Thompson Peter A. sold ~$33M in Sionna Therapeutics, Inc. Common Stock stock
Sionna Therapeutics, Inc. Common Stock (SION) · Data via SEC EDGAR Form 4
Price Performance · 10 days before → 90 days after trade
▲ = insider buy date
Trade Details · Public SEC Filing
Insider
Thompson Peter A.
Role
—
Transaction
Open-Market Sale
Approx. Value
~$33M
Trade Date
Nov 26, 2025
Company
Sionna Therapeutics, Inc. Common Stock
Ticker
SIONSource
SEC EDGAR Form 4
Why This Trade Stands Out
Strong conviction signal
Scored above average across multiple factors. Roughly 15% of insider trades qualify as Strong.
~$33M sale
Trades over $1M are rare. When insiders put this much of their own money on the line, they tend to have high conviction in their company's direction.
3 insiders traded in the same window
When multiple insiders independently buy within 30 days, it's called a cluster. Studies show clustered insider purchases outperform solo trades significantly, because several people with inside knowledge are reaching the same conclusion.
How good is Thompson Peter A. at picking stocks?
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Thompson Peter A. wasn't the only one selling.
3 insiders at Sionna Therapeutics, Inc. Common Stock traded within the same 30-day window.
See who else bought · FreeOn November 26, 2025, Thompson Peter A. — a corporate insider at Sionna Therapeutics, Inc. Common Stock — filed a Form 4 with the SEC disclosing an open-market sale of approximately ~$33M in Sionna Therapeutics, Inc. Common Stock (SION) stock.
This transaction was part of a cluster — 3 insiders at Sionna Therapeutics, Inc. Common Stock made open-market sales within the same 30-day window. Cluster activity from multiple independent insiders is one of the most studied patterns in insider trading research.
Under Section 16(a) of the Securities Exchange Act of 1934, corporate insiders must report all open-market stock transactions to the SEC within two business days. These filings — known as Form 4s — are publicly available on the SEC's EDGAR database. VeritySignals filters and scores the full Form 4 stream to surface high-conviction signals like this one.
VeritySignals Conviction Analysis
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All data sourced from publicly available SEC Form 4 filings via EDGAR · Not financial advice · Past performance does not guarantee future results.
At a Glance
How to Read Insider Trades
What is this?
When company executives buy or sell their own stock, they must report it to the SEC within 2 days. These public filings reveal what the people who know the company best are doing with their own money.
Why does it matter?
Insiders can sell for many reasons (taxes, diversification, expenses), but they generally only buy for one: they think the stock is going up. That's why insider purchases are more predictive than sales.
What makes a trade "strong"?
We score trades on 15+ factors: the insider's role (CEO > director), trade size relative to their salary, whether other insiders also bought (clusters), and historical accuracy of the insider.
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