NASCAR has released the post-race penalty report following the race weekend at Road America.
There was one penalty for a safety infraction:
Sections 10.9.10.4: Tires and Wheels
Note: Lug nut(s) not properly installed.
#14-Chase Briscoe Crew chief John Klausmeier has been fined $20,000 and suspended from the next NASCAR Cup Series Championship Points Event.
Chase Briscoe's crew chief, John Klausmeier, has been suspended one race by NASCAR for a lug nut violation at Road America. Michael Cook is listed as Briscoe's crew chief for Sunday's race at Atlanta.
— Jordan Bianchi (@Jordan_Bianchi) July 6, 2021