Here's another number – Years. Feel free correct any mistakes or add to the list. Could put the numbers together in order, but these are sorted by topic. Hope it helps!
7 Years: Audit Documentation (Working Papers) must be kept for 7 years for public company audits (issuers).
5 Years: Audit Documentation must be kept for 5 years for other audits (non-issuers).
5 Years: SOX/PCAOB/SEC rules require the audit lead partner and review auditor to rotate every 5 years. They are also subject to a five-year time out period before returning to the engagement. (5 and 5)
7 Years: All other audit partners (excluding the lead partner and reviewing partner) must rotate off the audit every seven years and are subject to a two-year time-out period (7 and 2).
7 Years: IFAC Code of Ethics requires that the lead and engagement quality review partners on public company audits rotate after no more than seven years
1 Year: Cool-off period. Per SOX, audit firms may not audit public companies whose CEO, CFO, etc., is also a previous employee of the accounting firm who worked on the audit during the preceding year.
Annually: Under SOX Section 104, firms that audit more than 100 issuers are inspected annually.
Every 3 Years: Under SOX Section 104, firms that audit 100 or fewer issuers are inspected every three years
Every 3 Years: Every audit firm performing audits in accordance with GAGAS have an external peer review every 3 years. Also must establish a system and maintain a system of quality control.
Every 3 Years: Peer review occurs when one CPA firm reviews another CPA firm's compliance with its quality control system. A CPA firm that is a member of the AICPA must have a peer review every three years in order to maintain membership in the AICPA.
Annually: At least annually, all firm personnel subject to independence requirements should confirm their independence in writing (paper or electronic form).
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