45 CFR § 164.104
Applicability
April 14, 2021
(a) Except as otherwise provided, the standards, requirements, and implementation specifications adopted under this part apply to the following entities:
(1) A health plan.
(2) A health care clearinghouse.
(3) A health care provider who transmits any health information in electronic form in connection with a transaction covered by this subchapter.
(b) Where provided, the standards, requirements, and implementation specifications adopted under this part apply to a business associate.
[68 FR 8375, Feb. 20, 2003, as amended at 78 FR 5692, Jan. 25, 2013]