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SEC Filings

Schedule 13D

A form filed when an investor acquires more than 5% of a company with active intentions.

Definition

Often called a 'beneficial ownership report,' Schedule 13D must be filed with the SEC within 10 days after an entity acquires more than 5% of any class of a company's shares, provided they intend to actively influence the management or control of the company.

Why it matters for Whale Tracking

13D filings are the bat-signal of activist investing. They alert the market that a 'whale' has arrived and intends to force changes—like firing the CEO, selling divisions, or pushing for a buyout—which almost always causes high stock volatility.

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Technical Nuance

Schedule 13D is a critical tool for identifying activist investors and their intentions. The form requires detailed disclosures about the purpose of the acquisition, the source of funds, and any plans to influence the company's management. This information can provide valuable insights into potential corporate actions that may affect the stock's performance.

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Real-World Example

"If Carl Icahn quietly buys 6% of a struggling tech firm, he must drop a Schedule 13D. Algorithmic news feeds instantly blast this out, and the stock price typically surges as retail and institutional money follow his lead."

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