K-pop has spawned an entire industry such as production houses and event management companies; music publishers; distributors of K-pop music and many K-pop and Hallyu other merchandise and service providers.The three biggest agencies in terms of revenue are S.M. Entertainment, YG Entertainment and JYP Entertainment,[166] often referred to as the "Big Three", whose stocks are traded at the Korea Exchange.[167] In K-pop these record labels also function as agencies for the artists.[166] They started operating as such at the beginning of the 2000s.[166] They are responsible for recruiting, financing, training, marketing and publishing new artists as well as managing their activities and public relations.