Form 4: Amylyx Co-CEO Exercises Options, Sells Shares

Amylyx Pharmaceuticals Co-CEO Justin Klee exercised stock options and subsequently sold a portion of the acquired shares to cover costs and tax obligations.

Summary

• Co-Chief Executive Officer and Director Justin B. Klee exercised stock options for a total of 200,000 shares of Amylyx Pharmaceuticals, Inc. common stock.
• The options were exercised at a price of $7.57 per share on January 15, 2026, and January 16, 2026.
• A total of 138,188 shares were sold to cover the option exercise cost and tax obligations.
• The shares were sold at weighted average prices of $13.5827 (for 136,193 shares) and $13.8853 (for 1,995 shares).
• These transactions were conducted pursuant to a preset sales plan adopted by the reporting person on November 12, 2025, under Rule 10b5-1(c).
• Following these reported transactions, Justin Klee directly beneficially owns 3,379,398 shares of common stock.

Sentiment

Score: 6

Explanation: The sentiment is neutral to slightly positive. While there's insider selling, it's for tax purposes and under a pre-arranged plan, which is a common and expected event. The executive still retains a significant number of shares, and the option exercise was profitable, indicating a higher stock price than the exercise price.

Positives

• The exercise price of $7.57 is significantly lower than the sale prices of $13.5827 and $13.8853, indicating a profitable transaction for the insider.
• The transactions were executed under a Rule 10b5-1 plan, suggesting a pre-planned, non-discretionary sale, which can reduce concerns about opportunistic insider selling.

Negatives

• An insider selling a substantial number of shares, even for tax purposes, could be perceived negatively by some investors, potentially signaling a lack of confidence, although this is mitigated by the 10b5-1 plan.

Future Outlook

No forward-looking statements or guidance are provided in this insider transaction report.

Industry Context

This filing reports routine insider transactions and does not provide information directly related to broader industry trends or competitive landscape. It reflects an individual executive's compensation-related activities.

Related Party Transactions

• The transactions involve the Co-Chief Executive Officer and Director of Amylyx Pharmaceuticals, Inc., exercising stock options and selling shares, which is a related party transaction by definition of insider trading rules.

Stakeholder Impact

• Shareholders may view the sale of shares by a key executive with mixed feelings; however, the pre-arranged nature (10b5-1 plan) and purpose (tax obligations) typically mitigate negative interpretations. The executive retains a substantial stake, aligning his interests with other shareholders.

Next Steps

• The remaining unexercised portion of the stock option is due to expire on February 19, 2026.

Key Dates

Recommendation

This Form 4 filing details a routine insider transaction involving the exercise of stock options and subsequent sale of shares to cover costs and taxes under a pre-arranged 10b5-1 plan. Such transactions are common and generally do not indicate a change in the company's fundamental outlook or the executive's long-term confidence. The executive retains a significant beneficial ownership. Therefore, based solely on this filing, a 'hold' recommendation is appropriate as it provides no new information to alter an existing investment thesis.

Keywords

Amylyx Pharmaceuticals, AMLX, Insider Trading, Form 4, Stock Options, Executive Compensation, Justin Klee, Rule 10b5-1