The initial statement of beneficial ownership for new corporate insiders.
Definition
Form 3 is a document submitted to the SEC by individuals who have newly become corporate insiders—such as a newly hired executive, a recently appointed board member, or an investor who just crossed the 10% ownership threshold. It must be filed within 10 days of becoming an insider.
Why it matters for Whale Tracking
Form 3 establishes the baseline of an executive's portfolio. Quantitative tracking models use Form 3 to know exactly how many shares an insider holds before they begin trading, making it possible to calculate the percentage impact of their future Form 4 purchases or sales.
Real-World Example
"When a new CFO is hired at Amazon (AMZN), they file a Form 3 declaring they currently own 0 shares. This initializes their profile in the database, ready to track their future equity grants and trades."