8-K (Material Event)

An 8-K is a form that publicly traded companies must file with the SEC (the government agency that oversees stock markets) whenever something important happens that could affect the stock price. Think of it as a company's way of saying "Hey, investors, something significant just went down." You'll encounter 8-Ks when checking company news, and they matter because they're official announcements—not rumors or social media posts. Common triggers include executive departures, major lawsuits, acquisitions, or bankruptcy filings. For example, if TechCorp's CEO suddenly resigned, the company would file an 8-K within four business days. These filings help keep the playing field level so all investors get important information at roughly the same time.