On April 16, 2010, TransCanada Power Marketing, Ltd, a power marketing company, filed a lawsuit in a Massachusetts federal court challenging the constitutionality of the solar "carve out" in Massachusetts' renewable portfolio standard (RPS) -- click here for a copy of the complaint. More specifically, the lawsuit alleges that the provision in Massachusetts law requiring electric suppliers to purchase a portion of their required renewable energy credits from in-state solar generators unlawfully discriminates against out-of-state solar developers. The ramifications of this lawsuit could be far-reaching on states such as Ohio with similar requirements in their RPS. In fact, Ohio's RPS contains a broader in-state requirement than Massachusetts that requires at least one-half of all renewable energy resources generated in Ohio to be derived from facilities located in Ohio.