Out with the old and in with the new. This new energy efficiency standard prohibits production of traditional incandescent light bulbs in favor of more energy efficient varieties, like LED bulbs. Traditional bulbs that are still produced are being forced to use at least 27% less energy. The law was phased in during 2012 and was fully implemented in 2014. To read the law, visit the Government Printing Office or see the PDF attached below. Wikipedia is also a good source for an expanded summary.
*Source: www.energystar.gov