Health and Safety Code § 8629

When there are several owners of a plot, or of rights of interment in it, they may designate one or more persons to represent the plot and file written notice of designation with the cemetery authority. In the absence of such notice or of written objection to its so doing, the cemetery authority is not liable to any owner for interring or permitting an interment in the plot upon the request or direction of any coowner of the plot.