(5) Related party defined For purposes of this section, the term “related party” means, with respect to a case under this subchapter involving a specific individual entitled to benefits under part A or enrolled under part B, or both, any of the following: (A) The Secretary, the medicare administrative contractor involved, or any fiduciary, officer, director, or employee of the Department of Health and Human Services, or of such contractor. (B) The individual (or authorized representative). (C) The health care professional that provides the items or services involved in the case. (D) The institution at which the items or services (or treatment) involved in the case are provided. (E) The manufacturer of any drug or other item that is included in the items or services involved in the case. (F) Any other party determined under any regulations to have a substantial interest in the case involved.