Third Party Injuries Are Not Derivative of Workplace Injuries Just Because They Are Caused by an Employee’s Injury In See’s Candies, Inc. v. Superior Court, B312241 (Cal. Ct. App. December 21, 2021), the defendants petitioned for a writ of mandate directing the trial court to vacate an order overruling their demurrer to a wrongful death action filed by the plaintiffs. The plaintiffs were the wife and daughter of the deceased, Mr. Ek. The plaintiffs alleged that Mr. Ek died from COVID-19 after catching the disease from his wife, who contracted the disease while at work for the defendants because the defendants failed to implement adequate safety measures. The defendants filed a demurrer and argued that the plaintiff’s claims were barred by the “derivative injury doctrine” of the Workers’ Compensation Act (“WCA”) because the plaintiff’s claim would not exist absent an injury to the employee. Third-party injuries are not subject to the derivative injury doctrine merely because they are caused by an employee injury Under the “derivative injury doctrine,” the workers’ compensation system is the exclusive remedy for certain third-party claims deemed collateral to or derivative of the employee’s injury. Claims for derivative injuries are those for the economic and intangible losses suffered by an employee’s loved ones as a result of the employee’s disability or death. A claim for separate physical injuries suffered by non-employees, even when an employee’s injury was part of the causal chain leading to those injuries, is not derivative. The plaintiffs’ claim is not for a derivative injury The California Court of Appeal for the Second District explained that even if the wife’s contraction of COVID-19 constituted an injury under the WCA, the plaintiffs did not seek damages for losses arising from that injury, such as loss of her support or companionship, or emotional trauma caused by observing her suffering. Nor did they sue for injuries that arose during the treatment of her injury or in the course of the workers’ compensation claims process. Instead, the plaintiffs sued for damages arising from the death of Mr. Ek, an event allegedly causally related to the wife’s infection by the virus at the workplace, but not derivative of that injury under the law. Disposition The Court denied the defendant’s petition for a writ of mandate directing the trial court to vacate an order overruling their demurrer to the plaintiffs’ wrongful death action.