On June 10, 2019, the U.S. Supreme Court overturned a Ninth Circuit wage-and-hour ruling that had exposed oil and gas companies to hundreds of millions of dollars in back-pay liability. The decision was a victory for WLF, which filed a brief urging reversal of the lower-court opinion. At issue was whether federal law or California law should govern wage payments to employees working on platforms located on the Outer Continental Shelf off the coast of California. Rejecting a half-century of prior case law, the Ninth Circuit chose California law, under which employees who do not leave their job site at night must be paid for all 24 hours in a day, including time spent sleeping. The Supreme Court unanimously reversed. It agreed with WLF that a 1953 federal statute dictates application of federal law to activities on the Outer Continental Shelf, and provides for incorporation of the law of the adjacent State only if doing so is necessary to fill a gap in federal law.