Ferrari's Lewis Hamilton and Charles Leclerc were both disqualified from the Chinese Grand Prix on Sunday for technical infringements, along with Alpine's Pierre Gasly.
Leclerc and Gasly were found by FIA stewards to have cars that weighed less than the 800 kilogram minimum requirement while Hamilton was deemed to have excessive plank wear underneath his car.
Leclerc had finished fifth and Hamilton sixth. Their points will be expunged with all the drivers below them now moving up two places.
Gasly finished 11th so was already out of the points.
It was a disastrous end to a weekend that had started so brilliantly for Ferrari when Hamilton took his maiden win for his new team in Saturday's sprint.
The plank assembly is a skid plate which is designed to wear away when the floor strikes against bumps on the track or kerbs.
If it is too worn it can improve performance as cars can run closer to track, increasing "ground effect" down force.
"The plank assembly of Car 44 (Lewis Hamilton) was measured and found to be 8.6mm (LHS), 8.6mm (car centreline) and 8.5mm (RHS). This is below the minimum thickness of 9mm," said the stewards' ruling.
"The team also acknowledged that there were no mitigating circumstances and that it was a genuine error by the team."
For Leclerc the ruling said: "Car 16 (Charles Leclerc) was weighed by the FIA Technical Delegate inside and outside scales with both scales showing the same result of 799 kg after the customary draining of fuel and the replacement of a broken front wing."
"The calibration of both scales was confirmed and witnessed by the competitor. During the hearing there was no challenge to the FIA's measurements which are taken to be correct and that all required procedures were performed correctly.
"There are no mitigating circumstances and that the team confirmed that it was a genuine error by them."
Hamilton, driving a Mercedes, was disqualified from the 2023 United States Grand Prix for a similar plank-wear problem.
dh/mtp
