The Securities and Exchange Commission (SEC) requires US issuers, that is, listed companies and securities, including mutual funds to file three quarterly financial statements (Form 10-Q) and one annual report (Form 10-K), in addition to various other regulatory filing requirements.

Since the early 1990s, the SEC made these filings available through its Electronic Data Gathering, Analysis, and Retrieval (EDGAR) system. They constitute the primary data source for the fundamental analysis of equity and other securities, such as corporate credit, where the value depends on the business prospects and financial health of the issuer.