He had said that less invasive measures could protect public health, like masking, social distancing and remote work.
In 2019, President Donald J. Trump appointed Judge Brown to the U.S. District Court for the Southern District of Texas.
In its ruling on Thursday, the appeals court said that the lawsuit challenging the mandate, which was filed by the group Feds for Medical Freedom, should be dismissed.
Mr. Biden’s mandate, which also applies to health care workers and certain private sector employees, was prompted in part by the Delta surge.
As of Thursday, two-thirds of eligible Americans were fully vaccinated, according to a New York Times database.