Accountancy firm PwC will continue to work for the Oscars, in spite of an envelope mix-up at the awards ceremony that saw "La La Land" temporarily given the Best Picture statuette rather than "Moonlight."
In a letter to members shown to Reuters, Cheryl Boone Isaacs, president of the Academy of Motion Picture Arts and Sciences, said that PwC had made a "presentation of revised protocols and ambitious controls," following the embarrassing botch.
She added that the Academy had been "unsparing in our assessment that the mistake made by representatives of the firm was unacceptable."
Mobile phones and other devices will have to be handed over before accountants go backstage, Boone Isaacs said.
Actors Faye Dunaway and Warren Beatty were handed the wrong category envelope at the ceremony last month, with the card inside saying: "Emma Stone, La La Land." A confused Dunaway then announced that "La La Land" had won Best Picture, and after three speeches by the film's production team, producer Jordan Horowitz explained the mistake and held up the correct card, showing that "Moonlight" had in fact won.
PwC, which has overseen the Oscars ballot for 83 years, has previously apologised for the mix-up.
US board chairman Brian Cullinan and tax partner Martha Ruiz have led ballot-counting for the Oscars for the past few years, and PwC chair Bob Moritz told CNBC he knew it had "a challenge" as he watched the ceremony at home.
Cullinan, who handed out the Best Picture envelope, had tweeted a picture of Stone just three minutes before Beatty and Dunaway walked on stage and announced the wrong Best Picture winner.
The Academy and PwC, also known as PricewaterhouseCoopers, did not respond to a CNBC request for comment.