Andy Howlett and David Zimmerman commented on what tax practitioners hope the government will address in its final rules on the Tax Cuts and Jobs Act's (TCJA's) new limits on business interest expense deductions, which are expected to be released in the coming weeks. The TCJA changed Section 163(j) to cap the deduction for net business interest expenses at 30 percent of adjusted taxable income, and the definition of interest "was so broad it caught a lot of people by surprise," Zimmerman said. "My hope is that [at] least in some cases, [the government] might narrow the scope of what is business interest," he added.

The proposed regulations also create a mandatory 11-step process to determine the allocation of allowable business interest deductions and related attributes incurred by a partnership to its partners. According to Howlett, there is broad agreement among practitioners that these steps are correct as a technical matter in reaching proper results, but the rules are quite complex and require a complete separate method of accounting from the partnership's usual partnership allocations. The American Bar Association has advocated for the government to also provide a reasonable approach method, in the hope "that they'd give taxpayers the option, instead of using the 11-step rules, to allocate the 163(j) items of those partners in any method that is reasonable and is consistent with the intent of the statue and regulations," Howlett said.