Paris: Red Bull on Tuesday lost their appeal over Daniel Ricciardo's disqualification from second place in last month's Australian Grand Prix.
The world champions had sought to overturn the stripping of Ricciardo's runner-up finish behind Nico Rosberg in Melbourne for breaching fuel flow regulations.
FIA's International Court of Appeal issued a ruling after a six-hour hearing Monday during which Mercedes had called for the punishment to be harsher.
Red Bull said they "accepted the decision" but were "disappointed" with the outcome which left their rookie Australian driver 10th in the championship with 12 points, 49 behind Mercedes' pacesetter Rosberg ahead of Sunday's Chinese Grand Prix.
Red Bull are fourth in the constructors' standings on 35 points with Mercedes leading on 111.
The ruling is a blow to Red Bull's hopes of retaining their world titles as a reinstatement would have been worth 18 points which would have lifted Ricciardo into third in the driver's race and his team into second in the constructors' standings.
"Those points are vital. Every point is vital," Red Bull team principal Christian Horner had said before the hearing.
Red Bull were found guilty of not only using more than the 100kg fuel limit per hour in Melbourne but also of ignoring FIA advice during the race to limit their fuel consumption.
Ricciardo, 24, has had a roller-coaster start to his debut season. In Malaysia he drove off with a loose wheel after a pit stop, and in Bahrain he succeeded in taking fourth despite starting from 13th, outshining his teammate Sebastian Vettel.