Alnylam (ALNY) CSO Vesting Triggers 2,851 Shares; Sell-to-Cover of 1,396 Shares
Rhea-AI Filing Summary
Kevin J. Fitzgerald, CSO & EVP, Head of Research at Alnylam Pharmaceuticals (ALNY), reported insider transactions tied to vested performance-based awards. On 08/15/2025 he was issued 2,851 shares following vesting of 30% of a performance-based stock unit granted 03/01/2024 after a clinical milestone determination. On 08/18/2025 he sold a total of 1,396 shares via multiple transactions under a mandatory sell-to-cover provision to satisfy tax withholding, at weighted sale prices ranging roughly between $447.53 and $456.00 per share. Following these transactions he beneficially owned 23,515 shares directly and an additional 537 shares indirectly through a managed account.
Positive
- Performance milestone achieved: 2,851 shares issued upon vesting of 30% of a PSU after a clinical milestone determination on 08/15/2025
- Significant continued ownership: Reporting person retains 23,515 shares directly and 537 shares indirectly, maintaining alignment with shareholders
Negative
- Insider share sales: 1,396 shares sold on 08/18/2025 across multiple tranches at weighted prices roughly $447.53–$456.00, reducing direct holdings
- Tax-driven liquidity: Sales executed under mandatory sell-to-cover provision, indicating proceeds used for withholding obligations (reduces vested-share retention)
Insights
TL;DR: Insider received PSU shares after a clinical milestone and executed sell-to-cover transactions for tax obligations; activity appears administrative rather than a directional signal.
The reporting person was granted a performance-based stock unit that vested in part upon a clinical milestone, triggering issuance of 2,851 shares on 08/15/2025. The subsequent sales on 08/18/2025 (totaling 1,396 shares) were executed under a mandatory sell-to-cover provision, which is a routine mechanism to satisfy tax withholding on vesting events. The filings clearly disclose weighted-average price ranges for the multiple sale tranches and show continued meaningful ownership (23,515 direct shares plus 537 indirect). From a governance perspective, this is a common post-vesting liquidity action and is not, by itself, evidence of change in insider conviction.
TL;DR: The vesting reflects achievement of a corporate clinical milestone; sell-to-cover proceeds reduced share count modestly while leaving substantial insider ownership.
The 2,851-share issuance indicates a performance metric was met as of the committee determination on 08/15/2025. Sales on 08/18/2025 aggregated 1,396 shares across multiple price bands (weighted averages reported per tranche between approx. $447.53 and $456.00). Post-transactions direct beneficial ownership remained at 23,515 shares, with 537 shares held indirectly in a managed account, preserving insider alignment with shareholders. The pattern—vesting followed by sell-to-cover—aligns with compensation tax mechanics rather than opportunistic cashing out.
Insider Trade Summary
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock | 39 | $447.98 | $17K |
| Sale | Common Stock | 90 | $449.92 | $40K |
| Sale | Common Stock | 39 | $450.92 | $18K |
| Sale | Common Stock | 103 | $451.99 | $47K |
| Sale | Common Stock | 329 | $452.96 | $149K |
| Sale | Common Stock | 543 | $454.04 | $247K |
| Sale | Common Stock | 241 | $454.84 | $110K |
| Sale | Common Stock | 12 | $455.82 | $5K |
| Grant/Award | Common Stock | 2,851 | $0.00 | -- |
| holding | Common Stock | -- | -- | -- |
Footnotes (1)
- On March 1, 2024, the reporting person was granted a performance-based stock unit (PSU) under the 2018 Stock Incentive Plan. The shares subject to the PSU vest based on the achievement of three specified performance measures. The shares reported were issued to the reporting person upon vesting of thirty (30) percent of the shares subject to the PSU based on the achievement of a clinical milestone, as determined by The People, Culture and Compensation Committee of the Issuer Board of Directors on August 15, 2025. 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 required to cover minimum statutory tax withholding obligations that became due upon the vesting and settlement of a tranche of restricted stock units granted to the reporting person on March 1, 2024. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $447.53 to $448.45. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $449.21 to $450.16. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $450.42 to $451.39. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $451.48 to $452.48. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $452.49 to $453.49. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $453.50 to $454.45. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $454.58 to $455.55. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The price reported represents the weighted average sales price of shares sold in multiple transactions at prices ranging from $455.65 to $456.00. The reporting person will provide to the issuer, any security holder of the issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. Reflects shares of ALNY common stock acquired by the Reporting Person under the issuer 401(k) plan as a result of the issuer 401(k) matching contribution program.
