The Supreme Court has stopped the Biden administration from enforcing a requirement that employees at large businesses be vaccinated against COVID-19 or undergo weekly testing and wear a mask on the job.

At the same time, the court is allowing the administration to proceed with a vaccine mandate for most health care workers in the U.S.

The court’s conservative majority concluded the administration overstepped its authority by seeking to impose the vaccine-or-test rule on U.S. businesses with at least 100 employees. More than 80 million people would have been affected by the mandate.