Using the U.S. Securities and Exchange Commission's mandate of eXtensible Business Reporting Language (XBRL) as a natural experiment, this study investigates whether and how the decreased information‐processing costs brought about by XBRL influence firms’ breadth of share ownership. We find that the XBRL mandate is associated with an increase in the total number of a firm's shareholders. This finding is consistent with the notion that XBRL facilitates a more transparent environment and decreases information‐processing costs, thereby attracting more shareholders in general. More interestingly, we find that while XBRL adoption is associated with an increase in share ownership of individual and non‐U.S. foreign institutional investors, it is associated with a decrease in share ownership of U.S. domestic institutional investors. Further evidence shows that this asymmetric shift in share ownership is more pronounced for more complex firms. Our findings, taken together, suggest that the decreased information‐processing costs brought about by XBRL help firms establish a level playing field by reducing the information disadvantages of individual and foreign institutional investors over domestic institutional investors. Our results are robust to potential endogeneity concerns and alternative research designs.

We exploit the technological closeness among clients of the same auditor to examine whether auditors accumulate knowledge from their clients’ technological proximity. We find that a client firm’s technological proximity to other clients of its audit office improves audit quality and results in an audit fee discount, even after controlling for the product similarity effect, auditors’ overall technological expertise, and industry specialization. Both an increase in audit quality and a decrease in audit fees occur if a client firm exhibits greater technological similarity to clients of other audit offices within the same audit firm. Our findings suggest that the auditors’ technological proximity knowledge enhances the effectiveness and efficiency of audit work at both the audit firm and audit office levels. Data Availability: Data are available from the public sources cited in the text.