Form 3 is an SEC filing filed with the US Securities and Exchange Commission to indicate a preliminary insider transaction by an officer, director, or beneficial (10%) owner of the company's securities.
These are typically seen after a company IPOs when insiders make their first transactions.
After a Form 3 is filed, future filings of the same nature are filed under Form 4 (standard disclosure) or Form 5 (annual disclosure).
Form 3 is stored in SEC's EDGAR database and academic researchers make these reports freely available as structured datasets in the Harvard Dataverse.
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