 footnote	$8.53M 184,639 shares sold	Unavailable Indirect holding	▾

Showing 30 / 30 record groups in 2026. The complete set is available through the API.

Sionna Therapeutics, Inc. · SION

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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.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Share totals are on today's split-adjusted basis. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.