"The proposed rules address a one-time transition tax on post-1986, untaxed foreign earnings of specific foreign corporations owned by US shareholders," a press release announcing the regulations said. "Generally, the transition tax can be paid in installments over an eight-year period."
The Tax Cuts and Jobs Act treats these foreign earnings as repatriated and places a 15.5 percent tax on cash or cash equivalents, the release explained.
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Prior to the tax-reform law approved late last year, US companies held an estimated $4 trillion in overseas earnings in offshore accounts, presumably to avoid paying a 35 percent tax then in effect, according to published reports.