Giovacchini v. The Cincinnati Insurance Company, 3:22-cv-07787

Plaintiffs Stefano Giovacchini et al. sued Cincinnati Insurance Company for denying coverage under their homeowners’ policy after a storm allegedly caused water damage to their home's interior and exterior.
Plaintiffs disclosed two experts: one to opine on cause, origin, and costs of damages (both interior and exterior), and another (a builder) as a non-retained expert.
Defendant disclosed two experts: one for cause and origin, and one (Jones) for scope and cost of repairs, but limited to interior damage and specifically excluded coverage and exterior repairs from his purview.
Plaintiffs then designated a rebuttal expert, Larsen (an attorney and adjuster), to address issues including insurance coverage and the scope/cost of repair—but failed to provide required disclosures and expert report under Rule 26(a)(2)(B).
Defendant moved to strike the rebuttal expert, arguing improper disclosure and that purported rebuttal testimony was not actually rebuttal under the Rules.
The procedural posture is a ruling on defendant's motion to strike and exclude the plaintiffs’ rebuttal expert and his opinions.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether plaintiffs' rebuttal expert opinions were proper rebuttal under Fed. R. Civ. P. 26(a)(2)	Rebuttal expert needed to counter limitations in defendant's expert's scope influenced by insurance policy	Testimony is not rebuttal since defendant’s expert didn’t opine on coverage; any other opinions duplicate prior experts	Not proper rebuttal; duplicative or outside scope
Whether failure to provide mandatory expert disclosures can be cured	Plaintiffs offer to cure deficiencies if that were the only problem	Disclosures were not proper; opposing sanctions for failure to comply	Plaintiffs may cure, but it does not affect the central issue
Whether rebuttal can address insurance coverage where it was not subject of opposing expert’s opinion	Needed to address limitations stemming from insurer's policy interpretation	Coverage is a legal question for the court, not expert testimony	No; coverage is legal issue, not proper for expert rebuttal
Whether offering opinions on coverage and exterior repairs is permitted as rebuttal where not addressed directly by original expert	Defendant’s expert’s limitations are based on policy determinations which misstate coverage	Limiting expert to interior repairs is consistent with their assignment; rebuttal can’t add new theories or case-in-chief opinions	Not permitted; should have been in plaintiffs’ initial case (not rebuttal)

Yeti by Molly, Ltd. v. Deckers Outdoor Corp., 259 F.3d 1101 (9th Cir. 2001) (failure to disclose expert under Rule 26(a) generally results in exclusion absent justification or harmlessness)
Devin v. United Servs. Auto. Ass'n, 6 Cal. App. 4th 1149 (Cal. Ct. App. 1992) (scope and interpretation of insurance policies are legal questions for the court, not for expert testimony)