Law360 has 2026 “top” lists for tax cases and policies across three jurisdictional levels: federal, international, and state and local.
Highlights include litigation over the limited partner exception from self-employment taxes, implementation of the U.S. book minimum tax and the new Pillar 2 “side-by-side” agreement, and perennial bipartisan aspirations involving crypto.
All six lists, below the fold.
Kat Lucero, Top Federal Tax Cases to Watch in 2026, Law360 (Jan. 2, 2026):
The application of self-employment taxes to limited partners, the economic substance doctrine’s threshold and whether Internal Revenue Service penalties need a jury’s deliberation are topics federal courts likely will examine in coming decisions.
Stephen K. Cooper, Federal Tax Policy to Watch in 2026, Law360.com (Jan. 2, 2026):
That trend [of limited tax changes in midterm election years] is likely to continue in 2026, tax experts predict, despite growing calls for targeted relief in specific areas, including cryptocurrency taxation, the corporate book minimum tax, technical corrections to the GOP budget law, international tax, affordable housing incentives and healthcare-related provisions.
Natalie Olivo, Top International Tax Cases to Watch in 2026, Law360.com (Jan. 2, 2026):
Courts will be grappling with several key cases this year, including Coca-Cola’s long-running $2.7 billion transfer pricing dispute and pharmaceutical giant McKesson’s challenge to regulations it claims are statutorily invalid in allowing the Internal Revenue Service to allocate income from overseas. In addition, the U.S. Tax Court for the third time will weigh in on healthcare technology company Medtronic’s long-running dispute over how to price intangibles that it licensed to a Puerto Rican affiliate.
Kevin Pinner, Top International Tax Policy to Watch in 2026, Law360.com (Jan. 2, 2026):
The details of a proposed U.S. exemption from the global minimum tax’s international provisions, possible retaliatory measures by the U.S. government and the rollout of major changes in Congress’ latest budget are high priority for tax professionals going into 2026.
Maria Koklanaris, State and Local Tax Cases to Watch in 2026, Law360.com (Jan. 2, 2026):
From Florida’s suit against California over single-sales-factor apportionment to matters in New York and New Jersey challenging an interpretation of when a federal law applies to internet transactions, 2026 promises to reveal a lot about state and local tax law.
Paul Williams, State and Local Tax Policy to Watch in 2026, Law360.com (Jan. 2, 2026):
State decisions on conforming to tax changes in this year’s federal budget reconciliation bill and debates over whether taxes will be necessary to address looming budget challenges appear primed to headline state and local tax policy discussions in 2026.
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