Carlos Sainz Jr. will get a 10-place grid penalty for the second Silverstone GP3 race, while Patrick Kujala has been suspended from the event for clashes with David Fumanelli.
Koiranen driver Kujala was launched over the top of Fumanelli's Trident car at Becketts in an incident that triggered a long safety period during Race 1. Kujala's car landed on top of the tire wall, but he escaped unhurt.
The stewards ruled that Kujala had hit Fumanelli twice in an "extremely serious breach of the regulations which had the potential to cause injury to others".
Sainz's punishment is for a late-race incident in which he forced Lewis Williamson off the road as the Bamboo driver drew alongside his MW Arden car on the run to Brooklands. The Red Bull protege moved across the width of the track with Williamson alongside him, sending his rival into the barriers and out of the race. Sainz subsequently fell to 13th, and will have to start 23rd on Sunday morning.
The other penalty issued was to Melville McKee, who had 20 seconds added to his race time for taking a jump-start penalty while the safety car was out.