Sponsored by Representative Henry Waxman, Chairman of the House Energy and Commerce Committee, and Representative Edward Markey, Chairman of the House Select Committee on Energy Independence and Global Warming, the bill was passed in the evening of on Friday June 26.

It requires a 17% reduction in carbon emissions from major US sources by 2020, compared to 2005 levels and an 83% reduction by 2050. This would be achieved through a cap-and-trade system that would impose a limit on carbon emissions