Companies that issue securities are required to file periodically with the Securities and Exchange Commission. Many types of filings are required, but the most frequently used by investors are
Electronic filing was introduced in 1994. The Library collected filings on microfiche beginning in 1969.
Annual reports to shareholders are not required by the SEC, but are still issued by most companies. They generally feature a letter from the chief executive officer and a summary of the year's events. Financial results are included, but may not be as extensive as those filed in form 10-K. Annual reports are very good for researching how a company is presenting itself.