This CFO.com article discusses the process of having to go back and re-state or re-work a company's financial statements. The article details the effect that such changes can have on past statements as well as the SEC implications that can be involved.

As a result of this work, Nortel is reviewing accruals and provisions of prior periods, which will likely require it to revise its results for the 2003 calendar year, several of its 2003 quarterly reports, and financial results for prior periods, according to the company. Given the volume and complexity of the work involved, company management can't predict when the review will be completed, Nortel stated.