In the past few days, stories broke that the rapper Shawn Carter (a/k/a "Jay-Z") is cavorting with University of South Carolina defensive end, Jadeveon Clowney. Clowney is projected to be the number one pick in next year's NFL Draft, and is famous for this hit. Although the University said Clowney did not violate NCAA rules by speaking with Carter, the rapper should be careful about his dealings with college athletes. Carter just recently became a sports agent, and his visibility may work against him if continues to meet with college athletes while they are still eligible with their schools.
In a number of states, it is a crime to give student-athletes a reward for their performance. For instance, Iowa's law addressing the matter was enacted in 1988. Presumably, this was in response to the 1986 Iowa State recruiting scandal. Iowa is not unique. The state prohibitions are not easily enforced because of the veil of secrecy under which impermissible benefits are given, but Carter's visibility destroys that secrecy.
College athletes are undoubtedly attracted to Carter, and they risk becoming ineligible if they contract with Carter for future representation before their eligibility expires. But Carter risks criminal offenses if he runs afoul of the wrong school, and gives or promises anything to an athlete as a reward while eligible. Oral contracts are valid, so even if Carter and a prospective student-athlete do not put anything in writing, an agreement for future representation could be a crime.