It's also an uncomfortable moment for Pirelli, who are currently bidding to maintain their exclusive contract for the provision of tyres to the world championship beyond the end of 2013.
However it's not entirely clear under what grounds the Tribunal is hearing any case against Pirelli, which is not a competitor and therefore not subject to adjudication under the sporting regulations in the same way that Mercedes is.
Pirelli's position in the sport is via commercial contract with the FIA and therefore any sanctions against the company - or even the termination of their services - would likely have to go through formal business legal proceedings rather than under the auspices of the International Tribunal, which at best could probably only make a non-binding recommendation to the FIA President Jean Todt over how he should proceed in the matter.
Red Bull team principal Christian Horner has since attempted to make it clear that his team's original complaint to the FIA was only against Mercedes and was never directed at Pirelli.
"I think the issue is nothing to do with Pirelli," he said. "They asked for a car to be used, and it is the entrants' responsibility to ensure that that car complies with the rules.
"Our issue is not to do with Pirelli, it is to do with the current entrant," he added, referring to Mercedes. "They broke the rules."