The United States first issued a summons for approximately 52,000 names in July of 2008, which the Swiss blocked.
A settlement was then reached in August of 2009, when the United States agreed to give up its right to all 52,000 names in exchange for getting prompt access to key account holders, which totaled 4,450.
"Now the Swiss, despite multiple U.S. concessions and having strung out the UBS case for 2 years, have failed to live up to their end of the bargain," Levin said. "The United States should reject any further attempts by the Swiss to delay the UBS case. It is time to move forward with the summons in court and force UBS to provide the names and account information for all 52,000 suspected U.S. tax cheats."
UBS has recently admitted helping U.S. taxpayers hide money from taxation and for quite a while it has faced pressure from the United States to give up the names of U.S. account holders. UBS recently agreed to hand over some names and pay a $780 million penalty in return for its prosecution being deferred.