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INSM SCHEDULE 13G/A: SEC filing

An institutional holder

Filed with the SEC on · accession 0000902664-26-003527

INSM filed a SCHEDULE 13G/A (schedule 13g/a) with the SEC on Aug 14, 2026. An institutional holder filed an amended Schedule 13G for Insmed Inc, indicating a change in passive ownership position. The stock moved -2.1% by the first close after the filing.

Summary of the filing

An institutional holder filed an amended Schedule 13G for Insmed Inc, indicating a change in passive ownership position. The filing does not disclose a specific activist intent or material corporate event.

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Key details

IssuerInsmed Inc

How INSM stock reacted

Close before

$126.33

Aug 13, 2026

First close after

-2.05%

$123.74

5 trading days

-0.98%

$125.09

Since filing

-11.29%

$112.06

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Frequently asked questions

What did INSM file with the SEC on Aug 14, 2026?

INSM filed a SCHEDULE 13G/A (SEC filing). An institutional holder filed an amended Schedule 13G for Insmed Inc, indicating a change in passive ownership position. The filing does not disclose a specific activist intent or material corporate event.

How do I read a SCHEDULE 13G/A?

A report the company filed with the SEC (the US market regulator). Start with the summary, then the key amounts and names. Compare it with the company’s earlier filings.

Why are SEC filings important?

Public companies must tell the SEC about anything that can change their value — results, leadership changes, big deals, new shares, bankruptcy. Filings are the official source, often before the news. A SCHEDULE 13G/A (schedule 13g/a): A report the company filed with the SEC (the US market regulator).

How did INSM stock react to this filing?

INSM closed at $126.33 before the filing and $123.74 on Aug 14, 2026 (-2.05%). Five trading days later: $125.09 (-0.98%).

Other INSM SEC filings

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