Three organizations that represent biofuel producers have asked to intervene in the latest legal challenge to Renewable Fuel Standard (RFS).

The Renewable Fuels Association (RFA), Growth Energy, and the Biotechnology Industry Organization (BIO), filed a motion Friday with the U.S. Court of Appeals for the District of Columbia Circuit to intervene in the challenge against the RFS by Monroe Energy, the American Petroleum Institute (API) and the American Fuel and Petrochemical Manufacturers (AFPM). The lawsuit seeks a reduction of the 2013 volume obligations for all renewable fuels.

The groups are asking the Court’s permission to intervene in this lawsuit on behalf of member companies which would be directly impacted by that action. “Moreover, a reduction in the volumetric requirement for any one type of renewable fuel under the RFS could affect the demand for other types of renewable fuels,” the groups stated in the filing.

In January, the same court upheld EPA’s authority to set advanced and cellulosic biofuel volume obligations at the maximum achievable level, in order to achieve Congress’ intent to promote production and use of renewable fuels. The trade groups will ask the Court to reaffirm this finding.