15 days. The validity period of approval for activities of art business units is 15 working days. A work of art is the result of an artist's intellectual labor. As a special commodity, it circulates in the art market. Like other commodities, it also has the basic attributes of ordinary commodities: use value and value; The difference is that the use value of artistic works is embodied in the spiritual level rather than the material level, and it is aimed at meeting some aesthetic and spiritual needs of people.