The U.S. Securities and Exchange Commission is embarking on a much needed reform of public-­company disclosure rules, largely to answer a simple yet critical question: What type of information do investors really want to make informed investment decisions?

Of course, it’s a question often asked by commissioners and staff. The SEC’s charge is to ensure that investors receive material information about public companies in a timely manner. But the commission’s point is to determine whether the amount of information available to investors can be streamlined, not expanded.