He then passed it to Dunaway who, seeing only La La Land named on the card, proclaimed it the winner.
“We sincerely apologise to Moonlight, La La Land, Warren Beatty, Faye Dunaway, and Oscar viewers for the error that was made during the award announcement for best picture,” a PwC statement said.
The company promised to investigate the error after Warren Beatty, who was presenting the best picture award with Faye Dunaway, ended up with the wrong envelope.
Stone said she had retained the envelope announcing her Oscar, so Beatty must have been holding the duplicate.