Cal. Bus. & Prof. Code § 14235

The classification of goods and services shall conform to the classifications adopted by the United States Patent and Trademark Office. A single application for registration of a mark may include any or all goods upon which, or services with which, the mark is actually being used indicating the appropriate class or classes of goods or services. When a single application includes goods or services that fall within multiple classes, the secretary may require payment of a fee for each class.