The Internal Revenue Service's final rule targeting potentially abusive microcaptive insurance structures is facing a renewed legal challenge in the 6th Circuit Court of Appeals, continuing a multi-year regulatory battle with significant implications for small business captive owners and their advisors across the US.
Plaintiff CIC Services LLC, a Knoxville, Tennessee-based firm that helps small and mid-sized businesses form and manage captive insurance companies, is appealing a March 2026 ruling from the US District Court for the Eastern District of Tennessee that found the IRS acted within the authority of the Administrative Procedure Act when issuing the final rule.
The IRS issued its final regulations on Jan. 14, 2025, classifying certain microcaptive transactions as either listed transactions or transactions of interest, both of which carry mandatory disclosure obligations for all parties involved. The rule targets Section 831(b) captives, small insurance companies that elect to be taxed only on investment income rather than underwriting profit.
Microcaptives can exclude up to $2.85 million in annual premiums from taxable income under the 2025 rules, a figure raised to $2.9 million for 2026 under the IRS's annual inflation adjustment. When properly structured, they allow privately held businesses to manage risks, stabilize premiums and retain underwriting profits. The IRS's concern is that the same tax advantages have also been exploited by arrangements that lack genuine insurance substance.
The final rule designates a captive as a listed transaction if the insured entity owns at least 20% of the captive and the loss ratio falls below 60%, or the transaction did not generate taxable income for premium recipients during the past five years. A transaction of interest designation applies at a 65% loss ratio threshold.
Penalties for failing to disclose a listed transaction are set at 20% under IRC Section 6662(b)(6), rising to 40% if the transaction is not properly disclosed. Material advisors, including captive managers, attorneys and accountants who advise on these structures, face separate disclosure obligations and their own penalty exposure under Section 6707(a).
This is not CIC Services' first confrontation with the IRS. The firm previously won a unanimous Supreme Court decision in 2021 establishing that federal courts could review and block unlawful IRS rules. That case centered on IRS Notice 2016-66, which courts later ruled was issued without required rulemaking procedures. The IRS subsequently conducted formal notice-and-comment rulemaking before issuing the 2025 final rule, which CIC Services is now challenging on different grounds.
The appeal unfolds against a backdrop of conflicting federal court rulings. The Eastern District of Tennessee upheld the rule, finding it creates disclosure requirements rather than substantive tax rules. Two Texas courts reached different conclusions. The Southern District of Texas vacated the listed-transaction designation, finding the IRS had failed to show that the covered transactions are predominantly tax-avoidance schemes, while upholding the transactions of interest designation. The Northern District of Texas refused to dismiss a lawsuit arguing both designations are arbitrary and capricious, ruling that plaintiffs had shown the rule lacked sufficient underlying data.
The divergence across three district courts sets up the 6th Circuit as a potentially determinative venue for the captive insurance industry.
The case arrives as the broader captive insurance market is expanding. Marsh-managed captives wrote $79.1 billion in gross written premium in 2025, with 118 new captive formations recorded that year. Vermont remains the largest US domicile with 683 licensed captives, and more than 30 states now have captive laws in place. Activity in 2025 was driven by sustained demand in medical stop-loss, cyber lines and commercial auto, with captive managers reporting that organizations of all sizes are increasingly turning to captives amid hardening commercial markets for liability, property and cyber coverage.
For microcaptive owners, the litigation carries immediate practical consequences. The disclosure regime created by the final regulations remains in effect and enforceable while appeals proceed, meaning qualifying microcaptive arrangements must be properly identified, documented and reported or face significant penalties and expanded IRS scrutiny.
Revenue Procedure 2025-13 provides a streamlined process for captives to revoke their Section 831(b) election if owners determine the compliance burden outweighs the benefits. The IRS has made clear, however, that revocation does not eliminate its ability to scrutinize prior arrangements for insurance validity, premium appropriateness and economic substance.
CIC Services is asking the 6th Circuit to overturn the Eastern District of Tennessee's decision and remand the case with instructions to vacate the rule. The IRS declined to comment on the pending appeal.
