SACRAMENTO, California —, 27 September 2026 - California has eased permitting and reporting requirements for certain mixtures containing gamma-butyrolactone (GBL; CAS 96-48-0), removing state-specific obligations affecting the solvent’s use in semiconductor manufacturing and research.
Governor Gavin Newsom signed Senate Bill 1306 (SB 1306) on 27 September 2026. The law exempts qualifying mixtures containing 70% or less GBL by weight or volume from several California controls that do not apply to comparable mixtures under federal rules.
California removes state-specific GBL requirements
GBL is used as a solvent in semiconductor manufacturing and research. Because California regulates it as a precursor chemical, companies handling GBL have been subject to requirements administered by the California Department of Justice (DOJ).
For qualifying mixtures, SB 1306 removes California DOJ permitting requirements to sell, transfer, furnish, or obtain GBL; transaction reporting; reporting when GBL is obtained from outside California; and specified theft or loss reporting.
The law also removes certain bill-of-sale requirements for chemical reagent or solvent transactions valued above $100 when those requirements are triggered solely by the presence of GBL.
The exemption covers qualifying mixtures that are obtained or received, sold, transferred, exported, or otherwise furnished, extending the change beyond semiconductor manufacturers to suppliers and distributors handling those mixtures.
Definition of GBL mixtures
The exemption applies to mixtures containing 70% or less GBL by weight or volume and at least one other substance that is not solely an inert carrier or impurity. An inert carrier is a chemical that does not interfere with GBL's function but helps deliver it for use in a chemical process.
Pure GBL and mixtures that do not meet these conditions remain subject to California's existing controls.
Closes the gap with US federal rules
The US Drug Enforcement Administration (DEA) has exempted qualifying mixtures containing 70% or less GBL from comparable federal controls since 2010, while California continued to regulate GBL at any concentration.
California lawmakers said the difference imposed additional permitting and reporting requirements on semiconductor fabrication facilities that rely on specialized industrial chemicals and solvents.
TechNet, which supported SB 1306, called the legislation a “technical fix” aligning California with existing DEA standards while maintaining public-safety protections.
“SB 1306 brings California in line with federal standards, cuts unnecessary red tape,” Senator Dave Cortese said after the bill was signed.
SEMI Americas President Joe Stockunas said the measure provides greater “clarity and alignment” for the semiconductor ecosystem while maintaining safety and responsible industry practices.
Although semiconductor manufacturing champions the legislation, the exemption is based on the composition of the GBL mixture, and thus other industries using GBL mixtures would also be exempted. Other industrial uses of GBL include solvents in paint strippers, superglue removers, and circuit board cleaners.
Companies handling GBL mixtures in California should confirm the GBL concentration and other components in each mixture before treating it as exempt. Pure GBL and mixtures outside the exemption remain subject to the existing state requirements.