The Biden administration’s vaccination mandate for larger employers is not a done deal.

On Saturday, Nov. 7, a federal appeals court temporarily blocked the new regulations, which require all employees at companies with 100 workers or more to be vaccinated against COVID-19 or to submit to weekly coronavirus testing.

The Louisiana-based Fifth U.S. Circuit Court of Appeals issued the emergency stay as the three-judge panel felt the mandate raises “grave statutory and constitutional issues.” The court ordered the Biden administration to file legal papers by the afternoon of Monday, Nov. 8, as it considers whether to issue an injunction against the vaccination and testing regulations.

The ruling came in response to a petition filed by a group of businesses, religious groups, advocacy organizations and several states, including Louisiana and Texas. The petition argued that the Biden administration is exceeding its legal authority by trying to require vaccination and mandatory testing.

On Thursday, Nov. 4, the U.S. Labor Department’s Occupational Safety and Health Administration (OSHA) formally announced the regulations and issued guidance for how companies should proceed to meet them. That included setting a deadline of Jan. 4. 2022, for companies to ensure workers are vaccinated or being tested weekly for COVID. By Dec. 5, unvaccinated employees must begin wearing masks at indoor workplaces, according to the Biden administration’s rules.

Still, the regulations are facing a strong legal backlash. For instance, the Associated Press reported that at least 27 states have filed lawsuits challenging the rule. “This mandate is unconstitutional, unlawful and unwise,” said the court filing by Missouri Attorney General Eric Schmitt.

Jan. 4. That's the deadline by which companies with 100 or more employees must have workers fully vaccinated against #COVID19. Unvaccinated employees will have to submit to weekly testing. https://t.co/7zafDkgoDh @ASI_MBell @asicentral @TheresaHegel

— Chris Ruvo (@ChrisR_ASI) November 4, 2021

“Biden’s new vaccine mandate on private businesses is a breathtaking abuse of power,” Ken Paxton, Texas attorney general, tweeted last week. “This latest move goes way outside those bounds. This ‘standard’ is flatly unconstitutional. I’m asking the court to strike it down.”

Officials within the Biden administration asserted what they call a “standard” is on solid legal ground and will withstand any court challenge, once fully adjudicated.

“The Occupational Safety and Health Act explicitly gives OSHA the authority to act quickly in an emergency where the agency finds that workers are subjected to a grave danger and a new standard is necessary to protect them,” Seema Nanda, top legal adviser to the U.S. Labor Department, said in a statement reported by The Wall Street Journal.

White House Chief of Staff Ron Klain added: “It’s common sense. If OSHA can tell people to wear a hard hat on the job, to be careful with chemicals, it can put in place these simple measures to keep our workers safe.”

President Joe Biden says he has issued the rules in the interest of public health. The president’s administration estimates that the requirement will save thousands of lives and prevent more than 250,000 hospitalizations over the six months following its implementation.

OSHA is planning on-site inspections of workplaces to ensure that companies are conforming to the mandate. Penalties for violations can range from $13,653 for a serious offense to $136,532 for a company that willfully flouts the rules.

Under the OSHA regulations, employers must provide employees with paid time off to get vaccinated and to recover from the side effects of the shots. Employers are not required to pay for testing of unvaccinated employees.