Legal Question in Civil Litigation in California

If it was in the course of business, of course the business would be liable along with the owner who committed the tort. In fact, if the owner was acting in the capacity as an employee, the business could be obligated to indemnify him except in cases of egregious intentional torts.

Maybe. It would depend upon the facts. That the tortfeasor owns part of the business and was on the premises at the time would not be enough to make the business liable. But if she acted while carrying out company business, the company might very well be liable. Note that the same would be true if she was off-site at the time and/or if she was just an employee rather than an owner.

Note also that the company is more likely to be liable for a negligent tort committed during the course of business than for an intentional tort. As I said earlier, it would depend upon the facts.