45 C.F.R. § 171.301
An actor's practice of limiting the content of its response to or the manner in which it fulfills a request to access, exchange, or use electronic health information will not be considered information blocking when the practice meets all of the following conditions.
(a) Content condition—electronic health information. An actor must respond to a request to access, exchange, or use electronic health information with—
(b) Manner condition—(1) Manner requested.
(ii) If an actor fulfills a request described in paragraph (a) of this section in any manner requested:
(2) Alternative manner. If an actor does not fulfill a request described in paragraph (a) of this section in any manner requested because it is technically unable to fulfill the request or cannot reach agreeable terms with the requestor to fulfill the request, the actor must fulfill the request in an alternative manner, as follows:
(i) The actor must fulfill the request without unnecessary delay in the following order of priority, starting with paragraph (b)(2)(i)(A) of this section and only proceeding to the next consecutive paragraph if the actor is technically unable to fulfill the request in the manner identified in a paragraph.
(B) Using content and transport standards specified by the requestor and published by:
(1) The Federal Government; or
(2) A standards developing organization accredited by the American National Standards Institute.
[85 FR 25955, May 1, 2020, as amended at 85 FR 70085, Nov. 4, 2020]