My company has informed me that I cannot do a progress billing on a lump sum contract for a non-government agency due to federal tax law. I am trying to find the actual law that pertains to this so I can research it but I'm not sure where to find it or even what it might be called. The project is in Nevada, but the corporate office for my company is in California; I am located in Nevada. Can you please help me get to the appropriate government resource?