Tax Cuts and Jobs Act: Future Rulemaking Should Provide Greater Detail on Paperwork Burden and Economic Effects of International Business Provisions, Report to the Chairman, Committee on Finance, U.S. Senate [open pdf - 1MB]
From the Highlights: "TCJA [Tax Cuts and Jobs Act of 2017] made sweeping changes to taxing U.S. corporations' international activities: (1) a transition tax on untaxed overseas earnings of foreign subsidiaries that accrued prior to 2017; (2) a tax on the net income earned by foreign subsidiaries exceeding a specified threshold of certain assets; (3) a deduction for income from certain foreign-derived sales of property or services exceeding a specified threshold of certain assets; and (4) a tax on certain payments made to a related foreign party referred to as base erosion payments. GAO [Government Accountability Office] was asked to review IRS [Internal Revenue Service]'s implementation of TCJA and early effects of the law. This report: (1) describes how TCJA's international provisions may be affecting U.S.-based corporations' international business activities; and (2) assesses IRS's and Treasury's development of relevant regulations and guidance to implement the provisions. GAO interviewed representatives from eight companies' tax departments randomly selected from among the 100 largest U.S.- based companies and compared relevant regulations and guidance against procedural requirements."
Government Accountability Office: http://www.gao.gov/