MTNB SCHEDULE 13D/A: Activist campaign
An amendment to a Schedule 13D was
Filed with the SEC on · accession 0000921895-26-002111
MTNB filed a SCHEDULE 13D/A (schedule 13d/a) with the SEC on Aug 13, 2026. An amendment to a Schedule 13D was filed regarding Matinas BioPharma Holdings, Inc., indicating a change in a previously reported activist or large shareholder position. The stock moved -2.9% by the first close after the filing.
Summary of the filing
An amendment to a Schedule 13D was filed regarding Matinas BioPharma Holdings, Inc., indicating a change in a previously reported activist or large shareholder position. The filing text does not disclose specific ownership percentages or stated intentions.
Key details
How MTNB stock reacted
Close before
$3.60
Aug 12, 2026
First close after
-2.92%
$3.50
5 trading days
+0.42%
$3.61
Since filing
-66.67%
$1.20
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Click hereFrequently asked questions
What did MTNB file with the SEC on Aug 13, 2026?
MTNB filed a SCHEDULE 13D/A (Activist campaign). An amendment to a Schedule 13D was filed regarding Matinas BioPharma Holdings, Inc., indicating a change in a previously reported activist or large shareholder position. The filing text does not disclose specific ownership percentages or stated intentions.
What does a activist campaign mean for MTNB stock?
A settlement removes uncertainty; the stock often reacts to whether the amount is bigger or smaller than investors expected.
How do I read a SCHEDULE 13D/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 13D/A (schedule 13d/a): A report the company filed with the SEC (the US market regulator).
How did MTNB stock react to this filing?
MTNB closed at $3.60 before the filing and $3.50 on Aug 13, 2026 (-2.92%). Five trading days later: $3.61 (+0.42%).
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