Updated April 9, 2021 2:20 pm ET

Amazon.com Inc. employees in Alabama voted not to unionize, handing the tech giant a victory in its biggest battle yet against labor-organizing efforts that fueled national debate over working conditions at one of the nation’s largest employers.

An estimated 71% of the Bessemer, Ala., warehouse workers who cast ballots voted against joining the Retail, Wholesale and Department Store Union, according to the National Labor Relations Board, which on Friday finished counting all the votes that weren’t challenged. The federal agency has yet to certify the results but noted that the challenged ballots aren’t enough to exceed the vote margin against unionization.

Shares of Amazon rose more than 1% to the highest level in two months.

The Bessemer facility employs less than 1% of the roughly 950,000 Amazon employees in the U.S., but the vote emerged as a watershed moment for a company that hired faster than almost any private corporation in history last year.

“Amazon didn’t win—our employees made the choice to vote against joining a union,” the company said in a statement. Amazon said it has “worked hard to listen to them, take their feedback, make continuous improvements” and would keep working “to get better every day.”