SCHEDULE 13G/A: Janus Henderson Group PLC Amends Stake in Mirum Pharmaceuticals, Holding 9.7% of Common Stock

Janus Henderson Group PLC has filed an Amendment No. 4 to its Schedule 13G, disclosing a beneficial ownership of 9.7% in Mirum Pharmaceuticals, Inc. as of March 31, 2025.

Summary

• Janus Henderson Group PLC, a Jersey-based holding company and investment adviser, has filed an Amendment No. 4 to its Schedule 13G regarding its beneficial ownership in Mirum Pharmaceuticals, Inc.
• As of March 31, 2025, Janus Henderson Group PLC beneficially owns an aggregate of 4,775,375 shares of Mirum Pharmaceuticals, Inc. Common Stock.
• This ownership represents 9.7% of the class of securities.
• The shares are held with shared voting power and shared dispositive power.
• The filing indicates that the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing the control of the issuer.

Sentiment

Score: 5

Explanation: The document is a factual report of beneficial ownership, providing neutral information without expressing positive or negative sentiment about the issuer's performance or outlook.

Risks

• The filing explicitly states that the securities were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer, indicating a passive investment stance.

Future Outlook

NA

Industry Context

This filing is a standard disclosure of a significant passive ownership stake by an investment firm in a pharmaceutical company. It reflects an investment decision by Janus Henderson Group PLC, rather than a strategic operational update from Mirum Pharmaceuticals, Inc. itself. Such filings are common for large institutional investors managing diversified portfolios.

Stakeholder Impact

• Shareholders: Provides transparency regarding a significant institutional investor's stake, which can influence market perception and liquidity.
• Investment Professionals: Offers insight into the holdings of a major investment firm, potentially informing their own investment strategies.

Key Dates

Keywords

Mirum Pharmaceuticals, Janus Henderson Group PLC, Schedule 13G, Beneficial Ownership, Common Stock, Investment Adviser, Holding Company, SEC Filing, MRM