Section 404 of The Sarbanes-Oxley Act of 2002 requires that companies document and test their internal control over financial reporting. And, of course, the standard that auditors use to gauge the success of those efforts is known as Audit Standard Number 2, issued by the Public Company Accounting Oversight Board in June 2004.

But the PCAOB’s AS No 2., officially called “An Audit of Internal Control Over Financial Reporting Conducted in Conjunction With an Audit of Financial Statements,” does not specify exactly how much testing is enough.