Carlos Sainz and Lewis Hamilton were among eight drivers demoted after race stewards ruled late on Sunday that they had committed track limits violations in the Austrian Grand Prix.
In a race of attrition, punctuated by safety cars, the stewards found they had lost track of some of the violations.
A note from the sport's governing body FIA said there had been more than 1,200 potential track limits breaches in the race.
In the confusion, Aston Martin filed a post-race protest.
Late on Sunday evening, after checking their sums, the stewards penalised eight drivers.
"An examination of the list of deleted lap times... revealed that a number of track limit infringements had not previously been referred to the Stewards for potential penalty," said a statement.
"It was determined that some of these infringements warranted a penalty that was not previously applied."
BREAKING: Eight drivers receive post-race penalties for track limit infringements during the race
The top 10 results change, although the podium remains unaffected #AustrianGP #F1 pic.twitter.com/scwtaQG96q
Five racers in points positions were all found to have committed one breach and had 10 seconds added to their times.
Sainz of Ferrari, the highest-placed finisher to be punished, dropped from fourth to sixth. Lando Norris of McLaren Mercedes and Fernando Alonso of Aston Martin both gained a position.
The Austrian Grand Prix race start in all its glory 🍿#AustrianGP #F1 pic.twitter.com/g7ehAd8BKj
Hamilton fell from seventh to eighth, swapping places with Mercedes teammate George Russell.
Pierre Gasly of Alpine dropped a place to 10th. Alex Albon of Williams Mercedes was punished but stayed in 11th just outside the points.
Esteban Ocon, who accumulated four penalties for a total of 40sec added to his time, fell two spots to 14th. Nyck De Vries had two penalties for 15sec and Yuki Tsunoda one for 5sec, which dropped him to last among the 19 finishers.
AFP