Lin Zhe, a professor at the Central Party School: "Black income" is illegal income; "White income" is open and transparent income, which is legal; "Gray income" is income between the two. The connotation of "grey income" is very complicated. In the 1980s, people called economic income other than wages and allowances, such as royalties, part-time income, patent transfer fees, etc., all called "grey income."
Origin: The term "grey income" first came from the judicial organs. On December 10, 1998, the Heilongjiang Provincial Higher People's Court used the term "grey income" for the first time in the trial of Zhu Shengwen's case. (Given that in various economic cases, it is usually impossible to completely trace the source of illegal income of criminal suspects, the editor prefers to judge the "gray income" in this case as "black income".)