Form 4: Alnylam Exec Sells Shares for Tax, 10b5-1 Plan

Alnylam Pharmaceuticals' CSO & EVP, Kevin Fitzgerald, reported sales of common stock totaling 1,291 shares for tax obligations and under a pre-arranged 10b5-1 trading plan.

Summary

• Kevin Joseph Fitzgerald, CSO & EVP, Head of Research at Alnylam Pharmaceuticals, Inc. (ALNY), reported transactions involving the sale of company common stock.
• A total of 1,291 shares of common stock were sold across multiple transactions on March 4, 2026, and March 5, 2026.
• The sales were executed at weighted average prices ranging from $318.27 to $326.40 per share.
• A portion of the sales (633 shares on March 4, 2026) was for mandatory sell-to-cover provisions to satisfy statutory tax withholding obligations upon the vesting of restricted stock units.
• Another portion of the sales (658 shares on March 5, 2026) was made pursuant to a Rule 10b5-1(c) trading plan adopted by Mr. Fitzgerald on August 14, 2025.
• Following these transactions, Mr. Fitzgerald directly beneficially owns 20,569 shares and indirectly owns 537 shares through a managed account, totaling 21,106 shares.

Sentiment

Score: 5

Explanation: StockSavvy.ai views this as a neutral event. The sales are attributed to routine tax obligations and a pre-established trading plan, which typically do not reflect a change in the executive's sentiment towards the company's prospects.

Positives

• The sales were primarily for tax withholding obligations and under a pre-arranged 10b5-1 trading plan, indicating planned, non-discretionary transactions rather than a change in sentiment.
• Mr. Fitzgerald retains a significant direct and indirect beneficial ownership of 21,106 shares in the company.

Negatives

• The filing reports sales of common stock by a key executive, which reduces their direct ownership stake.

Future Outlook

This filing does not contain any forward-looking statements or guidance regarding the company's future outlook.

Management Comments

• Represents shares automatically sold by the Company on behalf of the reporting person pursuant to a mandatory sell-to-cover provision in the award agreement to cover minimum statutory tax withholding obligations upon the vesting of restricted stock units.
• This transaction was made pursuant to a Rule 10b5-1(c) trading plan adopted by the Reporting Person on August 14, 2025.

Industry Context

StockSavvy.ai notes that routine insider sales for tax purposes or under pre-arranged 10b5-1 plans are common across the biotechnology and pharmaceutical industries, particularly for executives receiving equity compensation. These types of transactions typically do not signal a change in company fundamentals or executive confidence, unlike discretionary open-market sales.

Stakeholder Impact

• Shareholders: Minimal direct impact as these are routine, non-discretionary sales. The executive retains a substantial stake.
• Employees: No direct impact mentioned.
• Customers: No direct impact mentioned.
• Suppliers: No direct impact mentioned.
• Creditors: No direct impact mentioned.

Key Dates

Recommendation

The reported insider sales are routine, driven by tax obligations on vested equity and a pre-scheduled 10b5-1 trading plan. These transactions do not suggest a change in the company's fundamental outlook or the executive's long-term confidence. Therefore, a 'hold' recommendation is appropriate, as this filing provides no new information to alter an existing investment thesis.

Keywords

Alnylam Pharmaceuticals, ALNY, Form 4, insider trading, stock sale, Kevin Fitzgerald, 10b5-1 plan, restricted stock units, tax withholding