On Tuesday, the U.S. Supreme Court ruled that Integrity Staffing Solutions, Inc. is not required to pay warehouse workers for time spent undergoing daily anti-theft security screenings before leaving the Amazon warehouse where they worked. Justice Clarence Thomas, delivering the unanimous opinion, concluded that the time spent waiting to undergo (and undergoing) security screenings at shift’s end was not “integral and indispensable” to the warehouse workers’ principal duties to retrieve products from the warehouse shelves and package them for shipment. Integrity Staffing’s security screening required warehouse workers to remove such items as wallets, keys, and belts and pass through metal detectors. Employees also had to wait in line to pass through the screenings—allegedly up to 25 minutes each day. The employees argued that they should have been compensated for this time because the company required the security screenings and benefitted from them through reduced employee theft. The Supreme Court disagreed, noting that Congress enacted the Portal to Portal Act in the 1940s to stem a tide of FLSA litigation over pre-shift activities and to exclude from compensable work those activities that are “preliminary to or postliminary to” employees’ “principal activities.” Courts have defined “principal activities” as those which are an “integral and indispensable part of the principal activities.” The Supreme Court offered several reasons for classifying Integrity Staffing’s security screenings as non-compensable postliminary activities. First, the security screenings were not these employees’ principal duties; Integrity Staffing did not employ its warehouse workers to undergo security screenings, but rather to retrieve and pack products for shipping. Second, the security screenings were not “integral and indispensable” to these duties. Justice Thomas noted that “Integrity Staffing could have eliminated the screenings altogether without impairing employees’ ability to complete their work.” In her concurring opinion, Justice Sonya Sotomayor agreed, and added that “an activity is ‘indispensable’ to another principal activity only when an employee could not dispense with it without impairing his ability to perform the principal activity safely and effectively.” The lower court that ruled against Integrity Staffing erred—the Supreme Court ruled—by focusing on whether Integrity Staffing required the security screenings. Instead, the focus should be on the work that the employee is employed to perform. Interestingly, the U.S. Solicitor General, speaking on behalf of the U.S. Department of Labor, backed Integrity Staffing, noting that the Department of Labor’s regulations and opinion letters support Integrity Staffing’s approach. Today, employers face a tide of FLSA litigation twice the size of that faced by employers during the 1940s. So the Supreme Court’s ruling is welcome news.