Illinois Proposed Addback Regulations Raise Questions On Clarity, Administrability

Breen Schiller, a Greenberg Traurig shareholder in the Chicago office, recently submitted formal comments to the Illinois Department of Revenue (IDOR or Department) and the Joint Committee on Administrative Rules (JCAR) regarding the Department’s proposed amendments to 86 Ill. Adm. Code Section 100.2430 – the regulation governing addbacks for interest and intangible expenses in transactions with 80/20 companies. In addition to submitting written comments, Schiller also testified at the subject matter hearing before the Department, offering recommendations regarding clarity and administrability in the rulemaking process. 

Key Issues Addressed 

• Conduit Exception Narrowing: The draft regulation imposes tracing requirements and prohibits reasonable fungibility, which may disqualify market-based financing and IP structures. This approach appears to depart from the statute’s original purpose of targeting tax-motivated base erosion – rather than arm’s-length, third-party costs. 

• “Unreasonable” Standard Limitations: For tax years ending on or after Dec. 31, 2025, the draft provides that it is not “unreasonable” to require addback solely because the foreign recipient is subject to a net income tax, the terms are arm’s length, or the principal purpose is not tax avoidance. This construction may limit the practical effect of the statutory safety valve and leave taxpayers without clear guidance. 

• Reliance on Private Letter Rulings (PLRs): The draft directs taxpayers to seek PLRs for relief. Because PLRs are publicly available, binding only on the requester, and unavailable for hypothetical transactions, this approach may present administrability challenges for common fact patterns and raises questions about confidentiality and predictability. 

Advocacy Highlights 

• Schiller recommended that the Department consider a workable conduit framework that allows reasonable fungibility and allocation methodologies where contemporaneous documentation shows external third-party financing economically supports the intercompany arrangement. 

• Schiller recommended reinstating core commercial factors – arm’s-length terms, absence of tax-avoidance purpose, and foreign net-income taxation – as affirmative factors in the unreasonableness analysis. 

• Schiller called for balanced, quantitative examples reflecting relief in common scenarios, and for the creation of a documentation safe harbor to guide compliant taxpayers and reduce controversy. 

• Schiller emphasized the need for a workable alternative procedure through which taxpayers may request guidance on whether they qualify for the unreasonable exception, in lieu of a PLR. 

The proposed amendments raise questions about administrability and the potential for double taxation and may create uncertainty for Illinois businesses. Schiller’s comments and testimony address potential concerns regarding clarity and administrability within the framework.