The FIA reopened the case after a "new element" - believed to be radio traffic between the McLaren driver and his pitwall at the time of the incident - came to light.
A statement issued by the stewards on today confirmed that 24-year-old Hamilton and his team "acted in a manner prejudicial to the conduct of the event by providing evidence deliberately misleading to the stewards". The stewards also said the conduct was in breach of the International Sporting Code.
McLaren team principal Martin Whitmarsh said everyone was disappointed by what had happened but revealed that were no plans to appeal the decision. "I believe it was a harsh decision. Experience has told us you've got to accept these decisions," he said.
Toyota's Trulli, originally demoted to twelfth place having stood on the Albert Park podium, has had his third place result reinstated. Hamilton was originally awarded third place when stewards ruled that Trulli breached regulations by passing the McLaren driver during a safety car period late in the race.
Check out the full race results in our previous story by clicking here.