Tribunal Keeps AMT Offset Rule for Drugmakers
California's tax tribunal rejected a bid to overturn a 15-year-old precedent that governs corporate AMT offsets.
Updated on Nov. 2, 2026 in Biotech
California's Office of Tax Appeals ruled that a drugmaker, later acquired by Pfizer Inc., properly used research tax credits to offset its 2015 California alternative minimum tax liability. The tribunal's decision was made public on Monday, November 2, 2026, and is a state tax ruling rather than a technology development, so no shipped, announced, or research-stage status applies.
Why it matters
The ruling rejects the state Franchise Tax Board's request to overturn a 15-year-old precedent, In re NASSCO Holdings Inc., which had been set by the Board of Equalization, the tribunal's predecessor body. Keeping that precedent in place means companies facing California's corporate AMT can continue to rely on the offset rules NASSCO established.
The decision turns on the mechanics of California's corporate alternative minimum tax, which lets certain credits reduce a taxpayer's AMT liability. The tribunal found the drugmaker's use of research credits to offset its 2015 AMT matched the offset principles applied in NASSCO.
The players
Pfizer Inc.
A large biopharmaceutical company that acquired the drugmaker at the center of the ruling.
Franchise Tax Board
California's state tax agency, which asked the tribunal to overturn the NASSCO precedent and was rejected.
California Office of Tax Appeals
The state tribunal that issued the decision rejecting the Franchise Tax Board's request.
The details
The dispute centers on whether a taxpayer may apply research tax credits against its California alternative minimum tax liability, which is a separate minimum tax calculated alongside regular corporate income tax. In 2015 the drugmaker, later acquired by Pfizer Inc., did exactly that. The Franchise Tax Board challenged the practice, but the tribunal concluded the appeal's issue was almost identical to the one resolved in NASSCO, which allowed offsets using enterprise zone hiring credits and manufacturer's investment credits.
Timeline
2015 — the drugmaker applied research tax credits against its California AMT liability for that year.
November 2, 2026 — the Office of Tax Appeals decision was made public.
The Tech Race
The ruling reinforces a 15-year-old precedent, In re NASSCO Holdings Inc., that governs how California corporate taxpayers may offset their alternative minimum tax. Its extension to research tax credits matters for biopharmaceutical firms, which rely heavily on those credits.
Companies subject to California's corporate AMT, including biopharmaceutical firms that claim research credits, can rely on the offset principles affirmed in this ruling. The decision does not change current filing requirements, and the stub does not indicate any new compliance steps.
The takeaway
The ruling keeps the NASSCO offset framework intact for California taxpayers. Watch for any further appeal by the Franchise Tax Board, since a reversal would reopen how AMT credits are applied.
Further reading
For more on how drug development is financed and taxed, see the Biotech section.
