Cal. Bus. & Prof. Code § 14481

Any person engaged in the business of supplying clean laundered garments, towels, table linen or other articles, the property of the supplier, in a regular service, periodically exchanging clean articles for soiled for a fixed compensation, may adopt and use a name or other mark or device woven, impressed or produced thereon as an indicium of ownership, and may register the name, mark or device by filing and publishing it under this article.