But they are opposed to unilateral changes in contracts for existing fields.
The great bulk of commodity trading is in contracts for future delivery.
It trades in contracts for aluminium (its biggest business), copper, tin, nickel, lead, cobalt and steel.
Last year, more than 100 lawmakers earmarked $300 million in contracts for PMA's clients.
Campbell says the company has about $290m in contracts for the site.
Since its inception, the program has overseen more than $100 billion in contracts for oil exports and relief imports combined.
Random House has specified digital rights in contracts for the last decade, so recent works are not at issue.
An executive from Gulf Stream, which had $500m in contracts for 50,000 trailers, had assured FEMA that their tests showed formaldehyde levels below one government standard.
As of 2008, G.E. said that it had secured $700 million in contracts for 400 Olympic projects in and around Beijing for the 2008 Summer Games.
It has already secured $600m in contracts for the next 12 months, equal to around 30% of the global market for satellite imagery.
