California Code
ARTICLE 4 - Motion To Augment or Amend Expert Witness List or Declaration
Section 2034.630.

2034.630. The court shall impose a monetary sanction under Chapter 7 (commencing with Section 2023.010) against any party, person, or attorney who unsuccessfully makes or opposes a motion to augment or amend expert witness information, unless it finds that the one subject to the sanction acted with substantial justification or that other circumstances make the imposition of the sanction unjust.

(Added by Stats. 2004, Ch. 182, Sec. 23. Effective January 1, 2005. Operative July 1, 2005, by Sec. 64 of Ch. 182.)