221.42—When must a party supplement or amend information it has previously provided?

(c) Failure to disclose. (1) A party that fails to disclose information required under §§ 221.21(c), 221.22(c), or 221.24(c), or paragraphs (a) or (b) of this section, will not be permitted to introduce as evidence at the hearing testimony from a witness or other information that it failed to disclose.