Motorsport's governing body has reprimanded Mercedes and tire supplier Pirelli over a secret trial earlier this year. It has barred the German team from a young drivers' test in July.
The verdict was announced in Paris on Friday by the governing International Automobile Federation (FIA) after a hearing on Thursday.
The session was called after Mercedes appeared to have gone against the world governing body's ban on in-season testing by their current car and regular drivers Lewis Hamilton and Nico Rosberg. The 1,000-kilometre test was held between May 15 and 17.
Pirelli were summoned on the grounds they had allegedly failed to inform all the other teams of the test.
At Thursday's hearing, Mercedes produced a strong defence of their position concerning last month's tests in Barcelona, placing the blame on Pirelli.
It was alleged that Mercedes had breached FIA rules, which prevent competitors committing "any fraudulent conduct or any act prejudicial to the interests of any competition or to the interests of motorsport generally".
jr/ipj (Reuters, AFP)