The U.S. District Court of Northern Texas ruled in favor of United Airlines (UAL  ), allowing the airline to enforce its vaccine mandate.

District Court Judge Mark T. Pittman found that United Airlines' mandate was legal, dismissing claims that workers had been put in an "impossible position" by the mandate. Judge Pittman remarked that human resource decisions, specifically United's handling of employees applying for exemption, were the company's business. The crux of the Judge's argument is that exemption options were provided, meaning that employees hadn't been forced actually to accept the vaccine.

"We are working to identify non-customer facing roles where accommodated employees can apply and continue working until it is safe for them to their return to their current positions," United said in response to the decision. The company added that the approximately 2,000 workers who have applied for exemptions but do not accept a non-customer facing position would be put on leave.

United Airlines has been the most proactive in pushing for coronavirus vaccinations among airlines. As a federal contractor, the airline was included under President Joe Biden's initial vaccine mandate. In late September, the company announced that over 99% of its non-exempt workforce had been vaccinated. At the time, just under 600 employees had remained un-exempt and un-vaccinated, though that number quickly dropped over subsequent weeks. While the company stated that any remaining workers would be fired, it is unknown if United has followed through with this.

"I know that some don't support vaccine requirements, including some of our people and some of you receiving this note. But at United, we did it because we knew it was the right thing to do from a safety perspective, and as an airline, that's our highest priority. This vaccine requirement issue is now in the rear-view mirror for us and allows us to focus on taking care of our customers," CEO Jack Kirby wrote last week, addressing resistance from within the company.

Shares of United don't appear to have reacted all too much to the news. UAL share prices slid 1.4% during trading on Monday. That slide seems to have gotten a bit worse as trading began on Tuesday, with shares down an additional 1.9% by noon.