A recent summons showdown with UBS shows that DOJ and the IRS are far from done with offshore enforcement efforts, and are expanding those efforts beyond Europe. Among the most likely of new targets is Singapore, and since there is no Tax Information Exchange Agreement (TIEA) or other tax treaty between the United States and Singapore, foreign financial institutions could see IRS summonses being served on their U.S. branches.

Such summonses often are referred to as Bank of Nova Scotia summons. In the recent case involving UBS, the IRS served a third-party summons on a branch of UBS AG in the United States seeking records for an account at UBS in Singapore held by a U.S. citizen living in Hong Kong UBS refused to turn over the records on grounds that Singapore's bank secrecy laws prohibited disclosure without permission from the accountholder. The IRS sought to enforce the summons in federal court – and the case was teed up for litigation – until the accountholder consented to release of the records and UBS complied with the summons. The IRS thereafter withdrew the enforcement action.

We cannot know whether UBS or the government ultimately would have won the day in court. Many factors are taken into consideration in such enforcement actions, and past cases have had varied results. What we do know is that the government maintains the summons served on UBS was enforceable, and was willing to go the distance. With Singapore – and potentially other jurisdictions without TIEA's or tax treaties – on the enforcement horizon, more global financial institutions are likely to see IRS summonses coming their way.

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