The district court erred in certifying a plaintiff class in this case challenging defendant’s classification of its property preservation workers as independent contractors and asserting claims for overtime pay and expense reimbursement. Plaintiffs could not prove fact of damage–not just amount of damage–by common evidence since some class members had not worked overtime or incurred reimbursable business expenses. The district court also erred in granting summary judgment because triable issues remained as to whether the workers were independent contractors under the Borello test as to the expense reimbursement claim, or under new Lab. Code 2785(b) under which the ABC test adopted in Dynamex does not apply to a bona fide business-to-business contracting relationship. Some class members had formed sole proprietorships or were employed by their own or another’s corporation. The ABC test might not govern these class members’ claim for overtime wages. The decision also reverses an interim award of attorney fees to plaintiffs’ attorneys since it was based on the reversed class certification and summary judgment orders.