IMSA has clarified the criteria for manufacturers competing in the GT Daytona class next year, amid the arrival of new machinery and increased manufacturer support for the 2016 WeatherTech SportsCar Championship season.

Up to a dozen manufacturers could be represented in GTD next year, which according to IMSA President and COO Scott Atherton, would see certain financial and/or marketing commitments from each party in order to be represented on the grid.

“We will retain that criteria which has been the case; that’s not new,” Atherton told Sportscar365.

“There’s always some speculation and there’s a lot of misinformation out there on what IMSA’s demands are.

“I don’t think it’s appropriate for us to detail those because there’s no two agreements that are alike. They’re [all] very similar.

“It’s not like somebody has a free ride, so to speak, but there’s a commitment that must be made by any manufacturer participating with us in order to compete here.”

While GTD transitions to full-spec GT3 machinery next year, not every FIA GT3-homologated car will be eligible to compete in the WeatherTech Championship, with only manufacturers that have made commitments to IMSA set to be on the approved car list.

Manufacturers such as Audi, BMW, Porsche, Lamborghini, Ferrari and Nissan are already locked in by being Automotive Partners of IMSA, with other such as Mercedes and Lexus expected to soon follow.

However, there have been some manufacturers on the fence, notably Aston Martin and Dodge, which up to now have not been an Automotive Partner, and therefore not eligible for the GTD Manufacturers’ Championship.

Atherton confirmed both manufacturers, which run generic IMSA windshield banners instead of manufacturer badges, have smaller commitments than others, but would not elaborate any further.

“We have honored commitments that were made that preceded the merger,” he said.

“[2016], I believe, gives us an opportunity for us to have a ‘clean break’ so much that everyone is held to a similar criteria.”

It’s understood IMSA was in discussions with prospective GTD manufacturers last weekend at Road Atlanta, including McLaren, which currently does not have a commitment with the sanctioning body.

Existing manufacturers such as Riley Technologies, constructor of the Dodge Viper GT3-R, have also been working with IMSA to come to an agreement for its car to continue competing next year.

The fate of Aston Martin’s involvement in GTD, however, is unclear.

IMSA will allow all FIA GT3-homologated cars to take part in next month’s open test at Daytona, a test which is expected to see numerous new machinery such as the Lamborghini Huracán GT3 and Mercedes-AMG GT3 make their North American public debuts.