Mercedes' rivals are unhappy that the team conducted a three-day 1000 kilometre test in the week after the Spanish Grand Prix, using race drivers Lewis Hamilton and Nico Rosberg.
Although in-season test is banned in the Formula 1 regulations, it is understood Pirelli's contract with the teams allows it to call upon a team to help it test products when it is necessary to do so.
Pirelli motorsport director Paul Hembery reckoned there was nothing out of the ordinary about the test and that Mercedes will not have benefited because it did not know what products were being run.
When asked by AUTOSPORT if Mercedes could have gained an advantage in helping it understand its tyre problems, Hembery said: "Absolutely not, no. Because it's no relevance to what's happening here."
Hembery said the provision to use a team for a test was not unique to F1, and he suggested other teams had been called upon in the past.
"It's completely regular in that we are allowed to do 1000 kilometre of tyre testing with any team," he said.
"In the World Rally Championship contract it's exactly the same. We can do it with a representative car.
"We've done it before with another team and we've asked another team to do some work as well."
TEST FOCUSED ON 2014
Hembery insisted that most of the work at the test was on developments for 2014, with only a small element of it devoted to work on the tweaks being planned for the Canadian Grand Prix.
"In reality we were looking at next year's solutions and trying a variety of different [things]," he said. "Mercedes haven't got a clue what on earth we were testing in reality.
"It was 90 per cent for next year. We only changed [our plans for 2013 work] at the last minute."
Red Bull team principal Christian Horner was not convinced about Pirelli's views, however, and suggested Mercedes had gained from the test.
"Well, they got both cars on the front of the grid [in Monaco]," he said. "It has not hurt them."