The European Union recently mandated the rotation of auditors for public companies.  The ruling requires a rotation after 10 years, although there are ways for companies to extend the rotation period, including putting the audit contract out to bid, even if the incumbent firm is chosen again.  European Internal Market and Services Commissioner Michel Barnier was quoted as saying “These new measures will reduce risks of excessive familiarity between statutory auditors and their clients, encourage fresh thinking, and limit conflicts of interest".  

Additionally, there are additional reporting requirements as a result of the audit process, including the requirement to provide a detailed to the company's audit committee that is not necessarily intended for public disclosure.