Close the Round-Tripping Loophole Act

This bill amends U.S. tax law to close a loophole allowing companies to artificially shift profits between U.S. and foreign subsidiaries to reduce taxes. It directly affects U.S. corporations with foreign subsidiaries that engage in "round-tripping" - moving profits through transactions involving U.S.-sold property or services without proper documentation of foreign use. The key mechanism creates a "round-tripping ratio" that reduces tax benefits for profits tied to these practices by calculating the percentage of income derived from such transactions relative to total foreign income. Small businesses with average annual gross receipts under $100 million are exempt from this calculation. The changes apply to tax years beginning after the bill's enactment.