Superdollar

A superdollar (also known as a superbill or supernote) is a very high quality counterfeit United States one hundred-dollar bill, alleged by the U.S. government to have been made by unknown organizations or governments. In 2011, government sources stated that these counterfeit bills were in "worldwide circulation" from the late 1980s until at least July 2000 in an extradition court case.

While there are many features on supernotes that can be detected with conventional methods, new, more sophisticated supernotes could be produced to circumvent some conventional detection methods. Thus it may be possible to see some supernotes in circulation until they are detected.

Various groups have been suspected of creating such notes, and international opinion on the origin of the notes varies. The U.S. government believes that North Korean officials have passed off supernotes in various countries and accuses North Korea of producing them. Over $35 million worth of counterfeit $100 bills were produced by British criminals, who were arrested in 2002.

A new $100 bill design intended to thwart counterfeiting, incorporating a "3D security ribbon", color-shifting numerals and drawings, and microprinting, entered circulation in 2013.