Stuart E. Seigel told corporate tax officials attending the annual Tax Executives Institute conference that FIN 48, the FASB ruling requiring public companies to provide greater transparency and information about their tax positions and reserves, has created a great deal of ambiguity as to how it will be implemented with respect to Securities and Exchange Commission and IRS procedures and enforcement and how it will be used by investors and analysts.

"It is clear that we will be living in a world of uncertainty for some time to come as the consequences of FIN 48 play out," Seigel said. "The SEC's role in all this is going to be significant, even though not much of consequence in that arena has yet occurred."

He said potential restatement issues revolving around tax reserves remain unresolved, and told the audience to keep in mind the "severe consquences" of restatements as they adopt procedures to comply with FIN 48.

Seigel, now chairman and CEO of Seigel & Associates, LLC, said FIN 48 is only the beginning of a trend mandating greater corporate tax transparency and disclosure, noting that the information FIN 48 will make publicly available will open up new areas of interest and concern by regulators, investors, financial and tax reporters and stock analysts.

"Corporate tax and financial managers need, as a matter of priority, to keep those issues in mind and, beyond proper technical compliance with the strictures of FIN 48, be alert to its ramifications," Seigel said.