The basic reasons are that the belongingness of commercial exploitation right of sports stars isn't clear and definite and management mechanism is imperfect.

认为，其根本原因是体育明星运动员的商业开发权归属不清，管理机制不完善。

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According to this right, a person (mainly a celebrity) can control and profit from the commercial exploitation of his or her identities.

根据这项权利，一个人(主要是知名人物)可以控制对其形象的商业开发并从中获益。

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Publicity laws grant famous personalities the right to control the commercial exploitation of certain aspects of their identity, such as their names and likenesses.

FORBES: Encores By Marilyn Monroe, Tupac and Elvis Raise Publicity Rights Concerns