Whenever the Food and Drug Administration is notified that a record that it received from another agency was amended or is the subject of a statement of disagreement, the Food and Drug Administration shall:

(a) Discard the record, or clearly note the amendment or the fact of disagreement in its copy of the record, and

(b) Refer persons who subsequently request the record to the agency that provided it.

(c) If an accounting was made under § 21.71 (d) and (e) of the disclosure of the record under § 21.71(a), inform all previous recipients of the record about the amendment or provide to them the statement of disagreement and the agency statement, if any.