8 CFR Sec. 214.2(i) Representatives of information media
The admission of an alien of the class defined in section 101(a)(15)(I) of the Act constitutes an agreement by the alien not to change the information medium or his or her employer until he or she obtains permission to do so from the district director having jurisdiction over his or her residence. An alien classified as an information media nonimmigrant (I) may be authorized admission for the duration of employment.
This information can be found in the Code of Federal Regulations.