In 2009, the SEC mandated that financial statements be filed using eXtensible Business Reporting Language (XBRL). The SEC contends that this new search-facilitating technology will reduce informational barriers that separate smaller, less-sophisticated investors from larger, more-sophisticated...

This study examines the effects of financial reporting complexity on investors' trading behavior. I find that more complex (longer and less readable) filings are associated with lower overall trading, and that this relationship appears due to a reduction in small investors' trading activity....