A Kaiser Family Foundation poll in May found that nearly a third of unvaccinated Americans said they would be more likely to get the shot once it was fully approved. That response dwarfs the portion of unvaccinated people who said they would be swayed by time off work or free incentives.

Other people may get the vaccine because they are required to do so. The U.S. Army has indicated that it will make coronavirus vaccines mandatory starting in September, if they have full FDA approval. And full approval would also make it easier for employers and schools to mandate vaccines.

The lack of full authorization has been a core part of the messaging and litigation strategy of anti-vaccine groups. And while a federal judge upheld at least one large Texas hospital’s mandate for its employees, many employers are cautious about inviting litigation.

Dorit Rubinstein Reiss, a professor at the University of California Hastings College of the Law, argues that employers should be able to legally mandate vaccines that are under emergency use authorization, but she admits they’ll have an easier time of it with full approval.