Giraudo Bryan sold ~$12M in Protagonist Therapeutics Inc stock
Protagonist Therapeutics Inc (PTGX) · Data via SEC EDGAR Form 4
Price Performance · 10 days before → 90 days after trade
▲ = insider buy date
Trade Details · Public SEC Filing
Insider
Giraudo Bryan
Role
—
Transaction
Open-Market Sale
Approx. Value
~$12M
Trade Date
May 8, 2026
Company
Protagonist Therapeutics Inc
Ticker
PTGXSource
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.
~$12M 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.
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On May 8, 2026, Giraudo Bryan — a corporate insider at Protagonist Therapeutics Inc — filed a Form 4 with the SEC disclosing an open-market sale of approximately ~$12M in Protagonist Therapeutics Inc (PTGX) stock.
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
More PTGX Insider Activity
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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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