Company · Ownership research

Sionna Therapeutics, Inc. SION

CIK 0002036042

Form 4 transactions dated Nov 1, 2023 to Nov 10, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

This page lists 30 of 71 rows; the complete set is available through the API.

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

202510 of 30 preview events · 71 available in 2025

Date	Insider	Activity	Trade value (USD)	% of prior holding
Dec 24, 2025	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale	$1.49M 33,356 shares sold	Unavailable Indirect holding	▾
Dec 24, 2025	Thompson Peter A. Director	Sale	$1.49M 33,356 shares sold	0.93% sold Indirect holding	▾
Dec 19, 2025	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale	$38.93K 875 shares sold	Unavailable Indirect holding	▾
Dec 19, 2025	Thompson Peter A. Director	Sale	$38.93K 875 shares sold	0.02% sold Indirect holding	▾
Dec 18, 2025	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale	$4.45K 100 shares sold	Unavailable Indirect holding	▾
Dec 18, 2025	Thompson Peter A. Director	Sale	$4.45K 100 shares sold	<0.01% sold Indirect holding	▾
Dec 17, 2025	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale	$40.05K 900 shares sold	Unavailable Indirect holding	▾
Dec 17, 2025	Thompson Peter A. Director	Sale	$40.05K 900 shares sold	0.03% sold Indirect holding	▾
Dec 5, 2025	Fitzpatrick Jennifer Chief Legal Officer	Sale10b5-1 footnote	$415.33K 10,250 shares sold	100.00% sold Direct holding	▾
Nov 26, 2025	ORBIMED ADVISORS LLC · OrbiMed Capital GP VIII LLC Director	Sale	$71.18K 1,600 shares sold	Unavailable Indirect holding	▾

Showing 30 / 71 record groups in 2025. The complete set is available through the API.

Sionna Therapeutics, Inc. · SION

Follow the people behind the trades.

Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and reach other datasets through the Akkru API.

Download CSV
Earlier filings
Advanced screening & filtering
API & AI access

Already have an account?

＋ New accounts get free API credits to explore data beyond ownership filings.

For AI agents & developers

The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 30 of 71 purchase / sale groups and 30 of 71 other groups; the totals and the monthly series cover the whole window.

Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP / CLI.

MCP  https://api.akkrudata.ai/mcp

akkru_insider_transactions
{"action":"list","ticker":"SION","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.

MCP endpoint: https://api.akkrudata.ai/mcp
API / MCP / CLI documentation: /documents
llms.txt: /llms.txt

Sources, coverage & how to read this data

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.