The movie 3 idiots, novel five point someone and the adaptation rights

Описание: The adaptation rights acquired through licence from an author by a producer or director means the concept can be adapted to a cinema, the plot can be changed accordingly by the script writer. The author of the novel will not have rights in the screenplay , hence the screenplay credits will not be given to the writer’s credit. This is what happened in the movie 3 idiots and Chetan Bhagatwas given due credit only for the adaptation right given by him