In Acosta v. SI Corp. (2005) 129 Cal.App.4th 1370, a group of homeowners jointly sued SI Corporation on a single theory--product liability for an allegedly faulty mesh used in the construction of their homes--and lost. (Id. at p. 1373.) SI Corporation submitted a single costs bill for all the plaintiffs, and the plaintiffs moved to tax costs on the ground that the company failed to apportion costs among each individual plaintiff. (Ibid.) The plaintiffs argued that their claims were separate, not joint, because 101 different homes were involved in the litigation, and each plaintiff had an interest in only the home that he or she owned. (Id. at p. 1374.) Citing the mandatory provision of Code of Civil Procedure section 1032, subdivision (b), which provides that "a prevailing party is entitled as a matter of right to recover costs," the appellate court held that a prevailing party defendant is not required to apportion costs among plaintiffs "where the plaintiffs were represented by the same law firm and pursued a single cause of action in a joint trial." (Acosta, supra, at p. 1376.) The court explained that "in most cases where a defendant is entitled to costs as of right because plaintiffs took nothing in their joint action, there will be nothing to apportion. The costs are joint and several because the plaintiffs joined together (represented by the same attorney) in a single theory of liability against a defendant who prevailed. It is up to the plaintiffs in a motion to tax costs to point out that some costs are not related to the joint theory of liability, but are specific to a particular plaintiff, and it is therefore not fair to include these in a joint award." (Ibid.) Because the plaintiffs failed to meet this obligation, the Acosta court held there was no error in awarding costs jointly and severally against the group of plaintiffs, who, after satisfying the cost award, would be entitled to seek contribution from each other.