Form 4: Protagonist Director Sells Shares Under 10b5-1 Plan

Protagonist Therapeutics Director William D. Waddill exercised options and sold 12,000 common shares on October 10, 2025, under a pre-arranged Rule 10b5-1 trading plan.

Summary

• William D. Waddill, a Director of Protagonist Therapeutics, Inc. (PTGX), reported transactions on October 10, 2025.
• Waddill exercised stock options to acquire 12,000 shares of common stock at an exercise price of $6.98 per share.
• Concurrently, Waddill sold 4,000 shares at $69.25 per share.
• Additionally, Waddill sold another 8,000 shares at a weighted average price of $87.81 per share, with prices ranging from $86.71 to $88.00.
• These sales were conducted pursuant to a Rule 10b5-1 trading plan adopted on November 10, 2023.
• Following these transactions, Waddill's direct beneficial ownership of common stock decreased from 17,130 shares to 5,130 shares.
• The stock options exercised were fully vested and had an expiration date of May 28, 2028.

Sentiment

Score: 5

Explanation: The director's sale of shares, even under a Rule 10b5-1 plan, represents a reduction in direct beneficial ownership. While pre-planned sales are less concerning than opportunistic sales, a significant reduction in insider holdings can sometimes be perceived as a slight negative by the market. The substantial profit realized from the option exercise is a positive for the individual, but not directly for the company's operational outlook.

Positives

• The transactions were executed under a pre-arranged Rule 10b5-1 trading plan, indicating a planned sale rather than an immediate reaction to new, undisclosed information.
• The exercise price of the options ($6.98) is significantly lower than the sale prices ($69.25 and $87.81), indicating substantial personal gain for the director.

Negatives

• A director selling a significant number of shares (12,000 shares, representing the full amount acquired via option exercise) could be perceived negatively by investors, even if pre-planned.
• The total direct beneficial ownership of common stock decreased from 17,130 to 5,130 shares following these transactions.

Risks

• Investor perception of insider selling, even if pre-planned, could lead to negative sentiment or speculation about the company's future prospects.

Future Outlook

The filing does not contain any forward-looking statements or guidance regarding the company's future performance or strategic direction.

Management Comments

• The sales were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 10, 2023.
• The stock options exercised were fully vested.

Industry Context

This Form 4 filing reports an individual insider transaction and does not provide information directly related to broader industry trends or competitive landscape. However, insider selling activity in the biotechnology sector is often scrutinized for potential signals regarding company prospects, though pre-planned sales under Rule 10b5-1 are generally viewed as less indicative of negative sentiment.

Comparison to Industry Standards

• This filing details an insider transaction and does not contain information that allows for a direct comparison to industry-wide operational or financial benchmarks. Insider trading activity is typically evaluated against the company's own historical insider activity and general market sentiment towards insider transactions.

Stakeholder Impact

• Shareholders: May interpret the director's sale as a signal, potentially influencing their investment decisions.

Key Dates

Recommendation

While a director selling shares might typically be viewed negatively, these transactions were executed under a pre-arranged Rule 10b5-1 trading plan, which suggests the sales were not based on new, undisclosed material information. The director realized significant profits from the option exercise. Without additional financial or operational updates from Protagonist Therapeutics, this Form 4 alone does not provide enough information to change a fundamental investment thesis, thus a 'hold' recommendation is appropriate for existing investors, and 'na' for new investors as it's not a strong signal.

Keywords

Protagonist Therapeutics, PTGX, Insider Trading, Form 4, Stock Option Exercise, Share Sale, Director, William D. Waddill, Rule 10b5-1