Form 4: Mirum CEO Peetz Reports RSU Vesting & Tax-Related Sale

Mirum Pharmaceuticals CEO Christopher Peetz reported the vesting of restricted stock units and a subsequent sale of shares to cover tax obligations.

Summary

• Christopher Peetz, CEO and Director of Mirum Pharmaceuticals, Inc. (MIRM), reported transactions involving the company's common stock.
• On January 23, 2026, 12,500 shares of common stock were acquired upon the vesting of restricted stock units.
• On January 26, 2026, 6,831 shares of common stock were sold at a price of $96.192 per share.
• The sale of shares was conducted to cover tax withholding obligations associated with the vesting of the restricted stock units.
• Following these transactions, Peetz directly beneficially owns 169,402 shares of common stock.
• Additionally, The Peetz Family Trust indirectly beneficially owns 187,500 shares of common stock.
• The transactions were made pursuant to a Rule 10b5-1(c) plan.

Sentiment

Score: 6

Explanation: The filing reports routine insider transactions related to executive compensation (RSU vesting and tax-related sale). While there's a net reduction in direct shares, it's for an expected purpose and does not indicate a negative sentiment from the insider. The overall beneficial ownership remains substantial.

Positives

• The vesting of 12,500 restricted stock units indicates continued compensation and retention of the CEO.
• The transactions were conducted under a Rule 10b5-1(c) plan, suggesting pre-planned and not opportunistic trading.

Negatives

• A net reduction of 6,831 shares in direct beneficial ownership due to the tax-related sale.

Future Outlook

No specific future outlook is provided beyond the established vesting schedule for restricted stock units, where 1/3rd of the shares vest on each anniversary of January 23, 2024, until the three-year anniversary.

Industry Context

This is an individual insider transaction reflecting standard executive compensation practices within the biotechnology and pharmaceutical industry, where restricted stock units are a common component of executive pay. It does not directly relate to broader industry trends or competitive dynamics.

Related Party Transactions

• The reported transactions involve the CEO, Christopher Peetz, and Mirum Pharmaceuticals, Inc., which are inherently related party transactions as defined by SEC regulations for insider reporting.

Stakeholder Impact

• Shareholders: Provides transparency into executive compensation and insider ownership changes. The tax-related sale is a routine event and unlikely to significantly impact shareholder sentiment.
• Employees: Reflects standard executive compensation practices.

Next Steps

• Remaining restricted stock units will continue to vest on each anniversary of January 23, 2024, until the three-year anniversary.

Key Dates

Recommendation

This Form 4 details routine insider transactions related to executive compensation, specifically the vesting of restricted stock units and a subsequent sale to cover tax obligations. Such transactions are common and pre-planned under a 10b5-1 plan, indicating no change in the insider's fundamental view of the company. It does not provide new information that would warrant a change in investment thesis, thus a 'hold' recommendation is appropriate.

Keywords

Mirum Pharmaceuticals, MIRM, Christopher Peetz, CEO, Director, SEC Form 4, Insider Trading, Restricted Stock Units, RSU Vesting, Stock Sale, Tax Withholding, 10b5-1 Plan