SCHEDULE: Metsera Acquired by Pfizer; ARCH Ventures Exits Stake

ARCH Venture Funds and associated individuals ceased to be 5% beneficial owners of Metsera, Inc. following its acquisition by Pfizer Inc. for $65.60 cash per share plus a contingent value right.

Summary

• Metsera, Inc. was acquired by Pfizer Inc. through a merger with Mayfair Merger Sub, Inc., a wholly-owned subsidiary of Pfizer Inc.
• Metsera, Inc. now operates as a wholly-owned subsidiary of Pfizer Inc.
• Each outstanding share of Metsera common stock was converted into $65.60 cash per share, without interest and net of applicable withholding taxes.
• Shareholders also received one contractual contingent value right (CVR), entitling them to potential future cash payments upon the achievement of certain specified milestones.
• The reporting persons, including ARCH Venture Fund XII, L.P., ARCH Venture Fund XIII, L.P., and associated entities and individuals, ceased to be beneficial owners of 5% or more of Metsera's Common Stock as of November 13, 2025.

Sentiment

Score: 7

Explanation: The filing reports the successful completion of a merger for Metsera, Inc., resulting in a cash payout and CVRs for shareholders, including the reporting persons. This represents a successful exit for the venture capital funds, indicating a positive outcome for their investment.

Positives

• Reporting persons received a significant cash consideration of $65.60 per share for their Metsera, Inc. common stock.
• The inclusion of contingent value rights (CVRs) provides an opportunity for additional future payments based on the achievement of specific milestones.
• The transaction represents a successful exit for the ARCH Venture Funds and associated individuals from their investment in Metsera, Inc.

Negatives

• Reporting persons no longer hold direct equity in Metsera, Inc., thereby losing direct exposure to the company's future growth and potential appreciation beyond the CVR terms.

Future Outlook

The filing details the completion of a past event (the merger) and its impact on the reporting persons' ownership. It does not provide a future outlook for Metsera, Inc. or Pfizer Inc., other than the mechanism for potential future payments via contingent value rights tied to specific milestones.

Industry Context

This acquisition by Pfizer Inc. of Metsera, Inc. is consistent with the ongoing trend of large pharmaceutical companies acquiring smaller biotechnology firms to expand their pipelines and intellectual property portfolios. Such mergers often involve a combination of upfront cash and contingent value rights to mitigate risk and incentivize future performance.

Comparison to Industry Standards

• The acquisition of a biotech company by a major pharmaceutical firm like Pfizer is a common industry practice for pipeline expansion.
• The use of Contingent Value Rights (CVRs) in M&A transactions, particularly in the biotech and pharmaceutical sectors, is a standard mechanism to bridge valuation gaps and share future risks/rewards, often tied to clinical trial success or regulatory approvals.
• Specific comparable companies or projects are not mentioned in the filing, but similar deals include Bristol Myers Squibb's acquisition of Celgene (which also included CVRs) or Gilead Sciences' acquisition of Immunomedics.

Stakeholder Impact

• Shareholders (Metsera): Received $65.60 cash per share and one CVR, converting their equity into a defined payout structure.
• Pfizer Inc.: Successfully acquired Metsera, Inc., expanding its portfolio.
• ARCH Venture Funds: Successfully exited their investment in Metsera, Inc.

Next Steps

• Achievement of specified milestones for the contingent value rights to trigger additional payments.

Key Dates

Keywords

Metsera Inc., Pfizer Inc., Merger, Acquisition, ARCH Venture, Schedule 13D, Common Stock, Contingent Value Right, CVR, Biotechnology, Pharmaceuticals, Venture Capital Exit